Kansas Geological Survey, Current Research in Earth Sciences, Bulletin 253, part 1
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Palynological Correlation of Atokan and Lower Desmoinesian Coals Between Kansas and Illinois and Other Coal Basins

Analytical Procedure for Coals in the Forest City Basin Core

Six coal samples from the Kansas Geological Survey Edmonds 1A core drilled in the NW SW sec. 35, T. 9 S., R. 22 E., Leavenworth County, Kansas, in the western part of the Forest City basin were palynologically analyzed. Also, one coal sample from each of three other cores drilled in Cherokee County, Kansas, were macerated and studied (fig. 1, table 1). Later, samples from seven carbonaceous shale intervals in the Kansas Geological Survey core were macerated. The samples were taken from all the carbonaceous shales in the 82-ft-thick interval in the Leavenworth County core between the coal beds of macerations 3289B and C. These sample locations of carboniferous shales and lower coals are shown on the Edmonds 1A core in the north-south profile of Cherokee Group rocks and older Pennsylvanian rocks across eastern Kansas (fig. 2).

Figure 1--Location of wells containing coal beds and carbonaceous shale bands that were sampled and macerated for study. 1) KGS Edmonds No. 1A; 2) Gulf Oil Corp., Pittsburg & Midway PM-1; 3) Gulf Oil Corp., Pittsburg & Midway PM-7; 4) Gulf Oil Corp., Pittsburg & Midway PM-12; and location of the profile of the Cherokee Group in eastern Kansas as shown in fig. 5. General figure modified from Wright (1975).

Table 1--Location of wells and depths from which macerated coal samples and carbonaceous shale samples were obtained.

Figure 2--North-south profile of Cherokee Group in eastern Kansas. Portions of the profile are modified from Huffman (1991). A larger Acrobat PDF version (384 kB) of this figure is available.

The coal samples were macerated with Schultze's solution and 5% KOH solution. Shale samples were treated with 10% HCl solution to dissolve carbonate minerals and then with HF acid to dissolve the silicate minerals. Macerated residues were centrifuged in 1.9 SG solution of zinc chloride to separate undissolved mineral matter from organic remains. Microscope slides of the spore residues were examined until no new taxa were observed on an entire slide. A count was made of 200 specimens in each maceration to determine the relative abundance of taxa in the spore assemblages.

Correlations were based on first and/or last occurrence of 31 spore species and major changes in relative abundance of several taxa. Stratigraphic ranges and relative abundance of spores in the Kansas cores were compared with their ranges and abundance in Iowa, Illinois basin, and the Missouri and Kansas portions of the Forest City basin; coal areas in the Appalachian coal region; and in Europe. Previous palynological studies of Smith and Butterworh (1967), Clayton et al. (1977), Ravn (1986), Kosanke (1988), Eble (1994), Peppers (1984, 1996) and Peppers et al. (1993) were especially useful. Some differences in chronostratigraphic ranges were expected when comparing palynologic floras in coal as well as in shale because of differences in environments of deposition. Nevertheless, no major inconsistencies in spore ranges, when compared with those in other regions were encountered.

Palynological Study of Atokan and Lower Desmoinesian Coals and Carbonaceous Shales in the Forest City Basin Core

