Chemical and physical characteristics of alluvium from drill core near the Rabbit Creek gold deposit, Getchell mining district, Humboldt County, Nevada
Chemical and physical characteristics of alluvium from drill core near the Rabbit Creek gold deposit, Getchell mining district, Humboldt County, Nevada by…
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UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY Chemical and physical characteristics of alluvium from drill core near the Rabbit Creek Gold Deposit, Getchell Mining District, Hunboldt County, Nevada D.E. Detra*. D.J. Madden-McGuire*. S.M. Smith*, M.L. Silberman*, Theodore Botinelly*, D.J. Grimes*, W.H. Ficklin*, J.B. McHugh*, R.M. O'Leary*, and M.E. Hinkle* Open-File Report 89-455 This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature. Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS. *U.S. Geological Survey, DFC, Box 25046, MS 973, Denver, CO 80225
CONTENTS Page Introducti on Sample Preparation Explanation of Data Core Description Mi neralogy of Heavy-Mi neral Concentrates X-Ray Diffraction Analysis 31 Sequential Extractions of the -250 mesh Fraction for the Determination of 18 elements 36 Cold Vapor-Atomic Absorption Spectrophotometry (CV-AAS) for the Analysis of Mercury 43 Visible-Absorption Spectrophotometry for the Analysis of Tungsten 43 Ion Specific Electrode (ISE) Analysis for Fluoride 44 Flame Atomic-Absorption Spectroscopy (FAA) for the Determination of Sb, As, Bi, Cd, and Br 45 Arsenic Species Analysis 47 Gold Analysi s 49 Gas Chromotography for the Determination of COo, Op, S02 and CSp Total Atomic Emission Spectrographic Analysis for the Determination of 35 elements Atomic Emission Spectrography for the Determination of 35 Elements in Oxalic Acid Leachates 68 Atomic Emission Spectrography for the Determination of 35 Elements in Heavy-Mineral Concentrates from Drill Core 68 Explanation of Emission Spectrographic Data Tables 68 References 85 FIGURES Figure 1.--Rabbit Creek gold deposit location map TABLES Table 1. Weights of Rototap sieve shaker size fractions from the Rabbit Creek core samples Table 2. Heavy-mineral concentrate weights -100/+250 fraction Table 3. Heavy-mineral concentrate weights -20/+60 fraction Table 4. Descriptions of hand samples of alluvium from core at the Rabbit Creek gold deposit Table 5. Descriptions of thin sections Table 6. Weights of size fractions that were seived by hand from Rabbit Creek core samples 20 Table 7. Selected percentiles and statistical parameters of grain size, Rabbi t Creek core samples 21 Table 8. Mineralogy of the -100/+250 fraction, heavy-mineral concentrate Table 9. Mineralogy of the -20/+60 fraction, heavy-mineral concentrate... 27 Table 10. Peak heights from XRD patterns of -20/+60 mesh material from Rabbit Creek drill hole, Humboldt County, Nevada Table 11. Peak heights from XRD patterns of -60/+100 mesh material from Rabbit Creek drill hole, Humboldt County, Nevada 33
Table 12. Peak heights from XRD patterns of -100/+250 mesh material from Rabbit Creek drill hole, Humboldt County, Nevada 34 Table 13. Peak heights from XRD patterns of -250 mesh material from Rabbit Creek drill hole, Humboldt County, Nevada Table 14. Lower limits of determination for elements analyzed for by ICP-AES after extraction 37 Table 15. Determination of 18 elements after sequential extraction of -250 mesh fraction of Rabbit Creek drill core 38 Table 16. Analytical results for mercury shown in ppm 43 Table 17. Analytical results for tungsten shown in ppm 44 Table 18.--Analytical results for fluoride shown in ppm 45 Table 19. Analytical results for antimony, arsenic, bismuth, cadmium, and zinc shown in ppm 46 Table 20. Analytical results for extractable As species in sieved Rabbi t Creek core samples Table 21. Analytical results for extractable As species in selected clasts from Rabbit Creek core samples Table 22. Gold in alluvium from sieved core from Rabbit Creek drill hoie Table 23. Gold in selected clasts from core from Rabbit Creek drill hole Table 24. Gas chromotograph operating conditions Table 25. Analyisis of core samples for C02 , Oo, S02 and CSp Table 26.--Limits of determination for the spectrographic analysis of geologic materials, based on a 10-mg sample 55 Table 27.--Emission spectrographic results from the analysis of the -20/+60 sieve fraction of Rabbit Creek core Table 28. Emission spectrographic results from the analysis of the -100/+250 sieve fraction of Rabbit Creek core Table 29. Emission spectrographic results from the analysis of the -250 sieve fraction of Rabbit Creek core 60 Table 30.--Emission spectrographic results from the analysis of whole clasts from Rabbit Creek core 62 Table 31. Emission spectrographic results from the analysis of the -20/+60 ground sieve fraction oxalic acid leachate 69 Table 32. Emission spectrographic results from the analysis of the -20/+60 unground sieve fraction oxalic acid leachate Table 33. Emission spectrographic results from the analysis of the -100/+250 sieve fraction oxalic acid leachate Table 34. Emission spectrographic results from the analysis of the -250 sieve fraction oxalic acid leachate Table 35. Spectrographic results from the analysis of the -20/+60 fraction C-2 heavy-mineral concentrate from drill core Table 36. Spectrographic results from the analysis of the -20/+60 fraction C-3 heavy-mineral concentrate from drill core 79 Table 37. Spectrographic results from the analysis of the -100/+250 fraction C-2 heavy-mineral concentrate from drill core 81 Table 38. Spectrographic results from the analysis of the -100/+250 fraction C-3 heavy-mineral concentrate from drill core 83
INTRODUCTION A method is needed to identify mineral deposits buried by hundreds of feet of transported overburden. Drill core of the alluvium covering the Rabbit Creek gold deposits provides an opportunity to study the processes of secondary geochemical dispersion in the overburden. With this insight, additional experiments will improve the potential for understanding and refining current geochemical exploration techniques and for developing new techniques. During the fall of 1988 the Branch of Geochemistry, U.S. Geological Survey received drill core from Santa Fe Pacific Minerals, Inc., Reno, Nevada. The samples of core were obtained during the drilling of a hole through 460 ft (140 m) of alluvium to the southeast of the sedimentary rock- hosted Rabbit Creek Gold Deposit, but within the proposed pit design (fig. 1.). The post-mineralization alluvial core was obtained to characterize the distribution of elements in the overburden using a variety of analytical techniques. The 21 3-in-diameter core samples varied from 3 to 9 in in length and were taken, approximately, at 20-ft intervals. The first sample was taken at a depth of 15 ft and the last at 449 ft. The core samples were prepared for shipment in such a way the moisture loss and degradation to the integrity of the core was minimized. Upon arrival at the USGS laboratory facility in Denver, Colorado the samples were unpacked, described, and the samples were then physically prepared for analysis. Sample preparation The 21 core samples were air dried and weighed (table 1). The samples were then disaggregated in a soil machine consisting of a rotating ceramic auger and bowl. The sample is placed in the ceramic bowl and the auger is lowered gently to break-up aggregate grains. Large clasts were removed as they were freed in order to reduce the amount of chipping and breaking of the coarser fragments and allow the rotatory action to break up smaller aggregate grains. After disaggregation the samples were weighed again (table 1). The samples were then sieved into seven fractions using a Rototap Sieve Shaker with a running time of 20 minutes per sample, sieve fraction weights were recorded (table 1). The nested sieves produced sieve fractions of: +4 mesh, -4/+8 mesh, -8/+20 mesh, -20/+60 mesh, -60/+100 mesh, -100/+250 mesh, and -250 mesh. Splits of the -20/+60 and -60/+100 mesh fractions were processed further in a vertical pulverizer using ceramic plates where the splits were ground to approximately -100 mesh, these splits were used for chemical analysis. Two of the sieve fractions, -20/+60 and -100/+250, were processed to produce three heavy-mineral-concentrate fractions based on the specific gravity and magnetic susceptibility of the individual mineral grains. Twenty grams of sample were placed in separatory funnels filled with bromoform, a liquid with a specific gravity of 2.89. Lighter minerals, such as quartz and feldspar with specific gravities less than 2.8, will float in bromoform while heavier minerals will sink and can be easily removed. The heavy-mineral- concentrate samples were washed with acetone and air dried. The heavy-mineral concentrate resulting from the bromoform separation, was subjected to magnetic separations using a modified Frantz Isodynamic Separator to provide three magnetic splits of the sample: (Cl) strongly magnetic minerals, primarily magnetite, ilmenite, and mixed grains containing magnetite; (C2) weakly magnetic minerals, including most of the iron and
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manganese oxides and the ferromagnesian silicates; and (C3) very weakly to nonmagnetic minerals, primarily zircon, apatite, barite, and sphene but also including many ore-related sulfides and oxides. These magnetic separations are the same separations that would be produced by using a Frantz Isodynamic Separator set at a slope of 15 and a tilt of 10 with a current of 0.2 ampere to remove the magnetite and ilmenite (Cl), and a current of 0.6 ampere to split the remainder of the sample into weakly magnetic (C2) and "nonmagnetic" (C3) fractions. Each of the fractions was weighed and the results are compiled in tables 2 and 3. Clast samples were picked from the plus 4 mesh sieve fraction. Individual clasts were picked from samples for specific characteristics. These clasts were treated as a separate sample medium where a variety of descriptive and analytical techniques were employed to characterize them. Explanation of Data The data are presented by laboratory methodology or analytical treatment of the sample. There are 14 data sections including: core description, mineralogy, X-ray diffraction, sequential digestions, cold-vapor atomic absorption spectrophotometry, visible-absorption spectrophotometry, ion specific electrode, flame atomic-absorption spectroscopy, arsenic determinations, gold determinations, gas chromatography, and emission spectrography total and oxalic partial. In each section, data generated by a specific laboratory treatment are presented for all samples tested. An explanation describing the technique used and the format of the data presentation is provided for each of the 14 sections. Core Description We received 21 samples of alluvial core, each sample 3-9 in long, from core hole 313A at the site of the Rabbit Creek gold deposit. The samples were wet and wrapped in aluminum foil when received. They were allowed to dry for several days, before being examined. The visual examination was done with a hand lens and a binocular microscope. It consisted of a brief description of the content, shape, and proportions of the clasts, as well as the degree of induration, nature of matrix, presence of cementing medium, and color of the core. The color was described by using a standard soil color chart (see table 4). Following the visual examination, pieces of core were acidified by placing the sample in a beaker of 1:4 HC1 and the nature of the reaction was described. After acidification of each sample, the finer grained material was decanted during several successive washings and the presence of quartz and other minerals of the sand-size fraction was briefly noted. Two pieces of each sample were submitted to make thin sections. Some of the thin sections were very hard to make, because of the varying degrees of induration of the core samples, some of which were very weakly indurated. The descriptions of thin sections are shown in table 5. Questionable minerals that were not identified in thin section were identified by X-ray diffraction. The remainder of the core samples was disaggregated and sieved in preparation for studies of grain-size distribution, mineralogy, and geochemistry of the various sieve fractions.
TABLE 2 HEAVY MINERAL CONCENTRATE WEIGHTS -100/+250 FRACTION SAMPLE f TOTAL WT. (g)
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(9) CONC. WT. (g) PERCENT HEAVIES TABLE 3 HEAVY MINERAL CONCENTRATE WEIGHTS -20/+60 FRACTION SAMPLE # TOTAL WT. (g) (9) (9) (9) CONC. WT. (g) PERCENT HEAVIES
Grain-size analysis was done by constructing cumulative curves from data points produced by sieving with the Rototap Sieve Shaker. Additional size fractions were generated by further hand sieving of the coarsest material (+4 mesh, +4.75 mm), which represented more than 40 percent of the weight of many samples. The additional size fractions are as follows: +50 mm, +45 mm, +31.5 mm, +25 mm, +19.1 mm, +12.7 mm, and +9.52 mm. The hand-generated sieve data are shown in table 6. The additional data points were used to construct the coarse end of the cumulative curves and to better determine graphic percentiles by inspection of the curves. Linear combinations of the percentiles were used to calculate graphic statistical parameters of grain size. From three to five percentiles were used in each calculation, because generally the accuracy of the statistical values is determined by the number of percentiles used. The parameters that were calculated by the graphic method are graphic mean grain size, graphic standard deviation, inclusive graphic skewness, and graphic kurtosis (Folk, 1980). The selected percentiles and calculated parameters are listed in table 7. We studied the +4-mesh pebbles and cobbles separately. We sorted them by lithology with the aid of binocular and petrographic microscopes and X-ray diffraction of selected clasts. The various clast types then were weighed to determine the percentage by weight of each clast type in each sample.
Table 4. Descriptions of hand samples of alluvium from core at the Rabbit Creek gold deposit Sample Number; Size and Depth of Core Sample; 9 in at 15 ft. Name; Sandy conglomerate with calcite cement, probably greater than 10%. Color; Light tan/grey Hue 10 YR 8/3. General Description; Very poorly sorted. Matrix is largely sand sized material, not much in the way of fine silt or clay sized material. The interior of the segment contains voids that are clustered around the pebbles. Maximum dimension of spaces about 4 mm. Well indurated, but still friable. Clast Characteristics; Clasts are subangular and subrounded with a maximum size of about 5 cm. There are numerous small, white, rounded, and subrounded clasts - tuff, with biotite crystals and small rock fragments, or perhaps clasts of caliche with black, volcanic glass. Perhaps 5% by volume, with a maximum size of about 1 cm. Clasts defined by size greater than 2 mm. Character of Matrix; Sand size material mostly, 2 mm to about 1/20 mm. Matrix has a carbonate cement. After acidification, matrix is porous. Reaction with HC1 (1:4): Strong. Description of sand and silt-size matrix mineralogy; Dominantly quartz, rock fragments, iron oxides, some muscovite, feldspar, biotite, and hornblende(?). Other; Very strong diesel odor - probably from water-soluble oil used in drilling fluid. All of the core samples have this smell. Sample Number; 2. Size and Depth of Core Sample; 8 in at 38 ft. Name; Sandy conglomerate with calcite cement greater than 10%. Color; Light tan/grey HUE 10 YR 8/2. General Description; Very poorly sorted and strongly indurated. Segment contains voids throughout. The voids are up to 5 mm in longest dimension. Estimate about 10% porosity due to these voids. Induration due to cementation by calcite. Clast Characteristics; Clasts angular to subrounded, with maximum size up to 6 cm. These are matrix supported and estimated to make up about 20% to 25% by volume (+2 mm size). Just a few tuff (or caliche?) clasts as seen in sample number 1. Character of Matrix; Sand size mostly, to coarse silt. Range is about 2 mm to about 1/50 mm. A very fine grained, granular calcite cement is present in the matrix. Reaction with HC1 (1:4): Very strong. Description of sand- and silt-size matrix mineralogy; Dominantly quartz, rock fragments, and iron oxides with some biotite flakes and sphene(?). Quartz approximately equivalent to rock fragments. Quartz grains strongly iron-oxide coated. Other; Induration is so hard that some clasts break when rock is hit with a hammer, rather than disaggregate from the matrix. Sample Number; 3. Size and Depth of Core Sample; 9 in at 59.5 ft. Name; Sandy conglomerate with calcite cement greater than 10%. Color; Light tan/grey Hue 10 YR 8/3. General Description; Very friable, disaggregated while sitting around. Poorly sorted. Clast Characteristics; Clasts are subangular and subrounded with +2 mm making up about 30% to 40% by volume, possibly 50%. Matrix supported where more cohesive, but cannot be certain about the naturally disaggregated parts of sample. Clasts are up to 3 cm maximum size. Character of Matrix; Mostly sand size, 2 mm to 1/50 mm. There are some white clots of calcite cement up to 3 or 4 mm across. Limonitic clots up to about 1 cm across are also present. Reaction with HC1 (1:4): Very strong, in spite of the poor induration. Description of sand- and silt- size matrix mineralogy; Dominantly quartz, with iron oxides, biotite, rock fragments, and some muscovite.
Sample Number: 4. Size and Depth of Core Sample: 7 in at 83.2 ft. Name: Sandy (tuffaceous) conglomerate, with calcite cement greater than TOST Color; Light grey/tan Hue 2.5 YR 8/1. General Description; Poorly sorted, indurated but moderately friable. There are irregular open spaces or voids with maximum dimension about 1 cm. There are tuffaceous (or caliche?) clasts and layers, subparallel to the core diameter, which partially wrap around clasts. Clast Characteristics; Clasts subangular and subrounded, majority are subrounded. Maximum size to about 2 cm, makeup about 25% to 30% by volume - matrix supported. Tuffaceous clasts present. Character of Matrix; Mostly sand with abundant calcite cement, but the friability (hence cementation) vary. There are some very "rock like", far more indurated parts of this sample, which suggests irregular distribution of the calcite cement. Disaggregation was not complete with acid, which probably means some other cementation medium, such as silica or sulfates, is present. Reaction with HC1 (1:4); Very strong, but again, as above, disaggregation was not complete. Description of sand- and silt-size Matrix Mineralogy; Sand-sized material is mostly quartz, with iron oxide grains, feldspars, some muscovite, biotite, epidote(?), garnet, and hornblende. Other; Tuffaceous matrix (white) is more common this segment than in the higher samples, but it also has an abundance of calcite. It is not crumbly caliche, but tuffaceous material as it includes a lot of biotite and quartz crystals in it - similar to the smaller tuff (or caliche?) clasts. Perhaps it represents smeared-out larger tuff (or caliche?) clasts. Sample Number: 5. Size and Depth of Core Sample: 9 in at 107 ft. Name; Sandy breccia with calcite cement greater than 10%. Color; Light grey/tan Hue 2.5 YR 8/1. General Description; Very poorly sorted, large clasts, very hard, and well indurated (almost a rock). There is considerable vug or pore space between grains in spite of dense cementation. Clast Characteristics; Clasts angular and subangular up to 7 cm, maximum dimension. Due to angularity, this is more of a breccia. Some well indurated tuffaceous (or caliche?) clasts to 1 cm, which contain biotite and quartz crystals up to 1 mm size. Numerous large clasts in this segment. Clast proportion about 50%, matrix supported. Character of Matrix; Sandy to tuffaceous, probably some calcium carbonate. Abundant granular carbonate cement gives matrix a vitreous lustre. Small white clots appear to be caliche patches - irregular, very fine grained. Reaction with HC1 (1:4): Very strong, but disaggregation incomplete, so may be some silica or sulfate cement as well. Description of sand- and silt-size matrix mineralogy: Quartz, with iron-oxide aggregates and grains, rock fragments, epidote(?),hornblende(?), possibly some fluorite. Other; Sample would be very hard to disaggregate. Sample Number; 6. Size and Depth of Core Sample: 7 in at 124 ft. Name; Sandy conglomerate with calcite cement greater than 10%. Color; Light grey/tan Hue 2.5 YR 8/2. General Description: Very poorly sorted, hard, well indurated, but disaggregates easier than previous sample. Clast Characteristics; Angular and subangular clasts make up about 20 to 30% by volume, with maximum size to about 5 cm. Matrix supported. Some clasts are tuffaceous (or caliche?) up to about 2 cm in size. Some carbonate clasts have caliche rims up to 3 mm thick, which are banded. Character of Matrix: Sandy mostly, with a abundant calcite cement. Reaction with HC1 (1:4); Strong, but disaggregation not complete, so may contain silica or sulfate as well as calcite. Description of sand- and silt-size matrix mineralogy; Dominantly quartz, with rock fragments, iron oxides as aggregates and single grains, hornblende, minor biotite.
