south-central Kentucky, including the Pulaski County State .... Limestone in the reference sections in the Mississippi ... Formation in Scott County, Tennessee.
J.G. Richardson, W.I. Ausich: Miospore biostratigraphy of the Lower Mississippian in Kentucky and Indiana, U.S.A.
MIOSPORE BIOSTRATIGRAPHY OF THE BORDEN DELTA (LOWER MISSISSIPPIAN; OSAGEAN) IN KENTUCKY AND INDIANA, U.S.A.
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JEFFERY G. RICHARDSON Columbus State Community College Department of Biological & Physical Sciences Columbus, Ohio 43215 U.S.A. WILLIAM I. AUSICH The Ohio State University Department of Geological Sciences Columbus, Ohio 43210 U.S.A.
Abstract One hundred seventy-five samples from the Borden Delta provided a detailed biostratigraphic framework for part of the Lower Mississippian clastic succession in Kentucky and Indiana. The samples indicate the eastern and southern parts of the Borden Delta are correlative with the PC Biozone and CM Biozones of Western Europe respectively; however, biostratigraphical problems arise in the western part of the investigated area (Indiana). The appearance of Lycospora pusilla in the samples from southcentral Indiana is important in that it raises questions regarding the level of the Tournaisian–Visean boundary, it suggests floral provincialism in this part of North America during the Lower Mississippian, and it does not correlate with the previously established miospore zone from Western Europe.
INTRODUCTION
The Borden Delta (Mississippian; Osagean), located in the east-central United States, represents a classic, finegrained siliciclastic basin-filling succession and is some of the only siliciclastic deposition occurring during the Early Mississippian (Gutschick and Sandberg, 1983). Overall, the Borden Delta migrated west–northwest across the study area, which extends from northeastern Kentucky into central Indiana. As the delta prograded and migrated, sediments were deposited along many interfingered, timetransgressive boundaries. Most previous studies on the Borden Delta rocks were centered on the paleoecology and paleontology of macrofossils (e.g., Lane, 1973; Ausich et al., 1979; Ausich, 1983; Kammer, 1985; Ausich and Meyer, 1990). However because of the paucity of macrofossils and changing deposiPalynology, 28 (2004): 159–174 © 2004 by AASP Foundation
ISSN 0191-6122
tional setting along the Borden Delta outcrop belt, no true biostratigraphic framework exists throughout its entire succession from Kentucky into Indiana. Because of their durability and abundance, miospores are ideal suited for biostratigraphic research in fine-grained clastic successions. This study is a detailed continuation of a preliminary study conducted by Coleman and Clayton (1987) in which they concluded that the Borden Delta rocks in Kentucky and Indiana were comparable to the previously established miospore zones of Western Europe (Higgs et al., 1988; Higgs, 1996; Coleman and Clayton, 1987; Coleman, 1991). The region under investigation (Kentucky and Indiana) was divided into three smaller areas based on lithologic and sequence stratigraphic characteristics (Text-Figure 1). Borden Area I (BA-I) includes the outcrops in northwestern Kentucky; Borden Area II (BA-II) comprises the Borden Delta deposits in south-central Kentucky, including those on the shores of Lake Cumberland; and Borden Area III (BA-III) includes all the Borden Delta rocks in northcentral Kentucky and southeastern and south-central Indiana. The outcrops in BA-III are primarily located between Lexington (KY) and Bloomington (IND). Text-Figure 2 shows the general stratigraphic relationships of the rocks studied herein, and Appendix A contains descriptions of select stratigraphic sections.
MATERIALS AND METHODS One hundred seventy-five samples were processed using standard palynological techniques at the Byrd Polar Re-
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(Richardson, 2003). All the members of the Borden Delta in BA-I represent an overall upward shoaling succession, covering environments from the basin floor fan (Farmers Member) to the delta top (Nada Member) (Chaplin, 1980; Bryan, 1983; Mason, 1981; and Matchen and Kammer, 1994) (Text-Figure 2).
Miospore Biostratigraphy of BA-I
Text-Figure 1. Geographic distributions of Borden Areas I, II, and III. Each Borden Area was defined using lithologic and sequence stratigraphic characteristics. BAI includes all the outcrops in northeastern Kentucky, BAII represents the Borden Delta rocks in south-central Kentucky, and BA-III includes the Borden Delta rocks in north-central Kentucky and southern and south-central Indiana.
search Center at The Ohio State University (Litwin and Traverse, 1989). The samples yielded 58 palynomorph species representing 38 genera (Appendix B). All the described specimens are housed in the Orton Geological Museum at The Ohio State University, Columbus, Ohio.
BORDEN AREA I Three of the four Borden Delta members in BA-I were deposited during the lowstand systems tract of the Vanceburg Sequence (Richardson, 2003). These deposits, in ascending stratigraphic order, are the Farmers Member (including the Henley Bed), the Nancy Member, and the Cowbell Member of the Borden Formation, which were all transported to the basin as a result of the Osagean forced regression (Richardson, 2003). The youngest and stratigraphically highest member of the Borden succession in BA-I, the Nada Member, was deposited during the transgressive systems tract of the Vanceburg Sequence
Eighty-four miospore samples were collected from the Borden Formation in BA-I, and yielded a high-abundance, high-diversity miospore assemblage. The miospores were recovered from the Farmers Member, the Nancy Member, and the Cowbell Member. The Nada Member, the youngest member of the Borden in BA-I, yielded only amorphous organic matter. Text-Figure 3 shows the spacing of the sample intervals and some of the important taxa throughout the succession located at the Griffen Hollow section in BAI, which is the most complete and longest ranging section in this part of the study area. (A detailed description of the Griffen Hollow section can be seen in Appendix A, locale 1). The miospore assemblage in BA-I is representative of the PC (pretiosus–clavata) Biozone of Western Europe (Higgs et al., 1988; Higgs, 1996). The zone-defining species, Spelaeotriletes pretiosus, is present throughout the succession, but is not the most dominant species. Throughout the entire succession in BA-I, the microfloral assemblage is dominated by Punctatisporites and Retusotriletes, including P. minitus, R. famenensis, and R. planus. Other common taxa include Calamospora, Neoraistrickia, Vallatisporites, Verrucosisporites, Umbonatisporites, and Grandispora. Discernisporites micromanifestus and Geminospora spongiata are present in a somewhat lesser abundance, primarily in the lower part of the succession. The PC (pretiosus– clavata) Biozone is the oldest Osagean biozone and was first described by Clayton et al. (1978). In Western Europe, the base of the PC Biozone lies just below the base of the Polygnathus communis carina Conodont Zone (Clayton et al., 1978). Clayton et al. (1978) recognized that the base of the PC Biozone is just below the disappearance of the siphonodellid conodonts. Therefore, the base of the PC Biozone occurs within the upper part of Tn2, which is an informal Belgian unit. (Throughout the remainder of this report, the units Tn2, Tn3b, Tn3c refer to the informal Belgian stratigraphic units). Higgs (1996) discussed the miospore biostratigraphy of six boreholes from the West Flanders Region of Belgium, where it was proposed that the PC Biozone does not extend upward into the Upper Tournaisian (Tn3). However, the sections studied in this report indicate that the upper part of the PC Biozone is equivalent to part of the Tn3. We propose
SERIES
SERIES (North America)
SYSTEM
J.G. Richardson, W.I. Ausich: Miospore biostratigraphy of the Lower Mississippian in Kentucky and Indiana, U.S.A.