The coal between 1,164.3 and 1,164.6 ft (354.9-355 m) (maceration 3289A--summarized in table 2) in the Kansas Geological Survey Edmonds 1A core (Leavenworth County, Kansas) is 30 ft (9 m) above the base of the Pennsylvanian. It is early Atokan (early Westphalian B) in age and correlates approximately with the Bell coal bed in the Illinois basin (fig. 3). This coal correlates with the lower part of the Microreticulatisporites nobilis-Endosporites globiformis (NG) Spore Assemblage Zone in the Illinois basin (Peppers, 1984). Schulzospora rara, which is an index spore for the Lower Pennsylvanian (midcontinent usage), was not observed in the coal. The species extends to the top of the Morrowan in the Illinois basin (Peppers, 1984), the top of the "McLouth Sandstone" in the Missouri part of the Forest City basin (Peppers et al., 1993), the lower part of the Middle Pennsylvanian in the Appalachian region (Kosanke, 1988) (NOTE: U.S. Geological Survey usage places the Lower-Middle Pennsylvanian boundary lower in this area than where they place it in the midcontinent), and the top of the Westphalian A in Europe (Clayton et al., 1977). Sinuspores sinuatus and Waltzispora prisca occur in maceration 3289A (table 2) and extend up to a little above the Bell coal bed in the Illinois basin (Peppers, 1996). Both species occur in an unnamed formation in the lower part of the Atokan in the Forest City basin in northwestern Missouri (Peppers et al., 1993). Sinuspores sinuatus was recorded in the Caseyville Formation and lower part of the Atokan Kilbourn Formation in Iowa (Ravn, 1986). Kosanke (1988) reported Punctatisporites sinuatus (=Sinuspores sinuatus) as extending up to the Hernshaw coal bed (now called Fireclay coal) in the middle of the Kanawha Formation (upper Westphalian B) in West Virginia. The species disappears at the top of Westphalian A (Smith and Butterworth, 1967) to lower Westphalian B (Coquel, 1976) in Europe.

Table 2--Palynology of Atokan and early Desmoinesian coal beds and carbonaceous shale bands in the KGS Edmonds No. 1A core from Leavenworth County, Kansas. Numbers are percent of taxon in the spore assemblage, and "X" indicates taxon present but not observed in spore count.

Figure 3--Chronostratigraphic ranges of selected spore species in Atokan and early Desmoinesian coals and carbonaceous shale bands in the KGS Edmonds No. 1A core compared with their chronostratigraphic ranges in the Illinois basin. A larger Acrobat PDF version (1.2 MB) of this figure is available.

Punctatosporites minutus and Vestispora pseudoreticulata also occur in the oldest coal in the core, and they first appear near the bases of the Tradewater Formation and Atokan Stage in Illinois. Vestispora pseudoreticulata occurs for the first time near the base of the Kilbourn Formation in Iowa (Ravn, 1986) and in the lower Atokan in the Missouri portion of the Forest City basin. It begins its range in the River Gem coal bed in eastern Kentucky and in the Coal Creek coal bed in eastern Tennessee, which are approximately correlative with the Bell coal in the Illinois basin (Phillips and Peppers, 1984). Punctatosporites minutus first appears in the Gilbert coal bed in the lower part of the Middle Pennsylvanian in West Virginia (Kosanke, 1988). In western Europe P. minutus and V. pseudoreticulata begin their ranges, depending on location, in the middle Westphalian A to lower Westphalian B. Maceration 3289A also contains Endosporites globiformis, which first appears at the base of the Atokan in the Illinois basin, Iowa, and the eastern part of the Forest City basin. In eastern Kentucky and Tennessee, it was first observed in the lower part of the Middle Pennsylvanian (Peppers, 1996). In West Virginia, Kosanke (1984) reported that E. globiformis appears in the Cedar Grove coal bed in the lower part of the Middle Pennsylvanian (U.S Geological Survey usage), but Eble (1996) reported it in coals in Virginia as old as Early Pennsylvanian. The range of the species begins at the Westphalian A-B boundary in Great Britain (Smith and Butterworth, 1967). Simozonotriletes intortus and Grumosisporites varioreticulatus, which became extinct in the late Atokan in the Illinois basin and Iowa, were observed in the coal sample.

The coal at 1,157.5 to 1,157.8 ft (352.8-352.9 m) (maceration 3289B) in table 2 is only 7 ft (2 m) above the oldest coal. Except for Savitrisporites concavus, which extends into the middle Atokan in Illinois, no additional spore taxa of stratigraphic significance appear in the coal.

