Conodont Biostratigraphy and δ13C Chemostratigraphy of the Salina Group (Silurian) in Western Ohio and Eastern Indiana

Master’s Thesis

Presented in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Graduate School of The Ohio State University

By

Robert James Anthony Swift, B.A.

Graduate Program in Geological Sciences

The Ohio State University

2011

Master’s Committee:

Dr. Mark A. Kleffner, Advisor

Dr. William I. Ausich

Dr. Matthew R. Saltzman

Copyright by

Robert James Anthony Swift

2011

Abstract

The Salina Group type area in New York State is well defined, but strata assigned to the Salina Group in Ohio and Indiana may not actually correlate in age or depositional equivalence with the New York units. The integrated tools of bio- and chemostratigraphy, with the well-studied lithostratigraphy, are enabling Paleozoic workers around the world to better constrain regional units in time and space. For the

Wenlock and Ludlow, the Mulde and Lau δ13C excursions can be used as correlative tools. A well developed conodont biozonation has also been applied successfully in

North America.

Four localities were sampled and processed for conodont biostratigraphy and δ13C stratigraphy. Two localities were sampled on the eastern flank of the Cincinnati Arch, one was sampled on the western flank of the Arch, and the fourth was a core drilled in northern Indiana that penetrates the Salina Group some 800 ft underground.

The strata from two Ohio localities contained conodonts that can be used as age indicators. Duff Quarry (Huntsville, Ohio) yielded a fauna comprised of Ozarkodina species of O. confluens affinity and Oulodus species. In each case, comparisons to previous work indicate an age of late Ludlow to early Pridoli. Con Ag Quarry (St.

Mary’s, Ohio) yielded Pseudooneotodus linguicornis, and also the Mulde δ13C excursion in the Greenfield Dolomite, which leads to a conclusive age for the Greenfield Dolomite of Homerian. The Waldron Member of the Pleasant Mills Formation in Indiana contains ii

the Mulde δ13C excursion, as expected due to its stratigraphic position and reports of the

Mulde in the Waldron Member outside Indiana. Salina Group strata in northeastern

Indiana have an age of Homerian and younger, according to the excursion and conodonts from the HA7 Core. This is supported by the positioning of the Mulde excursion within the oldest anhydrite-hosting portion of that core as well as zonal conodonts appearances including Ozarkodina bohemica longa and Ozarkodina snajdri.

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Acknowledgments

My thanks go out to my advisor, Dr. Mark Kleffner, for the assistance and mentoring that introduced me to this project and enabled me to complete it. Dr. Jim

Barrick at Texas Tech University was responsible for all isotopic analyses, and I owe him huge thanks for processing all samples in an extremely timely manner.

I would like to thank The School of Earth Sciences at The Ohio State University for granting me with a Graduate Teaching Associateship and the Carman Fellowship for support in the summer of 2011.

Funds from National Science Foundation Grants EAR-0517976 and EAR-

0517929 were used for laboratory materials and procedures.

Lastly, my thanks go out to all faculty and students who have assisted me in the completion of my Master’s degree. These people include (but are not limited to): Dr.

Matt Saltzman, Dr. Peter Webb, Dr. Larry Krissek, Alyssa Bancroft, Dr. Brad Cramer,

Alexa Sedlacek, Cole Edwards and, certainly not least, Dr. Bill Ausich.

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Vita

2004...... Eton College, Windsor, United Kingdom

2009...... B.A. Geology, Trinity College Dublin,

Ireland

2009 to present ...... Graduate Teaching Associate, School of

Earth Sciences, The Ohio State University

Fields of Study

Major Field: Geological Sciences

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Table of Contents

Abstract ______ii

Acknowledgments ______iv

Vita ______v

Table of Contents ______vi

List of Figures ______viii

List of Tables ______ix

Introduction ______1

Stratigraphic Summary ______4

Methods ______12

Results ______18

Western Ohio ______18

Eastern Indiana ______25

Discussion ______32

Western Ohio ______32

Eastern Indiana ______35

Conclusions ______37

References ______40

Conodont Plates ______44 vi

Appendix A: Conodont Taxonomic Discussion and Explanation of Nomenclature ____ 54

Appendix B: Conodont Processing Data ______60

Appendix C: Conodont Distribution Data ______65

Appendix D: Locality Information ______71

Appendix E: Data Tables and Cross Plots of Isotopic Analysis Data ______73

Appendix F: Details from 10MK3 Core ______85

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List of Figures

Figure 1 - A generalized conodont and δ13C stratigraphy of the study period...... 3