BA-III (North-central KY & SE IND)
161
BA-I (Northeastern Kentucky)
BA-II (South-central Kentucky)
E
W
Visean
Edwardsville Formation Spickert Knob Formation
Fort Payne Formation Muldraugh Member
New Providence Shale
Osagean
“Maury Shale”
“Maury Shale” “Maury Shale”
Borden Formation
Nancy Member
Tournaisian
MISSISSIPPIAN
Kenwood Siltstone
Nada Member Cowbell Member
Nancy Member Farmers Member
Text-Figure 2. Composite diagram showing the general stratigraphic relations of the rocks in Borden Areas I, II, and III. The areas containing vertical lines in BA-I and the eastern part of BA-II represent rocks that were not part of this study.
that the upper boundary of the PC Biozone correlates with the Tn3b–Tn3c boundary based on the miospores and the conodonts recovered from BA-I (Sandberg and Mason, 2002). According to Sandberg and Mason (2002), the Nancy Member in this succession contains the Cave Lake ammonoid fauna, composed of Kazakhstania colubrella, Muensteroceras owenii, and “Karagandoceras” sp., which are correlative with the Upper typicus Zone and the PC Biozone. Thus, the ammonoid fauna confirms the Tn3b (Osagean) age. Based on the conodonts, the Kinderhookian–Osagean boundary, which correlates with the disappearance of the siphonodellid conodonts, (S. isosticha–G. typicus boundary) is located within the upper part of the Henley Bed (basal Farmers Member) (Sandberg and Mason, 2002). The disappearance of the siphonodellids marks the base of the Gnathodus typicus Conodont Zone and is coeval with the base of the Osagean Series. Coleman (1991) reported the first appearance of Spelaeotriletes pretiosus in the upper 1.0 m of the Henley Bed, marking the base of the PC Biozone. This study reports the first appearance of S. pretiosus only slightly higher stratigraphically. Therefore, the lower part of the Henley Bed, below the first appearance of S. pretiosus (Coleman, 1991), may be representative of
the lower part of the Tn3 (Kinderhookian) and the Tn2 (Kinderhookian). Miospores were absent in the Nada Member at all localities sampled. Work and Mason (2003) reported that ammonoids from the Nada Member in the same area as BA-I (this study) are correlative with the Fascipericyclus– Ammonellipsites Zone of Riley (1990). The occurrence of Polaricyclus makes the maximum age of the Nada Member equivalent to the lower Keokuk Limestone of the Mississippi Valley, which is latest earliest Visean. This ammonoid-based age fits in with the age assigned to the beds immediately below the Nada Member; however, using crinoids, Lane and DuBar (1983) and Li (2000) reported these strata to be equivalent to the upper part of the Burlington Limestone (middle to late Tournaisian; middle to late Osagean).
BORDEN AREA II Samples from BA-II were collected from outcrops in south-central Kentucky, including the Pulaski County State Park section, the outcrop of “Maury Shale” along State Route 61 near Burkesville (KY), and numerous outcrops of
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Spelaeotriletes pretiosus
Henley Bed
Retusotriletes famenensis
Farmers Member
Grandispora echinata
Umbonatisporites abstrusus
Neoraistrickia logani
Nancy Member
Spinozonotriletes uncatus
Cowbell Member
Punctatisporites minitus
Early Osagean
Nada Member
Kinderhookian
PC Biozone
Tournaisian
MISSISSIPPIAN
CM Biozone
PALYNOLOGY, VOLUME 28 — 2004
Text-Figure 3. Important miospore taxa in the Borden Formation exposed at Griffen Hollow, northeastern Kentucky (BA-I). The miospores are representative of the PC (pretiosus–clavata) Biozone. Each black dot represents a sampled interval throughout the succession and the black dashes indicate a species occurrence at the given interval.
the Fort Payne Formation along the shores of Lake Cumberland. The Borden Delta rocks in BA-II are representative of two third-order sequences, the distal deposits of the Vanceburg Sequence and the Cumberland Sequence (Richardson, 2003). The lower sequence boundary of both sequences is a correlative conformity, located within the “Maury Shale.” This condensed section (Maury Shale) is composed of tan to gray argillaceous mudstone containing phosphatic nodules and is thought to represent approximately 17 million years of deposition, representing the Kinderhookian and the lower part of the Osagean (Leslie et al., 1996). In the eastern part of BA-II, the “Maury Shale” is overlain by the Nancy Member and the Muldraugh Formation (Text-Figure 2). The Nancy Member is the most distal deltaic deposit in the BA-II region and represents the final stages of the lowstand systems tract of the Vanceburg Sequence (Richardson, 2003). The Nancy Member in this part of BA-II is composed of gray, mud-rich, argillaceous shale with thin continuous silt-dominated turbidites. In the western part of BA-II, the “Maury Shale” is overlain by the Fort Payne Formation, which represents part of the lowstand and the transgressive systems tracts of the Cumberland Sequence (Richardson, 2003). The Fort Payne Formation is represented by a mixed siliciclastic and carbonate succession that locally contains chert deposits, silty limestones, and fine siltstones. In the lower part of the section, the Fort Payne Formation contains carbonate mudmounds and crinoidal packstone build-ups. The shallowwater equivalent of the Fort Payne Formation is the Muldraugh Member, which represents the highstand systems tract of the Cumberland Sequence and is present in the eastern part of BA-II overlying the Nancy Member (Richardson, 2003) (Text-Figure 2).
PLATE 1 All miospore photographs contain a 10 µm scale bar. 1 2 3
4 5 6
Calamospora liquida, 50 µm, specimen recovered from Nancy Member, OSU 51726, 99JR6-1. Calamospora microrugosa, 39 µm, specimen recovered from Nancy Member, OSU 51727, 99JR6-3. Plicatispora quasilabrata, 52 µm, specimen recovered from Spickert Knob Formation, OSU 51728, 00JR14-1. Punctatisporites minitus, 31 µm, specimen recovered from Farmers Member, OSU 51729, 99JR1-6. Punctatisporites minitus, 38 µm, specimen recovered from the Nancy Member, OSU 51730, 99JR6-1. Retusotriletes sp. cf. coniferus, 41 µm, specimen recovered from the Farmers Member, OSU 51734, 99JR1-4.