The carbonaceous shale band (maceration 3295A) at 1,149 ft (350 m) is correlated with the middle of the Microreticulatisporites nobilis-Endosporites globiformis (NG) Spore Assemblage Zone in the Illinois basin. Pilosisporites aculeolatus and Cyclogranisporites aureus appear for the first time. Pilosisporites aculeolatus begins its range in an unnamed coal a little below the middle of the Atokan in the Kentucky part of the Illinois basin (Peppers, 1984) and in an unnamed coal in the Kilbourn Formation of Iowa. It first appears in an unnamed lower Atokan sequence above the "McLouth Sandstone" in the Missouri portion of the Forest City basin (Peppers et al., 1993). In the Appalachian region Pilosisporites triquetrus, which is probably synonymous with P. aculeolatus, was first reported in the Powellton coal bed in the middle of the Kanawha Formation of West Virginia (Kosanke, 1988) and in the Blue Gem coal bed in Tennessee (Phillips and Peppers, 1984). Pilosisporites triquetrus appears for the first time in Great Britain in upper Westphalian B coals (Smith and Butterworth, 1967). Cyclogranisporites aureus begins its range a little earlier (lower part of the Atokan) in the Illinois basin than in eastern Kansas. In Iowa it occurs in the lower part of the Kilbourn Formation, and in the eastern part of the Forest City basin, it was first observed in the middle of the lower half of the Atokan. Kosanke (1988) reported the first occurrence of the species in West Virginia in the Powellton Coal. Endosporites staplinii and Knoxisporites triradiatus, which disappear in the upper Atokan, were noted in maceration 3295A (table 2). Crassispora cf. kosankei, which is a large form of the species, was also observed in maceration 3295A. It occurs in the lower Atokan in the Illinois and Forest City basins.

Several important palynological events occur in the short interval between 1,125.2 and 1,132.9 ft (343-345 m) in which four thin carbonaceous shale bands occur (macerations 3295 B-E, table 2). The shales of macerations 3295 B-D are correlated with the upper part of the Microreticulatisporites nobilis-Endosporites globiformis Spore Assemblage Zone in the Illinois basin. Punctatisporites minutus, which is one of the most common spores from the lower part of the Middle Pennsylvanian through the remainder of the period, appears in maceration 3295B. Ravn (1986) reported P. minutus in Iowa coal beds as old as Morrowan in age, but the illustrated specimens (Ravn, 1986) may belong to a similar species, Cyclogranisporites minutus. Punctatisporites minutus first occurs in the lower one-third of the Atokan in Illinois and Missouri. Verrucosisporites sifati and Endosporites plicatus also appear for the first time in maceration 3295B. These two species appear just below the Smith coal bed, which is about middle Atokan in age in the Illinois basin. They appear a little earlier than the middle of Atokan in the eastern part of the Forest City basin. In Iowa, Ravn (1986) reported that V. sifati and E. plicatus occur near the end of the Atokan. In the Appalachian region V. sifati appears in the Coal Creek coal bed in the Slatestown Formation in Tennessee (Peppers, 1996). Endosporites plicatus appears in the upper part of the Kanawha Formation in the Appalachian region. Alatisporites pustulatus, which also occurs in maceration 3295B, begins its range just below the middle Atokan in Illinois and the Missouri part of the Forest City basin. In Iowa it begins near the base of the Atokan.

Laevigatosporites globosus was recorded for the first time in the shale band macerated as 3295D (table 2). It appears a little below middle Atokan in the Illinois basin. It occurs in the upper Atokan, which is equivalent to the Westphalian C, in Iowa (Ravn, 1986) and the eastern part of the Forest City basin. It appears in the Redoak Mountain Formation in Tennessee (Phillips et al., 1985) and in the upper part of the Kanawha Formation in West Virginia (Eble, 1994). Latosporites globosus, which is synonymous with Laevigatosporites globosus, also appears in middle Westphalian C in Great Britain (Smith and Butterworth, 1967). Vestispora pseudoreticulata becomes extinct above the shale of maceration 3295D. It extends to the top of the Atokan in the Illinois basin and up to the Stockton "A" coal bed near the base of the Charleston Sandstone in the Appalachian coal region. According to Ravn (1986), it ranges well up into the Desmoinesian in Iowa. Vestispora pseudoreticulata extends to the top of Westphalian C in Europe. Apiculatasporites variocorneus, which disappears in the upper Atokan in the Illinois basin and Iowa, was also observed in maceration 3295D.

