Correlation chart of Pennsylvanian rocks in Alabama, Tennessee, Kentucky, Virginia, West Virginia, Ohio, Maryland, and Pennsylvania showing approximate position of coal beds, coal zones, and key stratigraphic units
<p>The Appalachian basin, one of the largest Pennsylvanian bituminous coal-producing regions in the world, currently contains nearly one-half of the top 15…
Public-domain full text preserved in the Mountain Man Mining Library. Original source: pubs.usgs.gov.
Correlation Chart of Pennsylvanian Rocks in Alabama, Tennessee, Kentucky, Virginia, West Virginia, Ohio, Maryland, and Pennsylvania Showing Approximate Position of Coal Beds, Coal Zones, and Key Stratigraphic Units By Leslie F. Ruppert, Michael H. Trippi, and Ernie R. Slucher Chapter D.2 of Coal and Petroleum Resources in the Appalachian Basin: Distribution, Geologic Framework, and Geochemical Character Edited by Leslie F. Ruppert and Robert T. Ryder Professional Paper 1708 U.S. Department of the Interior U.S. Geological Survey
Suggested citation: Ruppert, L.F., Trippi, M.H., and Slucher, E.R., 2014, Correlation chart of Pennsylvanian rocks in Alabama, Tennessee, Kentucky, Virginia, West Virginia, Ohio, Maryland, and Pennsylvania showing approximate position of coal beds, coal zones, and key stratigraphic units, chap. D.2 of Ruppert, L.F., and Ryder, R.T., eds., Coal and petroleum resources in the Appalachian basin; Distribution, geologic framework, and geochemical character: U.S. Geological Survey Professional Paper 1708, 9 p., http://dx.doi.org/10.3133/pp1708D.2.
Contents Introduction 1 Geology of the Appalachian Basin and the Pennsylvania Anthracite Region 2 Coal Fields of the Appalachian Basin 3 Coal Production Within the Appalachian Basin 3 Pennsylvanian Strata Within the Appalachian Basin and the Pennsylvania Anthracite Fields 3 Lower Pennsylvanian Rocks 4 Middle Pennsylvanian Rocks 5 Upper Pennsylvanian Rocks 5 References Cited 6 Figures [As separate files; click link to access]
1. Chronostratigraphic correlation chart of coal-bearing Pennsylvanian rocks in the Appalachian basin and Pennsylvania Anthracite region showing approximate position of coal beds, coal zones, and key stratigraphic units.
2. Map showing the location of the Appalachian basin coal regions, the Pennsylvania Anthracite region, and designated coal fields.
3. Map showing the location of major structural features and the coal-bearing regions of the Appalachian basin, including the Black Warrior basin and the Pennsylvania Anthracite region.
Correlation Chart of Pennsylvanian Rocks in Alabama, Tennessee, Kentucky, Virginia, West Virginia, Ohio, Maryland, and Pennsylvania Showing Approximate Position of Coal Beds, Coal Zones, and Key Stratigraphic Units By Leslie F. Ruppert,1 Michael H. Trippi,1 and Ernie R. Slucher1 Introduction The Appalachian basin, one of the largest Pennsylvanian bituminous coal-producing regions in the world, currently contains nearly one-half of the top 15 coal-producing States in the United States (Energy Information Agency, 2006). Anthracite of Pennsylvanian age occurs in synclinal basins in eastern Pennsylvania, but production is minimal. A simplified correlation chart was compiled from published and unpub lished sources as a means of visualizing currently accepted stratigraphic relations between the rock formations, coal beds, coal zones, and key stratigraphic units in Alabama, Tennes see, Kentucky, Virginia, West Virginia, Ohio, Maryland, and Pennsylvania. The thickness of each column is based on chronostratigraphic divisions (Lower, Middle, and Upper Pennsylvanian), not the thickness of strata. Researchers of Pennsylvanian strata in the Appalachian basin also use bio stratigraphic markers and other relative and absolute geologic age associations between the rocks to better understand the spatial relations of the strata. Thus, the stratigraphic correla tion data in this chart should be considered provisional and will be updated as coal-bearing rocks within the Appalachian coal regions continue to be evaluated. Most geologic formations are identified and defined by the distinctive lithologic features they contain. However, formations of Pennsylvanian age in the Appalachian basin and the Pennsylvania Anthracite region have traditionally been described and named to reflect the presence or absence of economic coal beds and coarse-grained sandstone units, most of which have since been proven to be locally or regionally discontinuous (Ruppert and Rice, 2001). Many of the strati graphic names and boundaries used for the coals and other geologic units in the Pennsylvanian rocks differ between States or regions (fig. 1). Because local and regional strati graphic complexities occur within some States, a multiplicity of State-specific names is introduced that may be confusing to those conducting regional geologic assessments in the basin. Nonetheless, many of these stratigraphic names and boundaries have some elements that allow for regional strati graphic correlation. For instance, many coals in the northern Appalachian basin coal region are easier to trace over greater distances than coals in the central and southern Appalachian basin coal regions (fig. 2). The Upper Pennsylvanian Pitts burgh coal bed (fig. 1) of the northern Appalachian basin coal region, for example, occurs as a synchronogenic bed deposited on a laterally continuous surface of sediments (Cross, 1954; Tewalt and others, 2001). The base of the Pittsburgh coal bed is designated as the contact between the Conemaugh Group (Upper Pennsylvanian) and the overlying Monongahela Group in western Pennsylvania, western Maryland, Ohio, and West Virginia (fig. 1). Therefore, in areas where the Pittsburgh coal bed is present, there is little controversy over its position or the placement of the boundary between the Conemaugh and Monongahela Groups. In other regions of the basin, group and formation boundaries are more difficult to identify over extensive areas. One example is the placement of the contact between the New River Formation and the overlying Kanawha Formation—a boundary that is not easily defined beyond the area where these units were first defined in West Virginia. At the type section of the Kanawha Formation, the base of the Lower Douglas coal zone (fig. 1) defines the contact between the Kanawha Formation and the underlying New River Formation (Rice and others, 1994b). However, subsequent mapping has demonstrated that the Lower Douglas coal zone is regionally discontinuous and in many parts of West Virginia is absent (Blake and others, 2002). Where absent, the Nuttall Sandstone Member of the underlying New River Formation sometimes occurs in the stratigraphic position of the Lower Douglas 1U.S. Geological Survey, Reston, Va.