7 8 9 10 11 12
Raistrickia clavata, 50 µm, specimen recovered from the Farmers Member, OSU 51743, 99JR1-5. Raistrickia condylosa, 54 µm, specimen recovered from Nancy Member, OSU 51747, 99JR6-1. Schopfites claviger, 48 µm, specimen recovered from the New Providence Shale, OSU 51750, 99JR12-1. Umbonatisporites distinctus, 56 µm, specimen recovered from the Farmers Member, OSU 51753, 99JR1-5. Verrucosisporites nitidus, 41 µm, specimen recovered from the Nancy Member, OSU 51758, 99JR6-2. Verrucosisporites nitidus, 44 µm, specimen recovered from the Farmers Member, OSU 51577, 99JR1-7.
J.G. Richardson, W.I. Ausich: Miospore biostratigraphy of the Lower Mississippian in Kentucky and Indiana, U.S.A.
1631 Plate
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Miospore biostratigraphy of BA-II “Maury Shale” samples from the Pulaski County State Park yielded a low number of miospores; however; specimens of Spelaeotriletes pretiosus and Vallatisporites were recovered along with a few of prasinophytes. The occurrence of S. pretiosus is biostratigraphically important because it indicates the Kinderhookian–Osagean boundary (and the base of the PC Biozone) is located within the upper 10 cm of the “Maury Shale”. Several specimens of Pterospermella captiana occurred throughout the condensed section. Dorning (1981) used this species, along with Cymatiosphaera rhacomba, as a depth indicator in his study of the Silurian of the Welsh Basin. Similar applications using prasinophyte specimens may be applicable in this case; however, more individual samples need to be collected. The miospore assemblage in the eastern part of BA-II is correlative to the PC and CM Biozones of Western Europe
(Higgs et al., 1988) (Text-Figure 4). Overlying the “Maury Shale” in the eastern part of BA-II is the Nancy Member, which has its best exposure at the stratotype in Pulaski County State Park. The Nancy Member at this locality yielded a diverse and abundant miospore assemblage and is important because it contains the contact between the PC (pretiosus–clavata) Biozone and the CM (claviger– macra) Biozone (Higgs et al., 1988). The assemblage in the lower part of the Nancy Member is very similar to the Nancy Member assemblage in northeastern Kentucky (BA-I), with specimens of Punctatisporites and Retusotriletes dominant. Specimens of Spelaeotriletes pretiosus, Calamospora microrugosa, and Verrucosisporites nitidus are also common. In sample 00JR8-6, which is located approximately 22 m above the “Maury Shale”–Nancy Member contact, Schopfites claviger was identified. The first appearance of Schopfites claviger marks the base of the CM (claviger–macra) Biozone. The base of the CM Biozone is coeval with the
Plicatispora quasilabrata Vallatisporites vallatus
Bacaudispora fusticulus
Punctatisporites minitus Schopfites claviger
Retusotriletes planus
Spelaeotriletes pretiosus
CM Biozone
Visean Muldraugh Member
Middle
Tournaisian Nancy “Maury Member Shale”
Kinderhookian
PC Biozone
Late
?
Early
MISSISSIPPIAN Osagean
East
Text-Figure 4. Important miospore taxa in the section exposed at Pulaski County State Park, near Nancy, Kentucky. The first occurrence of Schopfites claviger (within the Nancy Member, sample 00JR8-6) marks the base of the CM (claviger–macra) Biozone. Each black dot represents a sampled interval in the succession and the black dashes indicate a species occurrence at the given interval.
J.G. Richardson, W.I. Ausich: Miospore biostratigraphy of the Lower Mississippian in Kentucky and Indiana, U.S.A.
base of the Tn3c (informal Belgian unit) of the Upper Tournaisian and was originally described by Neves et al. (1972) from the Midland Valley of Scotland. Since the original definition of the base in 1972, several species characteristic of the CM Biozone were found to extend downward into the PC Biozone, leading Clayton et al. (1978) to redefine the base stratigraphically lower. In south-central Kentucky, many species from the PC Biozone are also common to the CM Biozone; however, several species that make their first appearance include Schopfites claviger, Baculatisporites fusticulus, and Plicatispora quasilabrata (Text-Figure 4). Because the Nancy Member in south-central Kentucky straddles the PC Biozone-CM Biozone boundary, it is slightly younger than the Borden Delta deposits (with the exception of the Nada Member) in BA-I. The Nada Member in BA-I may have been operating as the delta top while active Nancy Member deposition was going on in BA-II. With the assignment of the CM Biozone and the Tn3c interval, the Nancy Member in the eastern part of BA-II is correlative to the middle to upper part of the Burlington Limestone in the reference sections in the Mississippi Valley (middle to late Osagean). In the western part of BA-II, the miospore biostratigraphy is not clearly defined. The “Maury Shale” in the western part of BA-II, especially near Burkesville (Kentucky), yielded some miospores; however, none were biostratigraphically significant. Above the “Maury Shale” in the western part of BA-II is the Fort Payne Formation. The Fort Payne Formation is composed of several different lithologies but can generally be described as a mixed siliciclastic and carbonate unit containing chert and thin siltstones, with mudmounds and crinoidal packstones within the base of the section (Ausich and Meyer, 1990; Meyer et al., 1989). The Fort Payne Formation was sampled at multiple intervals across several localities within the western part of BA-II. No biostratigraphically significant miospores were recovered. The low-diversity, low-abundance assemblage contained mostly specimens of Convolutispora vermiformis and specimens of Knoxisporites sp. Specimens of Rotaspora fracta may have been recovered; however, most of the specimens were crushed or thermally altered and could not be positively identified. All of the samples from the Fort Payne Formation also contained a high percentage of amorphous organic matter. Hororwitz et al. (1979) reported the occurrence of Lycospora pusilla from a cored section of the Fort Payne Formation in Scott County, Tennessee. The occurrence of L. pusilla in Tennessee makes the Fort Payne at that core location at least upper Tournaisian (late Osagean) in age. Using conodonts, Ruppel (1979) concluded the Fort Payne
165
Formation of Northern Alabama coincides with the Gnathodus texanus–Taphrognathus Zone, which is equivalent to the Keokuk Limestone in the Mississippi Valley. Ausich and Meyer (1990) reported Gnathodus texanus from crinoid-bearing facies and late Osagean crinoids. Combining the low number of miospores from the Fort Payne Formation in BA-II with the Horowitz et al. (1979) data, the authors can confirm, with confidence, the age of the Fort Payne Formation in south-central Kentucky is at least late Tournaisian (late Osagean).