Figure 2 - Surface geology map of the North American Midwestern Basins and Arches region ...... 5

Figure 3 - Stratigraphic positions of Salina Group Cincinnati Arch units...... 6

Figure 4 - Silurian Stratigraphy of the Midwestern Basins and Arches Region ...... 8

Figure 5 - Stratigraphic positions of Cincinnati Arch units on the western flank ...... 9

Figure 6 - δ13C and conodont data from Con Ag Quarry...... 21

Figure 7 - δ13C and conodont data from Duff Quarry...... 24

Figure 8 - δ13C and conodont data from Anderson Falls...... 27

Figure 9 - δ13C and conodont data from the HA7 Core...... 31

Figure 10 – Biochemostratigraphy of the Salina Group of western Ohio and eastern

Indiana based on the conclusions of this report ...... 39

Figure 11 - Representative portion of 16 m – 12 m depth in the 10MK3 core...... 85

Figure 12 - Transition zone (~12m deep in 10MK3 core)...... 86

Figure 13 - 9.3m below ground surface in core...... 87

Figure 14 - 8.6m below ground surface in core...... 88

Figure 15 - 4.2 m below ground surface in core...... 89

Figure 16 - 1.3m below ground surface in core...... 90

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List of Tables

Table 1 - Conodont retrieval data from the HA7 Core ...... 60

Table 2 - Conodont retrieval data from Duff Quarry strata ...... 63

Table 3 - Conodont retrieval data from Con Ag Quarry strata ...... 64

Table 4 - Conodont distribution data from Duff Quarry...... 66

Table 5 - Conodont distribution data from Con Ag Quarry ...... 67

Table 6 - Conodont distribution data from the HA7 Core ...... 68

Table 7 : Locality information for sections featured in this report ...... 72

Table 8 - Isotopic analysis data and cross plot from 09MK1 - Con Ag Quarry ...... 73

Table 9 - Isotopic analysis data and cross plot from 10MK3 - Con Ag Quarry core ...... 74

Table 10 - Isotopic analysis data and cross plot from 10MK1/2 – Duff Quarry ...... 76

Table 11 - Isotopic analysis data and cross plot from 10MK5 - Duff Quarry ...... 78

Table 12 - Isotopic analysis data and cross plot from 08MK2 - Anderson Falls ...... 79

Table 13 - Isotopic analysis data and cross plot from HA7 Core ...... 81

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Introduction

The Silurian Period has attracted attention in recent years as a time of extreme paleoclimate cycles. Successions that were once impossible to subdivide now yield some of the most easily-recognizable stratigraphic markers in the Paleozoic. Thick successions of carbonates and shales were deposited containing abundant bio- and chemostratigraphic markers, and the resolution of Silurian divisions becomes finer as more workers worldwide apply these data to regional strata. These same marine rocks have borne viable hydrocarbons, salts, and metals and continue to be of economic interest in many parts of the world.

In recent years the integrated tools of bio- and chemostratigraphy have been increasingly used to better constrain regional units in time and space. Certain fossil groups have been determined to be facies-dependent during periods of the Silurian, and the difficulty in tracking a biozonation is made all the more taxing by the regular extinction events that punctuate the phylogenies during this part of the Paleozoic. The recognition of large δ13C excursions and their association with these extinction events has enabled Silurian workers to bridge gaps in the paleontological record, whether these gaps are facies or extinction defined.

Given the timing of extinction events, ocean chemistry changes, sea level changes and related facies changes, it is clear that these data can be tied together to produce reliable models for global change during the Silurian. These models include complex 1

positive feedback mechanisms that attempt to explain the coincidental extinction events and ocean chemistry changes and postulate changes in Earth’s atmosphere that accompanied these phenomena (e.g. Jeppsson, 1990; Munnecke et al., 2003; Saltzman,

2005; Cramer and Saltzman, 2006). An understanding of the relative timing and causation relationships is essential when addressing any Silurian stratigraphic problem, but creating and investigating hypotheses regarding the relationships of these proxies is beyond the scope of this report.

The Swedish island of Gotland has some of the thickest and most continuous exposures of Silurian outcrop on Earth, ranging from youngest Llandovery to Late

Ludlow in age. The sections on Gotland preserve δ13C excursions, graptolites and conodonts in alternating limestone-shale cycles. There do not appear to have been any significant hiatuses in deposition, and the strata are fully correlative from the type areas across the island. For this reason, the stratigraphy of Gotland, including the faunal, chemical and lithological characteristics, is becoming accepted as an excellent correlation stratotype. A good summary of the stratigraphy of Gotland and the zonations adopted there is included in Jeppsson et al. 2006. With the most recent well-developed chronology and associated biochemostratigraphy that have been developed using existing

GSSPs and the Gotland strata, high resolution correlation of regional successions is possible.