The shale band (maceration 3295E, table 2) at 1,125.2 ft (343 m) is correlated with the lower part of the Torispora securis-Vestispora fenestrata (SF) Spore Assemblage Zone and middle Atokan in the Illinois basin (Peppers, 1984). Triquitrites sculptilis, T. bransonii, Spinosporites exiguus, Latosporites minutus, Microreticulatisporites sulcatus, Vestispora fenestrata, and Torispora securis appear for the first time in the shale. All but T. sculptilis, which appears a little below the middle of the Atokan, begin their ranges in the middle Atokan in the Illinois basin. Triquitrites sculptilis appears in the Kilbourn Formation of Iowa and in the middle Atokan in the eastern part of the Forest City basin. The species appears in the Hernshaw coal (Kosanke, 1988) and Lower Chilton coal (Eble, 1994) of West Virginia and in the Big Mary coal bed in Tennessee, which correlate with the middle Atokan (Peppers, 1996). It appears in the upper Westphalian A (?) to upper Westphalian B (Paproth et al., 1983) in Europe. Spinosporites exiguus appears in the upper Atokan in Iowa (Ravn, 1986), and the upper part of the lower Atokan in Missouri and in the Windrock coal bed in Tennessee. Latosporites minutus also appears in the Windrock coal and in the middle of the upper Atokan in Missouri.

Triquitrites bransonii begins its range in the middle Atokan in Illinois (fig. 3). It appears in the Chilton "A" coal bed in West Virginia (Kosanke, 1988), and in the upper Pioneer coal bed in Tennessee, which are middle Atokan in age. It occurs for the first time in Great Britain a little later, in middle Westphalian C. Microreticulatisporites sulcatus is a guide fossil for the middle Atokan and younger rocks in Illinois. It was recorded with reservation in the upper Atokan of Iowa (Ravn, 1986). It appears at about the middle of the Kanawha Formation in West Virginia (Eble, 1994). The Windrock coal, which is a little older than middle Atokan, is the oldest coal in Tennessee that contains M. sulcatus. Smith and Butterworth (1967) reported the first occurrence of the species in lower Westphalian C coals in Great Britain. Vestispora fenestrata appears in middle Atokan coals in Illinois and in the Kilbourn Formation in Iowa but does not appear until the middle of the upper half of the Atokan in the Missouri part of the Forest City basin (fig. 3).

It is first observed in the Hernshaw coal in West Virginia (Kosanke, 1988) and the upper Pioneer coal bed in Tennessee, both of which are slightly older than middle Atokan (Peppers, 1996). Vestispora fenestrata begins its range in lower Westphalian C coal beds in Europe (Clayton et al., 1977; Paproth et al., 1983).

Torispora securis, which begins its range in the middle Atokan in Illinois, is rare in the Forest City basin of Missouri as it was observed in only one coal. It does not occur until late Atokan in Iowa (Ravn, 1986) and equivalent coals in the Appalachian coal region (Eble and Gillespie, 1989; Kosanke, 1988; Peppers, 1996). The beginning of the range of Torispora is considered a good marker for the lower Westphalian C (Clayton et al., 1977; Paproth et al., 1983).

Ahrensisporites guerickei var. ornatus occurs for the last time in the shale of maceration 3295E in eastern Kansas. In the Illinois basin, it extends to the Mariah Hill Coal Member in the upper part of the Atokan. In Iowa, A. guerckei var. ornatus disappears between the middle and upper Atokan. It extends to the Pine Bald coal bed in Tennessee (Phillips and Peppers, 1984) and the Coalburg coal bed in West Virginia (Kosanke, 1988), both of which correlate with the upper Atokan. In Europe it extends to middle Westphalian C coals. Lophotriletes rarispinosus, which first appears in the middle Atokan in the Illinois basin, also occurs in maceration 3295E.

No coals or carbonaceous shales with spore assemblages occur between the shales of macerations 3295E and G, an interval of about 37 ft. Thus, no palynological data were obtained from the core between the middle and upper part of the Atokan.

