Review of Lignite Resources of Western Tennessee and 

the Jackson Purchase Area, Western Kentucky 

By Paul C. Hackley1, Peter D. Warwick1, Roger E. Thomas2, and Douglas J. Nichols3 

Open-File Report 2006-1078 


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, product, or firm names is for descriptive purposes only, and does not imply endorsement by the U.S. 

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1

U.S. Geological Survey, MS 956 National Center, Reston VA 20192 
 2

Deceased, U.S. Geological Survey, Reston VA 20192 
 3

U.S. Geological Survey, MS 939 Denver Federal Center, Denver, CO 80225 


U.S. Department of the Interior 

U.S. Geological Survey 
U.S. Department of the Interior 

Gale A. Norton, Secretary 

U.S. Geological Survey 

P. Patrick Leahy, Acting Director 

U.S. Geological Survey, Reston, Virginia 2006 

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Tennessee and the Jackson Purchase Area, western Kentucky: U.S. Geological Survey Open-File Report 


2006-1078, 34 p., http://www.pubs.usgs.gov/of/2006/1078. 


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ii 
Contents 

Introduction .........................................................................................................................................................................1


Jackson Purchase Area, Western Kentucky ................................................................................................................1


Kentucky Lignite Deposits: Stratigraphic Occurrence ................................................................................................2


Kentucky Lignite Mineability ............................................................................................................................................4


Original Resources.............................................................................................................................................................4


Western Tennessee...........................................................................................................................................................4


Tennessee Lignite Deposits: Stratigraphic Occurrence.............................................................................................5


Coal Quality..........................................................................................................................................................................7


Organic Petrography..........................................................................................................................................................9


Coalbed Methane ...............................................................................................................................................................9


Conclusions .........................................................................................................................................................................9


Acknowledgements ...........................................................................................................................................................9


References...........................................................................................................................................................................9


Figures 

Figure 1. Map showing Coastal Plain deposits of the Mississippi Embayment..............................................................13


Figure 2. Generalized map of the Jackson Purchase area, western Kentucky................................................................14


Figure 3. Generalized stratigraphic column of the Jackson Purchase area, western Kentucky .....................................15


Figure 4. Map of the Jackson Purchase area, western Kentucky, showing outcrop distribution...................................16


Figure 5. Lignite bed in highwall of Kentucky-Tennessee Clay Company Sims open-pit clay mine...............................17


Figure 6. Lignite isopach map of part of the Sims mine, Kentucky-Tennessee Clay Company ......................................18


Figure 7. Map of western Tennessee showing outcrop distribution ...............................................................................19


Figure 8. Upper Cretaceous to Holocene stratigraphic column for western Tennessee.................................................20


Figure 9. Lignite bed in highwall of Spinks Clay Company Swaim open-pit clay mine ..................................................21


Figure 10. Gross calorific values of western Kentucky and Tennessee lignites .............................................................22


Figure 11. Ash yield of western Kentucky and Tennessee lignites .................................................................................23


Figure 12. Sulfur content of western Kentucky and Tennessee lignites .........................................................................24


Figure 13. HAPs (As-Hg) concentrations in western Kentucky and Tennessee lignite samples.....................................25


Figure 14. HAPs (Mn-U) concentrations in western Kentucky and Tennessee lignite samples .....................................26


Figure 15. Photomicrographs of western Kentucky and Tennessee lignite samples ......................................................27


Figure 16. Blue light photomicrographs of western Kentucky and Tennessee lignite samples .....................................28


Tables 

Table 1. Proximate and ultimate analytical data (as-received basis) for western Kentucky and Tennessee lignites ...29


Table 2. Proximate and ultimate analytical data (dry basis) for western Kentucky and Tennessee lignite samples ....30


Table 3. Major element analytical data for western Kentucky and Tennessee lignites.................................................31


Table 4. Trace element analytical data for western Kentucky and Tennessee lignites..................................................32


Appendix: Palynologic Data ..........................................................................................................................................33


iii 
Review of Lignite Resources of Western Tennessee 

and the Jackson Purchase Area, Western Kentucky 

By Paul C. Hackley, Peter D. Warwick, Roger E. Thomas, and Douglas J. Nichols 

Introduction 

This review of the lignite deposits of western 

Tennessee and the Jackson Purchase area in 

western Kentucky (Fig. 1) is a preliminary report on 

part of the U.S. Geological Survey’s National Coal 

Resource Assessment of the Gulf Coastal Plain 

Coal Province. Lignite deposits of western 

Kentucky and Tennessee are an extension of the 

Gulf Coastal Plain Coal Province (Cushing and 

others, 1964), and currently are not economic to 

mine. These deposits have not been extensively 

investigated or developed as an energy resource. 

This review includes a description of the geology 

of the lignite-bearing units, a discussion of the 

available coal quality data, and information on 

organic petrology. Palynological data for lignite 

samples collected in Kentucky and Tennessee as 

part of this work are presented in an Appendix. 

Jackson Purchase Area, Western Kentucky 

The Jackson Purchase area in western 

Kentucky includes the northernmost part of the 

Mississippi Embayment of the Gulf Coastal Plain, a 

trough of Cretaceous through Quaternary 

sedimentary strata that plunge gently southward 

along an axis that generally follows the 

Mississippi River (Fig. 1) (Cushing and others, 

1964). The sedimentary strata of the Jackson 

Purchase area are, in general, flat-lying or gently 

dipping westward toward the embayment axis. 

The Jackson Purchase area is situated between 

the Tennessee River to the east, the Ohio River to 

the north, and the Mississippi River to the west 

and the Kentucky-Tennessee State line to the 

south (Fig. 2). Lignite-bearing counties of the 

Jackson Purchase area include Ballard, Carlisle, 

Calloway, Fulton, Graves, Hickman, Marshall and 

McCracken Counties and the area covers about six 

percent (2,356 mi2) of the State. In general, the 

physiography consists of relatively flat-lying 

ground, with numerous lakes, ponds, sloughs, and 

swamps. Local relief generally is less than 100 

feet, and the lowest spot in Kentucky, at 260 feet 

above sea level, is found in the Jackson Purchase 

area (Kentucky Geological Survey, 2000). Much of 

the bedrock in western Kentucky was extensively 

eroded and covered by alluvial deposits from the 

major rivers within the northern Mississippi 

Embayment during the Late Tertiary. Alluvial 

deposits predominantly consist of sand, silt, clay, 

and gravel materials. Bedrock remnants include 

Upper Paleozoic limestone exposed in the eastern 

part of the area and Upper Cretaceous and Lower 

Tertiary clastic rocks exposed throughout the 

Purchase area. 

The Jackson Purchase area is an important 

resource of several industrial minerals including 

silica sand, ceramic clay, and ball clay (Anderson, 

2000). Clay is a particularly important constituent 

of the bedrock stratigraphy of the Purchase area 

and historically has been mined extensively 

(Gildersleeve, 1945; Olive and Finch, 1969). 

Currently, Kentucky is the second largest producer 

of ball clay in the United States (Anderson, 2000). 

Ball clays are associated with the Lower Tertiary 

strata and are used in the United States, Canada, 

and Mexico for ceramic production (Deems and 

Vincent, 1997). Kentucky also is one of the 

1
Nation’s leading bituminous coal production states 

with a history of coal mining extending back into 

the mid-1700s (Energy Information Administration, 

1999a). Bituminous coal is produced from two 

major coal fields elsewhere in the State with an 

annual output averaging over 160 million short 

tons (Energy Information Administration, 1999a). 