2 Coal and Petroleum Resources in the Appalachian Basin coal zone. Yet, even the Nuttall Sandstone Member has been found to be regionally discontinuous and of varying thickness throughout its extent, features that hinder its use as a regional stratigraphic marker bed in the Appalachian basin. Because of the many names used to identify individual coal beds and coal zones in the historic Appalachian basin coal-mining districts, coal bed designations may differ even more than stratigraphic nomenclature. In eastern Kentucky, northwest of the Pine Mountain thrust fault on the Cumberland overthrust sheet, for example, coal beds or coal zones equiva lent to the Lower Elkhorn coal zone (within the Pikeville For mation) are identified also as the Eagle coal zone, Pond Creek coal zone, and Blue Gem coal bed (fig. 1). Southeast of the Pine Mountain thrust fault, yet still in Kentucky, equivalent coals in this same interval are known as the Imboden and Rich Mountain. Moreover, this same interval of coal is identified as the Blue Gem coal in Tennessee, the Imboden coal bed or Campbell Creek or Pond Creek coal zones in Virginia, and the Eagle coal zone in West Virginia. Geology of the Appalachian Basin and the Pennsylvania Anthracite Region The proto-Appalachian basin first developed on Mesopro terozoic (1.1 billion years old) continental crust that extended along the thinned continental margin of Iapetus, the protoAtlantic Ocean. During Mississippian time, the basin was located at about 20° S. latitude, but by Pennsylvanian time had migrated north and was mostly in the equatorial region (Cecil, 1990). Between 330 and 265 million years ago, the Appalachian Mountains were formed by the collision of the southern part of Laurentia (composed of the North American and Greenland continental plates) and Gondwana (composed of the African, South American, Indian, Antarctica, Australian, New Guinean, and New Zealand continental plates) (Hatcher and others, 1989). The collision caused downwarping, or subsidence, west of the mountains and formed an elongated foreland basin (Hatcher and others, 1989). The newly created accommodation space within the Appalachian basin was filled with a wedge of clastic sediments that generally thickened southeastward towards the pre-thrusting axis of the basin. The axial region has been broken by Appalachian thrust sheets so that now much of the younger part of the stratigraphic section has been uplifted and eroded away. However, the axial region is inferred to have been east of, and parallel to, the eastern edge of the present-day Pennsylvanian outcrop belt. The west ern edge of the basin is marked by the Cincinnati arch (fig. 3), which, in part, separates the Appalachian foreland basin from the Eastern Interior basin of the midcontinent. It is believed that some Pennsylvanian sediments may have been eroded from the newly formed Appalachian Mountains, transported across the Cincinnati arch, and deposited into the Eastern Interior basin (Siever and Potter, 1956; Rice and Schwietering, 1988). Presently, the eastern limit of Pennsylvanian rocks in the Appalachian basin is generally defined by the west- and northwest-facing northeast-trending Allegheny structural front (fig. 3), a feature that marks the boundary between the Appalachian Plateaus and the Valley and Ridge physiographic provinces. The Black Warrior basin of Alabama is also a late Paleo zoic foreland basin that extends westward into the subsurface of Mississippi (fig. 3). This basin formed in the structural recess between the Appalachian and Ouachita fold and thrust belts (Ryder, 1987; Pashin, 2004). The southeastern edge of the Black Warrior coal basin is strongly deformed into a series of synclinal basins that delineate the western edge of the Appalachian fold belt (Davis and Ehrlich, 1974; Thomas, 1988). Cretaceous and Tertiary coastal sediments of the Mis sissippi embayment and the Gulf Coastal Plain conceal most of the Pennsylvanian strata to the south and west (Thomas, 1988). Abundant Lower Pennsylvanian coal resources of the Black Warrior, Cahaba, Coosa, Sand Mountain, and Lookout Mountain fields have historically been included within the Appalachian basin coal resource base as part of the southern Appalachian basin coal region (fig. 2). That traditional treat ment continues in this paper. The oldest preserved Pennsylvanian rocks are found in three areas within the Appalachian basin. They are (1) the deepest part of the central Appalachian basin coal region in southeastern West Virginia and western Virginia, near Pocahontas, Va.; (2) the Eastern Middle, Western Middle, and Southern fields of the Pennsylvania Anthracite region in eastern Pennsylvania; and (3) the Black Warrior, Cahaba, and Coosa fields of Alabama (fig. 2). Near Pocahontas, Va., the maximum thickness of the Pocahontas Formation in this area exceeds 700 feet (ft) (Englund, 1979). A pre-Pennsylvanian unconformity exists in the Black Warrior coal basin. However, in this region, greater subsidence preserved Lower Pennsyl vanian sediments that exceed 5,700 ft in maximum thickness (R.E. Carroll, Geological Survey of Alabama, written com mun., 2006). The youngest Pennsylvanian (and overlying Perm ian) strata are preserved in the northeast-trending Dunkard basin, which is found in the northern and central Appalachian basin coal regions (figs. 2 and 3). In general, Pennsylvanianage rocks slowly rise in elevation away from this structural axis—in all directions—and crop out at the surface around the perimeter of the Appalachian basin (Ruppert and Rice, 2001, and references contained therein). Sediments of Pennsylvanian age were deposited in many types of aqueous environments that range from piedmont and limnic settings to coastal settings containing deltaic channels, marshes, peat-forming swamps, lagoons, and shallow-marine embayments (Ferm and Horne, 1979; Donaldson and others, 1985; Englund and others, 1986; Slucher and Rice, 1994; Greb and others, 2004). During the Pennsylvanian, sediments derived from the newly formed Appalachian Mountains, and the Canadian craton to the north, prograded west, northwest,
Chapter D.2 Correlation Chart of Pennsylvanian Rocks in the Appalachian Basin 3 and south as fluvial channels and deltaic fans across a broad coastal plain. Periodically, especially during the Middle and early Late Pennsylvanian, shallow-marine incursions inun dated the coastal environments. The occurrences of these marine incursions may have been partly controlled by the waxing and waning of continental-scale glaciation in the southern hemisphere (Ruppert and Rice, 2001, and references contained therein), repetitive processes that affected eustatic levels worldwide. Coal Fields of the Appalachian Basin The Appalachian basin has informally been subdivided into three coal regions—the northern, central, and southern Appalachian basin coal regions—on the basis of characteris tics of the sediments and the coals that are found there (fig. 2). The three coal regions contain both formal and informal coal fields. Two types of coal fields occur in the northern Appala chian basin coal region (fig. 2): bituminous-rank fields and anthracite-rank fields. Bituminous-rank fields include the Main Bituminous field, the North-Central field, the Broad Top