BORDEN AREA III The rocks sampled in Borden Area III are located in north-central Kentucky, southeastern and south-central Indiana (Louisville to Bloomington). The Borden rocks in this part of the study area represent parts of two third-order depositional sequences (Richardson, 2003). The older of the two, the New Providence Sequence, is bound at the base by a correlative conformity found within the “Maury Shale” equivalent. This “Maury Shale” is a glauconite-rich, brown, argillaceous mudstone, approximately 30 cm thick, and is at the base of the New Providence Shale in south-central Indiana. The New Providence Sequence is represented by only the transgressive systems tract, the New Providence Shale (Richardson, 2003; Ahmad, 2000). Overlying the New Providence Sequence is the youngest sequence in the study, the Millport Knob Sequence. This sequence is named for the extensive exposure of most of the sequence at Millport Knob in south-central Indiana. The Millport Knob Sequence contains a lowstand systems tract (Kenwood Siltstone), a transgressive systems tract (Spickert Knob Formation), and a highstand systems tract (Edwardsville Formation) (Text-Figure 2).
Miospore biostratigraphy of BA-III In BA-I and BA-II, the Borden rocks have been correlative with previously established miospores zones of Western Europe (Higgs et al., 1988; Higgs, 1996). Borden Area III however, represents a part of the study area where the miospore biostratigraphy and intercontinental relations becomes somewhat more difficult to decipher. The oldest member of the Borden Delta in BA-III is the New Providence Shale, which is underlain by the condensed section of the “Maury Shale.” The age of the New Providence Shale has been a topic of much debate since the original description by Borden (1874). Springer (1911), Conkin (1957), Rexroad and Scott (1964), and Kammer (1985) have all proposed different ages for the New Providence Shale,
166
Locust Point Member
Cristatisporites menendezii
Baculatisporites fusticulus
Schopfites claviger
Lycospora pusilla
Carwood Member
Spickert Knob Formation
Kenwood Sts
New Providence Shale
Tumulispora sp. B
Osagean
Floyds Knob Bed
Vallatisporites vallatus
Edwardsville Formation
Pu Biozone
Tricidarisporites sp. A –Dictylotriletes sp. B
Tumulispora sp. B S. claviger Assemblage
Late Tournaisian-Early Visean ?
MISSISSIPPIAN
PALYNOLOGY, VOLUME 28 — 2004
Text-Figure 5. Composite diagram showing important miospore taxa and their distribution within the New Providence Shale at the Brooks Stone Quarry, the Kenwood Siltstone at Finley Hill, and the excellent exposure at Millport Knob in south-central Indiana. First occurrence data defines the assemblages and the biozone occurring in this interval. Each black dot represents a sampled interval in the succession and the black dashes indicate a species occurrence at the given interval.
PLATE 2 All miospore photographs contain a 10 µm scale bar. 1 2
3 4 5 6 7
Verrucosisporites nitidus, 40µm, specimen recovered from the Cowbell Member, OSU 51755, 01JR2-4. Convolutispora caliginosa, 55 µm, specimen recovered from the Spickert Knob Formation, OSU 51759, 00JR14-6. Auroraspora macra, 41 µm, specimen recovered from the Nancy Member, OSU 51768, 99JR6-3. Grandispora corunata, 41 µm, specimen recovered from the Nancy Member, OSU 51772, 99JR6-3. Spelaeotriletes pretiosus, 61 µm, specimen recovered from the Nancy Member, OSU 51776, 99JR6-2. Spelaeotriletes pretiosus, 48 µm, specimen recovered from the Cowbell Member, OSI 51777, 01JR2-4. Spinozonotriletes uncatus, 70 µm, specimen recovered from the Nancy Member, OSU 51780, 00JR6-1.
8 9
10
11
12
Spinozonotriletes uncatus, 69 µm, specimen recovered from the Nancy Member, OSU 51781, 99JR6-3. Cristatisporites menendezii, 65 µm, specimen recovered from the Spickert Knob Formation, OSU 51783, 00JR14-5. Vallatisporites microspinosus, 45 µm, specimen recovered from Spickert Knob Formation, OSU 51787, 00JR14-2. Vallatisporites vallatus, 68 µm, specimen recovered from the Spickert Knob Formation, OSU 51789, 00JR14-1. Lycospora pusilla, 41 µm, specimen recovered from the Edwardsville Formation, OSU 51794, 00JR14-9.
J.G. Richardson, W.I. Ausich: Miospore biostratigraphy of the Lower Mississippian in Kentucky and Indiana, U.S.A.
167 Plate 2
168
ranging from the middle Tournaisian to the early Visean, based on crinoids, brachiopods, and conodonts. The New Providence Shale in north-central Kentucky and southeastern Indiana yielded a fairly low-abundance miospore assemblage (Text-Figure 5). The lowest samples of the New Providence Shale contain Schopfites claviger, which, as discussed previously, is an index fossil for the CM (claviger–macra) Biozone in Western Europe. Schopfites claviger has a shorter range in Europe (upper Tournaisian to middle Visean) than in North America (upper Tournaisian to lower Namurian) (Neves and Belt, 1970). The miospore assemblage of the New Providence Shale also contains specimens of Calamospora microrugosa, Cristatisporites menendezii, Grandispora corunata, and several species of Vallatisporites. Schopfites claviger disappears in the upper part of the New Providence Shale and does not reappear until higher in the section (Spickert Knob Formation). The Kenwood Siltstone is stratigraphically above the New Providence Shale in BA-III and was sampled for palynomorphs; however, the samples were not productive (Text-Figure 5). This is probably due to the relatively large grain size of the Kenwood Siltstone. The Kenwood Siltstone was described as a submarine valley fill deposit by Kepferle (1977); however, new sedimentological and sequence stratigraphical evidence indicate the Kenwood Siltstone is indicative of deposition at the mouth of a submarine canyon (Richardson, 2003). Although there were no miospores recovered from the Kenwood Siltstone, the unit did yield a high amount of amorphous organic matter and phyto-debris. Stratigraphically above the New Providence Shale and the Kenwood Siltstone is the Spickert Knob Formation. The section exposed at Millport Knob in south-central Indiana exhibits one of the most complete successions of this part of the Borden Delta in BA-III (Rexroad and Lane, 1984). The base of the exposure at Millport Knob is located within the lower part of the Locust Point Member (Spickert Knob Formation). Palynomorph samples were taken at seven intervals throughout the succession (Text-Figure 5). Miospores from samples in the Spickert Knob Formation are abundant and diverse. The miospore assemblage is dominated by species of Vallatisporites, with Punctatisporites minitus, Retusotriletes famenensis, and R. planus also abundant. Schopfites claviger also occurs throughout the section; however, it is not present in all samples. The other zonal species, Auroraspora macra, is also present within the section but is less abundant than S. claviger. The overlying Carwood Member of the Spickert Knob Formation, contains most of the microflora that is present in the lower part of the formation, but the abun-