Thin, discontinuous lignite beds occur in the Upper 

Cretaceous and Lower Tertiary strata of the 

Jackson Purchase area (Olive and McDowell, 

1986). 

Kentucky Lignite Deposits: Stratigraphic 

Occurrence 

A generalized stratigraphic column showing 

reported lignite occurrences in the Purchase area 

is shown in Figure 3. Lignite lenses primarily are 

found in the Tertiary Wilcox Formation, Claiborne 

Group, and Jackson Formation and, less frequently, 

in the Upper Cretaceous McNairy Formation. 

The lignite beds in the Upper Cretaceous 

McNairy Formation (Stephenson, 1914) have been 

attributed to marine to freshwater deltaic 

deposition. The McNairy primarily is comprised of 

light to dark-gray, fine to medium, unconsolidated 

sand that weathers to yellow or reddish brown 

(Olive, 1980). Where the McNairy Formation is 

exposed in the eastern part of the Jackson 

Purchase area (Fig. 2) it is reported to be 300 to 

350 feet thick and disconformable over Paleozoic 

rocks along the banks of the Kentucky Lake and its 

tributaries (Olive, 1980). Sands of the McNairy are 

interbedded with gray, black, or brown clays with 

minor chert gravels and silts and lignite (Olive, 

1980; Olive and McDowell, 1986). These 

sediments were deposited in a warm temperate to 

subtropical climate as indicated by pollen studies 

(Tschudy, 1970). The McNairy is described as 

predominantly sand in the southern part of the 

Purchase area and increasingly clay-rich northward 

to near Paducah (Fig. 2) where it is primarily clay 

(Olive and McDowell, 1986). In general, lignite 

deposits are associated with or overlie the clay 

interbeds and are not laterally extensive. Lignite 

in the McNairy Formation reportedly is exposed in 

a bed one and a half feet thick in northeastern 

Calloway County (Olive, 1980) and is present in the 

subsurface in the Paducah area, McCracken 

County (Hower and others, 1990). Lignite lenses in 

McNairy Formation sands as much as six in thick 

were observed in the clay pits of various mining 

companies in the area (Roberts, 1945). In addition 

to discrete lignite beds, lignitic clays are widely 

reported from the McNairy (Roberts, 1945; Pryor, 

1960; Olive, 1966, 1969, 1980). Petrographic 

examination of a lignite sample from the McNairy 

Formation suggests an origin from transported or 

allochthonous organic material based on abundant 

inertodetrinite and huminodetrinite content (Hower 

and others, 1990). 

Sediments of the Early Eocene Wilcox 

Formation consist primarily of clayey sands with 

interbedded clay and silt (Olive, 1980; Olive and 

McDowell, 1986) deposited in a freshwater 

environment (Olive, 1980). The sand is described 

as light gray and pale brown to yellowish gray and 

weathers yellowish orange to reddish brown and 

pinkish gray (Olive, 1980). Whitlatch (1940) 

referred to Wilcox sands as “sawdust sand” due to 

the amount of included kaolinite, which produces 

the sawdust texture. The formation ranges from 

zero to 200 feet in thickness and disconformably 

overlies the Paleocene Porters Creek Clay of the 

underlying Midway Group (Olive, 1980) (Fig. 3). 

Lignite is found as a discrete lens as much as three 

feet thick in northeastern Calloway County (Fig. 2) 

and lignitized plant material and leaf imprints are 

found in Wilcox sand and clay in many places 

(Olive, 1980). Whereas the Wilcox Group is an 

important lignite-bearing unit in the Gulf coastal 

regions of Texas, Louisiana, and Arkansas 

(Mukhopadhyay, 1989), deposits of Wilcox lignite 

are relatively rare in western Kentucky (Hower and 

others, 1990). The name Holly Springs Formation 

(Lowe, 1914) previously was used for the lower 

part of the Wilcox Formation in western Kentucky 

and it is this portion of the Wilcox that has 

supported many of the historic ball clay mining 

2
operations in western Kentucky (Gildersleeve, 

1945). 

Overlying the Wilcox in western Kentucky is 

the Claiborne Group (Fig. 3), a thick sequence 

composed primarily of sand with interbedded 

lenses of clayey silt, silty clay, and lignite (Olive, 

1980). Most lignite occurrences described in this 

report are from the Claiborne. The Claiborne 

Group is reported to be disconformable over the 

Wilcox and as much as 600 feet thick in the 

subsurface near the embayment axis at the 

Kentucky-Tennessee state line (Olive, 1980). The 

USGS recognizes the Claiborne Group in western 

Kentucky as consisting of, in ascending order; the 

Tallahatta Formation, the Sparta Sand, the Cook 

Mountain Formation, and the Cockfield Formation 

(Hosman, 1996). The Claiborne dominantly is 

composed of white, light gray, and pale to medium 

brown sand, weathering yellowish orange to 

reddish brown and pinkish gray with common 

cross-bedding and cut-and-fill structures (Olive, 

1980). Lignite primarily occurs in the east-central 

and western parts of the Claiborne outcrop belt 

(Fig. 4) where typically it is found in beds less than 

five feet thick (Olive, 1980). Lignite is reported to 

be brownish black to black in color, structureless 

to shaly, and locally composed of woody fragments 

consisting of tree trunks and stumps (Olive, 1980). 

Olive and Finch (1969) described a lignite bed 

approximately two and a half feet thick associated 

with clays of the Claiborne in Ballard County (Fig. 

4). Olive (1971) described as many as three lignite 

beds in the Claiborne ranging in thickness from a 

few inches to several feet in the vicinity of 

Blandville, Ballard County (Fig. 2) and presented 

proximate/ultimate analytical data for two 

samples. Based on significant changes in peat 

thickness, flora, and geochemistry over short 

distances, it is likely that Claiborne lignites in 

western Kentucky developed in oxbow lake 

sedimentary environments (Potter and Dilcher, 

1980; Hower and others, 1990). Lignite samples 

from fresh exposures of Claiborne sediments in 

Carlisle and Graves Counties have been studied in 

detail (Hower and others, 1981; 1982; 1990). 

Lignite usually is found associated with Claiborne 

clay lenses that typically are narrow, elongated, 

and curved in shape, surrounded on the bottom 

and sides by cross-bedded sands, suggesting that 

they are old meandering stream channels that 

were ultimately cut off and filled by sediments as 

oxbow lakes (Potter and Dilcher, 1980). Potter and 

Dilcher (1980) estimated that the clay and lignite 

deposits formed over periods ranging from 500 to 

1,500 years. The meandering of streams across 

the embayment axis and temporal formation of 

oxbow lakes as sites for lignite formation resulted 

in the current geographic isolation of individual 

lignite deposits and their discontinuous nature 

(Potter and Dilcher, 1980). Hower and others 

(1990) reported that Claiborne lignites are distinct 

in their general lack of inertinite macerals and in 

the presence of a diverse, angiosperm-dominated 

flora. 