The carbonaceous shale of maceration 3295G correlates with about the middle of the Radiizonates difformis (RD) Spore Assemblage Zone in the Illinois basin and is late Atokan in age. The shale marks the beginning of the stratigraphic range of Cyclogranisporites orbicularis and the only occurrence of Radiizonates rotatus and R. difformis. In Illinois the latter two species are found in only the Pope Creek and Tarter Coal Members. In Indiana they appear in the Upper Block and Lower Block Coal Members, which are equivalent to the Illinois coals, and the Mariah Hill Coal, which is slightly older than the Tarter Coal. In Iowa Radiizonates difformis appears in the upper Atokan Blackoak Coal, which is approximately correlative with a position between the Pope Creek and Rock Island (No. 1) Coals. No coal beds equivalent to the Tarter or Mariah Hill Coals have been identified in Iowa. The Radiizonates rotatus-R. difformis interval is thicker in the Appalachian region and contains more coals than in Illinois. The interval extends from the Winifrede to the Stockton coal beds in the Kanawha Formation in West Virginia (Eble, 1994), although Kosanke (1988) reported that the species appears slightly earlier, in the Chilton "A" coal bed. It ranges from the Hazard No. 6 coal bed to Hazard No. 9 coal bed in eastern Kentucky and from the Coal Gap coal bed to an unnamed coal at the top of Cross Mountain in Tennessee (Peppers, 1996). All of these coals are equivalent in age to late Atokan.

Cyclogranisporites orbicularis first appears in the Mariah Hill Coal in the Illinois basin and the Blackoak Coal in Iowa, which are late Atokan in age. It began its stratigraphic range in the Peewee coal bed of Tennessee and in the Hazard No. 7 coal bed in eastern Kentucky, which are both late Atokan in age. Cyclogranisporites obliquus, which merges with some forms of C. orbicularis, appears in upper Westphalian C coals in Great Britain (Smith and Butterworth, 1967), but it has been reported in lower Westphalian C coals (Loboziak, 1971).

Dictyotriletes bireticulatus, Densosporites annulatus, Cristatisporites indignabundus, and Savitrisporites nux disappeared above the shale macerated as 3295G. The later two species disappeared above the Pope Creek Coal in Illinois and above the Blackoak Coal in Iowa. These two coals are late Atokan in age. Cristatisporites indignabundus disappears in the upper part of the unnamed upper Atokan succession in the Forest City basin (Peppers et al., 1993). It last occurs in the Coalburg coal in West Virginia, the Peewee coal in Tennessee, and the Hazard No. 7 coal and Princess No. 6 coal bed (Kosanke, 1973) in Kentucky, which are all late Atokan in age. Cristatisporites indignabundus extended to the end of Westphalian C in Europe (Loboziak, 1971; Coquel, 1976). Savitrisporites nux is so rare in the Forest City basin in Missouri that its range cannot be determined there. It disappears above the Princess No. 5 coal bed in northeastern Kentucky (Kosanke, 1973) and the Rock Springs coal bed in Tennessee. In Europe its range reaches almost to the top of Westphalian C.

Densosporites annulatus last occurs in the Tarter Coal in Illinois and in the Lower Block Coal in Indiana. It extends to the Blackoak Coal in Iowa and to almost the top of the Atokan in the Forest City basin in Missouri. It disappears above the Lower No. 5 Block coal bed (Kosanke, 1988) in the Pennsylvanian stratotype in West Virginia proposed by the U.S. Geological Survey (Englund et al., 1979). That coal correlates with the upper Atokan in the Illinois basin. Densosporites annulatus extends to the Hazard No. 9 coal in Kentucky and to an unnamed coal just above the Cold Gap coal in Tennessee. It ranges up to the top of Westphalian C in Europe (Loboziak, 1971; Coquel, 1976).

Dictyotriletes bireticulatus extends to the Rock Island (No. 1) coal in Illinois but extends slightly higher into an unnamed coal (formerly Indiana Coal II) directly above the Perth Limestone Member in Indiana (Peppers, 1996). It last occurs in the youngest unnamed Atokan coal in the eastern part of the Forest City basin and in the Blackoak coal in Iowa. Dictyotriletes bireticulatus disappears above the Upper No. 5 Block coal bed in West Virginia and the Hazard No. 8 coal bed in eastern Kentucky (Peppers, 1996). In Europe it extends into the basal part of Westphalian D. Savitrisporites concavus also occurs in maceration 3295G. It becomes extinct in the upper part of the Atokan in the Illinois basin and in the upper part of the Kilbourn Formation in Iowa.