Figure 1 is a simplified interpretation of the global conodont and δ13C stratigraphy from the middle Wenlock to the lower Pridoli. Also included are the extinction events with which the excursions are associated and for which they are named.

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Figure 1 - A generalized conodont and δ13C stratigraphy of the study period. The magnitude of δ13C fluctuations can vary. After Cramer et al. (2011), Jeppsson et al. (2006) and Johnson (2006). Y axis is not to scale.

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Stratigraphic Summary

During the Wenlock through Pridoli, the North American Midwestern Basins and

Arches region was submerged as part of the Laurentian craton. The Cincinnati,

Kankakee and Findlay arches separated the three depocenters of the Illinois, Michigan and Appalachian Basins (Figure 2). In addition, the arches provided regional structural highs within a broader depositional setting, providing an area well-suited to carbonate production.

The term ‘Salina’ was originally used in central New York State by J. D. Dana

(1863). It was first applied to strata from the ‘saliferous epoch’; but after the use of these terms evolved, it was restricted to Silurian rocks of the Cayugan Series (‘Late Silurian’).

The New York succession was correlated down ramp and determined to be equivalent to thick dolomite and evaporite strata in the Michigan Basin, after which the Salina Group was adopted to describe these carbonates and their equivalents to the south along the

Findlay and Cincinnati arches (Droste and Shaver 1982). However, due to the varying thickness of Salina Group strata throughout the Great Lakes region, the sometimes- unconformable top, and the fact that major marker divisions are based on evaporites that occur only in the thickest successions, the group is very poorly understood.

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Figure 2 - Surface geology map of the North American Midwestern Basins and Arches region 5

In the Michigan Basin, the Salina Group has been divided using an A-G notation.

These divisions are identifiable in north-central Ohio (Janssens, 1977; Droste and Shaver,

1982; and others), largely thanks to the lingering presence of some evaporite deposits (A1 and A2 anhydrites). Further away from the Michigan Basin, however, these subdivisions are not recognizable. This has lead to widespread use of terms such as ‘undifferentiated’ dolomite or Salina, even in more recent work (e.g. Figure 3: Generalized Column of

Bedrock Units in Ohio (Hull 1990, rev. Slucher 2004)).

Figure 3 - Stratigraphic positions of Salina Group Cincinnati Arch units. After: Southwestern Ohio column of bedrock units (ODNR) – Hull 1990 rev. Slucher 2004 On the flanks of the Illinois, Appalachian and Michigan basins, the successions take on different characters due to lateral facies change and intermittent hiatuses of deposition across local topographic highs. For this reason, the Salina Group designation that had been applied to sequences in these marginal areas may be misleading, and strata identified as Salina Group in these areas may not be contemporaneous across the region.

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Age interpretations for Salina Group units vary due to these correlative difficulties. Swezey (2008, 2009) considered the Salina Group to range in age from late

Wenlock to Pridoli in the Illinois and Michigan Basins, except where the upper part was truncated due to erosion in the eastern Indiana section of the Illinois Basin. Rickard

(1975) and Brett et al. (1995) considered the Salina Group to range from late Ludlow to

Pridoli in age in the Appalachian Basin in New York.

The USGS interpretation of the stratigraphy in the study area has been represented most recently in published columns of the Michigan Basin and Illinois Basin (Figure 4).

The Salina Group is represented in eastern Indiana strata of the Illinois Basin and is divided into the Pleasant Mills and Wabash Formations. It is regarded as late Wenlock to late Ludlow in age and is underlain by the Salamonie Dolomite. The same succession is illustrated in northern Indiana and northwestern Ohio portions of Michigan Basin stratigraphy.

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Figure 4 - Silurian Stratigraphy of the Midwestern Basins and Arches Region, adapted from Swezey (2008, 2009)

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Stratigraphic conflicts arising from the westward extension of the New York- defined Salina Group are common. In Western Ohio the relative components and positions of the Salina Group and underlying Lockport Group are well understood.

Figure 3 is the Ohio Division of Natural Resources (ODNR) Division of Geological

Survey interpretation of the Springfield Dolomite, Cedarville Dolomite, Greenfield

Dolomite and Tymochtee Dolomite sequence.