PALYNOLOGY, VOLUME 28 — 2004
dances of Grandispora and Cristatisporites menendezii increase. Common species in the Spickert Knob Formation at Millport Knob section also include specimens of Spelaeotriletes pretiosus, Baculatisporites fusticulus, Raistrickia corynoges, and Plicatispora quasilabrata. Near the top of the Millport Knob section, the Floyds Knob Bed is well exposed and consists of resistant, silt-rich limestone that is easily distinguishable in outcrop and represents the base of the Edwardsville Formation. The microflora present in the Floyds Knob Bed is similar to the assemblage in the underlying Spickert Knob Formation. The primary difference is that the sample at the base of the Floyds Knob Bed contains several specimens of Lycospora pusilla. The first appearance of L. pusilla marks the base of the Pu (pusilla) Biozone, which correlates with the late Tournaisian in Europe. Although the exact age of the top of the CM Biozone is not known, Phillips and Clayton (1980) assigned the CM–Pu zonal boundary on Clare Island in the west of Ireland, as being slightly below the Tournaisian– Visean boundary. The base of the Visean has been defined by the first appearance of Eoparastaffella simplex in the lineage of E. ovalis–E. simplex. This foram has not been identified in this part of North America, so correlations may be difficult (Sevastopulo et al., 2002; Devuyst et al., 2003). At Millport Knob, the Edwardsville Formation contains a diverse and abundant assemblage including species of Calamospora, Punctatisporites, Baculatisporites, Lycospora, and Gorgoniospora. Very productive samples from the upper part of the Spickert Knob Formation were also taken from Indiana Route 211, located 15 km south of New Albany, Indiana. At this locality, the upper part of the Spickert Knob (Carwood Member) Formation yielded specimens of Cristatisporites, Grandispora, Granulatisporites, Retusotriletes, Vallatisporites, and Verrucosisporites. The sporadic occurrences of S. claviger throughout the section at Millport Knob make a correlation with the CM Biozone of Western Europe difficult. Based on the Millport Knob spores, the Spickert Knob Formation is at least Tn3c; however, it is probably much younger, based on other fossil groups (Ausich and Lane, 1980; Kammer, 1985). The first occurrence of Lycospora pusilla in the Floyds Knob Bed demonstrates at least a late Tournaisian age, representative of the Pu Biozone in Western Europe (Higgs et al., 1988). The first occurrence of L. pusilla in the Floyds Knob Bed (Edwardsville Formation) demonstrates the dynamic nature of the Borden Delta rocks in Indiana. As discussed above, the New Providence Shale in northern Kentucky– southeastern Indiana has been assigned a lower Keokuk Limestone-equivalent age (Visean), but it is stratigraphically much lower in the Borden succession.
J.G. Richardson, W.I. Ausich: Miospore biostratigraphy of the Lower Mississippian in Kentucky and Indiana, U.S.A.
Coleman (1991) defined three assemblages for the Borden Delta succession in Indiana. According to her, the S. claviger Assemblage encompasses the lower part of the New Providence Shale; the Tumulispora sp. B Assemblage includes the rocks of the upper New Providence Shale and the lower part of the Spickert Knob Formation, and the Tricidarisporites sp. A–Dictylotriletes sp. B Assemblage for the rocks of the upper Spickert Knob and Edwardsville formations. Each of these miospore assemblages is based on first occurrence data. In the lower part of the Indiana section (S. claviger Assemblage), S. claviger is prominent. Stratigraphically higher in the New Providence Shale, S. claviger disappears and did not reappear in her samples. Samples in the present study contain specimens of Schopfites claviger within the upper part of the Spickert Knob Formation, whereas we do not completely agree with some of the ranges for some of the zone taxa, the first occurrence data is correlative, therefore the three assemblages assigned by Coleman (1991) will be used here; but are slightly modified. The slight modification occurs with the addition of the Pu Biozone near the top of the Borden Delta in Indiana, within the Edwardsville Formation. Coleman (1991) proposed that the Tricidarisporites sp. A–Dictylotriletes sp. B Assemblage begins with the first occurrence of the zone taxa, correlative with the base of the Carwood Member (upper member of Spickert Knob Formation) and extends to the top of the Edwardsville Formation, the youngest rocks in the study. We propose instead, that the base of the Floyds Knob Bed defines the base of the Pu Biozone, which according to biozones in Europe, are at least late Tournaisian, but probably Visean. Although the exact stratigraphic relationship between the two sections is not coeval, the age of both is definitely Visean. There are several possibilities for the discrepancy in this correlation. The absence of not only index taxa, but a slightly different assemblage composition suggests there might have been terrestrial provincialism during the Early Mississippian. It could also signify the miospores represent a slightly different floral assemblage. Although the Borden Delta in the eastern and south-central part of the study area were draining the Acadian Highlands in the east, it is possible the Borden Delta in the western part of the study area were draining a part of the Canadian Shield. It is also possible that the sedimentology and eustatic behavior was a factor in sediment and miospore dispersal. The exact reason for this change in the miospore assemblage will need further study.