The coal (macerations 3289 C-D) from 1,074.7 to 1,075.5 ft (327-328 m) (table 2) correlates with the base of the Cadiospora magna-Mooreisporites inusitatus (MI) Spore Assemblage Zone in the Illinois basin (Peppers, 1984) and is early Desmoinesian in age (fig. 3). Vestispora clara, Triquitrites minutus, and Camptotriletes confertus appear for the first time in the coal and in the earliest Desmoinesian coal beds in the Illinois basin. Vestispora clara begins its range in the Blackoak Coal, which is the youngest Atokan coal in Iowa (Ravn, 1986). In northwestern Missouri, however, it begins in the youngest Desmoinesian coal (Peppers et al., 1993). This species has not been reported in Europe.

Triquitrites minutus appears in the Blackoak Coal but was not observed in the Forest City basin in Missouri. The species was reported by Kosanke (1988) in the Upper No. 5 Block coal (early Desmoinesian) in West Virginia, but it is rare in the Applachian region. Camptotriletes confertus was observed only in macerations 3289 C and D, and in Iowa it appears only in the Blackoak Coal. It has not been reported in the Forest City basin or Appalachian coal region.

Endosporites zonalis last occurs in macerations 3289 C and D. It ranges up to the Hermon Coal Member at the base of the Desmoinesian in Illinois but was not observed in the Desmoinesian in the eastern part of the Forest City basin. The species extends up to the Laddsville Coal Member in Iowa, which is slightly younger than the Hermon Coal. In the U.S Geological Survey proposed Pennsylvanian stratotype, E. zonalis disappears above the Little No. 5 Block coal bed, which is late Atokan in age. It extends into the lower Westphalian D in Great Britain (Smith and Butterworth, 1967). A few specimens of Laevigatosporites cf. vulgaris, a thickened form of L. vulgaris, were observed in maceration 3289D. In the Illinois basin it occurs in the Lewisport coal bed near the base of the Desmoinesian.

No major changes in spore assemblages occur between the coal of macerations 3289C-D at the base of the Desmoinesian and the coal of macerations 3289E-F, which is the Riverton coal bed.

Relative Abundance of Spore Taxa in Coal and Carbonaceous Shale

The relative abundance of spore taxa can be useful in a general way in characterizing and correlating coal beds (figs. 3 and 4). Lycospora pellucida dominates the spore assemblages in the two oldest coal beds and oldest carbonaceous shale in the Kansas Geological Survey Edmonds 1A core. Lycospora granulata, Densosporites annulatus, and other lycopod spores make up most of the remainder of the assemblages in the three samples. In the Illinois basin D. annulatus is most abundant in the Reynoldsburg Coal Bed at the base of the Tradewater Formation (top of the Morrowan) and several overlying lower Atokan coal beds. Ravn (1986) noted that in Iowa the species tends to be most abundant in the lower Atokan Kilbourn Formation.

Figure 4--Relative abundance of spore taxa in coals and shale bands in the KGS Edmonds No. 1A core. Spore distribution patterns are shown according to major groups of parent plants. A larger Acrobat PDF version (320 kB) of this figure is available.

Maceration 3295B (fig. 4) of the shale band is dominated by Densosporites sphaerotriangularis at 45%, but Lycospora pellucida at 17% is still the dominant species of Lycospora. In maceration 3295C Lycospora granulata at 32% becomes the most abundant species, and Densosporites sphaerotriangularis at 18.5% is second in abundance. Although L. granulata is still the most abundant species in macerations 3295D and E, Lycospora micropapillata becomes a significant component at 16.5 and 18.5%, respectively. Lycospora granulata remains as the most abundant species in the youngest carbonaceous shale (macerations 3295G) and in the remainder of the core samples. Florinites, large species of Laevigatosporites, and fern spores including Punctatosporites minutus and Laevigatosporites globosus become important constituents in the floras for the first time. Lycospora granulata becomes even more abundant in the upper two coals reaching a maximum of 52.5% in the upper half of the coal (maceration 3289F) at the base of the Desmoinesian. Fern spores Punctatisporites minutus, Punctatosporites minutus, Latosporites minutus, Torispora securis, Triquitrites spp., and Granulatisporites spp. also became more abundant in the upper shale (maceration 3295G) and coals.