Sample Number; 7. Size and Depth of Core Sample: 7 in at 149 ft. Name: Sandy conglomerate with calcite cement greater than 10 percent. Color; Light tan Hue 2.5 Y 8/1. General Description; Very poorly sorted, well indurated. A clot of organic(?) material about 1-2 cm wide, l-2cm thick, parallel with core diameter, having a resinous luster, containing sand grains, forms part of the matrix. Matrix also has smaller clots of similar character. The segment contains voids, in spite of being well cemented. Clast Characteristics; Angular and subangular up to 6 cm, most considerably smaller makeup 20 to 30% by volume, matrix supported. Some tuffaceous (or caliche?) clasts with biotite and quartz phenocrysts up to 3 cm across. Character of Matrix; Sand, mostly with carbonate cement. Caliche and hyalite (secondary, clear silica) also present. Reaction with HC1 (1:4): Strong. Description of sand- and silt-size matrix mineralogy; Mostly quartz, followed by rock fragments and iron oxide aggregates and grains, feldspar, minor epidote(?). Organic clots of sand size with smaller grains. Other; The resinous, organic(?) clot is brownish. Fractures in large clasts and matrix boundaries with clasts contain caliche and hyalite. This was the only noted occurrence of silica in matrix/fractures seen in the core segments. Sample Number; 8. Size and Depth of Core Sample: 8 in at 176 ft. Name; Sandy conglomerate with calclte cement greater than 10%. Color; Light tan/yellow Hue 10 YR 8/3. General Description; Very poorly sorted, well indurated, and clast rich (almost a rock).The segment looks porous, but does not have large voids seen previously. Clast Characteristics; Clasts subangular and subrounded, estimate 30 to 40% by volume, greater than 2 mm, in sandy matrix. Maximum size to 6 cm. Tuff (or caliche?) clasts with quartz, biotite and garnet crystals are present, up to about 1 cm size. Character of Matrix; Sandy, mostly with a calcite cement. Reaction with HC1 (1:4): Strong. Description of sand- and silt-size matrix mineralogy; Dominantly quartz and iron oxides - euhedral magnetite crystals present. Some possible tourmaline, epidote(?) and hornblende(?). Sample Number; 9. Size and Depth of Core Sample: 6 in at 201.8 ft. Name; Sandy conglomerate with calclte cement greater than 10%. Color; Light tan/grey/brown Hue 7.5 YR 8/3. General Description; Poorly sorted - moderately and variably induratedL Clast Characteristics; Clasts subangular and subrounded, maximum size up to 6 to 7 cm, most much smaller. A few tuffaceous (or caliche?) clasts, generally less than 1 cm in size, some smaller elongate clots of this material. Character of Matrix; Sandy matrix, carbonate cement visible as fine-grained vitreous interstitial material. Reaction with HC1 (1:4); Strong. Disaggregation not complete with acid, indicates silica and/or sulfates present as well as calclte in the cement. Description of sand- and silt-size matrix mineralogy; Quartz with abundant feldspars; hornblende, epidote(?), biotite, and feldspars more common than in previous samples. Iron oxides. Sample Number; 10. Size and Depth of Core Sample: 6 in at 224 ft. Name; Sandy conglomerate with cement greater than 10%. Color; Tan/yellow Hue 10 YR 8/4 more of a limonite color than previous. General Description; Poorly sorted, very pebbly; contains large amounts of tuff (or caliche?) clasts and the smaller clasts are distinctly rounded. Relatively friable in comparison with higher samples. Clast Characteristics; Clasts subangular and rounded up to 3.5 cm. Most of the smaller ones distinctly round. The clasts are 40 to 50% by volume. Tuff (or caliche?) clasts are common, and relatively
rounded in comparison with other clast types. They contain biotite (or black volcanic glass?) and lithic fragments - of variable composition. Carbonate clasts which are present have no caliche overgrowths. Character of Matrix; Sandy, but with more fines than previously seen. Size ranges from 2 mm to 1/100 mm. Reaction with HC1 (1:4); Strong, and produced cloud of fines, more so than previously seen in higher samples. Description of sand- and siIt-size matrix mineralogy: Dominantly quartz, iron oxides, and rock fragments. Iron oxides include magnetite. Rock fragments and feldspars common. Some hornblende. Other; Although the matrix is dominantly sandy, there appear to be more clays within it than previously described. Sample Number; 11. Size and Depth of Core Sample; 9 in at 249 ft. Name; Sandy conglomerate with calcite cement greater than 10%. Color; Light tan/grey Hue 10 YR 8/2. General Description; Poorly sorted, well indurated. Clast Characteristics; Clasts subangular and subrounded up to 5 on size, matrix supported, make up about 40% by volume of the rock. Numerous tuff (or caliche?) clasts present, to about 1 cm in maximum dimension. Character of Matrix; Sandy; vitreous carbonate cement in matrix. Common, clear, equant, striated grains about 1 mm in size occur in matrix. These are probably calcite, as they disappear on acidification. Matrix size 2 mm to 1/50 to 1/100 mm; fines present but not much below silt (as usual). Reaction with HC1 (1:4): Strong. Description of sand- and silt- size matrix Mineralogy: Dominantly quartz with minor iron oxide aggregates and single grains. Magnetite present. Some quartz grains are very well rounded. Some rock fragments. Other; The striated crystals, tentatively identified as calcite, might be salt (NaCl) as they appear to have a very salty taste. However, the taste could be from material in the matrix. The crystals are soft and dissolved on acidification. In this particular specimen they also appeared to disappear when water was poured on the sample. This was not the case for some lower samples. Sample Number; 12. Size and Depth of Core Sample: 7 in at 275 ft. Name; Sandy conglomerate with calcite cement greater than 10%. Color; Light tan/grey Hue 10 YR 8/1, but variable to 8/4; areas of carbonate cement are lighter. General Description; Indurated but relatively friable. The sandy matrix contains some irregular voids, which are 2 to 3 mm in maximum dimension. Some Mn-oxides present on what appears to be internal fractures in the segment. Clast Characteristics; Clasts are subangular and subrounded up to about 5 cm size and makeup about 30% by volume. Matrix supported. One large limonite clast brokeup, about 2.5 on; may represent oxidized organic material? Character of Matrix; Sandy, mostly, but down to about 1/50 mm, some even smaller. Calcite cement is present, smooth looking, interstitial; however, not evenly distributed. Reaction with HC1 (1:4): Very strong. Description of sand- and silt-size matrix mineralogy; Dominantly quartz and feldspar, and iron oxides. Common euhedral magnetite. Other; Induration is variable as the calcite cement is not uniform throughout the segment. The calcite rich zones are the hardest. Sample Number; 13. Size and Depth of Core Sample; 6 in at 299 ft. Name; Sandy conglomerate with calcite cement greater than 10%. Color; Light tan/ye How/grey Hue 10 YR 8/3. General Description; Variably indurated, poorly sorted. Evidently the calcite cement is again variable in the segment. Lots of internal porosity, particularly open spaces around the pebbles up to 1 cm maximum dimension. Some equant voids 3 mm across. Clast
Characteristics: Clasts subangular and subrounded up to 5 cm across makeup 30 to 40% by volume. Matrix supported. Tuff (or caliche?) clasts present up to about 1 cm across. These contain biotite (or black volcanic glass?). Character of Matrix; Sandy, with interstitial carbonate cement which gives a resinous lustre. Again, glassy crystals present in matrix in clusters which disappear when wet and have a weak salty taste. Could these be halite, or calcite? Reaction with HC1 (1:4); Very strong. Disaggregation not complete on acid; probably some silica and or sulfate in cement. Description of sand- and silt-size matrix mineralogy: Dominantly quartz, quartz-aggregates and rock fragments. A few very rounded quartz grains, magnetite, and other iron- oxide grains. Lots of iron-oxide stain on quartz and aggregate quartz grains. Sample Number: 14. Size and Depth of Core Sample; 6 in at 323 ft. Name; Sandy conglomerate. Color; Tan/yellow Hue 10 YR 8/6, but with limonitic splotches up to about a cm in size. General Description; Poorly sorted, coherent, but generally friable. Matrix has large amount of limonite and hematite stained spots. Clast Characteristics; Clasts subangular or subrounded, up to about 3 cm; matrix supported. These makeup about 30% to 40% by volume of the sample. Tuff (or caliche?) clasts present, but sparse. Probably contained biotite, now FeOx spots. Character of Matrix; Sandy, but with lots of limonite and hematite stain. Very fine grained silty and clay- rich aggregates, limonitic and hematitic zones occur in it. Reaction with HC1 (1:4); None. Description of sand- and silt-size matrix mineralogy; Dominantly quartz with feldspar, rock fragments, and iron oxides, including magnetite grains. Other; First sample with no carbonate matrix. Sample Number; 15. Size and Depth of Core Sample; 8 in at 342 ft. Name; Sandy, silty(?), conglomerate.Color;Mottled, tan/brown/yeHow Hue 10 YR 8/4 to 10 YR 6/8, very variable. General Description; Poorly sorted, fairly friable. Has lots of limonitic and hematitic mottling. Some hematitic material probably oxidized clasts. Clast Characteristics; Clast subangular and rounded, many rotten and friable, up to 3 cm and make up 30% to 40% by volume. Matrix supported. Some small tuff (or caliche?) clasts, fairly common. Some of these clasts are smeared out and bent around adjacent pebbles of harder material. Character of Matrix; Sandy but appears to have more fines than previously noted. Hematitic and limonitic zones as noted above. Reaction with HC1 (1:4); None, however, the sample disaggregated to produce a large cloud of fine material and a coarser residue. The cloud of fine material was floated off. Description of sand- and silt-size matrix mineralogy; Dominantly quartz, feldspar, and iron oxide grains with large of magnetite fraction. Aggregate limonite and hematite and rock fragments (these may be same thing). Sample Number; 16. Size and Depth of Core Sample: 7 in at 361 ft. Name; Sandy, silty conglomerate with calcite matrix greater than 10%. Color; Upper 7.5 YR 8/2 light tan/grey, lower 10 YR 8/3 light tan/yeHow/grey. General Description; Poorly sorted and variably indurated. Top 2/3 is rock like, bottom 1/3 is friable due to differences in cementation. Clasts also larger and sparser at top. Clast Characteristics; Upper clasts subangular and subrounded to 5 cm size, larger and sparser than the subrounded lower ones. Overall about 30% of rock is clasts, matrix supported. Tuff (or caliche?) clasts present, to about 1 cm in size. Character of Matrix; Upper part sandy to tuffaceous with carbonate cement,
lower is sandy. Clay clots occur in the sand fraction. Limonitic and hematitic splotches occur in the matrix of the lower part, as described for other samples above this zone. Reaction with HC1 (1:4): Variable. Stronger for upper part but still had reaction for lower as well. Acidification produced a cloud of fine material, which was decanted, and a coarser residue. Description of sand- and silt-size matrix mineralogy: Dominantly quartz with iron oxides and rock fragments. Some magnetite in the iron oxide fraction. Other; This segment shows variation in just 7 in, with very different induration characteristics due to differing amounts of carbonate cementation. Some variations in degree of cementation have been noted in samples from higher in the section as well. Sample Number; 17. Size and Depth of Core Sample; 9 in at 380 ft. Name; Sandy conglomerate with calcite cement, less than 10% (?). Color; Variable; Tan/yellow/grey 10 YR 8/4 to 7/4. General Description; Well indurated, but variably so. Poorly sorted. Flatter clasts show an imbrication, parallel to the core diameter. Color is mottled again due to limonitic rich clots and zones. Clast Characteristics; Subangular and subrounded clasts up to 6 cm size make up 30% to 40% of the segment and are matrix supported. A few tuff (or caliche?) clasts are present. Character of Matrix; Mostly sandy, but with mottled, hard limonitic zones or clots. No distinctly obvious carbonate cement. Reaction with HC1 (1:4): Variable, moderately strong in places. Description of sand- and silt-size matrix mineralogy; Sand fraction dominantly quartz with rock fragments and iron oxides, a good deal of which is magnetite grains. Some aggregate iron oxides which may be oxidized rock fragments. Lots of clear feldspar and some muscovite, noted also sphene, epidote(?) or pyroxene(?). Sample Number; 18. Size and Depth of Core Sample; 8 in at 402 ft. Name; Sandy, silty conglomerate with greater than 10% calcite cement. Color; Mottled, light brown to reddish brown due to hematitic splotches and clasts, Hue 10 R 4/8 (red splotches), 10 YR 8/4 to 8/8 other areas. General Description; Poorly sorted, well indurated but still relatively friable. Lots of hematitic splotches and clasts. Voids are abundant, particulary along boundaries of clasts and matrix. Voids have maximum dimension of 1 cm. Clast Characteristics; Clasts subangular and subrounded, maximum size to 6 cm, matrix supported, makeup 40% of segment. Some of the hematitic zones are actually clasts, up to about 4 mm size. Some tuff clasts, up to about 1 cm size, that contain magnetite. Estimate hematite zones to be about 10-15%. Character of Matrix; Sandy mainly but particle size down to 1/50 to 1/100 mm. Some hematitic areas in matrix are clayey. Estimated 10 to 15% hematitic zones. This segment has a lot of iron. Reaction with HC1 (1:4): Very strong (and unexpected, as matrix was not obviously carbonate cemented). Dissolution gave a lot of fines which were decanted. Description of sand- and silt-size matrix mineralogy; Mostly quartz and quartz-aggregate rock fragments, iron oxide grains, with some magnetite. Some quartz very rounded. Other; Voids around some of the clasts are filled with clear, striated crystals. Possibly halite again, as they taste a bit salty. This material was included in the thin section blank. It did fizz on acidification, which suggests that the material is really calcite or that there is calcite around these crystals that is producing the fizz. The crystals did not completely disappear when acidified. Another possibility is that these crystals are gypsum.
Sample Number; 19. Size and Depth of Core Sample; 8 in at 421 ft. Name; Sandy conglomerate with calcite matrix greater than IQ% (?). Color: Tan to reddish yellow. Hue 10 YR 7/4 to 10 R 4/8. General Description; Poorly sorted, indurated, but relatively friable. Matrix again has hematitic zones, but not as many as previously. Distinctly full of voids, with open spaces around the pebbles and more equant than previous sample. Again, lined with clear striated crystals, which could be either halite, gypsum, or calcite. Clast Characteristics; Very clast rich; subangular and rounded, about 40# by volume perhaps as high as 50; matrix supported. Maximum clast size 5 cm. Hematitic clasts probably less than 5%. Tuff (or caliche?) clasts present, largest to 1 cm, most are smaller. Character of Matrix; Sandy, same approximate size distribution as before. Reaction with HC1 (1:4): Moderately strong. Acidification produced a heavy cloud of fine material, although not as much as in some of the higher samples, and also a coarser residue. The finer material was decanted. Description of sand- and silt-size matrix mineralogy; Mostly quartz, with feldspar, quartz aggregate rock fragments, iron oxides, with a lot of magnetite which is generally pretty fine grained. Some large clear quartz crystals. Sample Number; 20. Size and Depth of Core Sample: 3 in at 422 ft. Name; Moderately poorly sorted, epiclastic, medium-fine grained sand. Color; Tan/yeHow/brown, Hue 10 YR 8/3 to 8/4. General Description; A sandy zone, continuous with the last segment. Moderately poorly sorted, well indurated sand. Character of Matrix; Grain size of sand approximately 0.5 mm to 1/50 to 1/100 mm. Some 1 mm tuffaceous (or caliche?) clasts, rounded, some rock fragments in coarser fraction as well. Magnetite rich. Reaction with HC1 (1:4); None, but lots of fines were produced by solution which were decanted. Description of sand- and silt-size matrix mineralogy; Sand is mostly quartz or quartz-feldspar aggregates, stained with iron oxide, and containing fine magnetite. Just a few discrete quartz crystals and sand-sized rock fragments, largely quartz aggregate or quartzite. Some magnetite crystals. This may be a reworked tuff with some fine material present. Other; In thin section, check for shards. The aggregate texture of the grains and their fine dusting of magnetite suggests tuff. Sample Number; 21. Size and Depth of Core Sample: 6 in at 449 ft. Name; Tuffaceous conglomeratic sand, fine to medium grained. Color; Light brown/yellow 10 YR 8/6. General Description; Poorly indurated, relatively friable, sandy conglomerate. Clast Characteristics; Clasts are angular and subrounded, up to about 6 cm, forming 20% by volume, matrix supported. One large clast is a fine grained, well indurated tuff (or caliche?) fragment. About 5% to IQ% hematitic clasts and clots. Few clasts are below 5 mm in size; which differs from previous samples. Character of Matrix; Sandy, much like the sand of the previous sample. Size range about 0.5 mm to 1/50 to l/100mm. Much iron oxide dusting (mgt. ?). Reaction with HC1 (1:4): Very slight. Lots of fines produced by fluid which were decanted. Description of sand- and silt-size matrix mineralogy; Mostly quartz aggregate probably quartz-feldspar aggregate, some individual quartz crystals, lots of magnetite. Again, this resembles tuffaceous material and should be checked for shards.