STRATIGRAPHIC SUMMARY The rocks of the Borden Delta across the study area contain a highly-diverse and highly-abundant miospore
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flora. The biostratigraphic relations of all the units reported here are shown in Text-Figure 6. The rocks in northeastern Kentucky contain a characteristic miospore assemblage of the PC Biozone. The PC Biozone is coeval with the Gnathodus typicus and Polygnathus communis corina (European) conodont zones (Jones, 1996). Therefore, Borden Delta rocks in northeastern Kentucky are at least Tn3b equivalent, or middle Burlington (early Osagean). The eastern part of south-central Kentucky, primarily the thick exposure in Pulaski County State Park, contains the boundary between the PC Biozone and the CM Biozone. This boundary coincides with the boundary between the Tn3b–Tn3c, with the CM Biozone being strictly Tn3c. These uppermost Tournaisian rocks are coeval with the anchorlais–latus Conodont Zone, and the upper Burlington Limestone of the Mississippian Valley (early to middle Osagean). The western part of south-central Kentucky is dominated by the Fort Payne Formation, which is equivalent to the Keokuk Limestone in the Mississippi Valley sections (early Visean); however the base, referred to in the text as the “Maury Shale”, represents the Kinderhookian and the lower part of the Osagean, mostly Burlington equivalents. The exposures in north-central Kentucky and southeastern Indiana contain the youngest rocks in the study area. The basal deposits of the Borden Delta in this area are represented by the New Providence Shale. The lower part of the New Providence Shale is partially correlative with the CM Biozone; however, Schopfites claviger is not consistent throughout the succession. The upper part of the New Providence Shale does not contain any specimens of S. claviger. Specimens of S. claviger reappear in the Spickert Knob Formation, making it at least Tn3c, or uppermost Tournaisian. However, because miospores in this part of the study area do not match the miospore zones of western Europe, which define the Tournaisian–Visean boundary palynologically, and the fact that most other faunal groups indicate an age of Visean for the New Providence Shale, the authors agree on an age of Visean for the New Providence Shale in BA-III in north-central Kentucky. Likewise, the Spickert Knob Formation miospore assemblage does not correlate with the previously established miospore biozones; however, specimens of S. claviger appear at several intervals throughout the lower part of the Spickert Knob Formation. In southern Indiana, the Floyds Knob Bed, stratigraphically above the Spickert Knob Formation, yields the first occurrence of Lycospora pusilla. The first occurrence of L. pusilla assigns a definite age of late Tournaisian, but more than likely Visean (Vn1a). From south to north in BA-III, the interval spanning the succession from the New Providence Shale through the Floyds Knob Bed, needs a detailed multi-faunal and floral biostratigraphic analysis in
N. Amer. Conodont Zones Gnathodus ‘texanus’ Taphrognathus
Miospore Biozones
European Conodont Zones Mestognathus beckmaniGnathodus homopunctatus
Belgian Regional Stages
Moliniacian
Po. communis corina
anchoralislatus Gnathodus typicus
British Isles Regional Stages
Chadian
? Pu Biozone Tri. A–Dic. B
? Ivorian
Tn3c Tn3b
Tournaisian
Burlington
Early
Middle
?
Courceyan
Informal Belgian Units
Vn1
Series
Visean
Miss. Valley Sections
Keokuk
Late
N.A. Series
Subsystem
MISSISSIPPIAN
Osagean
System
PALYNOLOGY, VOLUME 28 — 2004
CARBONIFEROUS
342 ± 3.2Ma
Menning et al., 2000
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Tum. B S. claviger
CM Biozone
U L
PC Biozone
Text-Figure 6. Composite diagram showing the biostratigraphic relations throughout the lower part of the Mississippian. The biostratigraphic data relates to miospores and conodonts, and the absolute age was proposed by Menning et al. (2000).
order to gain a more complete understanding of the dynamics of the facies and age relations in this area. This report of the miospore biostratigraphy from the Borden Delta helps us gain a more complete understanding of the age relationships of the time-transgressive units that were deposited as the delta migrated from east to west across the study area, how they correlate to the Early Mississippian rocks of western Europe, and may give inferences to the floral provincialism during the lower part of the Mississippian.
ACKNOWLEDGMENTS The authors would like to thank Drs. G. Clayton (Trinity College), M. R. Saltzman, L. A. Krissek, and S. R. Jacobson of The Ohio State University for correspondence on stratigraphic and palynologic issues. Special thanks are extended to E. R. Slucher at the Ohio Geologic Survey for stratigraphic suggestions and discussions and to Dr. R. Askin for use of the palynology laboratory facilites and her endless hours of help. Finally, the authors would like to thank the reviewers of this report for their critiques and suggestions.
References Cited AHMAD, N. 2000 Deposition, sequence stratigraphy, and hydrocarbon potential of a gravity flow deposit (Carper Sandstone) within the Osagean (Middle Mississippian) sequence stratigraphic framework, eastern Illinois Basin. Unpublished Ph.D. thesis. Indiana University, 455 p. AUSICH, W.I. 1983 Component concept for the study of paleocommunities with an example from the early Carboniferous of southern Indiana (U.S.A.). Palaeogeography, Palaeoclimatology, Palaeoecology, 44: 251–282. AUSICH, W.I., KAMMER, T.W., and LANE, N.G. 1979 Fossil communities of the Borden (Mississippian) Delta in Indiana and northern Kentucky. Journal of Paleontology, 53: 1182–1196. AUSICH, W.I., AND LANE, N.G. 1980 Platform communities and rocks of the Borden siltstone delta (Mississippian) along the south shore of Monroe Reservoir, Monroe County, Indiana. In: Shaver, R.H., (ed.), Field trips from the Indiana University Campus, Bloomington, Indiana University, Bloomington, p. 37–67.
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AUSICH, W.I., and MEYER, D.L. 1990 Origin and composition of carbonate buildups and associated facies in the Ft. Payne Formation (Lower Mississippian, south-central Kentucky): An integrated sedimentologic and paleoecologic analysis. Geological Society of America Bulletin, 102: 129–146. BORDEN, W.W. 1874 Report of a geological survey of Clarke and Floyd Counties, Indiana. Indiana Geological Survey, 5th Annual Report: 134–189. BRYAN, T.M. 1983 Depositional history provides clues: Understanding the geologic makeup of the Farmers Member may help exploration target selection in deltaic sands. Northeast Oil Reporter, December: 43–46. CHAPLIN, J.R. 1980 Stratigraphy, trace fossil associations, and depositional environments in the Borden Formation (Mississippian) north-eastern Kentucky. Guidebook for Annual Field Conference of the Geological Society of Kentucky, Lexington, Kentucky Geological Survey: 114 p. CLAYTON, G., HIGGS, K., KEEGAN, J.B., and SEVASTOPULO, G.D. 1978 Correlation of the palynological zonation of the Dinantian of the British Isles. Palinologia, 1: 137– 147. COLEMAN, U. 1991 Palynology and intercontinental correlation of Upper Devonian and Lower Mississippian rocks from Kentucky and Indiana, U.S.A. Unpublished Ph.D. thesis, University of Dublin, 435 p. COLEMAN, U., and CLAYTON, G. 1987 Palynostratigraphy and palynofacies of the uppermost Devonian and Lower Mississippian of eastern Kentucky (U.S.A.), and correlation with western Europe. Courier Forschungsinstitut Senckenberg, 98: 75–93. CONKIN, J.E. 1957 Mississippian small foraminifera of the eastern United States. Geological Society of America Bulletin, 68(12): 1889. DORNING, K.J. 1981 Silurian acritarch distribution in the Ludlovian shelf sea of south South Wales and the Welsh Borderland. In: Neale, J.W., and Brasier, M.D., Microfossils from recent and fossil shelf seas. Ellis Harwood Ltd., Chichester: 31–36. DEVUYST, F.X., HANCE, L., HOU, H., TIAN, S., COEN, M., and SEVASTOPULO, G. 2003 A proposed Global Stratotype Section and Point for the base of the Visean Stage (Carboniferous): the Pengchong section, Guangxi, South China. Episodes, 26(2): 105–115. GUTSCHICK, R.C., and SANDBERG, C.A. 1983 Mississippian continental margins of the conterminous United States. SEPM Special Publication, 33: 79–96.