Overlying the Claiborne Group in western 

Kentucky is the Jackson Formation, named for 

exposures near Jackson, Mississippi (Figs. 1 and 3) 

(Hilgard, 1860). Sediments of the Jackson 

Formation consist of two primary units; a fine 

facies composed primarily of silty clay and clayey 

silt with interbedded sands and a coarse facies 

composed of sand (Olive, 1980). The Jackson is 

not divisible from the Claiborne Group as a map 

unit in western Kentucky owing to similarities in 

lithologic composition and appearance. A 

generalized boundary based on palynological 

(Olive, 1980) data is shown on Figure 4 (Warwick 

and others, 1997). A petrographic distinction is 

made between Jackson Formation and Claiborne 

Group sands in that the Jackson Formation is 

reported to contain chert, which is absent in the 

underlying Claiborne (Hower and others, 1990). 

The contact relation between the Jackson 

Formation and underlying Claiborne strata is 

uncertain and is described as gradational (Olive 

and Finch, 1969), disconformable (Olive, 1980), or 

conformable (Olive, 1980). The Jackson Formation 

is estimated to be approximately 400 feet in 

3
thickness (Olive, 1972). Lignitized plant material 

and leaf imprints are found in the silt and clay 

layers of the fine facies of the Jackson Formation 

(Olive, 1980). Three lignite samples collected from 

the Jackson Formation at the Sims clay mine of the 

Kentucky-Tennessee Clay Company (Fig. 4) were 

analyzed for proximate/ultimate data and major 

and trace element concentrations (Tables 1-4). 

Figure 5 is a photograph from the Sims mine 

showing the sampled lignite bed. The lignite 

samples collected from this bed are relatively 

dense and massive, dull brown to dark gray, and 

contain thin clay interlayers. Little to no woody 

material was observed in the lignite bed and no 

clear rooting was observed in the underclay. 

Palynological observations of these samples 

indicate a middle Eocene age (see Appendix). A 

substantial body of work on the Tertiary 

paleobotany of western Kentucky and Tennessee 

has been presented by David Dilcher of Indiana 

University (now at the Florida Museum of Natural 

History) and his students and colleagues (e.g., Sun 

and Dilcher, 1989; Herendeen and Dilcher, 1986, 

1987; Mickle and Dilcher, 1987). 

Quaternary deposits cover the lignite-bearing 

Eocene and Cretaceous lithologies of the Jackson 

Purchase area. These deposits consist of Pliocene 

and Pleistocene fluvial terraces, Pleistocene 

glacial deposits and loess and alluvium of 

Pleistocene and Holocene age underlying the flood 

plains of modern streams (Olive and Finch, 1969; 

Olive and McDowell, 1986). Fluvial deposits of 

Pliocene and Pleistocene age consist of 

continental gravels that blanket the underlying 

Eocene sediments and thin from approximately 100 

feet in the southeastern part of the Purchase area 

to about 30 feet along the Ohio River (Olive and 

Finch, 1969). Loess, consisting of wind-deposited 

silt, reaches a maximum thickness of about 80 feet 

bordering the Mississippi River along the western 

part of the Purchase area and thins to about ten 

feet in the eastern part of the area (Olive and 

Finch, 1969). The thickness of over-lying 

Holocene-Pleistocene alluvium can be as much as 

200 feet, particularly in the major river valleys 

(Olive, 1980). 

Kentucky Lignite Mineability 

Lignite has not been historically mined in 

western Kentucky and relatively little data exist 

characterizing the thickness of overburden and/or 

contiguity of lignite beds. Lignite and lignitic clays 

interbedded with commercial clay deposits in the 

Wilcox Formation historically have been 

considered overburden and discarded as mine 

waste (Gildersleeve, 1945). Data provided by the 

Kentucky-Tennessee Clay Company for the Sims 

mine in Carlisle County (L. G. Kirk, written 

communication, 1994) indicate that a Jackson 

lignite bed (sampled for this work and discussed in 

text) ranges from zero to eight and a half feet in 

thickness (Fig. 6) and is covered by 19 to 50 feet of 

overburden. On average, overburden is 

approximately 32.8 feet thick. The lignite bed 

averages six feet in thickness and was 

encountered in 51 borings spaced over an area 

less than 0.07 mi2. The lignite deposit is broadly 

linear in shape, pinches out toward the east, 

trends north-south, and thickens in a curvilinear 

pattern (Fig.6), suggesting deposition in an 

abandoned channel environment. 

Original Resources 

No estimates of original lignite resources have 

been made for western Kentucky. Olive (1971) 

reported that lignite reserves probably are less 

than 50,000 short tons in reference to as many as 

three lignite beds in the Claiborne Formation near 

Blandville in Ballard County. 

Western Tennessee 

Lignite has not been developed in western 

Tennessee as an energy resource though several 

energy companies conducted extensive exploration 

programs for lignite resources in the late 1970s 

(Parks, 1981). The lignite-bearing units of western 

Tennessee are, as in western Kentucky, part of the 

Mississippi Embayment sequence of Cretaceous 

4
through Quaternary sediments and sedimentary 

strata (Fig. 1) (Cushing and others, 1964). The 

Mississippi Embayment units of western 

Tennessee are, in general, flat-lying or gently 

dipping westward towards the embayment axis. 

Thin, discontinuous lignite beds occur in the 

Upper Cretaceous and Lower Tertiary Gulf Coastal 

Plain sediments of western Tennessee (Russell 

and Parks, 1975). However, despite extensive 

investigation (Parks, 1981), the lignite deposits of 

western Tennessee currently are not economically 

feasible to mine and have not been developed as 

an energy resource. The lignite-bearing units crop 

out along a linear belt extending northnortheastward across the State primarily in 

Fayette, Hardeman, McNairy, Chester, Henderson, 

Madison, Haywood, Carroll, Weakly, and Henry 

Counties (Fig. 7). In all cases, lignite beds are 

described as laterally discontinuous lenses that 

constitute volumetrically minor components of the 

geologic units (Russell and Parks, 1975). However, 

exploration programs and appraisal of hydrologic 

conditions in anticipation of lignite mining in 

western Tennessee demonstrated that tremendous 

(1.0 billion short tons) lignite reserves are present 

(Luppens, 1978; Parks, 1981). 

In the Upper Cretaceous McNairy Formation 

(Hardeman and others, 1966), lignitic clays occur in 

association with mined or previously mined ball 

clay deposits (Nelson, 1912; Russell and Parks, 

1975) and primarily are known from Henry County 

(Fig. 7) (Parks, 1981). Lignite deposits in the 

overlying Paleocene-Eocene Wilcox Group are 

thought to be the most abundant in the southern 

part of western Tennessee in Hardeman County 

(Parks, 1981). The Eocene Claiborne Group and 

Jackson Formation also host lignites deposits in 

western Tennessee (Parks, 1981). Estimates of 

lignite reserves for western Tennessee indicate 

that approximately 1 billion short tons of lignite 

occur in the Claiborne and Wilcox Group units in 

beds that are two to nine feet thick (Luppens, 

1978). A proposal outlining data needed in 

anticipation of strip-mining of lignite resources in 

western Tennessee was presented by the U.S. 

Geological Survey and the Tennessee Division of 

Geology (Parks, 1981), but further evaluation of 

lignite resources was not completed and lignite 

mining has not commenced. 