field, the Upper Potomac field (which includes the Lower and Upper Youghiogheny basins and the Castleman and Georges Creek basins), and the Northern West Virginia coal field. The coal-bearing region in Ohio is not subdivided into named coal fields or regions (fig. 2). Anthracite fields include the Western Northern field, the Southern and Northern fields, and the East ern Middle and Western Middle fields. These named anthracite coal fields occur only in the Valley and Ridge physiographic province but have historically been placed in the resource base of the northern Appalachian basin coal region. The central Appalachian basin coal region coal fields include the Southern West Virginia coal field, the Southwest Virginia coal field, the Eastern Kentucky coal field, and the Northern Tennessee coal field (fig. 2). Coal rank is generally medium- and high-volatile bituminous throughout the central region except in the southeastern part of the Southern West Virginia coal field (fig. 2), where coal rank is low-volatile bituminous. Coal fields of the southern Appalachian basin coal region include the Southern Tennessee coal field and the Black War rior field of Alabama. Coal rank is medium- and high-volatile bituminous in both coal fields (fig. 2). Four small coal fields occur east of the Black Warrior field: the Sand Mountain, Lookout Mountain, Cahaba, and Coosa fields of Alabama. Coal Production Within the Appalachian Basin Pennsylvanian coal in the Appalachian basin has been mined nearly continuously since the 18th century and was a major factor in the economic development and industrial growth of the Eastern United States. Over 36.3 billion short tons (BST) of coal have been mined in the basin over the last 215 years (see Tewalt and Ruppert, this volume, chap. D.4). The northern Appalachian basin coal region (fig. 2) is the largest historic producer (19.6 BST), followed by the central Appalachian basin coal region (16.7 BST), and the southern Appalachian basin coal region (1.9 BST) (Tewalt and Ruppert, this volume, chap. D.4). Although the northern Appalachian basin coal region is the overall largest producer of coal within the basin, coal production in the central Appalachian basin coal region has outpaced that of the northern region over the last three decades because of the increased demand for lowsulfur coal. See Milici and Polyak (this volume, chap. D.3) for a more detailed discussion of coal production within the basin. Pennsylvanian Strata Within the Appalachian Basin and the Pennsylvania Anthracite Fields Placement of the boundaries between Upper, Middle, and Lower Pennsylvanian rocks in the Appalachian basin tends to differ between States of the region because of various historic lithostratigraphic and economic subdivisions used to define coal-bearing intervals. For example, the boundary between Middle and Upper Pennsylvanian rocks is traditionally placed at the top of the Upper Freeport coal bed of the Allegheny Formation (Bradley, 1956). This usage coincides with the long-standing placement of the contact between the Allegheny Formation and the overlying Conemaugh Group at the top of the Upper Freeport coal bed. In areas where the Upper Free port coal bed is absent, the boundary between the Allegheny Formation and the Conemaugh Group is defined by a gradual change in the lithologic character of the rocks. Strata below the Upper Freeport coal bed consist, in general, of rocks that are mostly shades of gray and black in color, whereas rocks above the Upper Freeport coal bed commonly contain inter vals of red and green mudstone, shale, and siltstone. However, Phillips and Peppers (1984) discovered that the placement of this boundary was unsubstantiated by biostrati graphic criteria. They found that both the Upper Freeport and overlying Mahoning coal beds of the lower Conemaugh Group (see figure 1) are dominated by the presence of Lycospora, an important Early and Middle Pennsylvanian palynomorph. Fur thermore, the Brush Creek coal bed, the next persistent coal bed above the Mahoning coal bed in the lower Conemaugh Group of Ohio, Pennsylvania, and Maryland, rarely contains this palynomorph (abundance percent) (Phillips and Pep pers, 1984). Hence, on the basis of their analysis, the tradi tional stratigraphically based placement of the Middle-Upper Pennsylvanian boundary at the top of the Upper Freeport coal bed is untenable. Rather, the lower part of the overlying Conemaugh Group is clearly Middle Pennsylvanian in age,
4 Coal and Petroleum Resources in the Appalachian Basin and the boundary between Middle and Upper Pennsylvanian rocks occurs just above the Mahoning coal bed in the lower part of the Conemaugh Group (see Blake and others, 2002, and figure 1 of this report). In this report, we use the divisions of Blake and others (2002) for the Lower and Middle Pennsyl vanian boundary. The boundary between the top of Upper Pennsylvanian sediments and the base of the overlying Permian sediments has generally been placed in the lower part of the Dunkard Group, at the base of the Washington coal or, where it is absent, the stratigraphic position of the Washington coal. This has traditionally been supported by the occurrence of the fos sil plant Callipteris (Autunia) conferta, a diagnostic Permian seed fern in the seat rock of this coal bed (see Berryhill, 1963; Ruppert and Rice, 2001, and references contained within). However, spores found in coal beds in this interval only sup port a Late, but not latest, Pennsylvanian age (Clendening, 1974, 1975). Blake and others (2002) concluded that earlier workers (Berryhill, 1963; Havlena, 1975) may have placed unwarranted emphasis on first occurrences of extrabasinal forms such as Callipteris (Autunia) conferta now known to have been contemporaneous with, and sporadically occupying specific paleoenvironments within, typical Dunkard lowland flora settings in the Appalachian basin region. The Pennsylva nian-Permian transition in the Appalachian basin was a period of tectonically induced climatic change produced by the newly formed Appalachian Mountains during the Alleghany orogeny; thus, occurrences of these highly climate sensitive extrabasinal plant fossils are suspect. It is believed further age refinement will be possible if specific types of marine fossils can be identified within Dunkard rocks. Yet, to date, the only known marine or marginal marine fossils found in Dunkard strata are those with only limited biostratigraphical usefulness (Lingula, for example); thus, the exact age of the Dunkard Group cannot be refined beyond a Pennsylvanian to Permian age assignment (Martin, 1998; B.M. Blake, Jr., West Virginia Geologic and Economic Survey, oral commun., 2005). Lower Pennsylvanian Rocks Lower Pennsylvanian strata extend, in general, across the Appalachian basin as northwestward prograding, timetransgressive sequences with a depositional strike parallel to the Appalachian Mountains. The pre-Pennsylvanian unconfor mity that developed on Mississippian rocks in most regions of the basin formed an irregular surface, particularly along the western basin margins where deeply incised valleys developed in Mississippian rocks and controlled sedimentation patterns well into Middle Pennsylvanian time (Slucher and Rice, 1994). Many of these