On the western flank of the Cincinnati arch, a stratigraphy developed upon Illinois

Basin units has been applied (Figure 5).

Figure 5 - Stratigraphic positions of Cincinnati Arch units on the western flank (after Shaver et al. (1986) and Swezey (2009))

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One conflict involving the positioning of the base of the Salina Group between the study area and the type area involves the Guelph Formation, the uppermost unit within the Lockport Group in New York State.

The Salina Group’s base in Ohio has traditionally lain at the base of the

Greenfield, with the Cedarville being the uppermost unit in the Lockport Group.

Therefore, the Cedarville Dolomite and the Guelph Formation (both immediately underlying the base of the Salina Group) should be equivalent stratigraphically. The

Mulde δ13C excursion begins in rocks immediately overlying the Cedarville (normally the

Greenfield Dolomite in the study area), attributing a possible youngest age for the

Cedarville as early Homerian.

The Guelph Formation also contains the Mulde δ13C excursion (Mark Kleffner, unpublished data from Ontario, Canada), as does the Waldron Shale in Tennessee

(Cramer et al. 2006). This Waldron does not belong to the Pleasant Mills Formation, but is understood to be the same stratigraphic unit as the Waldron Member of Indiana. These isotope observations suggest that the Guelph Formation contains strata of equivalent age to the Greenfield Dolomite in Western Ohio and to the Pleasant Mills Formation

(Waldron Member) in the Illinois Basin. The Indiana Geological Survey publication

(Shaver et al. 1986) that introduces the Pleasant Mills Formation indicates that the correlative units in neighboring strata include the Greenfield and Tymochtee Dolomites in Ohio, and the Guelph in New York.

The type area evidence suggests that the equivalent of the Guelph Formation in

Indiana and Ohio should be the youngest unit in the Lockport Group. This evidence of the Mulde δ13C excursion in the Greenfield Dolomite and Waldron Member conflicts 10

with their position as Salina Group members, according to the type area for the Salina

Group.

This report investigates sections designated as Salina Group in the study area and aims to determine if good stratigraphic markers can be isolated that might further aid in a better understanding of the deposition of these units in space and time.

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Methods

Sampling

The aim of field collecting was to sample regularly and at such intervals that any change in fauna or δ13C isotope could be accurately identified and stratigraphic boundaries could be placed. Most lithologies were argillaceous dolostones, and beds were selected according to spacing and ease of sampling. Samples were collected for conodonts and isotopes from outcrop and quarry sections and cores from Salina Group strata in eastern Indiana and western Ohio at the localities shown in Figure 2 (for detailed locality information see Appendix D).

The mixing effects of bioturbation on both conodont biofacies and geochemical signals can occur over a thickness of 30-40 cm in slowly deposited sediments today (see discussion by Martin, 1999). It is unlikely that a finer-scale time resolution of events would be possible with more closely spaced samples because of the averaging effects of sediment advection. Sample intervals varied depending on locality and total meterage sampled, but typically small samples (for the purpose of δ13C and δ18O analysis) were taken every 30-40 cm. Large samples (for conodont processing) were generally collected at 1 m intervals.

Conodont sample sizes ranged between 8kg and 15kg, which was approximately the largest practical sample size possible. Jeppsson (2005) recommended sample sizes in

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the region of 50kg where possible to ensure complete recovery of conodont species at each level. It is well known that larger sample sizes allow recovery of more species, especially extremely rare taxa; but unless all levels are of equal size, comparisons among samples becomes problematic. Sampling supervised by Mark Kleffner followed a common labelling scheme of (year/collector’s initials/section number), and meterage information was recorded in field notebooks. Samples were double-bagged and double- labelled in sealable plastic bags. Bags were not reused.

Acid Digestion

Acid digestion techniques were employed to release phosphatic conodont elements from the carbonate matrix. Because the lithology was primarily argillaceous dolomite, some samples were crushed to aid digestion speeds. The method of Jeppsson and Anehus (1995) was modified to facilitate optimum conodont retrieval.

Samples were first soaked in dilute bleach solution for 24 hours and scrubbed to remove lichens or other biogenic material. All digestion equipment was cleaned prior to introduction of samples. Buckets used had a capacity of 19 liters and were filled with 14 liters water, 500g powdered CaCO3, 20g Ca3(PO4)2, and one liter industrial quality 90% strength formic acid. The product was a solution that contained ~7% acid, 33g/l CaCO3 and 1.3 g/l Ca3(PO4)2. Between 1 and 2 kg of rock were added per bucket, depending on sample size and estimated dolomite percentage in the sample lithology. Buckets were left to digest in fume hoods.