Tennessee Lignite Deposits: Stratigraphic 

Occurrence 

Lignite beds are found in several stratigraphic 

horizons within the Cretaceous McNairy 

Formation, the Paleocene Midway Group, the 

Paleocene-Eocene Wilcox Group, and in the 

Eocene Claiborne Group and Jackson Formation of 

western Tennessee. These strata are lateral 

equivalents of the units described above for 

western Kentucky but are, in the case of the 

Wilcox, raised to Group stature in Tennessee as 

better exposure over a greater area permits more 

detailed mapping and subdivision of the geologic 

units. A generalized stratigraphic column for 

Upper Cretaceous and Tertiary strata in western 

Tennessee is presented in Figure 8. 

The Upper Cretaceous McNairy Formation was 

named for exposures near Cypress in McNairy 

County (Fig. 7) (Russell, 1966) and is comprised of 

non-marine and nearshore marine sands. The unit 

is described as comprised of three facies: a very 

fine-grained nearshore basal sand, an overlying 

coarser sand of fluvial, deltaic, and estuarine 

origin, and an upper transgressive marine sand 

(Russell and Parks, 1975). The middle facies 

contains discontinuous, thin-bedded, lenticular 

clay bodies consisting of light brown to light gray 

to white, kaolinite-dominated plastic clays and 

lignitic clays with fossilized plant fragments 

(Russell and Parks, 1975). The McNairy Formation 

ranges from approximately 290 to 500 feet thick in 

southern Tennessee, dipping gently to the west, 

and extends entirely across the state, cropping out 

in a belt approximately 15 miles wide in the south 

and narrowing to about six miles wide in the north 

(Nelson, 1911; Russell and Parks, 1975). 

5
The Paleocene Midway Group in western 

Tennessee (Fig. 8) includes, in ascending 

stratigraphic order, the Clayton Formation and the 

Porters Creek Clay (Roberts, 1928; Hosman, 1996). 

The Clayton Formation crops out in Hardeman and 

McNairy Counties in southwestern Tennessee, 

where it disconformably overlies the McNairy 

Formation and is estimated to average 80 feet in 

thickness (Russell and Parks, 1975). Lignitic clays 

locally are found in the Clayton Formation and rare 

lenses of impure lignite are found associated with 

clays (Russell and Parks, 1975). The conformably 

overlying Porters Creek Clay is a distinctive body of 

offshore marine clay and minor sand ranging from 

100 to 150 feet thick. At some localities in the 

upper part of the Porters Creek, disseminated 

particles of lignitic material occur in lenses of 

black silty clay (Russell and Parks, 1975). 

The Paleocene-Eocene Wilcox Group (Roberts 

and Collins, 1926) disconformably overlies the 

Porters Creek Clay in western Tennessee and 

includes, in ascending stratigraphic order, the Old 

Breastworks Formation, the Fort Pillow Sand, and 

the Flour Island Formation (Parks and Carmichael, 

1990a, 1990b; Hosman, 1996). Collectively, these 

units range from zero to 200 feet thick and crop out 

in a north-northeast trending belt across western 

Tennessee, narrowing northward from 

approximately 13 miles wide in Hardeman County 

to less than one mile wide in Henry County (Fig. 7). 

Lignite is present as thin lenses associated with 

lignitic clays or carbonaceous clay and silt in the 

Old Breastworks and Flour Island Formations (Parks 

and Carmichael, 1990a, 1990b). The lignite 

deposits are described as brownish black to 

moderate brown and containing variable amounts 

of clay and silt (Russell and Parks, 1975). Beds 

range from inches to several feet in thickness but 

rarely exceed one foot (Russell and Parks, 1975). 

As in western Kentucky, “sawdust sand” is 

described as a distinctive feature of Wilcox Group 

sediments in western Tennessee (Russell and 

Parks, 1975). 

The Claiborne Group in western Tennessee 

includes, in ascending stratigraphic order, the 

Memphis Sand, the Cook Mountain Formation, and 

the Cockfield Formation (Fig. 8). As in western 

Kentucky, the Claiborne is the dominant lignitebearing unit of western Tennessee and was the 

source of the lignite samples collected and 

analyzed by the USGS as part of this work. 

Moreover, the important ball clay mining 

operations of western Tennessee dominantly are 

developed in Claiborne units or equivalents 

(Nelson, 1911). Clays of the Claiborne contain an 

abundant terrestrial fossil flora indicating 

deposition predominantly in nonmarine 

environments (Russell and Parks, 1975; Clark, 

1977). The basal unit of the Claiborne, the 

Memphis Sand, disconformably overlies the Flour 

Island Formation of the Wilcox Group and consists 

of a thick body of sand with subordinate lenses of 

clay and silt. The stratigraphic boundary between 

the uppermost units of the Wilcox and the 

overlying Memphis Sand is reported to be an 

erosional surface with local relief of 50 feet or 

more (Russell and Parks, 1975). The Memphis 

Sand ranges from zero to about 900 feet in 

thickness and, where the original thickness is 

preserved, generally is 400 feet thick or greater 

(Parks and Carmichael, 1990a). The unit in 

western Tennessee makes up a substantial part of 

the Memphis aquifer, an important groundwater 

resource in the area (Parks and Carmichael, 

1990a). Clay and silt lenses are reported to be 

carbonaceous and lignitic with thin lenses of 

lignite occurring locally (Parks and Carmichael, 

1990a). The Cook Mountain Formation consists 

primarily of clay, with lesser silt and sand and 

ranges from 40 to 200 feet in thickness (Parks and 

Carmichael, 1990a). The unit is conformable over 

the Memphis Sand and serves as an upper 

confining layer (Parks and Carmichael, 1990a), but 

lignite occurrences are not reported. Conformable 

over the Cook Mountain is the Cockfield Formation, 

another important aquifer unit in the regional 

groundwater supply (Parks and Carmichael, 1990b). 

6
The Cockfield Formation primarily is composed of 

sand with lesser silt, clay, and lignite. Where the 

original stratigraphy is preserved, the Cockfield 

ranges from 235 to 270 feet in thickness (Parks and 

Carmichael, 1990b). In places, the Cockfield has 

undergone extensive erosion and is highly variable 

in thickness, ranging from zero to 270 feet (Parks 

and Carmichael, 1990b). Lignite beds commonly 

are associated with clays and silts (Parks and 

Carmichael, 1990b). Three lignite samples were 

collected from the Cockfield in the Swaim pit of 

the Spinks Clay Company and analyzed for 

proximate/ultimate data (Table 1). The location of 

the collected samples is shown on Figure 7 and 

palynological data are presented in the Appendix. 

Figure 9 is a photograph from the Swaim pit 

showing the sampled lignite bed. The lignite 

samples collected from this bed are relatively clayrich and blocky, and contain woody bits and 

fragments. The lignite bed is elliptical and shows 

distinct lateral variations. Palynological 

observations of the lignite samples indicate a 

middle Eocene age (see Appendix). An additional 

four samples were collected from the Cockfield 

Formation in the Roberts pit of the Spinks Clay 

Company and analyzed for proximate/ultimate data 

(Table 1) and major and trace element 

concentrations (Tables 3 and 4). The location of 

the collected samples is shown on Figure 7 and 

palynological data are presented in the Appendix. 

The sampled lignite bed at the Roberts pit contains 

scattered woody material, becomes increasingly 

clay-rich upwards, before eventually grading into 

clay, and is dark yellowish brown (10 YR 4/4) to 

dusky yellowish brown (10 YR 2/2) in color. The 

underclay is well-rooted. 