valleys are filled with hundreds of feet of Pennsylvanian-age coarse-grained clastic sediments —for example, the Livingston Conglomerate Member of Kentucky and the “Sharon” Conglomerate of southern Ohio. The con tact between these Pennsylvanian sediments and underlying Mississippian rocks is clearly erosional in most places in the basin. The Pocahontas Formation consists mostly of coalbearing sequences of carbonaceous shale and siltstone with minor sandstone and does not extend into the more distal parts of the basin beyond the Pocahontas area of Virginia (Englund, 1979). Northwest of Pocahontas, Va., Lower Pennsylvanian rocks in the central Appalachian basin coal region typi cally consist of thick sequences of conglomeratic quartzose sandstones that overlie units equivalent mostly to the upper part of the Pocahontas Formation (Greb and others, 2004). These younger strata reach a maximum thickness of more than 1,600 ft along the border between Virginia and Kentucky (Englund and others, 1979; Rice and others, 1979). Included in this interval of thick quartzose sandstones are the New River, Lee, and Norton Formations and the lower part of the Wise Formation in southwestern Virginia; the New River Formation and the lower part of the Kanawha Formation in West Virginia; the lower part of the Breathitt Group—Bottom Creek Formation, Sewanee Sandstone, Alvy Creek Formation, Bee Rock Sandstone, and Grundy Formation—in eastern and southeastern Kentucky; and the uppermost part of the Gizzard Group, Crab Orchard Mountains Group, and Crooked Fork Group, and the lowermost part of the Slatestone Formation in Tennessee (fig. 1). In Alabama, Lower Pennsylvanian strata are subdivided into the Lower and Upper Pottsville Forma tions (fig. 1). Lower Pennsylvanian strata of Alabama and Tennessee reach maximum thicknesses of 5,700 ft and 2,500 ft, respectively (Luther, 1959; Pashin and Raymond, 2005). In the northern and westernmost areas of the bituminous coal fields of the northern Appalachian basin coal region (fig. 2), most Lower Pennsylvanian strata, particularly those parts equivalent to the Pocahontas Formation, appear to have never been deposited. Sediments of this age do exist, however, in parts of the Southern, Western Middle, and Eastern Middle fields in the Pennsylvania Anthracite region of eastern Penn sylvania, and in southeastern Ohio, West Virginia, Maryland, and the Broad Top field in Pennsylvania. In the Pennsylvania Anthracite region, the MississippianPennsylvanian boundary is gradational as mostly red, finegrained clastics of the Upper Mississippian Mauch Chunk Formation intertongue with and grade upward into gray, conglomeratic, clastic sediments typical of the Pennsylvanian Pottsville Formation (Wood and others, 1986; Edmunds, 1996; Brezinski, 1999). Lower Pennsylvanian Pottsville strata in the northern Appalachian basin coal region reach a maximum thickness of about 1,500 ft in the Southern field of the Penn sylvania Anthracite region (Wood and others, 1986). In Ohio, Pennsylvania, and Maryland, the separation between Lower and Middle Pennsylvanian rocks is problem atic because of the time-transgressive nature of the Pennsylva nian sediments deposited on the eroded Mississippian surface. For instance, traditionally the “Sharon” coal of Ohio and Pennsylvania is considered the first coal above the Mississip pian-Pennsylvanian boundary (fig. 1). In Ohio, the “Sharon”
Chapter D.2 Correlation Chart of Pennsylvanian Rocks in the Appalachian Basin 5 occurs in two widely separated areas: northeastern Ohio, in the vicinity of Sharon, Pa. (type section), and southern Ohio, near the city of Jackson (fig. 2). Although these deposits have long been assumed to be synchronous, palynological and lithostrati graphic data indicate otherwise (Bebel, 1982; Kosanke, 1984; C.F. Eble, Kentucky Geological Survey, written commun., 1999; Eble, 2002). These workers conclude that the “type” Sharon can best be correlated with lower Middle Pennsylva nian coal beds or coal zones (for example, the Pond Creek to Upper Elkhorn No. 3 interval in eastern Kentucky). Yet the “Sharon” at Jackson, Ohio, is more likely equivalent to a Lower Pennsylvanian coal, perhaps the Fire Creek or Beckley coal zones in the New River Formation of West Virginia. A similar diachronous relationship between the “type” Quaker town coal bed of northeastern Ohio and western Pennsylvania and the southern Ohio coal identified as “Quakertown” is suggested as well (Eble, 2002). Until definitive ages can be determined, ages of and correlations between coal beds in this part of the Pennsylvanian section are tentative (Slucher and Rice, 1994). Middle Pennsylvanian Rocks Middle Pennsylvanian strata are present in the northern, central, and southern Appalachian basin coal regions. As mentioned earlier, defining the exact base of the Middle Penn sylvanian in parts of Ohio, Pennsylvania, and West Virginia is problematic. Middle Pennsylvanian rocks are only partially preserved in the Black Warrior basin in Alabama and in the Wartburg basin in Tennessee (fig. 3). In southwestern Virginia, southeastern Kentucky, and northeastern Tennessee, southeast of the Pine Mountain thrust fault, post-Pennsylvanian erosion has removed all of the middle and upper Middle Pennsylva nian (Desmoinesian) rocks. Only lower Middle Pennsylvanian (Atokan) rocks remain (see figure 1). Typically, Middle Pennsylvanian rocks consist mostly of coal-bearing sequences of carbonaceous shale, mudstone, and siltstone with minor sandstone (Arndt, 1979). The rocks were deposited in coastal and deltaic systems and, unlike Lower Pennsylvanian rocks, commonly contain intervals of marine carbonate or shale (see figure 1). These marine intervals, par ticularly those in the lower Middle Pennsylvanian of eastern and southeastern Kentucky, southwestern Virginia, and West Virginia, consist mainly of coarsening-upward shale sequences tens of feet thick (Rice and others, 1994b). Conversely, marine units in all but the lowest Pennsylvanian intervals in Kentucky, Ohio, Pennsylvania, and Maryland, are typically thin (about 3 ft thick) and in many areas are cherty (Slucher and Rice, 1994). Commonly, marine units of the upper Middle Penn sylvanian in the northern Appalachian basin coal region are mostly thin shale and limestone intervals (see figure 1). Fresh water limestone beds first occur in the interval just above the Lower Kittanning coal bed (fig. 1) and generally occur in the seat rock of coals or in paleosol intervals, particularly in the overlying Conemaugh, Monongahela, and Dunkard Groups. Cecil (1990) attributed the development of these deposits to continental-drift-induced climatic shifts. Middle Pennsylvanian strata contain many valuable beds of coal, clay, and limestone. These rocks, which reach a maxi mum thickness of more than 2,000 ft in southwestern Virginia (Arndt, 1979; Englund and Thomas, 1991) include the Potts ville and Llewellyn Formations in east-central Pennsylvania, the upper part of the Pottsville Group, Allegheny Group or Formation (in West Virginia), and lowermost Conemaugh Group in western Pennsylvania, western Maryland, Ohio, and West Virginia; and the Wise and Harlan Formations in southwestern Virginia (fig. 1). Middle Pennsylvanian rocks in southeastern