Once carbonate was dissolved samples were poured through sieves of 850μm (20 mesh) above a lower sieve of either 90μm (170 mesh) or 106μm (140 mesh) and rinsed

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thoroughly with warm water. Residues caught in the lower sieve

(90μm

Heavy Liquid Separation

Sufficiently large fine fractions were separated using tetrabromoethane (TBE), which has a density of ~2.9 g/cm3. Conodont elements have a density of between 2.90 and 3.04 g/cm3 (Jeppsson and Anehus 1999).

Fine fractions were introduced to the TBE in a 1 liter separatory funnel under a fume hood, and the mixture was stirred to release any heavy elements from potential rafting on light residue. Residues were stirred periodically over the course of 6-8 hours.

At this point heavy residue was poured through fine filter paper, and heavy liquid was allowed to run through for recycling. The light fraction was also isolated in this manner, and all residues were rinsed thoroughly with acetone and left to dry in the fume hood.

Picking and Mounting

Fine residue was spread evenly over picking dishes at a depth of no more than one grain, and a binocular reflective-light microscope was used to study the residue. A fine, wet paint brush was used to pick all conodont elements, and these were transferred to numbered cells within a micropaleontology cavity slide that had been prepared with adhesive.

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Imaging

Scanning Electron Micrograph images were taken at The Ohio State University’s

Campus Microscopy and Imaging Facility. Stubs were sputter coated in gold and imaged in a FEI Nova 400 model Nano SEM.

Light photograph images were taken using a Leica DFC290 microscope camera.

Photographic imaging is particularly useful for Silurian conodont identification as a clear view of the white matter within the denticles of some Pa elements is vital for correct species identification (e.g. Cramer et al. 2010)

Chemostratigraphic Analysis Methods

The report by Cramer et al. (2006) summarizes the evidence that micrites and fine-grained carbonates are reliable for stable isotopes stratigraphy. Samples were either carbonate mudstones or sparse skeletal wackestones bearing few skeletal grains that were avoided wherever possible. The use of dolomites in δ13C analyses studies is not uncommon, but there are additional questions that arise when analyzing data from dolomites as opposed to ‘clean’ low-Mg carbonate. The inherent processes associated with the creation of secondary dolomites do involve the exchange of ions within the rock matrix, which might result in some replacement of the carbon and oxygen within the mineral lattice. Cross plots of δ13C and δ18O are a graphical method that provides a means for determining if replacement has occurred, and are shown for all processed sections in Appendix E.

Samples for δ13C and δ18O analysis were processed by the Texas Tech University

Stable Isotope Laboratory. Isotope samples were obtained by drilling out powder from 15

sawed (non-weathered) surfaces of the carbonates. Powders were roasted for 30 min at ca. 480°C under a stream of hot, 99.99% purified helium to remove water and organic material. Samples were reacted with 100% phosphoric acid for 24 hrs in an agitated water bath maintained at 25.2°C. Evolved CO2 was extracted and purified following the method of McCrea (1950). The relative yield is the percent of measured versus theoretical yield of pure calcite (9.99μmol CO2/mg). Full yield is rarely obtained for these samples for several reasons. First, the highest measured yields from pure calcite are typically 90-95% of the theoretical value for samples reacted at 25°C. Second, acid- resistant phases such as silicates will contribute insignificant amounts of gas and lower the overall sample yield. Hence, variable yields are expected for different samples depending on the amount of non-carbonate phases. This variation in yield, however, does not imply incomplete reaction of calcite and has no effect on the isotopic values. Gas samples were analyzed on a VG SIRA-12 isotope ratio mass spectrometer equipped with a microinlet system. All values were obtained using an internal standard TTU-2 calcite, calibrated versus international standard NBS-19. All of our isotope results are reported using the conventional delta notation (Craig, 1957). Results are reported relative to V-

PDB (‰). Oxygen isotope values are adjusted using an acid-fractionation factor of

1.01025. The precision of our analysis is determined by overall method and is ± 0.1‰ and ± 0.2‰ for δ13C and δ18O, respectively. Jacobi (2004) examined the variation in isotopic values of rock powders for similar late Silurian carbonate mudstones by making replicate samples at two levels. He found that in these rocks, the four replicate values at each level differed by as much as 0.15‰ for δ13C and 0.40‰ for δ18O, a product of the

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natural heterogeneity of the rocks. Therefore, we are cautious in making interpretations for changes of less than 0.5‰ for either isotope.