The Cockfield Formation is overlain by the 

Upper Eocene Jackson Formation (Fig. 8), another 

lignite-bearing unit. Due to similarities in 

lithology, the Jackson and Cockfield Formations 

cannot be reliably subdivided and a rough estimate 

of the thickness of the Jackson Formation is given 

as zero to 150 feet by Parks and Carmichael 

(1990b). A similar situation exists in western 

Kentucky, as outlined above, where the Jackson 

and Claiborne are distinguished only by 

petrographic and palynological subtleties and 

cannot be reliably subdivided in the field. 

Coal Quality 

Coal quality data for western Tennessee and 

Kentucky lignite deposits are scarce and previously 

published material consists of proximate/ultimate 

and major element analytical data for eleven 

Claiborne Group lignites and one McNairy 

Formation lignite in western Kentucky (Hower and 

others, 1990). Proximate/ultimate analyses of two 

additional Kentucky Claiborne lignite samples 

were presented on a geologic quadrangle map 

(Olive, 1971). This report includes new 

proximate/ultimate, major- and trace-element 

analyses for three Jackson Formation lignite 

samples from western Kentucky (Sims pit) and four 

samples of Claiborne Group lignite from Tennessee 

(Roberts pit). An additional three Claiborne Group 

samples from Tennessee were analyzed only for 

proximate/ultimate data (Swaim pit). All of the 

available coal quality data for western Kentucky 

are presented in Tables 1-4 and the locations of 

samples are shown on Figure 4 and Figure 7. Coal 

quality data are discussed in comparison with 

average and maximum values of Gulf Coast 

lignites as published in the U.S. Geological Survey 

Coal Quality Database CD-ROM (USGS COALQUAL) 

(Bragg and others, 1998). The average and 

maximum values of Gulf Coast lignites as 

represented by the analyses contained in the 

USGS COALQUAL database incorporate all 

samples obtained from Upper Cretaceous through 

Tertiary strata in the Gulf Coast Basin and are not 

representative of a particular formation. 

Moisture content of the lignite samples 

analyzed as part of this work and from Olive (1971) 

ranges from 39.15 to 51.8 percent on an asreceived basis (Table 1), and averages 44.9 

percent, higher than the Gulf Coast average of 35.0 

percent. Moisture content data from Hower and 

others (1990) were presented on an as-determined 

7
basis for moisture content and indicate 11.16 

percent for the McNairy Formation sample and a 

range of 7.30 to 41.68 percent for Claiborne Group 

samples (not tabulated here). 

Claiborne and Jackson lignite samples from 

western Kentucky and Tennessee have gross 

calorific values that range from 5,397 to 6,616 

Btu/lb (Table 2) on a moist, mineral-matter-free 

(m,mmf) basis. The samples collected and 

analyzed as part of this work and by Olive (1971) 

have lower gross calorific values than the average 

of Gulf Coast lignites (7,495 Btu/lb, m,mmf basis) 

(Fig. 10). However, the data published by Hower 

and others (1990) indicate relatively higher gross 

calorific values for Eocene lignite samples from 

western Kentucky, including some samples of 

subbituminous rank. These samples may have 

been allowed to dry substantially prior to analysis 

and the gross calorific values presented by Hower 

and others (1990) have been omitted from Table 2 

and Figure 10. 

Reflectance measurements were performed 

for seven samples collected as part of this work 

following American Society for Testing and 

Materials (ASTM) D 2798-05 methods and 

procedures (ASTM, 2005a). Maximum reflectance 

values of ulminite B in immersion oil (Rmax) range 

from 0.23 to 0.29 (Table 2), in agreement with the 

rank classification calculated from the gross 

calorific value obtained by ASTM D 5865-04 

(ASTM, 2005b). 

Ash yield ranges from 11.8 to 45.48 percent on 

a dry basis (Table 2) for the samples analyzed as 

part of this work and by Olive (1971); ash yield in 

the sample set presented by Hower and others 

(1990) is over 50 percent for three samples. Note 

that samples 7462, 7464, 7465, and 7457 of their 

data set (Table 2) contain significantly elevated 

ash; these samples have been excluded from 

presentation in Figures 10-12. Furthermore, of the 

lignite samples collected as part of this work, 

samples PW-94-16, PW-94-18, PW-94-23, and PW94-30 have a higher ash yield than that permitted 

in the COALQUAL database (less than or equal to 

33 percent on an as-determined basis). These 

samples have been omitted from presentation in 

Figures 10-14. In general, ash yield of western 

Kentucky and Tennessee lignite samples is higher 

than the average of Gulf Coast lignites (19.8 

percent, dry basis); of the 16 samples presented in 

Figure 11, ten have higher ash yield than the 

average of Gulf Coast lignite samples. Samples 

collected in this study have sulfur contents ranging 

from 0.73 to 2.10 percent on a dry basis (Table 2), 

and, with the exception of the highest value, all 

values are below the Gulf Coast average (1.69 

percent, dry basis) (Fig. 12). The sulfur content of 

the previously published data for Claiborne 

samples ranges from 0.66 to 4.8 percent and is 

1.10 percent in the McNairy sample (Olive, 1971; 

Hower and others, 1990), similar to the Gulf Coast 

average. 

Of the ten samples collected by the U.S. 

Geological Survey from western Kentucky and 

Tennessee, seven were analyzed for major and 

trace element concentrations by inductively 

coupled plasma emission spectrometry (ICP-AES) 

and inductively coupled plasma mass spectrometry 

(ICP-MS) and the analytical results are presented 

in Tables 3 and 4. In addition, major element 

analytical data published by Hower and others 

(1990) are incorporated into Table 3. Of particular 

interest are concentrations of environmentally 

sensitive trace elements that have been identified 

as possible hazardous air pollutants (HAPs) in the 

United States Clean Air Act Amendments of 1990. 

The concentrations of the trace elements arsenic, 

beryllium, cadmium, cobalt, chromium, mercury, 

manganese, nickel, lead, antimony, selenium, and 

uranium are compared to average and maximum 

Gulf Coast lignite values on a whole-coal remnant 

moisture basis compiled from the USGS 

COALQUAL database (Bragg and others, 1998) in 

Figs. 13 and 14. Note that of the seven lignite 

samples analyzed, only those with ash yield lower 

than 30 weight percent are strictly comparable 

8
with those in the COALQUAL database. Therefore, 

only five samples are plotted in Figs. 13 and 14. 

Organic Petrography 

Claiborne and Jackson lignite samples from 

western Tennessee and Kentucky were prepared 

following the procedures outlined in Pontolillo and 

Stanton (1994), and qualitatively examined in 

incident white and blue light. All of the samples 

are semi-sapropelic in character; generally 

liptinite- and mineral-matter-rich, and poor in 

humic (woody) material, consistent with 

subaquatic formation in the oxbow lakes of 

abandoned river and stream channels (Potter and 

Dilcher, 1980). All samples are mostly devoid of 

inertinite macerals, with the exception of funginite 

(Figs. 15A-B), consistent with the petrographic 

descriptions reported by Hower and others (1990) 

for Claiborne lignites of the Jackson Purchase 

area. Trace quantities of the inertinite macerals 

inertodetrinite and fusinitized corpohuminite are 

present. Inertinite is qualitatively estimated to 

comprise <1 vol.% of the organic material for all 

Jackson and Claiborne samples examined. 