and eastern Kentucky and northeastern Tennes see include the middle and upper parts of the Breathitt Group (Pikeville, Hyden, Four Corners, and Princess Formations) and lowermost Conemaugh Formation. In east-central and southern Tennessee, Middle Pennsylvanian rocks include all but the lowest part of the Slatestone Formation, the Indian Bluff, Graves Gap, Redoak Mountain, Vowell Mountain, and Cross Mountain Formations (fig. 1). Upper Pennsylvanian Rocks Upper Pennsylvanian sediments include the Monongahela Group and all but the basal part of the Conemaugh Group in the northern Appalachian basin coal region, the upper part of the Llewellyn Group in the Pennsylvania Anthracite region, and the Conemaugh Formation in the central Appala chian basin coal region (fig. 1). Upper Pennsylvanian strata are absent in southwestern Virginia, southeastern Kentucky, all of Tennessee, and Alabama. The part of the Conemaugh Group included in the Upper Pennsylvanian is characterized by sequences of red and green mudstone, shale, siltstone and thin, non-economic coal beds. The lower part of the Upper Pennsylvanian, mainly the Ames Limestone and older (fig. 1), contains many thin marine limestone beds and shale intervals that are particularly widespread in western areas of the north ern Appalachian basin coal region. The lack of economic coal and overall abundance of “nonproductive” intervals of rocks within the group earned it the formerly applied name “Lower Barren Measures” (Wanless, 1939). In contrast, the overlying Monongahela Group consists mostly of sandstone, siltstone, shale, and mudstone with some limestone. The Monongahela Group, formerly known as the “Upper Productive Measures” (Wanless, 1939) contains several commercial coal beds, the most famous being the Pittsburgh coal bed (Tewalt and others, 2001). Upper Pennsylvanian strata within the Appalachian basin range in thickness from about 650 ft in Ohio (Collins, 1979) to as much as 1,300 ft in West Virginia (Arkle and others, 1979; Edmunds and others, 1979). Thicker strata, as much as 1,900 ft, are observed in the South ern anthracite field of Pennsylvania (Wood and others, 1969), which is located in the Valley and Ridge province.
6 Coal and Petroleum Resources in the Appalachian Basin References Cited Arkle, Thomas., Jr., 1959, Monongahela series, Pennsylvanian System, and Washington and Greene series, Permian Sys tem, of the Appalachian basin, Field trip 3 of Guidebook for field trips, Pittsburgh meeting, 1959: New York, Geological Society of America, p. 115–138. Arkle, Thomas, Jr., 1974, Stratigraphy of the Pennsylvanian and Permian Systems of the central Appalachians, in Briggs, Garrett, ed., Carboniferous of the Southeastern United States: Geological Society of America Special Paper 148, p. 5–29. Arkle, Thomas, Jr., Beissell, D.R., Larese, R.E., Nuhfer, E.B., Patchen, D.G., Smosna, R.A., Gillespie, W.H., Lund, Richard, Norton, Warren, Pfefferkorn, H.W., 1979, The Mississippian and Pennsylvanian (Carboniferous) Systems in the United States—West Virginia and Maryland: U.S. Geological Survey Professional Paper 1110–D, p. D1–D35. Arndt, H.H., 1979, Middle Pennsylvanian Series in the pro posed Pennsylvanian System stratotype, in Englund, K.J., Arndt, H.H., and Henry, T.W., eds., Proposed Pennsylvanian System stratotype, Virginia and West Virginia, Field Trip No. 1, Ninth International Congress of Carboniferous Stra tigraphy and Geology: AGI (American Geological Institute) Selected Guidebook Series No. 1, p. 73–80. Bebel, D.J., 1982, Depositional environments of the Lower Pottsville Group (Pennsylvanian) in Jackson County, Ohio: Athens, Ohio University, unpublished M.S. thesis, 102 p., 2 pls. in pocket. Berryhill, H.L., Jr., 1963, Geology and coal resources of Bel mont County, Ohio: U.S. Geological Survey Professional Paper 380, 113 p. Berryhill, H.L., Jr., and Swanson, V.E., 1962, Revised strati graphic nomenclature for Upper Pennsylvanian and Lower Permian rocks, Washington County, Pennsylvania: U.S. Geological Survey Professional Paper 450–C, p. C43–C46. Blake, B.M., 1992, Stratigraphy of the Lower and Middle Pennsylvanian Series in West Virginia, in Cecil, C.B., and Eble, C.F., eds., Paleoclimate controls on Carboniferous sedimentation and cyclic stratigraphy in the Appalachian basin: U.S. Geological Survey Open-File Report 92–546, p. 102–114. Blake, B.M., Jr., Cross, A.T., Eble, C.F., Gillespie, W.H., and Pfefferkorn, H.W., 2002, Selected plant megafossils from the Carboniferous of the Appalachian region, Eastern United States—Geographic and stratigraphic distribution, in Hills, L.V., Henderson, C.M., and Bamber, E.W., eds., Carboniferous and Permian of the World: Canadian Society of Petroleum Geologists Memoir 19, p. 259–335. Bownocker, J.A., and Dean, E.S. 1929, Analyses of the coals of Ohio: Ohio Division of Geological Survey Bulletin 34, 360 p. Bradley, W.H., 1956, Use of series subdivision of the Missis sippian and Pennsylvanian Systems in reports by members of the U.S. Geological Survey: American Association of Petroleum Geologists Bulletin, v. 40, no. 9, p. 2284–2285. Brezinski, D.K., 1999, Mississippian, in Shultz, C.H., ed., The geology of Pennsylvania: Pennsylvania Geological Survey Special Publication 1, p. 139–147. Carroll, R.E., 2004, Coal geology of Alabama, in 2004 Key stone coal industry manual: Prairieville, La., Mining Media, p. 450–455. Cecil, C.B., 1990, Paleoclimate controls on stratigraphic repetition of chemical and siliciclastic rocks: Geology, v. 18, no. 6, p. 533–536. Chesnut, D.R., Jr., 1992, Stratigraphic and structural frame work of the Carboniferous rocks of the central Appalachian basin in Kentucky: Kentucky Geological Survey, ser. 11, Bulletin 3, 42 p., 8 pls. in pocket. Chesnut, D.R., comp., 1997, Stratigraphy of the coal-bearing strata of the Eastern Kentucky coal field and adjacent States: Kentucky Geological Survey, database available at http://www.uky.edu/KGS/coal/coalcorrel.htm. (Data can be searched by district or geologic formation.) (Accessed October 12, 2006.) Chesnut, D.R., Jr., Andrews, W.M., Jr., Weisenfluh, G.A., Greb, S.F., Eble, Cortland, and Andrews, R.E., 2004, Coal geology of Kentucky, in 2004 Keystone coal industry manual: Prairieville, La., Mining Media, p. 506–522. Clendening, J.A., 1974, Palynological evidence for a Penn sylvanian age assignment of the Dunkard Group in the Appalachian basin; Part II: West Virginia Geological and Economic Survey Coal-Geology Bulletin 3, 107 p., 1 pl. in pocket. Clendening, J.A., 1975, Palynological evidence for a Penn sylvanian age assignment of the Dunkard Group in the Appalachian basin; Part I, in Barlow, J.A., ed., The age of the Dunkard—Proceedings of the First I.C. White Memorial Symposium, 1972: Morgantown, West Virginia Geological and Economic Survey, p. 195–221. Collins, H.R., 1979, The Mississippian and Pennsylvanian (Carboniferous) Systems in the United States—Ohio: U.S. Geological Survey Professional Paper 1110–E, p. E1–E26. Cross, A.T., 1954, The geology of the Pittsburgh coal [Appa lachian basin], Nova Scotia Department of Mines, Confer ence on the Origin and Constitution of Coal, 2d, June 1952, p. 32–111, with discussion [1952], reprinted: West Virginia Geological and Economic Survey Report of Investigations 10, p. 32–99.