Table 5. Descriptions of thin sections and polished sections. Sample 1 (Depth, 15 ft) Deformed, quartz-rich rock containing small clasts 0.5mm) of chert?, silicified rocks veined with quartz, metamorphic rocks that are mica rich, and basalt. Most clasts lack distinct boundaries. The rock contains veins of cockscomb- text ured quartz with vague boundaries. Sample 2 (Depth. 38 ft) Slide 1 Matrix- and cement-supported conglomerate containing rock fragments (many are +1 cm) and mineral grains floating in a matrix of very fine grained calcium carbonate, quartz, and feldspar. The composition of the matrix was confirmed by x-ray diffraction analysis. Rock fragments include limestone, metamorphic rocks (0.5 mm), and basalt (0.3 mm); mineral grains include angular quartz (0.2 mm), angular plagioclase (60ym), biotite, white mica, and opaque minerals. Clasts of limestone consist of fossil crinoid columnals with rim cement (40-50% of the rock), pelloids, endothyrid forams, scraps of Bryozoa, silt- sized quartz, and possibly fragments of chert, all cemented with sparry calcite. The constituents listed above suggest that this limestone was deposited in shallow water. Evidence for solution compaction can be seen along some calcite grain boundaries, where the rim cement surrounding crinoid stems has been dissolved and grains have compacted together. Slide 2 Cement- and matrix-supported conglomerate with rock fragments and mineral grains floating in sand- to clay-size matrix of very fine grained calcium carbonate, quartz, and feldspar. The rock fragments include detrital caliche (>1 mm), metasedimentary rocks (>1 mm), siltstone, silicified rocks with faint foliation, some intensely foliated metasedimentary rocks, and altered basalt (0.5 mm); mineral grains include quartz (100pm), plagioclase (including AnJ, hornblende, calcite, and clinopyroxene. Sample 3 (Depth, 60 ft) Clast- and matrix-supported conglomerate containing rock fragments (+l-cm size) floating in sand- to clay-size matrix and calcium carbonate. The rock fragments include metamorphic rocks (>1 mm), basalt with plagioclase micro! ites, detrital caliche, calcareous siltstone containing fine-sand-sized angular quartz (200ym) and pelloids, limestone with detrital quartz (50ym), recrystallized quartzite, limestone with coating of caliche, and silicified limestone. Mineral grains include rounded (reworked) quartz (300pm), strained quartz, plagioclase, and opaque minerals. Interstitial material between the +l-cm rock fragments is very fine grained calcium carbonate cement. A clast of silicified rock contains a cross section of a silicified crinoid columnal, proving that the rock is a silicic alteration of limestone rather than a true chert.
Sample 4 (Depth. 83 ft) Mixture of local clast-supported (clasts +1 cm) and local matrix- and cement-supported conglomerate containing rock fragments of basalt with fresh plagioclase microlites, recrystallized quartzite, igneous rock containing epidote, detrital caliche, micaceous metasedimentary rock, and limestone. Mineral grains include quartz, plagioclase, hornblende, and epidote. Clasts of detrital caliche are soft and have been deformed around harder clasts of limestone. The cement is very fine grained calcium carbonate (caliche). Sample 5 (Depth. 107 ft) Slide 1 Clast-supported conglomerate contains rock fragments (+0.5 cm) of caliche-coated limestone (with detrital quartz grains that are SOOym), detrital caliche, basalt with microlites of calcic plagioclase(composition of Ang3_yo), foliated metasedimentary rocks, recrystallized quartzite, serpentinite?, and silicified rocks. Mineral grains include quartz, clinopyroxene, hornblende, plagioclase, calcite, mica, and opaque minerals. Interstitial caliche, fine-grained rock fragments, and mineral grains are matrix and cement. The coatings (0.5mm) of caliche on various larger rock clasts are distributed asymmetrically, such that the coating is thicker on one side of a clast than on the other side. Slide 2 Clast-supported conglomerate contains rock fragments of limestone, basalt, metasedimentary rocks, silicified and quartz-veined rocks, and ultramafic rocks containing clinopyroxene, orthopyroxene, and serpentine. Mineral grains include quartz, plagioclase, orthopyroxene, hornblende, white mical, and glass shards. Interstitial calcium carbonate is probably the cement. Sample 6 (Depth. 124 ft) Mixture of local clast-supported (clasts +4 cm) and matrix- and cement- supported conglomerate in fine sand matrix of mineral grains and fine-grained rock fragments. Conglomerate contains caliche-coated rock fragments of limestone, calcareous siltstone, metasedimentary rocks, basalt, detrital caliche, and silicified rocks. Mineral grains include quartz, plagioclase, and hornblende. Cement is probably a secondary calcium carbonate. Some limestone clasts contain fossils, including crinoids that are surrounded by rim cement, endothyrid forams, fusulinids, and echinoid spines. Locally, crinoids contain the mud-filled borings of endolithic algae, which indicates that deposition occurred in the photic zone. The above constituents suggest shallow-water deposition of the original limestone unit. Sample 7 (Depth, 149 ft) Slide 1 Unusually well consolidated rock, which contains an abundance of silicic rock fragments. Clast-supported conglomerate contains fragments of recrystallized quartzite, si Itstone/mudstone, foliated metasedimentary rocks, and silicified rocks. Mineral grains include more angular quartz, rounded
(reworked) quartz (350ym), and goethite as a replacement of euhedral pyrite. The boundaries between clasts and cements are vague, so that the clasts are difficult to distinguish from cement in thin section. The cement is a coarse secondary calcium carbonate. The rock contains a vein of calcite and clusters of goethite pseudomorphs of euhedral, pyritohedral pyrite. Slide 2 Clast-supported conglomerate containing clasts of quartzite and siltstone/mudstone (300-1200pm). Mineral grains include quartz, and cement is probably a secondary calcium carbonate. Rock is veined by calcium carbonate and contains clusters of goethite. Polished section Goethite replacement of euhedral, pyritohedral pyrite (<0.1 mm).If the original euhedral pyrite was detrital, then it did not travel far, because the crystals show no effects of abrasion. Fresh and finely disseminated, relict pyrite (<4ym) occurs, some of which is pyritohedral in form. Saaple 8 (Depth. 176 ft) Slide 1 Clast-supported conglomerate containing rock fragments (+0.5 cm) of limestone, basalt, foliated metasedimentary rocks, detrital caliche, coarse-grained siltstone with quartz 125ym, limestone with detrital quartz silt (40ym), and silicified rock veined with quartz. Limestone clasts contain tangential sections of fusulinids and cross section of a spine (200ym) that is well preserved. Mineral grains include quartz, calcite, plagioclase, and hornblende. Matrix and cement are the very fine grained clays and calcium carbonate that occur interstitially. Slide 2 This sample is dominated by a large clast of what is a siltstone to fine-grained sandstone, which contains quartz grains 40-70ym. The largest clast is surrounded by a thick (1200ym) coating of caliche. Within the caliche coating there are well-preserved glass shards. The other clasts in the slide are smaller fragments of limestone, basalt with plagioclase microlites, very fine grained sandstone with quartz grains that are up to 50ym, angular glass shards (200ym), red chert, plagioclase (+240ym), quartz, and hornblende. Sample 9 (Depth. 202 ft) Slide 1 Clast-supported conglomerate containing rock fragments (+0.5 cm) of basalt, detrital caliche, igneous rock altered to chlorite, very fine grained sandstone with quartz grains 200ym, silty limestone (+2 mm) with quartz grains 40ym, serpentinite?, metasedimentary rocks with quartz grains 600ym, and quartz-veined siltstone. Interstitial material is more abundant than in sample 8, and consists of mineral grains of quartz, plagioclase, hornblende, and unidentified opaque minerals, and fine-grained rock fragments. The cement is caliche. Slide 2 Clast-supported conglomerate containing clasts of basalt with local clinopyroxene preserved, limestone, siltstone, metasedimentary rocks, silty limestone, silicified rocks, and detrital caliche. Mineral grains include quartz, plagioclase, hornblende, and opaque minerals, which are packed
together in the caliche cement with tiny rock fragments. The cement is secondary calcium carbonate (caliche). Sample 10 (Depth, 224 ft) Slide 1 Clast-supported, tightly packed conglomerate that contains clasts with very sharp boundaries, which are easily distinguishable in thin section. Clasts include limestone, siltstone with 60-ym quartz, metasedimentary rocks, some intensely foliated metamorphic rocks, detrital caliche, silicified rocks that are veined with quartz and calcium carbonate, and basalt. Mineral grains include very coarse, strained quartz, hornblende, and plucked-out material of unknown composition. The cement is calcium carbonate. A clast of very altered mafic volcanic/hypabyssal rock (>1 mm) contains a variolitic texture. Another clast of mafic volcanic/hypabyssal rock contains calcic plagioclase with a composition of Anyg. Slide 2 Clast-supported conglomerate with easily distinguishable clasts, as above. Clasts consist of fine-grained quartz-rich sandstone with rounded, second-generation, grains of quartz, partly silicified limestone, basalt, limestone, metasedimentary rocks, detrital caliche, completely silicified rocks, and siltstone. Mineral grains include quartz and plagioclase. Cement consists of equant grains of calcium carbonate. Saaple 11 (Depth. 249 ft) Slide 1 Clast-supported, tightly packed conglomerate containing clasts (+0.3 cm) of limestone, siltstone, metamorphic rocks, chert, basalt, silicified rocks, and detrital caliche. Locally cement-supported conglomerate. Locally, secondary calcium carbonate pushed apart rock fragments and/or filled open spaces. Mineral grains include quartz, fresh biotite, and hornblende. The cement is calcium carbonate. No halite was noted in thin section, although it was tentatively identified in hand sample. Slide 2 Clast-supported conglomerate containing clasts of calcite-veined siltstone, altered basalt, siltstone, detrital caliche, calcareous siltstone, limestone, silicified rocks veined with quartz, quartzite?, and metamorphic rocks. The rock appears to be clast supported and to lack obvious matrix or cement. Interstitial material may not have survived diagenesis or grinding and polishing of the thin section. Sample 12 (Depth. 275 ft) Slide 1 Cement- and matrix-supported conglomerate that contains clasts (+4 cm) of metamorphic rocks, veined and silicified rocks, chert, igneous rock consisting of plagioclase (800pm) and clay minerals, limestone (or caliche), and siltstone. Matrix contains sand-sized rocks and minerals, and caliche cement, which appears as calcite in the x-ray pattern. The slide is dominated by a large clast of siltstone. Clasts of the other lithologies occur adjacent to the siltstone clast.
Slide 2 Cement- and matrix-supported rock. The clasts include quartzite (or quartz siltstone), jasperoid, glass shards, limestone, altered bassalt or diabase, metamorphic rocks, and quartz in a cement of secondary calcium carbonate. Sample 13 (Depth. 299 ft) Clast-supported rock containing clasts (0.5-3.0 cm) of metasedimentary rocks, calcareous siltstone, quartzite with rounded grains of quartz that are up to 300ym, jasperoid or silicified rock, siltstone, altered mafic igneous rock (basalt?), and quartz-veined siltstone in cement of secondary calcium carbonate. Some clasts are coated with caliche, which is probably part of the detrital clast. Matrix consists of minerals and fine-grained rock fragments. No halite was noted in thin section. Saqjle 14 (Depth. 323 ft) Clast-supported, tightly packed conglomerate containing clasts of metamorphic rocks, rounded (reworked) clasts of basalt that consists of radial aggregates of acicular and fibrous minerals, coarser grained igneous rock with plagioclase that is 275ym, serpentinite?, siltstone, chert or jasperoid that is veined with quartz, quartzite (coarse), quartz, plagioclase, fresh brown biotite, and opaque minerals that are up to 1200 urn. The matrix is a green material that consists of clay (montmorillonite?) and quartz, as indicated by X-ray diffraction patterns. There is no obvious calcium-carbonate cement. Polished section Goethite occurs as a replacement of pyrite?, but there is no relict pyrite in the sample. The pyrite? replaced by goethite is not euhedral, as it is in sample 7. Instead, it is corroded or abraded. Sample 15 (Depth. 342 ft) Clast-supported, very tightly packed rock containing clasts (0.5-2.0 cm) of metamorphic rocks, siltstone, quartzite, basalt with micro!ites of calcic plagioclase (An 7*), jasperoid, only one limestone clast, quartz, plagioclase, and clay minerals?. There is no calcium-carbonate cement in this rock. X-ray diffraction analyses indicate that the interstitial material consists of clay minerals and quartz. The clay may be matrix material, or deformed and crushed fragments of an altered, labile rock. Sample 16 (Depth. 361 ft) Slide 1 Clast-supported conglomerate with interstitial fine-grained rocks and mineral fragments. Contains clasts of limestone, quartzite, siltstone, metamorphic rocks, jasperoid, quartz, plagioclase, biotite, and white mica in a cement of secondary calcium carbonate. Slide 2 Clast- and cement-supported rock containing clasts of limestone, siltstone, metamorphic rocks, micaceous quartzite, silicified rocks or chert, mildly foliated metamorphic rocks, altered volcanic rocks (basalt?), quartz, white mica, and calcite in a cement of secondary calcium carbonate.
Sample 17 (Depth, 380 ft) Clast-supported, tightly packed conglomerate with clasts (0.5-+3 cm) of siltstone, limestone, recrystallized quartzite or quartz- vein material, altered mafic igneous (basalt?) rocks, chert?, calcareous siltstone, metamorphic rocks, jasperoid?, quartz, plagioclase, and mica. Matrix consists of fine-grained rocks and mineral grains, in cement of secondary calcium carbonate. The basalt? contains the radial aggregates of acicular and fibrous minerals that are seen in other samples. Sample 18 (Depth. 402 ft) Clast-supported rock containing clasts (0.5-2+ cm) of limestone, altered basalt, siltstone, metamorphic rocks, chert?, and recrystallized quartzite or quartz-vein material. The interstitial material consists of quartz, calcium carbonate, and clay, according to x-ray diffraction analyses, and minor plagioclase appears in the thin section. Clasts of altered igneous rocks (basalt?) are particularly abundant in this sample. Siltstone clasts may be more abundant than metamorphic clasts. No halite was noted in thin section. Sample 19 (Depth. 421 ft) Clast-supported, very tightly packed rock containing clasts (<0.5-+1 cm) of metamorphic rocks, siltstone, silicified rocks or chert?, quartz-vein material, altered basalt?, minor limestone, quartzite, quartz, and biotite that shows only a pale pleochroism. Metamorphic rocks and siltstone are particularly abundant. There is no obvious matrix or cement. Neither halite nor gypsum were noted in thin section. Simple 20 (Depth. 422 ft) Matrix material, nearly opaque, Matrix contains tiny grains of quartz, silicified rocks (chert?), metamorphic rocks (125 ym), mica, and siltstone. No limestone observed. X-ray diffraction analysis indicates that the matrix material consists of quartz, impure calcite, and clay (montmorillonite?). Glass shards were not observed. Sample 21 (Depth. 449 ft) Clast-supported rock containing clasts (<0.5-+3 cm) of moderately foliated metasiltstone, altered basalt, metamorphic rocks, minor limestone or detrital caliche, slightly calcareous siltstone, jasperoid, volcanic glass?, and silicified rocks that may be recrystallized quartzite or quartz-vein material, clay, silt-sized quartz, and biotite. Siltstone and metamorphic rocks predominate in this sample. There is no calcium-carbonate cement in this sample. X-ray diffraction analysis indicates that the interstitial material consists of quartz and clay (montmorillonite?). The clay looks similar to that in sample 15. Glass shards were not observed in thin section.
Table 6. Weights of size fractions that were sieved by hand from the Rabbit Creek core samples [(--) denotes no data] Additional coarse sieve-fraction weights (g) Sample Core-sample +2" number description mesh +50 mm 9" 8" 9" 7" 9" 7" 7" 8" 6" 6" 9" 7" 6" 6" 8" 7" 9" 8" 8" 3" 6" Estimated at at at at at at at at at at at at at at at at at at at at at weighing error. 15' 38' 59.5' 83.2' 107' 124' 149' 176' 201.8' - 224' 249' 275' 299' 323' 342' 361' 380' 402' 421' 422' 449 ' ±0.01 +1 3/4" mesh +45 mm
29.0727.81
±0.01±0.01 , +1 1/4" mesh +31.5 mm
±0.01 +1" mesh +25.0 mm
±0
-l"/+3/4" +3/4" +1/2" mesh mesh mesh +19.1 mm +19.1 mm +12.7 mm
±0.01 ±0
±0.01 +3/8" mesh +9.52
-3/8"/+4 mesh mm +4.75 mm
Table 7. Selected percentlles and statistical parameters of grain size, Rabbit Creek core samples Statistical Sample number Core-sample length and depth 9" 8" 9" 7" 9" 7" 7" 8" 6" 6" 9" 7" 6" 6" 8" 7" 9" 8" 8" 3" 6" at 15' at 38' at 59.5' at 83.2' at 107 ' at 124' at 149' at 176' at 201.8' at 224' at 249' at 275' at 299' at 323' at 342' at 361' at 380' at 402' at 421' at 422 at 449' Percentiles (0) 1% 5% 16% 25% 50% (median) 75% 84% 95% Mean (0) Graphic Moment parameters Standard deviation (0) Graphic Moment Skewness Graphic Kurtosis Graphic The statistical parameters were determined from graphic measures (percentiles read from cumulative curves). In addition, the means and standard deviations were determined by moment measures, directly from sieve data (a computational rather than graphic measure). Where data were sufficient, the graphic parameters were based on three to five percentiles according to the method of Folk and Ward (1957) and Folk (1980). Where data were insufficient, the graphic parameters were determined from fewer percentiles according to the method of Inman (1952).