Huminite mostly consists of detrohuminite (Fig. 

15C), an aggregation of perhydrous organic 

detritus containing fragments of other types of 

huminite, mineral-matter, liptinite, and scarce 

inertinite. Some remnant humic plant tissues are 

present as textinite (Figs. 15D-F). Liptinite 

macerals include sporinite (Figs. 16A-B), resinite 

(Fig. 16C), suberinite (Figs. 16D-E), and alginite 

(Fig. 16F). The occurrence of alginite is consistent 

with a subaquatic facies for some of the Jackson 

and Claiborne lignite. 

Coalbed Methane 

Although the occurrence of biogenetic in-situ 

coal bed methane in western Tennessee and 

Kentucky lignites is unknown, deep basin Gulf 

Coast lignites may contain significant gas 

resources (Echols, 1995). Warwick and others 

(2000) reported that desorption of cuttings from 

the Oak Hill lignite at a depth of about 2,500 feet 

in Mississippi contained an average of 19 

Standard cubic feet (Scf)/ton of gas. However, 

strata containing lignite beds are not buried this 

deeply in the subsurface of western Kentucky and 

Tennessee (Cushing and others, 1964) and 

presumably would not produce gas. More data are 

needed to characterize the coal bed methane 

potential of lignites in the Jackson Purchase area 

and in western Tennessee. 

Conclusions 

The Jackson Purchase area of western 

Kentucky encompasses an area of 2,356 mi2 and 

includes eight counties underlain predominantly by 

alluvial sand, silt, and clay. Lignite beds and 

lignitic clays occur in the Tertiary Wilcox 

Formation, Claiborne Group, and Jackson 

Formation and less frequently in the Upper 

Cretaceous McNairy Formation. Lignite occurs in 

these units or their equivalents in western 

Tennessee in an outcrop belt trending 

northeastward across the State. Lignite deposits 

have not been developed in Kentucky and 

Tennessee because they currently are not 

economical to mine, although exploration 

programs indicate that substantial reserves are 

present. Data regarding lignite coal quality in 

Kentucky and Tennessee consists of a small data 

set constituted by the analyses presented and 

discussed herein. 

Acknowledgements 

The authors thank John SanFilipo for his help 

in compiling reference material for the Tertiary 

geology of western Kentucky and Tim Keller for his 

assistance in the field. Reviews by Susan Tewalt, 

Linda Bragg, Kris Dennen, Blaine Cecil, and Jim 

Coleman improved the quality and clarity of this 

report. 

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11
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12
Figure 1. Map showing Coastal Plain deposits of the Mississippi Embayment. Outline of Mississippi 

Embayment from Cushing and others (1964). 

13
Figure 2. Generalized map of the Jackson Purchase area, western Kentucky, showing county and state 

boundaries, and USGS 7.5-minute quadrangles. Inset map shows Jackson Purchase area shaded in blue. 

Modified from Olive (1980) and Warwick and others (1997). 

14
Figure 3. Generalized stratigraphic column of the Jackson Purchase area, western Kentucky. Modified from 

Olive (1972) and Hosman (1996). 

15 
Figure 4. Generalized map of the Jackson Purchase area, western Kentucky, showing sample locations, and 

outcrop distribution of lignite-bearing McNairy Formation, Wilcox Formation, Claiborne Group, and Jackson 

Formation units. Inset map shows Jackson Purchase area shaded in blue. Modified from Olive (1980) and 

Warwick and others (1997). Sample locations are from Olive (1971), Hower and others (1990), and this report. 

16
Figure 5. Lignite bed in highwall of Kentucky-Tennessee Clay Company Sims open-pit clay mine, Carlisle 

County, Kentucky. Refer to figure 4 for location of Sims mine. Lignite bed is 3.32 feet thick where sampled. 

Samples PW-94-29, PW-94-30, and PW-94-31, discussed in the text, were collected at this locality. 

17
Figure 6. Lignite isopach map of part of the Sims mine, Kentucky-Tennessee Clay Company, Milburn 

quadrangle, Carlisle County, Kentucky. Data courtesy of L.G. Kirk, Kentucky-Tennessee Clay Company (written 

communication, 1994). Lignite thickness contoured in one foot intervals. Refer to figure 4 for location of Sims 

mine. 

18
Figure 7. Generalized map of western Tennessee showing sample locations, county boundaries, and outcrop 

distribution of lignite-bearing McNairy Formation and Wilcox and Claiborne Group lithologies. Inset map 

shows western Tennessee shaded in blue. Modified from Russell and Parks (1975) and Warwick and others 

(1997). 

19
Figure 8. Generalized Upper Cretaceous to Holocene stratigraphic column showing lignite-bearing lithologies 

of Gulf Coastal Plain geologic units, western Tennessee. Modified from Russell and Parks (1975) and Parks 

and Carmichael (1990a, 1990b). Fm = Formation. 

20 
Figure 9. Lignite bed in highwall of Spinks Clay Company Swaim open-pit clay mine, Henry County, 

Tennessee. Refer to figure 7 for location of Swaim pit. Lignite bed is four and three quarters feet thick. 

Samples PW-94-16, PW-94-17, and PW-94-18, discussed in the text, were collected at this locality. 

21
Figure 10. Gross calorific values (moist, mineral-matter-free basis) of western Kentucky and Tennessee 

lignites. Samples J-15141 and J-15142 are from Olive (1971). Values for the average and maximum Gulf 

Coast lignite were compiled from Bragg and others (1998). [n = number of samples; Btu/lb = British thermal 

units per pound]. 

22
Figure 11. Ash yield (dry basis) of western Kentucky and Tennessee lignites. Samples J-15141 and J-15142 

are from Olive (1971) and samples 7458 through 7550 are from Hower and others (1990). Values for the 

average and maximum Gulf Coast lignite were compiled from Bragg and others (1998). [n = number of 

samples]. 

23
Figure 12. Sulfur content (dry basis) of western Kentucky and Tennessee lignites. Samples J-15141 and J15142 are from Olive (1971) and samples 7458 through 7550 are from Hower and others (1990). Values for the 

average and maximum Gulf Coast lignite were compiled from Bragg and others (1998). [n = number of 

samples]. 

24
Figure 13. HAPs concentrations in western Kentucky and Tennessee lignite samples. Values on whole-coal, 

remnant moisture basis (approximately equal to as-determined). Values for the average and maximum Gulf 

Coast lignite were compiled from Bragg and others (1998). [n = number of samples; ppm = part per million]. A) 

arsenic, B) beryllium, C) cadmium; concentrations of cadmium in samples PW-94-20 and PW-94-21 were 

below detection limits (~0.2 ppm), D) chromium, E) cobalt, F) mercury. 

25 
Figure 14. HAPs concentrations in western Kentucky and Tennessee lignite samples. Values on whole-coal, 

remnant moisture basis (approximately equal to as-determined). Values for the average and maximum Gulf 

Coast lignite were compiled from Bragg and others (1998). [n = number of samples; ppm = part per million]. A) 

manganese, B) nickel, C) lead, D) antimony, E) selenium, F) uranium. 

26 
Figure 15. Photomicrographs of western Kentucky and Tennessee lignite samples. All in incident white light 

under oil immersion except (F) which is in incident blue light. A) Jackson Fm. funginite, B) Claiborne Grp. 

funginite, C) detrohuminite, D) texto-ulminite, E) textinite A, F) same field of view as (E) under blue light. 