Chapter D.2 Correlation Chart of Pennsylvanian Rocks in the Appalachian Basin 7 Darrah, W.C., 1969a, A critical review of the Upper Penn sylvanian floras of eastern United States with notes on the Mazon Creek flora of Illinois: Gettysburg, Pa., privately published, 220 p., 80 pls. Darrah, W.C., 1969b, The age of the highest coals of the Southern Anthracite field [abs.]: Pennsylvania Academy of Science Proceedings, v. 43, p. 14. Davis, M.W., and Ehrlich, Robert, 1974, Late Paleozoic crustal composition and dynamics in the Southeastern United States, in Briggs, Garrett, ed., Carboniferous of the Southeastern United States: Geological Society of America Special Paper 148, p. 171–185. Dodge, C.H., and Edmunds, W.E., 2004, Coal geology of Pennsylvania, in 2004 Keystone coal industry manual: Prairieville, La., Mining Media, p. 561–579. Donaldson, A.C., Renton, J.J., and Presley, M.W., 1985, Pennsyl vanian deposystems and paleoclimates of the Appalachians: International Journal of Coal Geology, v. 5, p. 167–193. Eble, C.F., 2002, Palynology of late Middle Pennsylvanian coal beds in the Appalachian basin: International Journal of Coal Geology, v. 50, p. 73–88. Eble, C.F., Greb, S.F., Martino, R.L. Lawson, Jeremy, and Tully, Lance, 2002, Middle and Upper Pennsylvanian stratigraphy, sedimentology, and coal geology in eastern Kentucky, in Ettensohn, F.R., and Smath, M.L., eds., Guide book for geology field trips in Kentucky and adjacent areas: Lexington, University of Kentucky, p. 74–107. Edmunds, W.E., 1988, The Pottsville Formation of the anthra cite region, in Inners, J.D., Bedrock and glacial geology of the North Branch Susquehanna Lowland and the Eastern Middle Anthracite field—Guidebook for the 53rd Annual Field Conference of Pennsylvania Geologists: Harrisburg, Pa., Pennsylvania Bureau of Topographic and Geologic Survey, p. 40–50. Edmunds, W.E., 1996, Correlation chart showing suggested revisions of uppermost Devonian through Permian stra tigraphy, Pennsylvania: Pennsylvania Geological Survey, 4th ser., Open-File Report 96–49, 8 p., 1 pl. Edmunds, W.E., Berg, T.M., Sevon, W.D., Piotrowski, R.C., Heyman, Louis, and Rickard, L.V., 1979, The Mississippian and Pennsylvanian (Carboniferous) Systems in the United States—Pennsylvania and New York: U.S. Geological Survey Professional Paper 1110–B, p. B1–B33. Edmunds, W.E., Skema, V.W., and Flint, N.K., 1999, Pennsyl vanian, in Shultz, C.H., ed., The geology of Pennsylvania: Pennsylvania Geological Survey Special Publication 1, p. 149–169. Eggleston, J.R., 1992, Stratigraphy and depositional environ ments, in Levine, J.R., and Eggleston, J.R., eds., Field trip guidebook; The anthracite basins of eastern Pennsylvania: U.S. Geological Survey Open-File Report 92–568, p. 4–8. Energy Information Administration, 2008, Coal production and number of mines by state and mine type, 2007–2006: Washington, D.C., Energy Information Administration table at http://www.eia.doe.gov/cneaf/coal/page/acr/table1.pdf. (Accessed October 12, 2006.) Englund, K.J., 1974, Sandstone distribution patterns in the Pocahontas Formation of southwest Virginia and southern West Virginia, in Briggs, Garrett, ed., Carboniferous of the Southeastern United States: Geological Society of America Special Paper 148, p. 31–45. Englund, K.J., 1979, The Mississippian and Pennsylvanian (Carboniferous) Systems in the United States—Virginia: U.S. Geological Survey Professional Paper 1110–C, p. C1–C21. Englund, K.J., and Thomas, R.E., 1991, Coal resources of Tazewell County, Virginia, 1980: U.S. Geological Survey Bulletin 1913, 17 p., 5 pls. in pocket. Englund, K.J., Lesure, F.G., Davies, W.E., King, E.R., and Perry, W.J., Jr., 1977, Mineral resource appraisal of the New River Gorge, Fayette, Raleigh, and Summers Counties, West Virginia: U.S. Geological Survey Open-File Report 77–207, 21 p. Englund, K.J., Arndt, H.H., and Henry, T.W., eds., 1979, Proposed Pennsylvanian System stratotype, Virginia and West Virginia, Ninth International Congress of Carbonifer ous Stratigraphy and Geology: AGI (American Geological Institute) Selected Guidebook Series No. 1, 138 p. Englund, K.J., Windolph, J.F., Jr., and Thomas, R.E., 1986, Origin of thick, low-sulphur coal in the Lower Pennsylva nian Pocahontas Formation, Virginia and West Virginia, in Lyons, P.C., and Rice, C.L., 1986, Paleoenvironmental and tectonic controls in coal-forming basins of the United States: Geological Society of America Special Paper 210, p. 49–61. Ferm, J.C., and Horne, J.C., comps., 1979, Carboniferous depositional environments in the Appalachian region: Columbia, S.C., University of South Carolina, Department of Geology, 760 p. Gradstein, F.M., Ogg, J.G., Smith, A.G., Bleeker, Wouter, and Lourens, L.J., 2004, A new geologic time scale, with special reference to Precambrian and Neogene: Episodes, v. 27, no. 2, p. 83–100. Greb, S.F., Chesnut, D.R., Jr., and Eble, C.F., 2004, Temporal changes in the coal-forming depositional sequences (Lower and Middle Pennsylvanian) of the central Appalachian basin, U.S.A., in Pashin, J.C., and Gastaldo, R., eds., Coalbearing strata—Sequence stratigraphy, paleoclimate, and