TABLE: 8 MINERALOGY OF THE -100/+250 FRACTION HEAVY MINERAL CONCENTRATE SAMPLE HMC SAMPLE # FRACTION DESCRIPTION BLACK W/ WHITE COATINGS TAN W/ WHITE COATINGS WHITE TO SANDY BLACK W/ WHITE COATINGS TAN W/ WHITE COATINGS WHITE TO SANDY W/ SCATTERED BLACK BLACK W/ WHITE COATINGS TAN W/ MINOR WHITE COATINGS
WHITE TO SANDY W/ SCATTERED BLACK BLACK W/ WHITE COATINGS TAN TO LT. GREEN W/ WHITE COATINGS WHITE COMMENTS EUHEDRAL, BLACK W/ THICK COATINGS EUHEDRAL GREEN "PRISMS" RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS BLACK, VITREOUS CLEAVAGE FRAGMENTS EUHEDRAL GREEN "PRISMS" PALE GREEN VITREOUS BROWN MICA CLEAR HEXAGONAL PRISMS DK. BROWN TO BLACK GRANULAR FRAGMENTS CLEAR TETRAGONAL PRISM BRASSY METALLIC CUBE EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS EUHEDRAL GREEN "PRISMS" RED, BROWN, AND YELLOW FRAGMENTS BLACK, VITREOUS CLEAVAGE FRAGMENTS BROWN, RED, AND EUHEDRAL BLACK MICA EUHEDRAL GREEN "PRISMS" PALE GREEN VITREOUS CUBE MILKY TO CLEAR PLATES CLEAR HEXAGONAL PRISMS AND ROUNDED GRAINS BROWN TO BLACK GRANULAR FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS BRASSY METALLIC CUBE YELLOW VITREOUS WEDGE BROWN MICA EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS EUHEDRAL GREEN "PRISMS" RED, BROWN, AND YELLOW FRAGMENTS EUHEDRAL GREEN "PRISMS" BLACK, VITREOUS CLEAVAGE FRAGMENTS PALE GREEN WAXY TO VITREOUS BLACK MICA CUBE PINK TETRAGONAL PRISM SILKY TO CLEAR HEXAGONAL PRISMS BROWN TO BLACK GRANULAR FRAGMENTS MILKY TO CLEAR PLATES VERY PALE GREEN GRAINS RED FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS EUHEDRAL, BLACK W/ COATINGS EUHEDRAL GREEN "PRISMS" RED FRAGMENTS EUHEDRAL GREEN "PRISMS" RED, BROWN, AND YELLOW FRAGMENTS BLACK, VITREOUS CLEAVAGE FRAGMENTS DK. BROWN TO BLACK MICA PALE GREEN WAXY TO VITREOUS MILKY TO CLEAR PLATES BROWN TO BLACK GRANULAR FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS BRASSY METALLIC CUBE YELLOW VITREOUS WEDGE BROWN MICA MINERAL IDENTIFICATION MAGNETITE PYROXENE - ENSTATITE FeOx FeOx AMPHIBOLE PYROXENE - ENSTATITE PUMPELLYITE BIOTITE APATITE APATITE - PHOSPHATE ZIRCON PYRITE MAGNETITE FeOx PYROXENE - ENSTATITE FeOx AMPHIBOLE BIOTITE PYROXENE - ENSTATITE PUMPELLYITE FeOx /PYRITE BARITE APATITE APATITE - PHOSPHATE ZIRCON PYRITE SPHENE BIOTITE MAGNETITE FeOx PYROXENE - ENSTATITE FeOx PYROXENE - ENSTATITE AMPHIBOLE PUMPELLYITE BIOTITE FeOx/PYRITE ZIRCON APATITE APATITE - PHOSPHATE BARITE PUMPELLYITE FeOx ZIRCON MAGNETITE PYROXENE - ENSTATITE FeOx PYROXENE - ENSTATITE FeOx AMPHIBOLE BIOTITE PUMPELLYITE BARITE APATITE - PHOSPHATE ZIRCON PYRITE SPHENE BIOTITE ESTIMATED ABUNDANCE 94Z 5Z 1Z 60Z 20Z 10Z 10Z RARE 80Z 20Z 1 GRAIN RARE 99Z 1Z RARE SOZ 20Z 10Z 10Z 10Z RARE 45Z 30Z 10Z 5Z RARE RARE RARE 10Z 1Z 40Z 35Z 15Z 5Z 5Z RARE RARE 69Z 15Z 10Z 10Z 5Z 1Z 89Z 10Z 1Z 55Z 20Z 15Z 5Z 5Z 94Z 5Z 1Z RARE RARE RARE MALLEABLE SILVER METALLIC BALLS & SLIVERS CONTAMINATION - Zn 11 GRAINS
TABLE: 8 MINERALOGY OF THE -100/+250 FRACTION (CONTINUED) SAMPLE HMC SAMPLE # FRACTION DESCRIPTION BLACK W/ WHITE COATINGS BROWN - TAN W/ THICK WHITE COATINGS WHITE TO SANDY BLACK W/ WHITE COATINGS BROWN TO TAN W/ ALMOST NO COATINGS WHITE BLACK W/ WHITE COATINGS BROWN W/ MINOR COATINGS WHITE
BLACK W/ WHITE COATINGS DK. BROWN W/ ALMOST NO COATINGS WHITE W/ SCATTERED BLACK BLACK W/ WHITE COATINGS DK. BROWN W/ MINOR COATINGS WHITE COMMENTS EUHEDRAL, BLACK W/ THICK COATINGS EUHEDRAL GREEN "PRISMS" RED FRAGMENTS EUHEDRAL GREEN "PRISMS" AND FRAGS BLACK, VITREOUS CLEAVAGE FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS PALE GREEN WAXY TO VITREOUS CUBE BLACK MICA MILKY TO CLEAR PLATES SILKY TO CLEAR HEXAGONAL PRISMS BROWN TO BLACK GRANULAR FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS RED FRAGMENTS YELLOW VITREOUS WEDGE MALLEABLE SILVER METALLIC SLIVER EUHEDRAL, BLACK W/ THICK COATINGS EUHEDRAL PALE GREEN "PRISMS" RED FRAGMENTS EUHEDRAL PALE GREEN "PRISMS" AND FRAGS BLACK, VITREOUS CLEAVAGE FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS PALE GREEN WAXY TO VITREOUS BLACK, THICK EUHEDRAL MICA BOOK SILKY TO CLEAR HEXAGONAL PRISMS MILKY TO CLEAR PLATES BROWN TO BLACK GRANULAR FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS YELLOW VITREOUS WEDGE EUHEDRAL, BLACK W/ THICK COATINGS EUHEDRAL PALE GREEN "PRISMS" RED FRAGMENTS EUHEDRAL PALE GREEN "PRISMS" AND FRAGS BLACK, VITREOUS CLEAVAGE FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS BROWN MICA MILKY TO CLEAR PLATES SILKY TO CLEAR HEXAGONAL PRISMS CLEAR AND PINK TETRAGONAL PRISMS YELLOW VITREOUS WEDGE BRASSY METALLIC CUBE EUHEDRAL, BLACK W/ COATINGS RED FRAGMENTS DK. GREEN TO BLACK CLEAVAGE FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS EUHEDRAL PALE GREEN "PRISMS" AND FRAGS BROWN TO BLACK GRANULAR FRAGMENTS MILKY TO CLEAR PLATES SILKY TO CLEAR HEXAGONAL PRISMS CLEAR AND PINK TETRAGONAL PRISMS YELLOW VITREOUS WEDGE EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS EUHEDRAL PALE GREEN "PRISMS" DK. GREEN TO BLACK CLEAVAGE FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS PALE GREEN WAXY TO VITREOUS BROWN MICA CUBE EUHEDRAL PALE GREEN "PRISMS" MILKY PLATES AND FRAGMENTS - COATS MILKY TO CLEAR PLATES SILKY TO CLEAR HEXAGONAL PRISMS CLEAR AND PINK TETRAGONAL PRISMS BROWN TO BLACK GRANULAR FRAGMENTS MALLEABLE SILVER METALLIC SLIVER BLACK MICA MINERAL IDENTIFICATION MAGNETITE PYROXENE - ENSTATITE FeOx PYROXENE - ENSTATITE AMPHIBOLE FeOx PUMPELLYITE FeOx/PYRITE BIOTITE BARITE APATITE APATITE - PHOSPHATE ZIRCON FeOx SPHENE CONTAMINATION - Zn MAGNETITE PYROXENE - ENSTATITE FeOx PYROXENE - ENSTATITE AMPHIBOLE FeOx PUMPELLYITE BIOTITE APATITE BARITE APATITE - PHOSPHATE ZIRCON SPHENE MAGNETITE PYROXENE - ENSTATITE FeOx PYROXENE - ENSTATITE AMPHIBOLE FeOx BIOTITE BARITE APATITE ZIRCON SPHENE PYRITE MAGNETITE FeOx AMPHIBOLE FeOx PYROXENE - ENSTATITE APATITE - PHOSPHATE BARITE APATITE ZIRCON SPHENE MAGNETITE FeOx PYROXENE - ENSTATITE AMPHIBOLE FeOx PUMPELLYITE BIOTITE FeOx/PYRITE PYROXENE - ENSTATITE BARITE BARITE APATITE ZIRCON APATITE - PHOSPHATE CONTAMINATION - Zn BIOTITE ESTIMATED ABUNDANCE 89Z 10Z 1Z S9Z 30Z 10Z 1Z RARE RARE 54Z 30Z 10Z SZ 1Z RARE 1 GRAIN 89Z 10Z 1Z S9Z 25Z 15Z 1Z RARE SOZ 30Z 10Z 10 Z RARE 89Z 10Z 1Z 40Z 40Z 20Z RARE 98Z 1Z 1Z RARE RARE 99Z 1Z 60Z 30Z 10Z SOZ 30Z 10Z 10Z RARE 99Z 1Z RARE 55Z 39Z 5Z 1Z RARE RARE RARE SOZ 30Z 10Z 5Z 5Z RARE
TABLE: 8 MINERALOGY OF THE -100/+250 FRACTION (CONTINUED) SAMPLE HMC SAMPLE # FRACTION DESCRIPTION BLACK W/ WHITE COATINGS BROWN W/ ALMOST NO COATINGS WHITE TO SANDY BLACK W/ WHITE COATINGS BROWN W/ ALMOST NO COATINGS SANDY BLACK W/ WHITE COATINGS BROWN W/ WHITE COATINGS
SANDY TO WHITE COMMENTS EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS DK. GREEN TO BLACK CLEAVAGE FRAGMENTS BROWN TO EUHEDRAL BLACK MICA MILKY TO CLEAR PLATES SILKY TO CLEAR HEXAGONAL PRISMS BROWN TO BLACK GRANULAR FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS RED FRAGMENTS MALLEABLE SILVER METALLIC SLIVER TARNISHED SULFIDE SOFT METALLIC MICACEOUS FLAKE ID BY XRD EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS DK. GREEN TO BLACK CLEAVAGE FRAGMENTS PALE YELLOW TO GREEN ID BY XRD YELLOW VITREOUS WEDGE MILKY TO CLEAR PLATES CLEAR AND PINK TETRAGONAL PRISMS BROWN TO BLACK GRANULAR FRAGMENTS SILKY TO CLEAR HEXAGONAL PRISMS RED FRAGMENTS BROWN MICA YELLOW VITREOUS WEDGE BRASSY METALLIC CUBE EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS MINERAL IDENTIFICATION MAGNETITE FeOx FeOx AMPHIBOLE BIOTITE BARITE APATITE APATITE - PHOSPHATE ZIRCON FeOx CONTAMINATION - Zn PYRITE MOLYBDENITE MAGNETITE FeOx FeOx AMPHIBOLE PUMPELLYITE SPHENE BARITE ZIRCON APATITE - PHOSPHATE APATITE FeOx BIOTITE SPHENE PYRITE MAGNETITE FeOx RED, BROWN, AND YELLOW FRAGMENTS W/ COATINGS FeOx EUHEDRAL, METALLIC PLATES DK. GREEN FIBROUS CLEAVAGE FRAGMENTS PALE YELLOW TO GREEN GOLD TO BROWN MICA CUBE PINK TETRAGONAL PRISM MILKY TO CLEAR PLATES BROWN TO BLACK GRANULAR FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS SILKY TO CLEAR HEXAGONAL PRISMS RED AND YELLOW FRAGMENTS BLACK MICA MALLEABLE SILVER METALLIC SLIVER SPEC. HEMATITE AMPHIBOLE PUMPELLYITE BIOTITE FeOx/PYRITE ZIRCON BARITE APATITE - PHOSPHATE ZIRCON APATITE FeOx BIOTITE CONTAMINATION - Zn ESTIMATED ABUNDANCE 99Z 1Z 10Z 1Z 40Z 30Z 15Z 10Z 5Z RARE RARE 1 GRAIN 99Z 1Z 65Z 20Z 10Z 5Z 60Z 20Z 10Z 10Z RARE RARE RARE RARE 99Z 1Z 64Z 30Z 5Z 1Z RARE RARE RARE 74Z 10Z 10Z 5Z 1Z RARE RARE INSUFFICIENT SAMPLE RUSTY BLACK W/ WHITE COATINGS TAN W/ ALMOST NO COATINGS WHITE W/ SCATTERED BLACK EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS PALE YELLOW TO GREEN EUHEDRAL, METALLIC PLATES MILKY TO CLEAR PLATES MILKY TO CLEAR PLATES ORANGE TO BLACK FRAGMENTS RED AND YELLOW FRAGMENTS STUBBY HEXAGONAL PRISMS CLEAR AND PINK TETRAGONAL PRISMS GOLD MICA MAGNETITE FeOx FeOx PUMPELLYITE SPEC. HEMATITE BARITE BARITE APATITE - PHOSPHATE FeOx APATITE ZIRCON BIOTITE 50Z 50Z 85Z 67Z 30Z 2Z 1Z RARE RARE
TABLE: 8 MINERALOGY OF THE -100/+250 FRACTION (CONTINUED) SAMPLE HMC SAMPLE # FRACTION DESCRIPTION BLACK W/ WHITE COATINGS BROWN W/ ALMOST NO COATINGS BLACK BLACK W/ WHITE COATINGS TAN W/ ALMOST NO COATINGS SANDY TO WHITE BLACK W/ WHITE COATINGS BROWN W/ ALMOST NO COATINGS SANDY
BLACK W/ WHITE COATINGS BROWN W/ NO COATINGS WHITE TO SANDY COMMENTS EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS EUHEDRAL, METALLIC PLATES PALE YELLOW TO GREEN BLACK EUHEDRAL MICA YELLOW VITREOUS WEDGE CUBE BROWN /BLACK BOTRYOIDAL GRAINS ID BY XRD SILKY TO CLEAR HEXAGONAL PRISMS SMALL MILKY PLATES CLEAR AND PINK TETRAGONAL PRISMS EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS PALE YELLOW TO GREEN EUHEDRAL, METALLIC PLATES BLACK MICA CUBE STUBBY HEXAGONAL PRISM MILKY TO CLEAR PLATES BLACK FRAGMENTS YELLOW TO ORANGE FRAGMENTS SILKY TO CLEAR HEXAGONAL PRISMS CLEAR AND PINK TETRAGONAL PRISMS CONTAMINATION - WHITE CHIPS SCARLET VITREOUS GRAINS ID BY XRD EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS EUHEDRAL, METALLIC PLATES PALE YELLOW TO GREEN RED MICA BLACK MICA PINK TETRAGONAL PRISM MILKY TO CLEAR PLATES YELLOW TO ORANGE FRAGMENTS SILKY TO CLEAR HEXAGONAL PRISMS CLEAR AND PINK TETRAGONAL PRISMS BLACK MICA BLACK FRAGMENTS EUHEDRAL, METALLIC PLATES YELLOW VITREOUS WEDGE EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS RED, BROWN, AND YELLOW FRAGMENTS PALE YELLOW TO GREEN EUHEDRAL, METALLIC PLATES BLACK EUHEDRAL MICA STUBBY HEXAGONAL PRISM NICE LARGE MILKY TO CLEAR PLATES SILKY TO CLEAR HEXAGONAL PRISMS YELLOW TO ORANGE FRAGMENTS BROWN TO BLACK FRAGMENTS PINK TETRAGONAL PRISM RED FRAGMENTS BADLY ETCHED TINY BRASSY CUBE MINERAL IDENTIFICATION MAGNETITE FeOx FeOx SPEC. HEMATITE PUMPELLYITE BIOTITE SPHENE FeOx/PYRITE APATITE - PHOSPHATE APATITE BARITE ZIRCON MAGNETITE FeOx FeOx PUMPELLYITE SPEC. HEMATITE BIOTITE FeOx/PYRITE APATITE BARITE APATITE - PHOSPHATE APATITE - PHOSPHATE APATITE ZIRCON PORCELAIN CHIPS CINNABAR MAGNETITE FeOx FeOx SPEC. HEMATITE PUMPELLYITE BIOTITE BIOTITE ZIRCON BARITE APATITE - PHOSPHATE APATITE ZIRCON BIOTITE APATITE - PHOSPHATE SPEC. HEMATITE SPHENE MAGNETITE FeOx FeOx PUMPELLYITE SPEC. HEMATITE BIOTITE APATITE BARITE APATITE APATITE - PHOSPHATE APATITE - PHOSPHATE ZIRCON FeOx PYRITE ESTIMATED ABUNDANCE 95Z 5Z 58Z 30Z 10Z 1Z 1Z RARE 50Z 25Z 15Z 10Z 99Z 1Z 80Z 10Z 10Z RARE RARE RARE 73Z 10Z 10Z 5Z 1Z 1Z 4 GRAINS 99Z 1Z A9Z 45Z 5Z 1Z RARE RARE 65Z 20 Z 10Z 5Z RARE RARE RARE RARE 90Z 10Z 85Z 10Z 5Z RARE RARE 69Z 20 Z 10Z 1Z RARE RARE RARE