27 
Figure 16. Photomicrographs of western Kentucky and Tennessee lignite samples. All in incident blue light 

under oil immersion. A) Claiborne Grp. sporinite, B) Jackson Fm. sporinite, C) resinite, D) Claiborne Grp. 

suberinite, E) Jackson Fm. suberinite, F) Jackson Fm. alginite. 

28 
Table 1. Proximate and ultimate analytical data (as-received basis) for western Kentucky and Tennessee lignite samples an

work and from Olive (1971). Abbreviations; Moist = moisture, Ash = ash yield, VM = volatile matter, FC = fixed carbon, H = hnitrogen, S = sulfur, O = oxygen, n.d.= no data, Btu/lb = British thermal units per pound. Sample locations are shown in figu

Forms o

Sulfur 

Sample Formation Moist Ash VM FC H C N S O Calorific Sulfate Pyritic 

percent percent percent percent percent percent percent percent percent Value percent percen

(Btu/lb) 

Swaim pit, TN Roberts pit, TN Sims pit, KY PW-94-29 Jackson 45.42 13.02 26.18 15.38 7.61 28.48 0.31 1.15 49.43 4980 0.22 0.44 

PW-94-30 Jackson 39.15 27.68 22.43 10.74 6.33 21.95 0.47 0.47 43.34 3790 0.03 0.03 PW-94-31 Jackson 42.45 18.10 27.72 11.93 7.27 28.10 0.26 0.42 45.85 5060 0.05 0.01 PW-94-20 Claiborne 44.09 17.77 23.88 14.26 7.14 26.65 0.25 0.50 47.69 4620 0.00 0.01 PW-94-21 Claiborne 46.19 10.76 28.76 14.29 7.97 30.91 0.28 0.53 49.85 5440 0.01 0.01 PW-94-22 Claiborne 45.25 10.62 29.85 14.28 8.20 31.51 0.26 0.53 48.88 5760 0.01 0.02 PW-94-23 Claiborne 40.78 20.02 27.88 11.32 6.94 27.25 0.26 0.62 44.91 4870 0.01 0.06 PW-94-16 Claiborne 41.42 20.73 21.95 15.90 6.79 26.27 0.28 0.51 45.42 4610 0.01 0.01 PW-94-17 Claiborne 45.17 9.58 31.69 13.56 8.42 32.10 0.24 0.51 49.15 5940 0.01 0.01 PW-94-18 Claiborne 40.67 21.88 25.75 11.70 7.10 25.27 0.25 0.54 44.96 4450 0.01 0.03 

J-15141 Claiborne 48.9 9.2 25.8 16.1 8.0 27.9 0.4 2.5 52.0 5080 n.d. n.d. J-15142 Claiborne 51.8 5.7 25.6 16.9 8.3 29.6 0.4 0.7 55.3 5240 n.d. n.d. 
Table 2. Proximate and ultimate analytical data for western Kentucky and Tennessee lignite samples 

discussed in this report. Abbreviations; S = sulfur, Ash = ash yield, n.d. = no data, Btu/lb = British thermal 

units per pound. Sample locations are shown in figures 4 and 7. Data are reported on a dry basis (ash yield, 

sulfur, and sulfur forms), and moist, mineral-matter-free basis (calorific value). 

Forms of Sulfur 

Sample Formation Ash 

(percent) S (percent) 

Calorific 

Value 

(Btu/lb) 

Rmax 

Sulfate 

(percent) 

Pyritic 

(percent) 

Organic 

(percent) Source of Data 

PW-94-29 

PW-94-30 

Si

PW-94-31 ms pit, KY 

PW-94-20 

PW-94-21 

PW-94-22 

Roberts pit, TN 

PW-94-23 

PW-94-16 

PW-94-17 

PW-94-18 

Swaim pit, TN 

J-15141 

J-15142 

7458 

7459 

7460 

7461 

7462 

7463 

7464 

7465 

7466 

7546 

7550 

7457 

Jackson 

Jackson 

Jackson 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

Claiborne 

McNairy 

23.86 

45.48 

31.35 

31.78 

19.99 

19.40 

33.80 

35.39 

17.47 

36.88 

18.40 

11.80 

15.69 

20.03 

26.13 

22.55 

58.58 

29.10 

40.97 

59.01 

27.38 

27.73 

8.19 

52.96 

2.10 

0.78 

0.73 

0.89 

0.99 

0.98 

1.05 

0.88 

0.92 

0.90 

4.80 

1.40 

1.97 

4.07 

1.08 

1.93 

0.66 

3.48 

2.95 

0.58 

4.47 

1.01 

2.56 

1.10 

5,766 

5,397 

6,278 

5,709 

6,147 

6,492 

6,202 

5,926 

6,616 

5,809 

5,587 

5,569 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

0.24 

n.d. 

0.23 

0.26 

0.29 

0.25 

n.d. 

0.29 

0.28 

n.d. 

n.d.

n.d.

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

n.d. 

0.41 

0.04 

0.08 

0.00 

0.01 

0.02 

0.01 

0.02 

0.01 

0.02 

n.d 

n.d 

0.01 

0.50 

0.05 

0.08 

0.00 

0.29 

0.31 

0.00 

0.12 

0.07 

0.05 

0.00 

0.80 

0.04 

0.02 

0.02 

0.03 

0.03 

0.10 

0.02 

0.02 

0.06 

n.d 

n.d 

0.06 

1.82 

0.11 

1.35 

0.61 

1.69 

1.64 

0.07 

1.88 

0.15 

0.01 

0.60 

0.89 

0.70 

0.63 

0.87 

0.95 

0.93 

0.94 

0.84 

0.89 

0.82 

n.d 

n.d 

1.90 

1.75 

0.92 

0.50 

0.05 

1.50 

1.00 

0.51 

2.47 

0.79 

2.50 

0.50 

this report 

this report 

this report 

this report 

this report 

this report 

this report 

this report 

this report 

this report 

Olive, 1971 

Olive, 1971 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

Hower and others, 1990 

30
Table 3. Major element analytical data [whole-coal, remnant moisture basis (approximately equal to as-determined)] for w

Tennessee lignites analyzed for this work and from Hower and others (1990). Sample locations are shown in figures 4 and 7n.d. = no data]. 