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HIGGS, K. 1996 Taxonomy and systematic study of some Tournaisian (Hastarian) spores from Belgium. Review of Palaeobotany and Palynology, 93: 269–297. HIGGS, K., CLAYTON, G., and KEEGAN, J.B. 1988 Stratigraphic and systematic palynology of the Tournaisian of Ireland. Special Paper, Geological Survey of Ireland, 7: 1–82. HOROWITZ, A.S., MAMET, B.L., NEVES, R., POTTER, P.E., and REXROAD, C.B. 1979 Carboniferous paleontological zonation and intercontinental correlation of the Fowler no. 1, Traders Core, Scott County, Tennessee, U.S.A. Southeastern Geology, 20: 205–228. JONES, P.J. 1996 Carboniferous (Chart 5). In: Young, G.C., Laurie, J.R., (eds.), Australian Phanerozoic Timescale. Oxford University Press, Melbourne; New York, p. 110–126. KAMMER, T.W. 1985 Basinal and prodeltaic communities of the Early Carboniferous Borden Formation in northern Kentucky and southern Indiana (U.S.A.). Paleogeography, Paleoclimatology, Paleoecology, 49: 79–121. KEPFERLE, R.C. 1977 Stratigraphy, petrology, and depositional environment of the Kenwood Siltstone Member, Borden Formation (Mississippian), Kentucky and Indiana. U.S. Geological Survey Professional Paper 1007: 49 p. LANE, N.G. 1973 Paleontology and paleoecology of Crawfordsville fossil site (Upper Osagian: Indiana). University of California Publications in Geological Sciences, 99: 141 p. LANE, N.G., and DU BAR, J.R. 1983 Progradation of the Borden Delta: new evidence from crinoids. Journal of Paleontology, 57: 112–123. LESLIE, S.A., AUSICH, W.I., and MEYER, D.L. 1996 Lower Mississippian sedimentation dynamics and conodont biostratigraphy (Lowermost Fort Payne Formation) along the southeastern margin of the eastern interior seaway. Southeastern Geology, 36(1): 27–35. LI, A. 2000 Paleontology and paleoecology of the Nada Member of the Borden Formation (Lower Mississippian) in eastern Kentucky. Unpublished Ph.D. thesis. The Ohio State University, Columbus, Ohio, U.S.A., 186 p. LITWIN, R.J., and TRAVERSE, A. 1989 Basic guidelines for palynomorphs extraction and preparation from sedimentary rocks. In: Feldman, R.M., Chapman, R.E., and Hannibal, J.T., (eds.), Paleo-techniques. Paleontological Society Special Publication, 4: 87–98. MASON, C.E. 1981 Early Mississippian ammonoids from the lower part of the Borden Formation, northeastern Kentucky.
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Unpublished M.S. thesis, George Washington University, Washington, D.C., 129 p. MATCHEN, D.L. and KAMMER, T.W. 1994 Sequence stratigraphy of the Lower Mississippian Price and Borden Formations in southern West Virginia and eastern Kentucky. Southeastern Geology, 34(1): 25–41. MENNING, M., DRODZEWSKI, G., WENDT, I., WEYER, D., and VAN AMERON, H.W.J. 2000 A Carboniferous time-scale 2000; discussion and use of geologic parameters as time indicators from central and western Europe. Geologisches Jahrbuch, Reiche A: Allgemeine und Regionale Geologie Deutschland und Nachbargebiete, Tektonik, Stratigraphie, Palaeontologie, v. 156: 3–44. MEYER, D.L., AUSICH, W.I., and TERRY, R.E. 1989 Comparative taphonomy of echinoderms in carbonate facies: Fort Payne Formation. Palaois, v. 4, no. 6: 533–552. NEVES, R., and BELT, E.S. 1970 Some observations on Namurian and Visean spores from Nova Scotia, Britain, and northern Spain. Compte Rendu, 6 ème, Congrès International de Stratigraphie et de Geologie du Carbonifère (Sheffield 1967), 3: 1233–1249. NEVES, R., GUEINN, K.J., CLAYTON, G., IONNIDES, N.S., NEVILLE, R.S.W. 1972 A scheme of miospore zones for the British Dinantian. 6th International Congress of Carboniferous Stratigraphy and Geology, Compte Rendu, v. 7: 347–353. PHILLIPS, W.E.A., and CLAYTON, G. 1980 The Dinantian clastic succession on Clare Island, County Mayo. Royal Irish Academy, Journal of Earth Sciences (Dublin), v. 2, no. 2: 115–135. REXROAD, C.B., and LANE, N.G. 1984 Spickert Knob Formation (new), Borden Group, in Indiana. Department of Natural Resources, Geological Survey Paper 43. REXROAD, C.B., and SCOTT, A.J. 1964 Conodont zones in the Rockford Limestone and lower part of the New Providence Shale (Mississippian) in Indiana. Indiana Geological Survey Bulletin 30: 54 p. RICHARDSON, J.G. 2003 Miospore biostratigraphy, sequence stratigraphy, and glacio-eustatic response of the Borden Delta (Osagean; Tournaisian–Visean) of Kentucky and Indiana, U.S.A. Unpublished Ph.D. thesis, The Ohio State University: 275 p. RILEY, N.J. 1990 A global review of mid-Dinantian ammonoid biostratigraphy; In: P. Brenkle and W. M. Manger (eds.), Intercontinental correlation and division of the Carboniferous System. Courier Forschunginstitut Senckenberg, v. 130: 133–144.
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RUPPEL, S.C. 1979 Conodonts from the Lower Mississippian Fort Payne and Tuscumbia Formations of northern Alabama. Journal of Paleontology, v. 53, no. 1: 55–70. SANDBERG, C.A., and MASON, C.E. 2002 Position of Kinderhookian–Osagean boundary in northeastern Kentucky and southern Ohio. Abstracts with Programs, Geological Society of America, 36th Annual North-Central and 51st Annual Southeastern Sections, Joint Meeting, Lexington, Kentucky. [abstract] SEVATOPULO, G., DEVUYST, F.X., HANCE, L., HOU, H., COEN, M., CLAYTON, G., TIAN, S., and HU, X.H. 2002 Progress report of the Working Group to establish a boundary close to the existing Tournaisian–Visean boundary within the Lower Carboniferous. Carboniferous Newsletter, v. 20: 6–7. SPRINGER, F. 1911 The crinoid fauna of the Knobstone Formation. Proceedings of the United States National Museum, 41: 175–208. WORK, D.M., and MASON, C.E. 2003 Mississippian (middle Osagean) ammonoids from the Nada Member of the Borden Formation, Kentucky. Journal of Paleontology, v. 77: 593–596.