TABLE: 8 MINERALOGY OF THE -100/+250 FRACTION (CONTINUED) SAMPLE HMC SAMPLE # FRACTION DESCRIPTION COMMENTS BLACK W/ WHITE COATINGS EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS BROWN W/ NO COATINGS RED, BROWN, AND YELLOW FRAGMENTS EUHEDRAL, METALLIC PLATES PALE YELLOW TO GREEN RED, WEATHERED MICA WHITE MICA STUBBY HEXAGONAL PRISM DK. GREEN FIBROUS CLEAVAGE FRAGMENTS PINK TETRAGONAL PRISM SANDY MILKY TO CLEAR PLATES CRUDDY PALE YELLOW TO ORANGE FRAGMENTS SILKY TO CLEAR HEXAGONAL PRISMS GRAY TO BLACK FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS BLACK EUHEDRAL MICA RED FRAGMENTS MALLEABLE SILVER METALLIC BALL BLACK W/ WHITE COATINGS EUHEDRAL, BLACK W/ COATINGS RED FRAGMENTS DK. BROWN W/ NO COATINGS RED, BROWN, AND YELLOW FRAGMENTS EUHEDRAL, METALLIC PLATES BLACK, SUBMETALLIC EUHEDRAL MICA MILKY TO CLEAR PLATES PINK TETRAGONAL PRISM PALE YELLOW TO GREEN CUBE YELLOW VITREOUS WEDGE WHITE MILKY TO CLEAR PLATES CLEAR AND PINK TETRAGONAL PRISMS RED FRAGMENTS SILKY TO CLEAR HEXAGONAL PRISMS EUHEDRAL, METALLIC PLATES BLACK W/ WHITE COATINGS EUHEDRAL, BLACK W/ THICK COATINGS RED FRAGMENTS BROWN W/ NO COATINGS EUHEDRAL, METALLIC PLATES RED, BROWN, AND YELLOW FRAGMENTS PALE YELLOW TO GREEN BLACK MICA PINK TETRAGONAL PRISM SANDY CRUDDY PALE YELLOW TO ORANGE FRAGMENTS SILKY TO CLEAR HEXAGONAL PRISMS MILKY TO CLEAR PLATES GRAY TO BLACK FRAGMENTS CLEAR AND PINK TETRAGONAL PRISMS BLACK EUHEDRAL MICA RED FRAGMENTS YELLOW VITREOUS WEDGE MINERAL IDENTIFICATION MAGNETITE FeOx FeOx SPEC. HEMATITE PUMPELLYITE BIOTITE MUSCOVITE APATITE AMPHIBOLE ZIRCON BARITE APATITE - PHOSPHATE APATITE APATITE - PHOSPHATE ZIRCON BIOTITE FeOx CONTAMINATION - Zn MAGNETITE FeOx FeOx SPEC. HEMATITE BIOTITE BARITE ZIRCON PUMPELLYITE FeOx/PYRITE SPHENE BARITE ZIRCON FeOx APATITE SPEC. HEMATITE MAGNETITE FeOx SPEC. HEMATITE FeOx PUMPELLYITE BIOTITE ZIRCON APATITE - PHOSPHATE APATITE BARITE APATITE - PHOSPHATE ZIRCON BIOTITE FeOx SPHENE ESTIMATED ABUNDANCE 97Z 3Z 79Z 15Z 5Z 1Z RARE RARE RARE RARE 59Z 20Z 15Z 5Z 1Z RARE RARE RARE 90Z 10Z 50Z 20 Z 20Z 10Z RARE RARE RARE RARE 90Z 5Z 5Z RARE RARE 100Z RARE 59Z 40Z 1Z RARE RARE 55Z 20Z 10Z 10Z 5Z RARE RARE RARE
TABLE: 9 MINERALOGY OF THE -20/+60 FRACTION HEAVY MINERAL CONCENTRATE SAMPLE HMC SAMPLE # FRACTION DESCRIPTION BLACK W/ WHITE COATINGS GRAY TO TAN W/ WHITE COATINGS WHITE AND BLACK GRAINS BLACK W/ WHITE COATINGS - 10 GRAINS GRAY TO TAN W/ WHITE COATINGS BLACK AND WHITE - ~30 GRAINS BLACK & RED W/ MINOR WHITE COATINGS COMMENTS EUHEDRAL W/ CLAY, CALCITE, BARITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW TO GREEN WAXY GRAINS CUBES AND PYRITOHEDRON BLACK GRAINS WITH WHITE COATINGS PLATES AND ROSETTES - AUTHIGENIC STUBBY PRISMS SINGLE TETRAGONAL PRISM SOME EUHEDRAL W/ CLAY, CALCITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW TO GREEN WAXY GRAINS PLATES - AUTHIGENIC CUBES AND PYRITOHEDRON TARNISHED SUBMETALLIC GRAIN - ID BY XRD GOLD WEATHERED MICA METAL SLIVER BLACK GRAINY VITREOUS FRAGMENTS PLATES - AUTHIGENIC RED FRAGMENTS EUHEDRAL TAN W/ WHITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW TO GREEN WAXY GRAINS - ID BY XRD CUBES BLACK W/ WHITE COATINGS A BLACK & RED W/ WHITE COATINGS GRAY TO TAN W/ WHITE COATINGS
WHITE BLACK TO DK. GREEN W/ WHITE COATINGS TAN W/ WHITE COATINGS BLACK AND WHITE BLACK & RED W/ MINOR WHITE COATINGS BLACK GRAINY VITREOUS FRAGMENTS PLATY - AUTHIGENIC RED, BROWN, YELLOW FRAGMENTAL GRAINS CONTAMINATION RED, BROWN, YELLOW FRAGMENTAL GRAINS EUHEDRAL, BLACK, METALLIC EUHEDRAL GREEN "PRISMS" W/ MAG. INCL. RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW TO GREEN WAXY GRAINS EUHEDRAL GREEN "PRISMS" ROSETTE - AUTHIGENIC CUBES AND PYRITOHEDRON PLATES & ROSETTES - AUTHIGENIC BLACK GRAINY VITREOUS FRAGMENTS EUHEDRAL GREEN "PRISMS" W/ MAG. INCL. EUHEDRAL WITH BARITE, CALCITE COATING RED, BROWN, YELLOW FRAGMENTAL GRAINS RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW TO GREEN WAXY GRAINS EUHEDRAL GREEN "PRISMS" - ID BY XRD CUBES BLACK CLEAVAGE FRAGMENT BLACK GRAINY VITREOUS FRAGMENTS PLATES - AUTHIGENIC RED, BROWN, YELLOW FRAGMENTAL GRAINS RED FRAGMENTS EUHEDRAL + RED OXIDIZED GRAINS CUBES AND PYRITOHEDRON EUHEDRAL GREEN "PRISMS" MINERAL IDENTIFICATION MAGNETITE FeOx PUMPELLYITE FeOx/PYRITE APATITE-PHOSPHATE BARITE APATITE ZIRCON MAGNETITE FeOx PUMPELLYITE BARITE FeOx/PYRITE FAYALITE BIOTITE ALUMINUM APATITE - PHOSPHATE BARITE MIXED FeOx MAGNETITE FeOx PUMPELLYITE FeOx/PYRITE APATITE - PHOSPHATE BARITE FeOx PORCELAIN CHIP FeOx MAGNETITE PYROXENE - ENSTATITE FeOx PUMPELLYITE PYROXENE - ENSTATITE BARITE FeOx/PYRITE BARITE APATITE - PHOSPHATE PYROXENE - ENSTATITE MAGNETITE MIXED FeOx FeOx PUMPELLYITE PYROXENE - ENSTATITE FeOx/PYRITE AMPHIBOLE APATITE - PHOSPHATE BARITE FeOx FeOx MAGNETITE FeOx/PYRITE PYROXENE - ENSTATITE ESTIMATED ABUNDANCE 100Z 90* 10Z RARE 80Z 20Z RARE RARE 100Z 89* 10Z 1Z RARE RARE RARE 1 GRAIN 80Z 20Z 90* 10Z 95Z SZ RARE 90* SZ SZ RARE 70Z 20Z 10Z SOZ SOZ RARE RARE RARE 100Z RARE 70Z 2SZ SZ 89* 10 Z 1Z RARE RARE 60Z 30Z 10Z 93Z SZ 1Z 1Z GRAY TO TAN W/ MINOR WHITE COATINGS WHITE RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW TO GREEN WAXY GRAINS CUBES AND PYRITOHEDRON EUHEDRAL GREEN "PRISMS" BLOCKY TRANSLUCENT MILKY GRAINS BLACK TO BROWN GRAINY VITREOUS FRAGMENTS PLATY - AUTHIGENIC CONTAMINATION FeOx 90* PUMPELLYITE 10Z FeOx/PYRITE RARE PYROXENE - ENSTATITE RARE BARITE 60Z APATITE - PHOSPHATE 30Z BARITE 10Z PORCELAIN CHIP 1 GRAIN
TABLE: 9 MINERALOGY OF THE -20/+60 FRACTION ... (CONTINUED) SAMPLE HMC SAMPLE MINERAL ESTIMATED # FRACTION DESCRIPTION COMMENTS IDENTIFICATION ABUNDANCE BLACK W/ WHITE COATINGS EUHEDRAL W/ CALCITE, BARITE COATING MAGNETITE 100Z METALLIC SLIVER - CONTAMINATION STEEL RARE TAN W/ WHITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS FeOx 90Z YELLOW TO GREEN WAXY GRAINS PUMPELLYITE 10Z CUBE FeOx/PYRITE RARE EUHEDRAL GREEN "PRISMS" EPIDOTE RARE BLACK BLACK GRAINY VITREOUS FRAGMENTS APATITE - PHOSPHATE 90Z PLATES - AUTHIGENIC BARITE 10Z BLACK W/ WHITE COATINGS EUHEDRAL W/ CALCITE, BARITE COATING MAGNETITE 100Z EUHEDRAL GREEN "PRISMS" W/ MAG. INCL. PYROXENE - ENSTATITE RARE GRAY TO TAN W/ WHITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS FeOx 90Z YELLOW TO GREEN WAXY GRAINS PUMPELLYITE 10Z EUHEDRAL GREEN "PRISMS" PYROXENE - ENSTATITE RARE CUBES FeOx/PYRITE RARE PLATES - AUTHIGENIC BARITE RARE WHITE PLATES & ROSETTES - AUTHIGENIC BARITE 70Z GRAY TO BLACK GRAINY VITREOUS FRAGMENTS APATITE - PHOSPHATE 30Z RED, BROWN, YELLOW FRAGMENTAL GRAINS FeOz 1 GRAIN TAN W/ MINOR WHITE COATINGS RED FRAGMENTAL GRAINS MIXED FeOx 80Z EUHEDRAL, BLACK MAGNETITE 20Z EUHEDRAL GREEN "PRISMS" PYROXENE - ENSTATITE RARE TAN W/ MINOR WHITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS FeOx 95Z YELLOW TO GREEN WAXY GRAINS PUMPELLYITE 5Z EUHEDRAL GREEN "PRISMS" PYROXENE - ENSTATITE RARE CUBES FeOx/PYRITE RARE BLACK W/ GRAY WHITE TO TAN BLACK COATINGS W/ WHITE BLACK GRAINY VITREOUS FRAGMENTS WAXY PLATE - 26 GRAINS COATINGS EUHEDRAL W/ MATRIX COATING RED, BROWN, YELLOW FRAGMENTAL GRAINS APATITE - PHOSPHATE 100Z BARITE RARE MAGNETITE FeOx 100Z 95Z YELLOW TO GREEN WAXY GRAINS PUMPELLYITE 5Z CUBES FeOx/PYRITE RARE GRAY GRAY TO BLACK GRAINY VITREOUS FRAGMENTS PLATES - AUTHIGENIC RED FRAGMENTAL GRAINS GOLD MICA BLACK W/ MINOR WHITE COATINGS EUHEDRAL W/ BARITE, CALCITE COATING RED FRAGMENTAL GRAINS APATITE - PHOSPHATE BARITE FeOx WEATHERED BIOTITE MAGNETITE MIXED FeOx 80Z 10Z 10Z RARE 100Z RARE TAN W/ WHITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS FeOx 85Z YELLOW TO GREEN WAXY GRAINS PUMPELLYITE 15Z CUBES AND PYRITOHEDRON FeOx/PYRITE RARE YELLOW - ORANGE VITREOUS SPHENE RARE BLACK BOTRYIODAL OXIDE MnOx or HEMATITE RARE STUBBY HEXAQONAL PRISM APATITE RARE GRAY BLACK GRAINY VITREOUS FRAGMENTS APATITE - PHOSPHATE 85Z PLATES - AUTHIGENIC BARITE 10Z RED, BROWN, YELLOW FRAGMENTAL GRAINS FeOx 5Z BLACK W/ WHITE COATINGS EUHEDRAL BLACK W/ BARITE, CALCITE COATINGS MAGNETITE 60Z RED FRAGMENTAL GRAINS MIXED FeOx 40Z TAN W/ WHITE COATINGS RED, BROWN, YELLOW GRAINS - THICK COATINGS FeOx 100Z YELLOW TO GREEN WAXY GRAINS PUMPELLYITE RARE WHITE MICACEOUS FRAGMENT SERICITE RARE PLATE - AUTHIGENIC BARITE RARE BLACK AND WHITE - 25 GRAINS BLACK GRAINY VITREOUS FRAGMENTS APATITE - PHOSPHATE 50Z BLACK AND RED FRAGMENTAL GRAINS FeOx + MnOx 25Z PLATES & ROSETTES - AUTHIGENIC BARITE 25Z CONTAMINATION PORCELAIN CHIP RARE
TABLE: 9 MINERALOGY OF THE -20/+60 FRACTION ... (CONTINUED) SAMPLE HMC # FRACTION SAMPLE DESCRIPTION COMMENTS MINERAL IDENTIFICATION ESTIMATED ABUNDANCE GRAY TO WHITE W/ THICK COATINGS TAN W/ MINOR COATINGS BLACK MIXED GRAINS W/ CALCITE, BARITE, SERICITE COATS EUHEDRAL GRAINS W/ WHITE COATINGS RED, BROWN, YELLOW FRAGMENTAL GRAINS DK. GREEN TO YELLOW VITREOUS/WAXY ID BY XRD CUBES AND PYRITOHEDRON BLACK VITREOUS - SUBMETALLIC BOTRYOIDAL FeOx 70Z MAGNETITE 30Z FeOx 95Z PUMPELLYITE 5Z FeOx/PYRITE RARE MnOx RARE BLACK GRAINY VITREOUS FRAGMENTS PLATES - AUTHIGENIC LT. YELLOW TRANSLUCENT GRAINS (1 DIMPLED) APATITE - PHOSPHATE 95Z BARITE 5Z PHOSPHATE FOSSIL RARE TAN W/ V. MINOR WHITE COATINGS TAN W/ ALMOST NO COATINGS WHITE AND BLACK RED FRAGMENTAL GRAINS EUHEDRAL, BLACK METALLIC PLATES & ROSETTES - AUTHIGENIC METALLIC CONTAMINATION RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW GREEN WAXY GRAINS CUBES PLATES - AUTHIGENIC PLATES & ROSETTES - AUTHIGENIC BLACK GRAINY VITREOUS FRAGMENTS LT. BROWN-OFF WHITE TRANSLUCENT RED GRAINS MIXED FeOx 80Z MAGNETITE 20Z BARITE RARE STEEL SLIVER RARE FeOx 9SZ PUMPELLYITE 5Z FeOx/PYRITE RARE BARITE RARE BARITE 60Z APATITE - PHOSPHATE 30Z APATITE 10Z FeOx RARE BLACK W/ MINOR WHITE COATINGS TAN W/ ALMOST NO COATINGS EUHEDRAL, BLACK METALLIC RED, BROWN FRAGMENTAL GRAINS PLATES - AUTHIGENIC W/ MAG. INCL. RED, BROWN, YELLOW FRAGMENTAL GRAINS RED MICA YELLOW GREEN WAXY GRAINS BLACK BOTRYOIDAL VITREOUS GRAINS EUHEDRAL BLACK MICA CUBES MAGNETITE 79Z FeOx 20Z BARITE 1Z FeOx 90Z WEATHERED BIOTITE 5Z PUMPELLYITE 5Z MnOx RARE BIOTITE RARE FeOx/PYRITE RARE BLACK BLACK & TAN W/ WHITE COATINGS TAN W/ ALMOST NO COATINGS BLACK GRAINY VITREOUS FRAGMENTS BLACK BOTRYOIDAL VITREOUS GRAINS PLATES - AUTHIGENIC STUBBY HEXAGONAL PRISMATIC GRAINS RED FRAGMENTAL GRAINS EUHEDRAL, BLACK W/ SOME THICK COATS RED, BROWN, YELLOW FRAGMENTAL GRAINS RED, BROWN, YELLOW FRAGMENTAL GRAINS APATITE - PHOSPHATE MnOx BARITE APATITE FeOx MAGNETITE FeOx FeOx 74Z 20Z 5Z 1Z RARE 60Z 40Z 97Z GRAY TO TAN YELLOW GREEN WAXY GRAINS CLUSTER OF PLATES W/ MATRIX CUBES AND PYRITOHEDRONS BLACK GRAINY VITREOUS FRAGMENTS RED MICA BOOKS BLACK GRAINY VITREOUS FRAGMENTS GRAY TO BROWN TRANSLUCENT BLACK BOTRYIODAL PLATES - AUTHIGENIC PUMPELLYITE 3Z BARITE RARE FeOx/PYRITE RARE APATITE - PHOSPHATE RARE WEATHERED BIOTITE RARE APATITE - PHOSPHATE 40Z PHOSPHATES 40Z MnOx 10Z BARITE 10Z BLACK W/ WHITE COATINGS TAN W/ WHITE COATINGS WHITE - ABOUT 25 GRAINS EUHEDRAL, SOME W/ THICK CALCITE, BARITE COATS RED GRAINS - OXIDIZED MAGNETITE RED, BROWN, YELLOW FRAGMENTAL GRAINS RED, BROWN MICA BLACK MICA CUBE MAGNETITE FeOx FeOx WEATHERED BIOTITE BIOTITE FeOx/PYRITE PLATES - AUTHIGENIC STUBBY HEXAGONAL PRISMATIC GRAINS WAXY GRAY TO BROWN BLACK GRAINY VITREOUS FRAGMENTS BARITE APATITE PHOSPHATE APATITE - PHOSPHATE 90Z 10Z 90Z 10Z RARE RARE 50Z 25Z 20Z 5Z
TABLE: 9 MINERALOGY OF THE -20/+60 FRACTION ... (CONTINUED) SAMPLE HMC # FRACTION SAMPLE DESCRIPTION COMMENTS MINERAL IDENTIFICATION ESTIMATED ABUNDANCE BLACK - RED W/ MINOR WHITE COATINGS TAN W/ ALMOST NO COATINGS WHITE EUHEDRAL, BLACK METALLIC RED FRAGMENTAL GRAINS GOLD COLORED MICA SPLENDENT ETCHED METALLIC PLATE METALLIC CONTAMINATION RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW GREEN WAXY GRAINS CUBES AND PYRITOHEDRONS GOLD WEATHERED MICA PLATES - AUTHIGENIC BLACK GRAINY VITREOUS FRAGMENTS CLEAR - OFF WHITE STUBBY PRISMS MAGNETITE 70Z FeOx 30Z BIOTITE RARE SPEC. HEMATITE RARE STEEL SLIVER RARE FeOx 99Z PUMPELLYITE 1Z FeOx/PYRITE RARE BIOTITE RARE BARITE 70Z APATITE - PHOSPHATE 20Z APATITE 10Z BLACK W/ WHITE COATINGS TAN W/ ALMOST NO COATINGS GRAY - YELLOW EUHEDRAL, BLACK METALLIC - 30 GRAINS RED GRAINS PLATES - AUTHIGENIC W/ MAG. INCL. RED, BROWN, YELLOW FRAGMENTAL GRAINS YELLOW GREEN WAXY GRAINS CUBE RED MICA BOOK WHITE MICA MAGNETITE FeOx BARITE FeOx PUMPELLYITE FeOx/PYRITE BIOTITE MUSCOVITE GRAY TO BLACK GRAINY VITREOUS FRAGMENTS APATITE - PHOSPHATE YELLOW-ORANGE TRANSLUCENT WAXY - ID BY XRD APATITE PLATES - AUTHIGENIC BARITE STUBBY HEXAGONAL PRISMATIC GRAINS APATITE 85Z 10Z 5Z 99Z 1Z RARE RARE RARE 50Z 40Z 5Z 5Z RED W/ WHITE COATINGS TAN W/ WHITE COATINGS RED GRAINS EUHEDRAL, BLACK METALLIC CUBES RED, BROWN, YELLOW FRAGMENTAL GRAINS PLATES - AUTHIGENIC EUHEDRAL BLACK MICA - 1 GRAIN CUBES AND PYRITOHEDRONS WHITE MICA - 1 GRAIN FeOx MAGNETITE FeOx/PYRITE FeOx BARITE BIOTITE FeOx/PYRITE MUSCOVITE 90Z 8Z 2Z 9SZ 5Z RARE RARE RARE WHITE - 10 GRAINS BLACK W/ WHITE COATINGS
TAN W/ MINOR WHITE COATINGS PLATES - AUTHIGENIC RED GRAINS EUHEDRAL SOME W/ THICK BARITE, CALCITE COATS RED FRAGMENTAL GRAINS RED, BROWN, YELLOW FRAGMENTAL GRAINS BARITE FeOx MAGNETITE FeOx FeOx 80Z 20Z 99Z 1Z 9SZ DARK GRAY - 35 GRAINS BLACK BOTRYOIDAL GRAINS YELLOW GREEN WAXY GRAINS CUBE BLACK EUHEDRAL MICA DARK GRAY MICROCRYSTALLINE FRAGMENTS STUBBY HEXAGONAL PRISMATIC GRAINS CONTAMINATION MnOx PUMPELLYITE RARE FeOx/PYRITE RARE BIOTITE RARE APATITE - PHOSPHATE 90Z APATITE 10Z PORCELAIN CHIP RARE