The pattern of change in dominance of three species of Lycospora in the Middle Pennsylvanian is apparently concurrent over a large area of North America (Peppers, 1979; Phillips et al., 1985; Peppers, 1996). Lycospora pellucida is dominant in Lower and lower Middle Pennsylvanian coals, up to a little below the middle of the Atokan in the Illinois and Forest City basins (Peppers et al., 1993) and in the lower part of the Middle Pennsylvanian (middle Westphalian B) in the Appalachian region. Lycospora granulata become the most abundant species of Lycospora for a brief time. This was followed by a short interval in which L. micropapillata was abundant or dominant. This marked increase in abundance of L. micropapillata also occurs in western Missouri (Peppers et al., 1993), Illinois, Kentucky, and Tennessee (Peppers, 1979), and West Virginia (Kosanke, 1988) just before the middle of the Atokan. The interval between the shales of maceration 3295B and 3295C probably represents a longer time than indicated by the thickness of the interval because in most regions several coal beds are dominated by L. granulata before L. micropapillata becomes abundant. Lycospora micropapillata declined in abundance in the middle Atokan. Lycospora granulata then became dominant again and remained so until the end of the Desmoinesian (fig. 4) at which time Lycospora essentially disappeared in North America.

A key element in spore distribution and its use in correlation is the rise of ferns, especially tree ferns. Laevigatosporites globosus and Punctatosporites minutus began to be an important part of coal swamp floras a little after the middle of the Atokan in the Illinois basin as represented by the shale of maceration 3295G in Kansas. The epibole of the two species as indicated in fig. 3 occurred somewhere between that shale and the shale of maceration 3295E because there is a relatively large interval between the two shale beds. The base of the epibole of Torispora, another tree fern spore, is at the Tarter Coal in the upper Atokan (upper Westphalian C) in Illinois and in the coal of maceration 3295G in Kansas. Punctatisporites minutus reaches epibole proportions near the end of the Atokan.

Floral Composition of Coal Swamps and Clastic Mires

As in the Illinois basin and Appalachian coal region, lycopod trees including Lepidophloios, Lepidodendron, and Paralycopodites dominated the early Atokan (Westphalian B) coal swamps and clastic wetlands. Small lycopods represented by Densosporites were very abundant in some of the mires. Tree lycopods continued to dominate in the Upper Atokan (Westphalian C) and lower Desmoinesian (Westphalian D), and smaller lycopods were rare. Tree ferns represented by Punctatisporites minutus, Punctatosporites minutus, Latosporites minutus, Laevigatosporites globosus, Torispora securis, and other minor species were not abundant until the upper Atokan. Filicalean ferns were somewhat more common in the lower Atokan than the tree ferns, but like the tree ferns they increased in abundance in the upper Atokan. Large species of Laevigatosporites, including L. vulgaris and L. desmoinesensis, produced by sphenopsids increased in abundance in the upper Atokan. Sphenopsids that produced Calamospora remained at about the same abundance throughout the Atokan and lower Desmoinesian. Florinites, the major cordaites spore, also did not undergo major changes in abundance. The abundance of seed ferns is not shown because the very large seed fern pollen Monoletes, borne by Medulosa, is not part of the small-spore population.

Coal Samples from Cores Drilled in Cherokee County, Kansas

Three additional coal samples from three closely spaced cores drilled by Gulf Oil Corporation (Pittsburg & Midway PM-1, PM-7, and PM-12) in Cherokee County, southeastern Kansas, were macerated and studied (fig. 1, table 1). Desorptions of the three Gulf-P&M cores are graphically presented in Appendix A, which is an open-file report by Harris, 1984.