8 Coal and Petroleum Resources in the Appalachian Basin tectonics of coal-bearing strata: American Association of Petroleum Geologists Studies in Geology, v. 51, p. 89–120. Hatcher, R.D., Jr., Thomas, W.A., Geiser, P.A., Snoke, A.W., Mosher, Sharon, and Wiltschko, D.V., 1989, Alleghanian orogen, in Hatcher, R.D., Jr., Thomas, W.A., and Viele, G.W., eds., The Appalachian-Ouachita orogen in the United States, v. F–2 of The geology of North America: Boulder, Colo., Geological Society of America, p. 233–318. Havlena, Vaclav, 1975, Stratigraphic boundaries and problems in their selection, in Barlow, J.A., ed., The age of the Dunkard—Proceedings of the First I.C. White Memorial Symposium, 1972: Morgantown, West Virginia Geological and Economic Survey, p. 7–22. Heckel, P.H., Barrick, J.E., and Rosscoe, S.J., 2011, Conodontbased correlation of marine units in lower Conemaugh Group (Late Pennsylvanian) in northern Appalachian Basin: Stratigraphy, v. 8, no. 4, p. 253–269. Hennen, R.V., and Reger, D.B., 1913, Marion, Monongalia, Taylor County Report: West Virginia Geological Survey, 844 p. Hooker, A.V., 2004, Coal geology of Maryland, in 2004 Key stone coal industry manual: Prairieville, La., Mining Media, p. 524–525. Inners, J.D., 1988, The Eastern Middle Anthracite Field, in Inners, J.D., Bedrock and glacial geology of the North Branch Susquehanna Lowland and the Eastern Middle Anthracite field—Guidebook for the 53rd Annual Field Conference of Pennsylvania Geologists: Harrisburg, Pa., Pennsylvania Bureau of Topographic and Geologic Survey, p. 32–39. International Commission on Stratigraphy, Subcommission for Stratigraphic Information, 2009, GSSP table—All periods; Global boundary stratotype section and point (GSSP): International Commission on Stratigraphy, Subcommission for Stratigraphic Information Web site at http://stratigraphy. science.purdue.edu/gssp/index.php?parentid=all. (Accessed April 23, 2009.) Kosanke, R.M., 1984, Palynology of selected coal beds in the proposed Pennsylvanian System stratotype in West Virginia: U.S. Geological Survey Professional Paper 1318, 44 p. Lovett, J.A., 2004, Coal geology of Virginia, in 2004 Key stone coal industry manual: Prairieville, La., Mining Media, p. 600–605. Luther, E.T., 1959, The coal reserves of Tennessee: Tennessee Geological Survey Bulletin 63, 294 p. Martin, W.D., 1998, Geology of the Dunkard Group (Upper Pennsylvanian-Lower Permian) in Ohio, West Virginia, and Pennsylvania: Ohio Division of Geological Survey Bulletin 73, 49 p. McColloch, G.H., Jr., 2004, Coal geology of West Virginia, in 2004 Keystone coal industry manual: Prairieville, La., Mining Media, p. 613–623. McDowell, R.C., Grabowski, G.J., Jr., and Moore, S.L., 1981, Geologic map of Kentucky, 4 sheets, scale 1:250,000. Milici, R.C., 1974, Stratigraphy and depositional environ ments of Upper Mississippian and Lower Pennsylvanian rocks in the southern Cumberland Plateau of Tennessee, in Briggs, Garrett, ed., Carboniferous of the Southeastern United States: Geological Society of America Special Paper 148, p. 115–133. Nolde, J.E., 1996, Geology, natural gas, oil, and other mineral resources of Wise County, Virginia: Virginia Division of Mineral Resources Publication 144, 38 p. Pashin, J.C., 1999, Stratigraphy and structure of the Pottsville Formation in the Cahaba coalfield, in Pashin, J.C., and Carroll, R.E., comps., Geology of the Cahaba coalfield—A guidebook for the 36th Annual Field Trip of the Alabama Geological Society: Tuscaloosa, Alabama Geological Survey, p. 1–16. Pashin, J.C., 2004, Cyclothems of the Black Warrior basin, Alabama, U.S.A.—Eustatic snapshots of foreland basin tectonism, in Pashin, J.C., and Gastaldo, R.A., eds., Sequence stratigraphy, paleoclimate, and tectonics of coal-bearing strata: American Association of Petroleum Geologists Studies in Geology 51, p. 199–217. Pashin, J.C., and Raymond, D.E., 2005, Glacial-eustatic control of coalbed methane reservoir distribution (Pottsville Formation; Lower Pennsylvanian) in the Black Warrior basin of Alabama: Tuscaloosa, Ala., Geological Survey of Alabama [report], 15 p., 3 pls., available at http://portal.gsa. state.al.us/CO2/SECARB2/secarb2_files/0413%20Pashin. pdf. Patchen, D.G., Avary, K.L., and Erwin, R.B., coords., 1985, Correlation of stratigraphic units in North America, northern Appalachian region correlation chart: Tulsa, Okla., American Association of Petroleum Geologists, 1 sheet. Petersen, Carl, and Sparks, T.N., 2006, Geologic map of the Kentucky portion of the Pikeville 30 x 60 minute quadrangle, southeastern Kentucky: Kentucky Geological Survey, ser. 12, Geologic Map 11, scale 1:100,000. Phillips, T.L., and Peppers, R.A., 1984, Changing patterns of Pennsylvanian coal-swamp vegetation and implications of climatic control on coal occurrence: International Journal of Coal Geology, v. 3, p. 205–255. Rice, C.L., and Schwietering, J.F., 1988, Fluvial deposition in the central Appalachians during the Early Pennsylvanian: U.S. Geological Survey Bulletin 1839, p. B1–B10.