MINERALOGY OF HEAVY-MINERAL CONCENTRATES Minerals in each magnetic split of the heavy-mineral concentrates were Identified by examination with a binocular microscope. X-ray diffraction (XRD) was used to confirm identifications. Each sample was also examined under short-wave ultraviolet (UV) light for the presence of scheelite [CaW04 ] and other fluorescing minerals. No scheelite or powellite (Ca(Mo,W)04 J was observed in any of the samples. The percent abundance for each mineral present in each fraction was estimated. Tables 8 and 9 list the description, identification, and estimated abundance for each mineral. Several abbreviations are used in the tables and their intended meanings are as follows: -Strongly magnetic split of the heavy-mineral concentrate -weakly magnetic split of the heavy-mineral concentrate -"Non-magnetic" split of the heavy-mineral concentrate DK. -Dark FeOx -Undifferentiated secondary iron oxide minerals FeOx/PYRITE -Iron oxide pseudomorph after pyrite HMC -Heavy-mineral concentrate ID BY XRD -Identification confirmed by X-ray Diffraction INCL. -Inclusion(s) LT. -Light MAG. -Magnetite MnOx -Undifferentiated manganese oxides SPEC. HEMATITE -Specularite, variety of hematite -Very W/ -With X-ray Diffraction Analysis X-ray diffraction analyses were made of various size fractions prepared by Steven Smith (U.S.G.S) to determine major minerals and variations in mineralogy with grain size and with depth of sample. Size fractions used were -20/+60 mesh, -60/+100 mesh, -100/+250 mesh, and -250 mesh. A small split of each size fraction was prepared as a smear on glass; XRD patterns were run with copper radiation at goniometer speed of 2° 20 per minute, and chart speed of 2° per minute. Peak heights were measured (in arbitrary units) above background at 9° 20 (mica), 12.5° (kaolinite) 20.9° quartz, 28° feldspar, and 43.2° calcite. The area of the peak at 6° was used as measure of the amount of montmorillonite. Peaks were selected to be as free from interference as possible and to be on scale for all samples. The measurements show in a semiquantitative manner the change in amounts of various minerals with depth. Small differences in peak heights for the same mineral in different samples are not significant; large differences indicate differences in the amount of the mineral present in the samples. No attempt was made to determine the amount of the various minerals present in the samples. Quartz, feldspar, and calcite are the dominate mineral. Variations in the amount of quartz and feldspar are probably due to variations in sedimentation and erosion in the formation of the alluvium. Calcite is present in part as caliche and in part as limestone pebbles. Clay minerals are present in no more than small amounts in most samples.
Table 10. Peak heights from XRD patterns of -20/+60 mesh material from Rabbit Creek drill hole, Hunboldt County, Nevada [Degrees 20 are approximate location of XRD peak used; Mont, montmorillonite, group minerals, area of peak in arbitrary units; mica, mica of various types; K, kaolinite group minerals; Q, quartz; F, feldspar group minerals; calcite, calcite peak at 43.2° 20 selected since it did not go off scale in any of these patterns; , no peak measureable] Sample No. Mont 6°
Mica K 9° 12.5°
Q 21° F Calcite 28° 43.2°
Table 11. Peak heights from XRD patterns of -60/+100 mesh material from Rabbit Creek drill hole, Humboldt County, Nevada [Degrees 20 are approximate location of XRD peak used; Mont, montmorillonite, group minerals, area of peak in arbitrary units; mica, mica of various types; K, kaolinite group min- erals; Q, quartz; F, feldspar group minerals; calcite, calcite peak at 43.2° 20 selected since it did not go off scale in any of these patterns; , no peak measureable] Sample No. Mont 6°
Mica 9° (1) K 12.5°
Q 21° F Calcite 28° 43.2°
Table 12.--Peak heights from XRD patterns of -100/+250 mesh material from Rabbit Creek drill hole, Hunboldt County, Nevada [Degrees 29 are approximate location of XRD peak used; Mont, montmorillonite, group minerals, area of peak in arbitrary units; mica, mica of various types; K, kaolinite group minerals; Q, quartz; F, feldspar group minerals; calcite, calcite peak at 43.2° 20 selected since it did not go off scale in any of these patterns; --, no peak measureable] Sample Mont No. 6° No sample Mica 9° K 12.5°
Q 21° F Calcite 28° 43.2°
Table 13. Peak heights froo XRO patterns of -250 mesh material fron Rabbit Creek drill hole, Hunboldt County, Nevada [Degrees 20 are approximate location of XRD peak used; Mont, montmornionlte, group minerals, area of peak in arbitrary units; mica, mica of various types; K, kaolinite group minerals; Q, quartz; F, feldspar group minerals; calcite, calcite peak at 43.2° 20 selected since it did not go off scale in any of these patterns; , no peak measureable] Sample No. Mont 6° Mica go Quartz 20.8° Feldspar 28° Calcite 43.2°
SEQUENTIAL EXTRACTIONS OF THE -250 MESH FRACTION FOR THE DETERMINATION OF 18 ELEMENTS The sequential extraction scheme used on the minus-250-mesh fraction of selected Rabbit Creek core samples was modeled after procedures described by Chao (1984). This scheme was designed to solubilize and separate chemical phases of the alluvial material in the following order: (1) carbonates and exchangeable metals; (2) Mn oxides and amorphous Fe oxides; (3) crystalline Fe oxides; (4) sulfides; and (5) the residue ("silicate fraction"). Extraction Method and Analysis 1. Carbonate and exchangeable metals: In a polypropylene centrifuge tube, 25 ml of 1 M acetic acid was added to a 1 g split of minus 250 mesh sample. The capped tubes were agitated on a horizontal shaker for 2 hours. The samples were then centrifuged and decanted with the leachate saved for analysis. 2. Mn oxides and amorphous Fe oxides: Twenty-five milliliters of 0.25 M hydroxylamine hydrochloride in 0.25 M hydrochloric acid was added to the residual material from extraction 1. The tubes were placed in a water bath at 50°C for 30 minutes. The samples were then centrifuged and decanted with the leachate saved for analysis. 3. Crystalline Fe oxides: Twenty-five milliliters of 4 N hydrochloric acid was added to the residual material from extraction 2. The tubes were placed in a water bath at 95°C for 30 minutes. The samples were then centrifuged and decanted with the leachate saved for analysis. 4. Sulfides: Two grams of potassium chlorate and 10 ml of concentrated hydrochloric acid was added to the residual material from extraction 3. The samples were left to stand at room temperature for 45 minutes. The samples were diluted with 15 ml of water, centrifuged, and decanted with the leachate saved for analysis. 5. Residue ("silicate fraction"): Ten mi 11ilHers of concentrated nitric acid was added to 50 ml teflon beakers containing the residual material from extraction 4 and the resultant solutions were heated on a hot plate at 110°C for 10 minutes. Ten mi Hi liters of perchloric acid and 10 ml of 48 percent hydrofluoric acid were added and the samples placed on a hot plate at 220°C until a moist bead was obtained. Twenty-five milliliters of 4 N hydrochloric acid was added and the samples heated at 100°C for 30 minutes. The solutions were transferred to centrifuge tubes, centrifuged, and decanted with the liquid saved for analysis. A separate total digestion was performed on each sample with a fresh 1 g split using the same procedure as in "5". Each solution was analyzed for 18 elements using induction coupled plasma-atomic emission spectrometry (tables 14 and 15).
Table 14. Lower Units of determination for elements analyzed for by ICP-AES after extraction Element Lower Limit of Determination percent Iron (Fe) Calcium (Ca) Aluminum (Al) parts per million Arsenic (As) Barium (Ba) Cobalt (Co) Chromium (Cr) Copper (Cu) Lead (Pb) Manganese (Mn) Nickel (Ni) Phosphorus (P) Sodium (Na) Strontium (Sr) Titanium (Ti) Tungsten (W) Zinc (Zn) Zirconium (Zr)
Table 15. Determination of 18 elements after sequential extraction of -250 mesh fraction of Rabbit Creek drill core. Inductively Coupled Plasma Emission Spectrographic Analyses of Extracted "Fractions" and Total Digestions ("0" not detected at lower limit of determination) CO Sample Element Number FeW Ca(*) AH*) 14 As(ppm) Carbonate Exchangeable Metals Mn-Oxides Amorph. Fe-Oxides Crystalline Fe-Oxides Su If ides Residue Total Digestion
CO vo Table 15. continued Sample Element Number 14 Ba(ppm) 14 Co(ppm)
14 Cr(ppm) 14 Cu(ppm) Carbonate Exchangeable Metals Mn-Oxides Amorph. Fe-Oxides Crystalline Fe-Oxides Sul fides Residue Total Digestion
Table 15. continued ile Element >er 14 Pb(ppm) 14 Mn(ppm) 14 Ni(ppm) P(ppm) Carbonate Exchangeable Metals Mn-Oxides Amorph. Fe-Oxides Crystalline Fe-Oxides Su If ides Residue Total Digestion
Table 15. continued Sample Element Number 14 Na(ppm) 14 Sr(ppm) 14 Ti(ppm) W(ppm) Carbonate Exchangeable Metals Mn-Oxides Amorph. Fe-Oxides Crystalline Fe-Oxides Su If ides Residue Total Digestion
Table 15. continued Sample Element Number 14 Zn(ppm) 14 Zr(ppm) Carbonate Exchangeable Metals Mn-Oxides Amorph. Fe Fe-Oxides Crystalline Fe-Oxides Sulfides Residue Total Digestion
Cold vapor-atomic absorption spectrophotonetry (CV-AAS) for the analysis of mercury The minus 100/+250 mesh fraction and the pulverized minus 20/+60 mesh fraction were analyzed for mercury by a continuous flow-cold vapor-atomic absorption spectrophotometric method (Kennedy and Crock, 1987). To determine mercury in geologic materials, samples are digested with nitric acid and sodium dichromate in a closed Teflon vessel. After bringing to a constant weight, the digest is mixed with air and a sodium chloride-hydroxylamine hydrochloride-sulfuric acid solution and then Hg (II) is reduced to Hg° with stannous chloride in a continuous flow manifold. The mercury vapor is separated and measured using cold vapor atomic absorption spectrophotometry (CV-AAS). Table 16. Analytical results for mercury shown in ppn Sample number Size -100/+250 mesh fraction -20/+60 mesh (pulverized) Visible-absorption-spectrophotoaetry for the analysis of tungsten The minus 100/+250 mesh fraction and the pulverized minus 20/+60 mesh fraction were analyzed for tungsten by visible absorption spectrophotometry (Welsch, 1983). The sample is decomposed by nitric and hydrofluoric acids and the residue is dissolved in 80# hydrochloric acid. A clear aliquot of the solution is treated with stannous chloride to inhibit interferences, particularly from molybdenum. The blue tungsten dithiol complex is developed
at 95 °C within a half-hour period. The complex is extracted into 4 ml heptane and the concentration is determined by measuring the absorption at 630 nm with a visible wavelength-range absorption spectrophotometer. Table 17. Analytical results for tungsten shown in ppn Size fraction Sample number -100/+250 mesh -20/+60 mesh (pulverized) Ion specific electrode (ISE) analysis for fluorlde The minus 100/+250 mesh fraction and the pulvarized minus 20/+60 mesh fraction were analyzed for fluoride by a ion-specific electrode (ISE) method (Hopkins, 1977; O'Leary and Meier, 1986). Samples are fused with a sodium carbonate-potassium carbonate-potassium nitrate flux and the fused sample is dissolved with citric acid. Sodium citrathe buffer, which also serves as an ionic strength adjuster, is then added to this solution prior to determining the fluorine concentration by standard-addition technique using ISE.
Table 18. Analytical results for fluoride shown in ppn Size fraction Sample number -100/+250 mesh -20/+60 mesh (pulverized) Method: Flame atonic-absorption spectroscopy (FAA) for the determination of Sb, As, B1 Cd, and Zn The minus 100/+250 mesh fraction and the pulverized minus 20/+60 mesh fraction were analyzed for antimony, arsenic, bismush, cadmium, and zinc by flame atomic absorption spectroscopy (O'Leary and Viets, 1986). A chlorine- liberating solution of hychochloric acid and hydrogen peroxide is used to solubilize most nonsilicate bound metals found in geologic materials. The five metals of interest are selectively extracted into a 10 percent aliquat 336-MIBK organic phase in the presence of ascorbic acid and potassium iodide in 6 N HC1. The metals are then determined by flame atomic absorption spectroscopy (O'Leary and Viets, 1986).