 Sample Formation Ash (percent) SiO2 (percent) Al2O3 (percent) CaO (percent) MgO (percent) Na2O (percent) K2O (percent) Fe2O3 (percent) TiO2 (percent) P2O5 (percent) 

PW-94-29 PW-94-30 PW-94-31 

Jackson Jackson Jackson 

21.50 

43.20 

28.60 

9.03 

22.90 

16.30 

6.45 

12.96 

7.15 

0.49 

0.48 

0.46 

0.21 

0.39 

0.23 

0.03 

0.06 

0.04 

0.11 

0.40 

0.13 

2.15 

1.21 

0.86 

0.24 0.56 0.72 

0.02 0.03 0.03 

PW-94-20 PW-94-21 PW-94-22 PW-94-23 

Claiborne Claiborne Claiborne Claiborne 

29.20 17.50 18.40 31.80 

17.52 

7.88 8.65 

16.22 

5.55 

5.78 5.34 

10.49 

0.47 

0.49 0.48 

0.51 

0.15 0.17 0.16 0.25 

0.02 0.02 0.03 0.05 

0.05 0.06 0.10 0.26 

0.64 0.70 0.63 0.95 

1.55 0.46 0.46 0.76 

0.05 0.02 0.02 0.05 

7458 7459 7460 7461 7462 7463 7464 

7465 7466 7546 7550 

Claiborne Claiborne Claiborne Claiborne Claiborne Claiborne Claiborne 

Claiborne Claiborne Claiborne Claiborne 

15.69 20.03 26.13 22.55 

58.58 

29.10 

40.97 

59.01 

27.38 27.73 8.19 

9.25 9.15 

12.61 

9.83 

43.43 

13.83 

22.55 

38.03 

11.60 15.14 

3.01 

5.08 3.56 

7.20 

5.25 

10.12 

7.76 

11.60 

17.02 

7.93 7.93 

2.66 

0.06 0.26 

1.41 

1.60 

1.00 

0.86 

0.67 

0.57 

0.62 1.12 

0.60 

0.02 0.02 0.67 0.70 

0.57 

0.20 

0.23 

0.35 

0.18 0.33 0.12 

0.02 0.02 0.03 0.02 

0.06 

0.03 

0.04 

0.06 

0.03 0.03 

n.d. 

0.14 0.07 0.16 0.06 

0.19 

0.13 

0.32 

0.66 

0.13 0.19 

0.06 

0.33 6.48 1.69 2.88 

1.85 

4.41 

4.52 

1.04 

5.59 0.79 

0.16 

0.32 0.26 0.45 0.43 

0.90 

0.40 

0.75 

1.23 

0.39 0.42 

0.19 

0.02 0.02 0.03 0.03 

0.05 

0.03 

0.05 

0.07 

0.03 0.02 0.01 

7457 McNairy 52.96 37.37 10.31 0.20 0.05 0.05 0.29 3.72 0.94 0.05 

Roberts pit, TN Sims pit, KY 
Table 4. Trace element analytical data [whole-coal, remnant moisture basis (approximately equal to as-determined)] for we

Kentucky and Tennessee lignites analyzed as part of this work. All values in parts per million (ppm) except ash yield. AbbreAsh = ash yield, n.a. = not analyzed. < and > = qualified value (for analyses where concentration of element was below detelimit of instrument, value was assumed to be 0.7 of detection limit; for analyses where concentration of element was reportgreater-than value, value was assumed to be greater-than value - see Bragg and others (1998) for additional explanation). Slocations are shown in figure 4 and figure 7. 

Ash 

Sample Formation (percent) Ag As Au B Ba Be Bi Cd Cl Co Cr Cs Cu Ga Ge Hg 

Roberts pit, TN Si

ms pit, KY Roberts pit, TN Si

ms pit, KY PW-94-29 Jackson 21.5 0.3 6 <0.5 13 215 9 0.5 0.4 n.a.. 7 26 1.0 26 10 6.9 0.67 

PW-94-30 Jackson 43.2 0.8 6 <0.9 19 207 6 1.0 0.5 n.a. 5 60 4.8 56 22 2.5 0.30 PW-94-31 Jackson 28.6 0.9 7 3.4 11 220 9 0.9 0.2 n.a. 11 40 1.0 43 16 2.2 0.39 

PW-94-20 Claiborne 29.2 1.4 8 2.7 21 251 5 0.9 <0.04 n.a. 3 35 0.4 22 24 26.9 0.71 PW-94-21 Claiborne 17.5 0.8 6 2.1 12 245 4 0.9 <0.03 n.a. 2 23 0.6 30 13 6.3 0.54 PW-94-22 Claiborne 18.4 0.4 8 1.0 14 239 4 0.4 0.4 n.a. 5 28 1.0 26 9 6.6 0.72 

PW-94-23 Claiborne 31.8 0.5 9 1.0 16 293 5 0.7 0.3 n.a. 4 64 2.5 48 18 4.1 0.39 

Ash 

Sample Formation (percent) Mo Nb Ni Pb Rb Sb Sc Se Sn Sr Te Th Tl U V Y PW-94-29 Jackson 21.5 2 8 19 28 7 0.9 8 3.24 2 65 0.1 9 0.9 4 49 30 PW-94-30 Jackson 43.2 4 20 17 33 34 1.4 12 3.94 4 86 <0.15 15 0.6 6 108 29 PW-94-31 Jackson 28.6 4 17 27 29 8 1.5 10 6.68 4 77 0.2 14 1.0 4 92 43 PW-94-20 Claiborne 29.2 10 >58.4 11 44 3 2.9 11 5.66 12 137 0.2 24 0.2 9 111 58 PW-94-21 Claiborne 17.5 4 26 9 25 4 1.4 8 4.96 8 68 <0.06 23 0.1 8 53 46 

PW-94-22 Claiborne 18.4 2 14 7 18 6 1.1 7 5.08 3 81 0.1 10 0.2 3 50 29 

PW-94-23 Claiborne 31.8 3 19 12 32 15 1.7 16 5.29 5 114 <0.11 16 0.4 6 99 35 
Appendix: Palynological Data 

By Douglas J. Nichols 

Field No. 	 U.S. Geological Locality Results 

Survey No. 

PW-94-16 R4939-B 	 Swaim clay pit, Cutinite abundant, palynomorphs sparse; 

Weakly Co., TN assemblage dominated by lalongate 

(36°11.59’N, tricolporate pollen, tetracolporate species 

88°39.43’W) of saptotaceous affinity common, also 

present are Momipites (M. tenuipolus and 

M. sp.), Caryapollenites prodromus, and 

Symplocos?. Age middle Eocene. 

PW-94-17 R4939-C Same as above Same assemblage as R4939-B. Age: 

middle Eocene. 

PW-94-18 R4939-D Same as above Same assemblage as R4939-B. Age: 

middle Eocene. 

PW-94-20 R4940-A Roberts Pit, Weakly Cutinite abundant, palynomorphs sparse: 

Co., TN (36°11.33’N, assemblage includes many species of 

88°40.86’W) prolate tricolporates and tetracolporates 

along with Symplocos?. Age: middle 

Eocene 

PW-94-21 R4940-C Same as above Coarse and fine cuticular debris common; 

assemblage is dominated by tricolporate 

pollen, Momipites and Caryapollenites 

(“prodromus group” of Frederiksen) are 

present along with the triporate 

Symplocos?. Age: middle Eocene. 

PW-94-22 R4940-D Same as above Poor preparation with much organic 

matter but few palynomorphs; essentially 

the same assemblage as in other samples 

from this locality. Age: middle Eocene. 

PW-94-23 R4940-E Same as above Organic matter abundant, palynomorphs 

sparse, essentially the same assemblage 

as in other samples from this locality. 

Age: middle Eocene. 

33
PW-94-29 R4942-A Sims pit, Carlisle Co., Organic matter abundant; assemblage 

KY (36°49.58’ N, dominated by prolate tricolporate pollen, 

88°53.42’ W) sapotaceous tetracolporates also 

common, two species of Momipites 

present. Age: middle Eocene. 

PW-94-30 R4942-B Same as above Same assemblage as in R4942-A. Age: 

middle Eocene. 

PW-94-31 R4942-C Same as above Organic matter abundant, palynomorphs 

sparse; Essentially the same assemblage 

as in other samples collected from this 

locality. Age: middle Eocene. 

34