Maceration 3286 is of a coal between 389.9 and 390.5 ft (118.8-119 m), 6.4 ft (1.9 m) below the Riverton coal and 17 ft (5 m) above the base of the Pennsylvanian in the Pittsburg & Midway PM-1 core. The coal is early Desmoinesian (early Westphalian D) in age and is approximately equivalent to the Lewisport coal in the Illinois basin. It contains Thymospora pseudothiessenii (fig. 5 and table 3), which begins its range at the base of the Desmoinesian in the Illinois basin. The species appears in the Upper No. 5 Block coal bed in the lower part of the Charleston Sandstone in West Virginia (Kosanke, 1988). In Europe T. pseudothiessenii is an index fossil for the base of Westphalian D. Anapiculatisporites grundensis, which also occurs in maceration 3286, first appears in the Lewisport coal in the Illinois basin. The relatively large percentage of Torispora, Punctatosporites minutus, and Triquitrites sculptilis indicates that the coal is near the Atokan-Desmoinesian boundary. Maceration 3286 lacks the Atokan taxa Dictyotriletes bireticulatus, Radiizonates difformis, R. rotatus, Savitrisporites nux, and Cristatisporites indignabundus.

Figure 5--Chronostratigraphic ranges of selected spore species in oldest Pennsylvanian coal beds in the three cores drilled in Cherokee County, Kansas, compared with the range in the Illinois basin. Coals are shown in position relative to their ages. A larger Acrobat PDF version (2.6 MB) of this figure is available.

Table 3--Palynology of oldest Pennsylvanian coal beds in three cores from Cherokee County, Kansas. Numbers are percent of taxon in the spore assemblage, and "X" indicates taxon present but not observed in spore count.

Lycopods, ferns, cordaites, and sphenopid spores are well represented in maceration 3286 (fig. 5). Lycospora granulata at 15.5% is the most abundant species. Fern spores present include Laevigatosporites globosus (6.5%), Punctatosporites minutus (5.5%), Torispora securis (5%), Cyclogranisporites orbicularis (5%), and Punctatisporites minutus (5%). The cordaitean Florinites mediapudens accounts for 10% of the spore assemblage, and the sphenopsid spores Laevigatosporites desmoinesensis and L. ovalis are at 11% each.

Maceration 3287 is a coal between 449.6 and 450.0 ft (137-137.2 m) in Pittsburg and Midway PM-7 core. It is just above the top of the Mississippian limestone and is 27.2 ft (8.3 m) below the Riverton coal. The coal is late Atokan in age. Maceration 3287 contains Densosporites annulatus (fig. 4), which extends up to the Tarter Coal in Illinois, and Vestispora fenestrata, Microreticulatisporites sulcatus, Torispora securis, and Triquitrites sculptilis, which first appear at about middle Atokan. Therefore, the coal is no older than the shale band macerated as 3295E in the Edmonds No. 1A core. Laevigatosporites globosus and Latosporites minutus are also present, but their low abundance indicates that the coal is about the same age as the shale macerated as 3295E. The coal lacks Radiizonates difformis and R. rotatus; therefore, the coal is older than the Mariah Hill Coal of Indiana.

Lycospora pellucida and L. granulata at 27.5% each are equally represented. Lycospora micropapillata and Endosporites globiformis each make up 6.5 % of the assemblage. These percentages also indicate that the coal is about middle Atokan in age because L. pellucida is replaced by L. granulata as the dominant species of Lycospora during middle Atokan, and L. micropapillata is unusually abundant slightly later. The low abundance of Punctatosporites minutus (6.5%), Punctatisporites minutus (1.5 %), Latosporites minutus (1.5%), and Triquitrites (4%) indicate that ferns were not very abundant. Laevigatosporites desmoinesensis (5.5%) and L. ovalis (5%) represented sphenopsid plants. The cordaites pollen Florinites accounts for only 2% of the assemblage.

Maceration 3288 is of a coal between 435.7 and 437.3 ft (132.8-133 m) in the Pittsburg and Midway PM-12 core. The coal directly overlies Mississippian limestone and is 25.5 ft (7.8 m) below the Riverton coal. The spore assemblage is rather poorly preserved; therefore, relative abundance of spore taxa were not determined. The coal contains Lophotriletes gibbosus, which extends to the Rock Island (No. 1) Coal in Illinois, but into the Desmoinesian in Iowa (Ravn, 1986). Triquitrites minutus (fig. 4), which first appears in the Rock Island Coal in Illinois and the Blackoak Coal in Iowa, was also observed in maceration 3288. Torispora and Triquitrites sculptilis are more abundant than in maceration 3287, which is older than the coal of 3288. The coal of maceration 3288 is close to the Atokan-Desmoinesian boundary.

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Kansas Geological Survey
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