Chapter D.2 Correlation Chart of Pennsylvanian Rocks in the Appalachian Basin 9 Rice, C.L., Sable, E.G., Dever, G.R., Jr., and Kehn, T.M., 1979, The Mississippian and Pennsylvanian (Carboniferous) Systems in the United States—Kentucky: U.S. Geological Survey Professional Paper 1110–F, p. F1–F32. Rice, C.L., Hiett, J.K., and Koozmin, E.D., 1994a, Glossary of Pennsylvanian stratigraphic names, central Appalachian basin, in Rice, C.L., ed., Elements of Pennsylvanian stra tigraphy, central Appalachian basin: Geological Society of America Special Paper 294, p. 115–155. Rice, C.L., Kosanke, R.M., and Henry, T.W., 1994b, Revision of nomenclature and correlations of some Middle Pennsyl vanian units in the northwestern part of the Appalachian basin, Kentucky, Ohio, and West Virginia, in Rice, C.L., ed., Elements of Pennsylvanian stratigraphy, central Appala chian basin: Geological Society of America Special Paper 294, p. 7–26. Ruppert, L.F., and Rice, C.L., 2001, Chapter B—Coal resource assessment methodology and geology of the northern and central Appalachian basin coal regions, in Northern and Central Appalachian Basin Coal Regions Assessment Team, 2000 resource assessment of selected coal beds and zones in the northern and central Appalachian basin coal regions (ver. 1.0): U.S. Geological Survey Professional Paper 1625–C, p. B1–B2, on CD-ROM. (Version 1.01 is available at http://pubs.usgs.gov/pp/p1625c.) Ruppert, L.F., Tewalt, S.J., Bragg, L.J., Weisenfluh, G.A., Thacker, E.E., Blake, B.M., Jr., Sites, R.S., Freeman, P.A., Butler, D.T., and Bryant, L.C., 2001, Chapter G—A digital resource model of the Middle Pennsylvanian Pond Creek coal zone, Pottsville Group, central Appalachian basin coal region, in Northern and Central Appalachian Basin Coal Regions Assessment Team, 2000 resource assessment of selected coal beds and zones in the northern and central Appalachian Basin coal regions (ver. 1.0): U.S. Geological Survey Professional Paper 1625–C, p. G1–G88, on CD-ROM. (Version 1.01 is available at http://pubs.usgs.gov/pp/p1625c/.) Ryder, R.T., 1987, Oil and gas resources of the Black Warrior basin, Alabama and Mississippi: U.S. Geological Survey Open-File Report 87–450–X, 23 p. Siever, Raymond, and Potter, P.E., 1956, Sedimentary petrol ogy, [part] 2, Sources of basal Pennsylvanian sediments in the Eastern Interior basin: Journal of Geology, v. 64, no. 4, p. 317–335. Slucher, E.R., and Rice, C.L., 1994, Key rock units and distri bution of marine and brackish water strata in the Pottsville Group, northeastern Ohio, in Rice, C.L., ed., Elements of Pennsylvanian stratigraphy, central Appalachian basin: Geological Society of America Special Paper 294, p. 27–40. Sparks, T.N., 2004, Geologic map of the Middlesboro and parts of the Bristol 30 x 60 minute quadrangles, south eastern Kentucky: Kentucky Geological Survey, ser. 12, Geologic Map 7, 1 sheet. Sturgeon, M.T., Windle, D.L., Mapes, R.H., and Hoare, R.D., 1997, Pennsylvanian cephalopods of Ohio; Part 1, Nautiloid and bactritoid cephalopods: Ohio Division of Geological Survey Bulletin, v. 71, 191 p. Tewalt, S.J., Ruppert, L.F., Bragg, L.J., Carlton, R.W., Brezinski, D.K., Wallack, R.N., and Butler, D.T., 2001, Chapter C—A digital resource model of the Upper Pennsylvanian Pittsburgh coal bed, Monongahela Group, northern Appalachian basin coal region, in Northern and Central Appalachian Basin Coal Regions Assessment Team, 2000 resource assessment of selected coal beds and zones in the northern and central Appalachian basin coal regions (ver. 1.0): U.S. Geological Survey Professional Paper 1625–C, p. C1–C102, on CD-ROM. (Version 1.01 is available at http://pubs.usgs.gov/prof/p1625c/.) Thomas, W.A., 1988, The Black Warrior basin, in Sloss, L.L., ed., Sedimentary cover—North American craton, U.S., v. D–2 of The geology of North America: Boulder, Colo., Geo logical Society of America, p. 471–496. Tully, John, comp., 1996, Coal fields of the conterminous United States: U.S. Geological Survey Open-File Report 96–92, 1 sheet. (Available only at http://pubs.usgs.gov/ of/1996/of96-092/.) (Accessed October 12, 2006.) Wanless, H.R., 1939, Pennsylvanian correlations in the Eastern Interior and Appalachian coal fields: Geological Society of America Special Paper 17, 130 p., 9 pls. Wilkes, G.P., Bragg, L.J., Hostettler, K.K., Oman, C.L., and Coleman, S.L., 1992, Coal sample analyses from the southwest Virginia coalfield: Virginia Division of Mineral Resources Publication 122, 431 p. Wilson, C.W., Jr., Jewell, J.W., and Luther, E.T., 1956, Pennsylvanian geology of the Cumberland Plateau: Nash ville, Tennessee Department of Conservation, Division of Geology, Nashville, 21 p. Wood, G.H., Jr., Trexler, J.P., and Kehn, T.M., 1969, Geology of the west-central part of the southern anthracite field and adjoining areas, Pennsylvania: U.S. Geological Survey Professional Paper 602, 150 p., 4 pls. in pocket. Wood, G.H., Jr., Kehn, T.M., and Eggleston, J.R., 1986, Depositional and structural history of the Pennsylvania Anthracite region, in Lyons, P.C., and Rice, C.L., eds., Paleoenvironmental and tectonic controls in coal-forming basins of the United States: Geological Society of America Special Paper 210, p. 31–47. Zurawski, R.P., and Miller, B.W., 2004, Coal geology of Tennessee, in 2004 Keystone coal industry manual: Prairieville, La., Mining Media, p. 580–584.