Table 19. Analytical results for antloony, arsenic, bismuth, cadniui zinc, shown 1n ppo. and Size fraction -100/+250 mesh Sample number Sb As Bi M(D N(l) N(D M(l) N(l) N(l) N(D N(D N(l) N(l) N(D N(D N(l) N ( 1 ) v / N(l) N(D N(D N(D Cd Zn -20/+60 mesh (pulverized) Sb As Bi N(D N ( 1 ) / N (1 ) N(l) M(l) N(l) N ( 1 ) N(l) N(l) N(l) N(l) N(D N(l) N ( 1) Cd Zn
Arsenic Species Analysis A moderately strong acid solution (4.0 N HC1) extracts arsenic from solid samples. The arsenic that is extracted is associated with amorphous and crystalline iron and manganese oxyhydroxides (Chao and Zhou, 1983). The extracted arsenic may occur in two oxidation states which are not altered by the acid extraction. The concentration of arsenic in each oxidation state can be determined using the ion exchange technique for water developed by Pick!in (1983) and adapted to solid phase extractions by Pick!in and Callender (1987). Cherry and others (1979) suggest that dissolved arsenic assumes the proper ratio of As(III) (arsenite) to As(V) (arsenate) to reflect the oxidation-reduction potential of a given ground water system. Pick!in and Callender (1987) observed that solid phase arsenic species were an indication of redox conditions in lacustrine sediments. In oxidized sediments they found exclusively As(V) while in reduced sediments they found both As(III) and As(V). The results for extraction and speciation of arsenic in the Rabbit Creek core samples are listed in table 20. Almost all of the extracted arsenic in the samples occurred as As(V) with only minor occurrences of As(III). A bar graph of the arsenic concentrations vs depth for the -250 fraction is presented in figure 1. Results in table 20 marked with a star are concentrations determined from samples that appeared to be different material than the other samples in this set. (Some of the arsenic may have oxidized during sample preparation) Some clasts were separated from the bulk material of the core samples. After preparation, arsenic was extracted and speciated as described above. Results are listed in table 21. The arsenic in the clasts also occurred mainly as As(V) with only some minor occurrences of As(III).
Table 20. Analytical results for extractable As species in seived Rabbit Creek core samples [AsIII was run on the -100/+250 fraction and it was not detected in any of the samples, therefore it does not appear in the table] Sample As III rag/kg As V mg/kg -100/+250 As V mg/kg no data -20/+60 As III mg/kg 209* 1432* -20/+60 As V mg/kg 1700* 2870* 5334* Table 21. Analytical results for extractable As species in selected clasts fro Rabbit Creek core saaples Sample Id 4a 16d 18a 18d 19b Lithology gossan angular siltstone gossan gossan hard siltstone partly silicified or metamorphic foliation silicified and/or chert iron stained orange siltstone dark gray silicified silicified, maybe quartz vein AsIII(mg/kg)
As(V) mg/kg
Gold Analysis Three sieve fractions of the prepared drill core were analyzed for gold. The three fractions were the ground -20/+60 mesh split, -1007+250 split, and -250 split. In addition, 43 ground clast samples collected from the +4 mesh fraction were analyzed for gold. A 10-gram sample is roasted for 1 hour at 700 °C, gold is then extracted with hydrobromic acid - 0.5 percent bromine solution and MIBK (methyl isobutyl ketone). An electrothermal atomic absorption spectrometer with background corrector was used to determine gold to 1 ppb detection limit (O'Leary and Meier, 1986). Table 22 shows the gold values for the samples in ppb. In some of the clast samples there was not enough sample to give a 1 ppb detection limit, therefore, resulting in a higher detection limit for these samples. Table 22. Gold in alluvium from sieved core from Rabbit Creek drill hole (N, not detected; <,detected but below the limit of determination shown; , no data; values reported in parts per billion (ppb)] Sample -20/+60 -100/+250
Table 23. Gold in selected clasts from core from Rabbit Creek drill hole [N, not detected; detected but below the limit of determination shown; , no data; values reported in parts per billion (ppb)] Au, ppb Au, ppb Au, ppb IB
11B
15D Id
12A
15E 3B 16A 13A
4D 13B
16D 4Ee 17A 14A 17Aa
7B 14B ISA 8B 18B 9B 15A 15B 18D 19A 19B 19BB 19C 21A 21B 21D Au, ppb
Gas chronatography Cored alluvium samples were analyzed by methods used by Hinkle and Gilbert (1984), Hinkle and Botinelly, (1988), and Hinkle (1986, 1988): grams of -20/+60 mesh sample were placed in 10 ml size evacuated blood sampling vials. The vials were stoppered with air-tight rubber stoppers, and placed in an incubator at 47 °C. Two sets of samples were placed in the incubator and heated for different times, one set was heated for 20-26 hours, and the other set was heated for 5 days. Headspace gas in the vials was removed by injecting 5 ml of air and withdrawing 5 ml of mixed air and headspace gas. The gas samples were analyzed for C02 , 02 , S02 , and CS2 by gas chromatography, using two gas chromatographs with connected sample loops; operating conditions for the gas chromatographs are shown in table 24. Concentrations of volatiles of interest in the headspace gases were calculated by comparison to standard curves; concentrations of these volatiles in the added atmospheric air were subtracted from the values determined. Results of the two sets of analyses were very close and the averages are shown in table 25; results for COo are reported in percent (volume/volume), results for S02 and CSo are reported as relative peak areas because the concentrations were near the Tower limit of determination. Results for 02 are not reported because all samples were determined to be the same composition of atmospheric air.
Table 24. Gas chronatograph operating conditions Chromatograph 1 Chromatograph 2 Gases analyzed C02 , 02 Detector thermistor detector Lower limit of detection Column Carrier gas Temperature 0.03* C02, (vol/vol) concentric stainless steel outer column: 72 in x 1/4 in molecular sieve. Inner column 72 in x 1/8 in Porapak mixture (Alltech Assoc. Deerfield, 111.) helium at 90 mL/min column: 70 °C detector: low mode H2S, COS, CS2 , S02 , CH3SH Hall electrolytic conductivity detector, operated in the sulfur mode 500 ppb of any sulfur compound (vol/vol) 30 in x 1/8 in Teflon packed with 18 in of acetone-washed 80/100 mesh Porapak QS (Supelpak-S) (Supelco, Inc., Bellefonte, Pa.) ultra-high purity He at 60 mL/min Hall detector: Methanol flow rate 0.5 mL/min. Ultra high air flow rate= 35 mL/min. both columns in same oven: 50 °C, programmed to 150 °C for 7 min.
Table 25. Analysis of core samples for C02, 02 , S02 , and C$2 reported In % was found to be the same as atmospheric air in all samples and has not been included in the table] Sample S02 ppb C$2 ppb co2
Total atonic emission spectrography for the determination of 35 elements Three of the seived fractions and the whole clasts were analyzed by de-arc emission spectrography (Grimes and Marranzino, 1968). Ten milligrams (mg) of prepared sample is mixed with 20 mg of spectrographically pure powdered graphite and placed in a performed 6.35-mm-diameter cupped electroded where it is packed and vented. The electrode containing the sample is placed opposite a counter electrode in the arc stand where it is arced at 13 ampere for 2.25 min. The resulting spectra from the volatization of the sample is recorded on film. The developed film is then visually compared to a standard film and element concentrations are determined. Concentrations are reported as the approximate midpoints of geometric brackets whose boundaries are 0.825, 1.211, 1.77, 2.61, 3.83, 5.62, 8.52, or any order of magnitude therein of the dynamic working range of a particular element. The 35 elements analyzed for and the upper and lower limits of determination used are presented in table 26. The results from the analysis of the three sieve fraction (-20/+60, -100/+250, and -250) and whole clasts are presented in tables 27-30. Of the 35 elements reported Au, Bi, Cd, Sn, and Th do not appear in the table 27- 30. These elements were looked for but were not detected at their respective lower limits of determination in any of the samples.
Table 26. Units of determination for the spectrographic analysis of geologic materials based on a 10-rog sample [The spectrographic limits of determination for heavy-mineral-concentrate samples and oxalic acid leachates are based on a 5-mg sample, and are therefore two reporting intervals higher than the limits given for rocks and stream sediments] Elements Lower determination limit Upper determination limit Percent Iron (Fe) Magnesium (Mg) Calcium (Ca) Titanium (Ti) Parts per million Manganese (Mn) Silver (Ag) Arsenic (As) Gold (Au) Boron (B) Barium (Ba) Beryllium (Be) Bismuth (Bi) Cadmium (Cd) Cobalt (Co) Chromium (Cr) Copper (Cu) Lanthanum (La) Molybdenum (Mo) Niobium (Nb) Nickel (Ni) Lead (Pb) Antimony (Sb) Scandium (Sc) Tin (Sn) Strontium (Sr) Vanadium (V) Tungsten (W) Yttrium (Y) Zinc (Zn) Zirconium (Zr) Thorium (Th) 5,000 5,000 10,000 2,000 5,000 1,000 1,000 2,000 5,000 20,000 1,000 2,000 2,000 5,000 20,000 10,000 1,000 5,000 10,000 10,000 2,000 10,000 1,000 2,000
Table 27. Emission spectrographic results from the analysis of the -20/+60 sieve fraction of Rabbit Creek core [Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data] Field (.05) (.05) (.02) (.002) (200) (10) (10) (20) (1) (10) (20) (10) (10) (5) (5) (10) No. Ca% Fe% Mg% Na% P% Ti% Ag As Au B Ba Be Bi Cd Co Cr Cu Ga Ge N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N
Table 27. Emission spectrographic results from the analysis of the -20/+60 sieve fraction of Rabbit Creek core [Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data] Field No. (05) La N N N N N N N N N N N N N N N (10) Mn (5) Mo N N N N N N N N N N N N N N N N N N N (20) Nb N N N N N N N N N N N N N N N N (5) Ni (10) Pb N N N N N N N N (100) Sb N N N N N N N N N N N N N N N N N N N N N (5) Sc (10) Sn N N N N N N N N N N N N N N N N N N N N N (100) Sr N N N N N N N N N N N (100) Th N N N N N N N N N N N N N N N N N N N N N (10) (20) W N N N N N N N N N N N N N (10) Y (200) Zn N N N N N N N N N N N N N N N N (10) Zr
Table 28. Emission spectrographic results from the analysis of the -100/+250 sieve fraction of Rabbit Creek core ICa, Fe, Mg, Na, P, and Ti reported 1n percent, all other elements reported 1n ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data) Field No. (.05) Ca% (.05) Fe% (.02) Mg% Na% P% N N N N N N N N N N N N N N N N N N N N N (.002) Ti% Ag N N N N N N (200) As N N N N N N N N N N N N N N N N (10) Au N N N N N N N N N N N N N N N N N N N N N (10) B (20) Ba (1) Be N N N N N N N N (10) Bi N N N N N N N N N N N N N N N N N N N N N (20) Cd N N N N N N N N N N N N N N N N N N N N N (10) Co (10) Cr (5) Cu (5) (10) Ga Ge N N N N N N N N N N N N N N N N N N N N N
Table 28. Emission spectrographic results from the analysis of the -100/+250 sieve fraction of Rabbit Creek core [Ca, Fe, Mg, Na, P, and Ti reported In percent, all other elements reported 1n ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. (05) La N N N N N N N N N N N N N N (10) Mn (5) Mo N N N N N N N N N N N N N N N N (20) Nb N N N N N N N N N N N N N N (5) Ni (10) Pb N N N N N N N (100) Sb N N N N N N N N N N N N N N N N N N N N N (5) Sc (10) Sn N N N N N N N N N N N N N N N N N N N N N (100) Sr N N N N N N N N (100) Th N N N N N N N N N N N N N N N N N N N N N (10) (20) W N N N N N N N N N N N N N (10) Y (200) Zn N N N N N N N N N N N N N N N N N N N N N (10) Zr
Table 29. Emission spectrographic results from the analysis of the -250 sieve fraction of Rabbit Creek core (Ca, Fe, Mg, Na, P, and Ti reported 1n percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. (.05) Ca% (.05) Fe% (.02) Mg% Na% P% N N N N N N N N N N N N N N N N N N N N N (.002) Ti% Ag N N N N N N N N N N N N N N N N N N N (200) As N N N N N N N N N N N N N N N N N (10) Au N N N N N N N N N N N N N N N N N N N N N (10) B (20) Ba (1) Be N N N N N N (10) Bi N N N N N N N N N N N N N N N N N N N N N (20) Cd N N N N N N N N N N N N N N N N N N N N N (10) Co N N (10) Cr (5) Cu (5) (10) Ga Ge N N N N N N N N N N N N N N N N N N
Table 29. Emission spectrographlc results from the analysis of the -250 sieve fraction of Rabbit Creek core [Ca, Fe, Mg, Na, P, and T1 reported 1n percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. (50) La N N N N N N N N N N N N N N N N (10) Mn (5) Mo N N N N N N N N N N N N N N N N N N (20) Nb N N N N N N N N N N N N N N N N N (5) N1 (10) Pb N N (100) Sb N N N N N N N N N N N N N N N N N N N N N (5) Sc N (10) Sn N N N N N N N N N N N N N N N N N N N N N (100) Sr N N N N N N N N N (100) Th N N N N N N N N N N N N N N N N N N N N N (10) (20) W N N N N N N N N N N N N N N N (10) Y (200) Zn N N N N N N N N N N N N N N N N N N N (10) Zr
Table 30. Emission spectrographic results from the analysis of the whole clasts from Rabbit Creek core [Ca, Fe, Mg, Na, P, and T1 reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data] Field No. 14A 14B 15A 15D 15E 16A 16B 17A ISA 18B 19A 19B 21A 21B 21D (.05) Ca% (.05) Fe% (.02) Mg% Na% N N N N N N N N N N N G5 G5 N N N N N P% N N N N N N N N N N N N N N N N N (.002) T1% Gl Ag N N N N N N (200) As N N N N N N N N N N N N N N N (10) Au N N N N N N N N N N N N N N N N N N N N N N N (10) B (20) Ba (1) Be N N N N N N N N N N N N N N N (10) Bi N N N N N N N N N N N N N N N N N N N N N N N (20) Cd N N N N N N N N N N N N N N N N N N N N N N N (10) Co N N N N N N N N N N N N (10) Cr (5) Cu (5) Ga N N N N N N N (10) Ge N N N N N N N N N N N N N N N N N N
Table 30. Emission spectrographic results from the analysis of the whole clasts from Rabbit Creek core Continued [Ca, Fe, Mg, Na, P, and T1 reported 1n percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. 14A 14B 15A 15E 16A 16B 3 16D 17A ISA 18B 18D 19A 19B 21A 21B 21D (50) La N N N N N N N N N N N N N N N N (10) Mn G5000 (5) Mo N N N N N N N N N N N N N N N N N N N N N N (20) Nb N N N N N N N N N N N N N N N N N N N N (5) N1 N (10) Pb N N N N N N N N N N N N N (100) Sb N N N N N N N N N N N N N N N N N N N N N N N (5) Sc N N N N N N N N (10) Sn N N N N N N N N N N N N N N N N N N N N N N (100) Sr N N N N N N N N N N N (100) Th N N N N N N N N N N N N N N N N N N N N N N N (10) (20) W N N G10000 N N N N N N N N N N N N N (10) Y (200) Zn N N N N N N N N N N N N N N N N N N N N N (10) Zr
Table 30. Emission spectrographic results from the analysis of the whole clasts from Rabbit Creek core Continued ICa, Fe, Mg, Na, P, and Ti reported 1n percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. 5B 7A 8A 9A 9D IDA 10B 11A 11B 12A 12B 13A 13B 15B 17B (.05) Ca% (.05) Fe% (.02) Mg% Na% G5 G5 N N PX N N N N N N N N N N N (.002) T1X Gl Gl Gl Ag N N N N N (200) As N N N N N N N N N N N N N N N N N N (10) Au N N N N N N N N N N N N N N N N N N N N (10) B (20) Ba G5000 (1) Be N N N N N N N (10) Bi N N N N N N N N N N N N N N N N N N N N (20) Cd N N N N N N N N N N N N N N N N N N N N (10) Co N N N N N N N N N N (10) Cr (5) Cu (5) (10) Ga Ge N N N N N N N N N N N N N N N N N N N N N N N N N N N N
Table 30. Emission spectrographic results from the analysis of the whole clasts from Rabbit Creek core Continued (Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data] Field No. 5B 7A 8A 9A IDA 10B a HA 11B 12A 12B ISA 13B 15B 17B (50) La N N N N N N N N N N N N N N N N (10) Mn G5000 (5) Mo N N N N N N N N N N N N N N N N N (20) Nb N N N N N N N N N N N N N N N N N N (5) Ni (10) Pb N N N N N N N N (100) Sb N N N N N N N N N N N N N N N N N N N (5) Sc N N N (10) Sn N N N N N N N N N N N N N N N N N N N N (100) Sr N N N N (100) Th N N N N N N N N N N N N N N N N N N N N (10) (20) W N N N N N N N N N N N N N N N N N N N N (10) Y (200) Zn N N N N N N N N N N N N N N N N N (10) Zr
Table 30. Emission spectrographic results from the analysis of the whole clasts from Rabbit Creek core Continued [Ca, Fe, Mg, Na, P, and Ti reported 1n percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. 1A IB ID 2A 3A 3B 3D 4A 4B 4D 5A 5D 6A 7B SB 9B (.05) Ca% (.05) Fe% (.02) Mg% Na% N N N N N N G5 N P% N N N N N N N N N (.002) Ti% Ag N N N N N N N N (200) As N N N N N N N N N N N N N N N N N (10) Au N N N N N N N N N N N N N N N N N N N (10) B (20) Ba (1) Be N N N N N N N N N N N N N N (10) Bi N N N N N N N N N N N N N N N N N N N (20) Cd N N N N N N N N N N N N N N N N N N N (10) Co N N N N N N N N N N N (10) Cr (5) Cu N (5) (10) Ga Ge N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N
Table 30. Emission spectrographic results from the analysis of the whole clasts from Rabbit Creek core Continued |Ca, Fe, Mg, Na, P, and T1 reported In percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. 1A IB ID 2A 3A 3B 3D en 4A 4B 4D 5A 5D 6A 7B SB 9B (50) La N N N N N N N N N N N N N N (10) Mn (5) Mo N N N N N N N N N N N N N N N N N (20) Nb N N N N N N N N N N N N N N N N N N (5) Ni N (10) Pb N N N N N N N N N N N N N N N (100) Sb N N N N N N N N N N N N N N N N N N (5) Sc N N N N N N N N N (10) Sn N N N N N N N N N N N N N N N N N N N (100) Sr N N N N N (100) Th N N N N N N N N N N N N N N N N N N N (10) (20) W N N N N N N N N N N N N N N N N N (10) Y N N N (200) Zn N N N N N N N N N N N N N N N N N N (10) Zr
Atomic emission spectrography for the determination of 35 elements in oxalic acid leachates An oxalic acid leach was used in conjunction with de-arc emission spectrography to analyze four of the core fractions (-20/+60 ground, -20/+60 unground, -100/+250, and -250) for metals tied up in secondary amorphous Fe and Mn oxide coatings (tables 31-34). Fifty ml of 5 percent oxalic acid solution was added to 5 gm of sample the solution was then placed on a heating plate and brought to a boil for 5 minutes. The solution was filtered and the filtrate was taken to dryness. The resulting solid was placed in a muffle furnace and heated to 450 °C for 4 hrs., during this step the crystalline oxalic acid is driven off as oxalate. The prepared sample was then pulverized and a 5 mg sample was analyzed spectrographically for 35 elements. (Grimes and Marranzino, table 26). Tables 31-34 contain the results from the analysis of the oxalic acid leachates, Au, Bi, Cd, Th, and Y were analyzed; however, these elements do not appear in the table because they were not detected at the respective lower limits of determination in any of the samples. Atomic emission spectrography for the determination of 35 elements in heavy- mineral concentrates from drill core The C2 and C3 fractions of the prepared heavy-mineral concentrates (-20/+60 and -100/+250) were analyzed spectrographically. The method used is similar to the one described by Grimes and Marranzino (table 26) except that a 5 mg sample charge is used and the sample charge is buffered with 25 mg of 4:1 graphite-quartz mixture. The results from the analysis of the heavy-mineral concentrates are presented in tables 35-38 of the 35 elements reported Au, Bi, Cd, Sn, and Th do not appear in the tables, these elements were looked for but were not detected at their respective lower limits of determination in any of the samples. Explanation of emission spectrographic data tables All the emission spectrographic data tables are presented such that the first columns contains the sample number and the balance of the columns the concentration of that element which appears at the head of each column. Elements reported in percent include Ca, Fe, Mg, Na, P, and Ti, all other elements are reported in parts per million (ppm). Sometimes a qualifier (N, L, G) is used in place of a real value, N indicates an element was looked for but was not detected at the lower limit of determination, L indicates that the element was present at a concentration below the lower limit of determination, and G indicates that the element was detected at a concentration greater than the upper limit of determination.