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APPENDIX A Appendix A includes descriptions of four of the more important outcrops sampled. Each location includes general location information, along with a detailed description.
Locale 1 Griffen Hollow Section This succession exposes a nearly complete succession of the Borden Delta sediments, including the Farmers Member, Nancy Member, and the Cowbell Member. The exposure is located approximately 5.0 km east of Vanceburg, Kentucky along State Route 546. Farmers Member — 0–41.2 m Siltstone, fine to medium grained, tabular and continuous, interbedded with thinly bedded, pelagic-shales. Siltstone layers are turbiditic in origin. Each turbidite has a sharp basal contact, and a bioturbated top. Vertical burrows present throughout, some burrows penetrate the entire bed, some do not. Turbidites vary inthickness from 0.5 m to greater than 7.0 m. Nancy Member — 41.2–61.7 m Silty shale, gray to greenish gray, interbedded with thinly bedded, continuous siltstone layers of turbiditic origin. Each turbidite has a sharp basal contact and bioturbated tops. Sideritic concretions throughout the silty shale, more abundant basally. Cowbell Member — 61.7–79.7 m Siltstone, gray to bluish-gray, resistant with massive appearance.Bioturbation throughout, cross-bedding throughout but not prominent. Fossils rare but present, and iron concretions presentthroughout.
Locale 2 Pulaski County State Park The section measured in Pulaski County State Park is the stratotype of the Nancy Member. This exposure is located primarily along the east side on the road; however, the base of the section can be seen in the small valley along the west side of the road. At the base of the section is the Devonian Chattanooga Shale, which is overlain by a thin exposure of the Maury Shale, the Nancy Member, and topped by an exposure of the Muldraugh Member. Chattanooga Shale — 0–1.5 m Shale, black, fissile and thinly bedded. Pyrite staining throughout the succession. Poorly fossiliferous.
“Maury Shale” — 1.5–1.8 m Shale, tan to gray, argillaceous, and poorly consolidated.Glauconite present throughout but more abundant towards the top. Nancy Member — 1.8–37.2 m Shale, gray to grayish green, poorly consolidated. Interbedded continuous, thinly bedded siltstones, turbiditic in origin. Fossils present throughout, rare in the base and more abundant near the top. Shales and mudstones dominate the basal deposits but grade to silty-shales near the top of the exposure. Turbidites more abundant in the basal deposits. Muldraugh Member — 37.2–42.0 m Silty limestones, brown to light-brown, well consolidated, fossilfragments present, mostly crinoids and bryozoans. Interbedded with discontinuous lenses of siltstone.
Locale 3 Brooks Stone Quarry The exposure at the Brooks Crushed Stone Quarry is an excellent, rare section in that it exposes the base of the New Providence Shale. The main part of the quarry is located on the southwest side of Button Mold Knob. The quarry can be accessed by driving north on State Route 1020 from Shepardsville, Kentucky. New Albany Shale — 0–24.0 m Black, thinly bedded, fissile shale. Base of this unit is not exposed in the quarry, but the upper contact has a sharp contact with the overlying New Providence Shale. “Maury Shale” — 24.0–24.5 m Tan, nodular, glaunconite-rich shale. Condensed section. The unit is observable between the underlying New Albany Shale and the overlying New Providence Shale. This unit represents an area ofmaximum flooding and this quarry is the one of the only placeswhere the base of the New Providence Shale is observable. New Providence Shale — 24.5–45.0 m Gray, fissile, thinly-bedded shale. Poorly fossiliferous; howeversome horizons can be extremely fossiliferous. The shale is more compressed near the bottom of the section and becomes heavilyweathered near the top of the section.
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Locale 4 Millport Knob Section
Covered Interval — 27.0–42.0 m
The section exposed at Millport Knob is located on Indiana State Route 135, just north of Millport, Indiana. The section exposes the Spickert Knob Formation, the Floyds Knob Member, and the Edwardsville Formation. The base of the section is located along the west side of State Route 135, just south of the intersection of Indiana State Route 135 and Delany Port Road. The remainder of the section is located on the east side of the road, on the north side of the intersection.
Spickert Knob Formation Locust Point Member — 0–27.0 m Siltstone, gray to blue-gray, interbedded with thinly bedded shalelenses. Sideritic concretions abundant in the base of the section and the top of the unit, but barren in the middle. Fossils present throughout, but not abundant. Trace fossils, “curly worm marks”, visible throughout the section. Geodes present in the ironstone concretions.
Carwood Member — 42.0–57.8 m Siltstone, gray to bluish-gray, fairly resistant. Interbedded with discontinuous layers of bioclastic debris, wellsorted. Several sedimentary structures present through the unit. Trace fossils, “curly worm marks,” present throughout the section. Floyds Knob Bed — 57.8–59.5 m Dolomite, brown to reddish-brown, fine-grained, resistant.Poorly fossiliferous. Small occurrence of glauconite in the base.This unit represents the first transgressive surface since the sea-level drop at the end of the Kinderhook. Edwardsville Formation — 59.5–76.9 m Siltstone, gray-brown to reddish-brown, soft. Poorly fossiliferous.trace fossils, “curly worm marks,” present. This unit representsThe early stages of the transgressive systems tract.
APPENDIX B Appendix B includes an alphabetical species list of all the species present in this study. The list includes species of miospores, acritarchs, and prasinophytes. Miospores Auroraspora macra Auroraspora solisorta Baculatispories fusticulus Calamospora liquida Calamospora microrugosa Captotriletes prionotus Convolutispora caliginosa Convolutispora vermiformis Cristatisporites menedezii Dictylotriletes trivialis Discernisporites micromanifestus Emphanisporites rotatus Geminospora spongiata Grandispora corunata Grandispora echinata Granulatisporites microgranifer Knoxisporites sp. Krauselisporites mitratus Latosporites sp. Lycospora pusilla Microretuculatisoporites araneum
Neoraistrickia logani Plicatispora quasilabrata Punctatisporites minitus Puncatatisporites planus Raistrickia clavata Raistrickia condylosa Retusotriletes sp. cf. coniferus Retusotriletes famenensis Retusotriletes planus Rotaspora fracta Rugospora flexuosa Schopfites claviger Secarisporites sp. Spelaeotriletes obustus Spelaeotriletes pretiosus Spinozonotriletes uncatus Umbonatisporites abstrusus Umbonatisporites distinctus Vallatisporites microspinosus Vallatisporites vallatus Verrucosisporites gibberosus Verrucosisporites nitidus
Acritarchs Dorsennidium patulum Guttatisphaeridium pandum Micrhystridium erugatum Micrhystridium flexible Solisphaeridium astrum Stellinium inflatum Prasinophytes Cymatiosphaera rhacomba Pterospermella captiana