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Table 31.~Emission spectrographic results from the analysis of the -20/+60 ground sieve fraction oxalic add leachate Contlnued [Ca, Fe, Mg, Na, P, and Ti reported 1n percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. (100) La N N N N N N N N N N N
N N N N N N N N N (20) Mn
G( 10000) G( 10000) (10) Mo N
(50) Nb N N N N N (10) N1
(20) Pb N N N N N N N N N N
N N N N (200) Sb N N N N N N N N N N N
N (10) Sc N N N N N N N N N N N N N N N N (20) Sn N N N N N N N N N N N N N N N N N N N N (200) Sr N N N N
N N (200) Th N N N N N N N N N N N
N N N N N N N N N (20)
(50) W N N N
(20) Y N N N N N N N N
N N N N N N N N N (500) Zn N N N N N N (20) Zr N N N N N N N N N N
N N (5) (20) Pd Pt N N N N N N N N N N
N N N N N N N N N N N N N N N N N N N N
N N N N N N N N N
Table 32. Emission spectrographic results from the analysis of the -20/+60 unground sieve fraction oxalic add leachate [Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported 1n ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. Ca % Fe % (.05) Mg % Na % N P % (.005) T1 % (1) Ag N N N N N N N N N N N N N N N N N N N (500) As N N N N N N N N N N (20) Au N N N N N N N N N N N N N N N N N N N N N (20) B (50) Ba (2) Be (20) B1 N N N N N N N N N N N N N N N N N N N N N (50) Cd N N N N N N N N N N N N N N N N N N N N N (20) Co (20) Cr (10) Cu (10) Ga (20) Ge N N N N N N N N N N N N
Table 32. Emission spectrographic results from the analysis of the -20/+60 unground sieve fraction oxalic acid leachate Continued [Ca, Fe, Mg, Na, P, and T1 reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field (100) (20) (10) (50). (10) (20) (200) (10) (20) (200) No. La Mn Mo Nb Ni Pb Sb Sc Sn Sr (200) (20) (50) (20) Th W Y (500) (20) (5) (20) Zn Zr Pd Pt N N N N N N N N N N N N N N N N N N N N N G(IOOOO) G(IOOOO) G(IOOOO) G(IOOOO) G( 10000) G(IOOOO) N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N
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Table 33. Emission spectrographlc results from the analysis of the -100/+250 sieve fraction oxalic add leachate Continued [Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. (100) La N N N N N N N N N N N
N N N N N N N N N (20) Mn G( 10000) (10) Mo
(50) Nb N N N N
N (10) Ni (20) Pb N N N N N N N N
N N N N N (200) Sb N N N N N N N N N N N
N N (10) Sc N N N N N N N N N N N
N N N N N (20) Sn N N N N N N N N N N N
N N N N N N N N (200) Sr N N
N N N (200) Th N N N N N N N N N N N N N N N N N N N N (20)
(50) W N N N N
(20) Y N N N N N N N N N N N N N N N N N N N N (500) Zn
(20) Zr N N N N N N N N
N (5) (20) Pd Pt N N N N N N N N N N N
N N N N N N N N N N N N N N N N N N N N
N N N N N N N N N
Table 34. Emission spectrographic results from the analysis of the -250 sieve fraction oxalic add leachate [Ca, Fe, Mg, Na, P, and T1 reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. Ca % Fe % (.05) Mg % Na %
P % N N N N N (.005) T1 %
(1) Ag N N N N N N N N N N
N N N N N N N (500) As N N N N N N N N N N N
(20) Au N N N N N N N N N N N
N N N N N N N N N (20) (50) (2) B Ba Be 150 G(IOOOO) 30 G( 10000)
(20) Bi N N N N N N N N N N N
N N N N N N N N N (50) Cd N N N N N N N N N N N
N N N N N N N N N (20) Co
(20) Cr
(10) Cu
(10) Ga (20) Ge N N N N N N N N N N N N N N
Table 34. Emission spectrographic results from the analysis of the -250 sieve fraction oxalic add leachate Continued [Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data] Field No. (100) La N N N N N N N N N N N N N N N N N N N N (20) Mn G( 10000) (10) Mo (50) Nb N N N N N N N N N N N N N N (10) Ni
(20) Pb N N N N N N N N N N N
N N N N N (200) Sb N N N N N N N N N N
N N N N (10) Sc N N N N N N N N N N N
N N N N N N N N N (20) Sn N N N N N N N N N N N
N N N N N N N N (200) Sr N N N N N N
N N N N N (200) Th N N N N N N N N N N N
N N N N N N N N N (20)
(50) w N N N
(20) Y N N N N N N N N N N N
N N N N N N N N N (500) Zn N N N N N
N N N (20) Zr N N N N N N N N N
N N (5) (20) Pd Pt N N N N N N N N N N N
N N N N N N N N N N N N N N N N N N N N
N N N N N N N N N
Table 35.--Spectrographic results from the analysis of the -20/+60 fraction C-2 heavy-mineral concentrate from drill core [Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. Ca % Fe % (.05) Mg % Na % N N N N N N N N P % N N N N N N N N N N N N N N (.005) T1 % (1) Ag N N N N N N N N N N N N N N N N N N N N (500) As N N N N N N N (20) Au N N N N N N N N N N N N N N N N N N N N N (20) B N (50) Ba G10000 (2) Be (20) B1 N N N N N N N N N N N N N N N N N N N N N (50) Cd N N N N N N N N N N N N N N N N N N N N N (20) Co (20) Cr (10) (10) Cu Ga N N N N N N N N N N N N N N N N N N N N N (20) Ge N N N N N N N N N N N N N N N N N N N N N
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Table 36. Spectrographic results from the analysis of the -207+60 fraction C-3 heavy-mineral concentrate from drill core [Ca, Fe, Mg, Na, P, and T1 reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. Ca % Fe %
(.05) Mg %
Na % N N N N N N N N N N N N
N P %
(.005) T1 % G2
(1) Ag N N N N N N N N N
(500) As N N N N N N N N N N N N N N N N N N
N (20) Au N N N N N N N N N N N N N N N N N N N
N (20) B
(50) Ba G100000 G10000 G10000 G10000 G10000
(2) Be N N N N N N N N N N N N N N
(20) Bi N N N N N N N N N N N N N N N N N N N
N (50) Cd N N N N N N N N N N N N N N N N N N N
N (20) Co N N N N N N N N N N N N N N N
N (20) Cr
(10) Cu
(10) Ga N N N N N N N N N N N N N N N N N
N (20) Ge N N N N N N N N N N N N N N N N N N N
N
Table 36.~Spectrograph1c results from the analysis of the -20/+60 fraction C-3 heavy-mineral concentrate from drill core Continued [Ca, Fe, Mg, Na, P, and T1 reported 1n percent, all other elements reported In ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data] 00o Field No. (100) La
(20) Mn N
(10) Mo N N N N N N N N N N N N N N N N N
N (50) Nb N N N N N N N N N N N N N N N N N N
N (10) Ni (20) Pb N N N N N N N N N N N N N N N N
N (200) Sb N N N N N N N N N N N N N N N N N N N (10) Sc N N N N
(20) Sn N N N N N N N N N N N N N N N N N N N N (200) Sr (200) Th N N N N N N N N N N N N N N N N N N N
N (20) (50) W N N N N N N N N N N N N N N N N N N
N (20) Y
(500) Zn N N N N N N N N N N N N N N N N N N N
N (20) Zr
Table 37. Spectrographic results from the analysis of the -100/+250 fraction C-2 heavy-nlneral concentrate fron drill core [Ca, Fe, Mg, Na, P, and T1 reported in percent, all other elements reported 1n ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data] Field No. Ca %
Fe % (.05) Mg %
Na % N
N N N N N N N N P % N N N N N N N N N
N N N (.005) Ti % G2 G2 G2 G2 G2 G2 G2 G2
G2 G2 G2 G2 G2 G2 (1) Ag N N N N N N N N N N N N
N N N N N N N N (500) As N N N N N N N N N N N N
(20) Au N N N N N N N N N N N N
N N N N N N N N (20) B
(50) Ba
G10000 G10000 (2) Be N
(20) Bi N N N N N N N N N N N N
N N N N N N N N (50) Cd N N N N N N N N N N N N
N N N N N N N N (20) Co
(20) Cr
(10) Cu
(10) Ga N N N N N N N N N N N N
N N N N N N N N (20) Ge N N N N N N N N N N N N
N N N N N N N
Table 37.~Spectrograph1c results from the analysis of the -100/+250 fraction C-2 heavy-mineral concentrate from drill core Continued [Ca, Fe, Mg, Na, P, and T1 reported 1n percent, all other elements reported 1n ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] PO Field No. (100) La N
N (20) Mn G10000 G10000 G 10000 G10000
G10000 G10000 G10000 G10000 (10) Mo N N N N N N N N N N
N N N N N N N (50) Nb N (10) Ni (20) Pb
(200) Sb N N N N N N N N N N N N
(10) Sc
(20) Sn N N N N N N N N N N N N N N N N N N N N (200) Sr N
N N N (200) Th N N N N N N N N N N N
N N N N N N N N (20)
(50) w N N N N N N N N N N N N
N N N (20) Y
(500) Zn N N N N N
N N N N N N (20) Zr G2000 G2000
G2000 G2000
Table 38. Spectrographic results from the analysis of the -100/+250 fraction C-3 heavy-ailneral concentrate from drill core [Ca, Fe, Mg, Na, P, and Ti reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; -- no data] Field No. Ca % Fe % (.05) Mg % Na % N N N N N N N N N N N N N N N N N N N N P % N (.005) Ti % G2 (1) Ag N N N N N N N N N N N N N N N N N. N N (500) As N N N N N N N N N N N N N N N N N N N N (20) Au N N N N N N N N N N N N N N N N N N N N (20) B (50) Ba G10000 G 10000 G10000 G10000 G 10000 G10000 G1000 G1000 G1000 (2) Be N N N N N N N (20) Bi N N N N N N N N N N N N N N N N N N N N (50) Cd N N N N N N N N N N N N N N N N N N N N (20) Co N N N N N N N N N N N N N N (20) Cr (10) Cu (10) Ga N N N N N N N N N N N N N N N N (20) Ge N N N N N N N N N N N N N N N N N N N N
Table 38.--Spectrographlc results from the analysis of the -100/+250 fraction C-3 heavy-mineral concentrate from drill core Continued [Ca, Fe, Mg, Na, P, and T1 reported in percent, all other elements reported in ppm; N, not detected; L, detected at a level below the limit of determination; G, detected at a level greater than the upper limit of determination; no data)
Field No. (100) La N N (20) Mn G 10000 (10) Mo N N N N N N N N N N N N N N N N N N N (50) Nb N N N N N N N N N N N N N N N N N (10) N1 N N N N N (20) Pb N N N N N N N N N N N N (200) Sb N N N N N N N N N N N N N (10) Sc N N N (20) Sn N N N N N N N N N N N N N N N N N N N N (200) Sr (200) Th N N N N N N N N N N N N N N N N N N N N (20) (50) W N N N N N N N N N N N N N N N N (20) Y (500) Zn N N N N G2000 N N N N (20) Zr G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000 G2000
References Chao, T.T., 1984, Use of partial dissolution techniques in geochemical exploration: Journal of Geochemical Exploration, v. 20, p. 101-135. Chao, T.T., and Zhou, Liyi, 1983, Extraction techniques for selective dissolution of amorphous iron oxides from solids and sediments: Soil Science Society of America Journal, p. 225-232. Cherry, J.A., Shaikh, A.U.,, Talman, D.E., and Nicholson, R.V., 1979, Arsenic species as an indicator of redox conditions in groundwater: Journal of Hydrology, v 43, p. 373-392. Ficklin, W.H., 1983, Separation of arsenic(III) and arsenic(V) in groundwaters by ion-exchange: Talanta 30(5), p. 371-373. Ficklin, W.H., and Callender, Edward, 1987, Speciation of arsenic in sediments and intersitial water from the Cheyene River Arm of Lake Oahe, South Dakota, iji Mallard, G.E., ed., U.S. Geological Survey Toxic Substances Hydrology Program Surface-water contamination, Proceedings of the Technical Meeting, Denver, CO, Feb. 2-4: U.S. Geological Survey Open- File Report 87-764, Chapter A, p. 49-54. Fiedman, Irving and Denton, E.H., 1975, A portable helium sniffer: U.S. Geological Survey Open-File Report 75-732, 6 p. Grimes, D.J., and Marranzino, A.P., 1968, Direct-current arc and alternating- current spark emission spectrographic field methods for the semi- quantitative analysis of geologic mterials: U.S. Geological Survey Circular 591, 6 p. Hinkle, M.E. and Dilbert, C.A., 1984, Gases and trace elements in soils at the North Silver Bell Deposit, Pima County, Arizona: Journal of Geochemical Exploration, v. 20, no. 3, p. 323-336. Hinkle, M.E., 1986, Using volatile constituents of soils and soil gases to determine the presence of copper-zinc ore bodies at Johnson Camp, Arizona: Journal of Geophysical Research, v. 91, no. B12, p. 12359- Hinkle, M.E. and Botinelly, Theodore, 1988, Concentrations of He, C02 and Q£ in soil gases, and soil types at Roosevelt Hot Springs Known Geothermal Resource Area, Utah: U.S. Geological Survey Open-File Report 88-259, 30 p. Hinkle, M.E., 1988, A tabulation of meteorological variables and concentrations of helium, carbon dioxide, oxygen, and nitrogen in soil gases collected regularly from four sites at the Roosevelt Hot Springs Known Geothermal Resource Area, Utah: U.S. Geological Survey Open-File Report 88-685, 30 p. Hopkins, D.M., 1977, An improved ion-selective electrode method for the rapid determination of fluoride in rocks and soils: U.S. Geological Survey Journal of Research, v. 5, no. 5, p. 589-593. Kennedy, K.R., and Crock, J.G., 1987, Determination of mercury in geological materials by continuous flow, cold-vapor, atomic absorption spectrophotometry: Analytical Letters, v. 20, p. 899-908. O'Leary R.M. and Meier, A.L., 1986, Analytical methods used in geochemical exploration: U.S. Geological Survey Circular 738, 25 p. O'Leary, R.M., and Meier, A.L., 1986, Analytical methods used in geochemical exploration, 1984: U.S. Geological Survey Circular 948, 48 p. O'Leary, R.M., and Viets, J.G., 1986, Determination of antimony, arsenic, bismuth, cadmium, copper, lead, molybdenum, silver, and zinc in geologic materials by atomic absorption spectrometry using a hydrochloric acid and hydrogen peroxide digestion: Atomic Spectroscopy, v. 7, p. 4-8. Welsch, E.P., 1983, A rapid geochemical spectrophotometric determination of tungsten with dithiol: Talanta, v. 30, p. 876-878.