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Results

Western Ohio

Con Ag Quarry, St. Mary’s, Ohio

Con Ag Quarry’s location in Auglaize County, on the eastern flank of the

Cincinnati Arch (see Figure 2; Appendix D), is advantageous due to the scarcity of outcrop in the region. The quarry penetrates the Greenfield and Cedarville Dolomites.

The quarry walls at Con Ag are mostly comprised of massive, vuggy, tan dolomite, which was not well bedded and was difficult to sample thoroughly for conodonts. These lower beds include large (4-10m across) reef-like mounds that weather into crumbly beds with wavy planes of bedding. These reef-like patches contain crinoid and sponge detrital material.

In the upper meters of the quarry, a change in lithology can be easily identified.

This is interpreted as the transition from Cedarville Dolomite to Greenfield Dolomite. At the transition from massive dolomite to argillaceous beds, there is a small package of thin

(~10cm) beds separated by discontinuity surfaces that may represent potential time gaps.

This transition zone between the Cedarville and Greenfield units was sampled at high resolution and using particularly large sample sizes.

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A core drilled by the quarry owners on property adjacent to the quarry was also sampled because it contained a greater thickness of Greenfield strata above the Cedarville transition zone. The stratigraphic column in Figure 6 features data from the core with information from the overlapping beds in the quarry superimposed. Images of the core are featured in Appendix F.

Conodont Fauna

The fauna at Con Ag Quarry is dominated by elements of the genus Panderodus.

Walliserodus, Pseudooneotodus and Ozarkodina are also represented. Yields varied from barren to 10 elements/kg.

All Ozarkodina elements are Ozarkodina excavata sspp. (Plate 4, figures 1-4).

Identification beyond species level presents challenges due to fragmentation of elements and the lack of well preserved basal cavities.

Elements of Panderodus include a possible candidate for P. greenlandensis, but the majority of the coniform elements do not display key morphologic features unique to certain Panderodus species. Similarly, identification of Walliserodus can be no more specific than genus level.

Three species of Pseudooneotodus are represented: Pseudooneotodus beckmanni

(represented by the most elements), Pseudooneotodus bicornis (Plate 4, figure 11) and

Pseudooneotodus linguicornis (Plate 4, figure 12). Calner and Jeppsson (2003) indicated that P. linguicornis was widespread and relatively common from near the base to the top of the Ozarkodina sagitta sagitta Zone, which is within the early Homerian. The same

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work indicates that P. linguicornis became extinct at Datum 1.5 of the Mulde extinction event in Gotland.

δ13Ccarb Data

The strata at Con Ag Quarry yielded what appears to be the onset of a positive

13 δ Ccarb excursion in the topmost beds of the quarry, those recognized as belonging to the

Greenfield Dolomite (Quarry data is dashed line on Figure 6). The 10MK3 core drilled on property adjacent to the Con Ag Quarry records the peak and descending limb of that

13 positive δ Ccarb excursion in Greenfield beds above those exposed at the top of the quarry itself (Figure 6; Appendix E). Reinspection of the core after the acquisition of

δ13C data indicated a close relationship between dark, muddy bands and noticeable jumps in the isotope curve, suggesting the presence and location of several hiatuses in regional

13 deposition. The fairly significant decrease in δ Ccarb values in the transition zone between the Greenfield and the Cedarville, particularly as seen in a sample from that level in the quarry (Figure 6) is suggestive of an unconformity at the level just below the onset of the excursion hosted by the Greenfield.

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Figure 6 - δ13C and conodont data from Con Ag Quarry. The quarry samples were aligned with the core data using the base of the Greenfield Dolomite. 21

Duff Quarry, Huntsville, Ohio

Duff Quarry’s location in Logan County (Figure 2; Appendix D) places it farther east or more basinward from the axis of the Cincinnati Arch, and therefore, slightly younger rocks might be expected due to the very slight basinward dip of those strata and given a lack of large-scale topographic change in the area.

The quarry walls are almost entirely comprised of massive, tan, silty dolomite with abundant stromatolites and mudcracks but contain few features that could be used in regional stratigraphic correlation. This gives way in the upper few meters to siltier dolomite with more evident bedding. The strata are an example of what is referred to as

‘undifferentiated Salina Group’ and were identified as such by Carlson (1991). These are the same as the ‘undifferentiated dolomite’ shown in Figures 3 and 5 or simply

‘dolomite’ in regional stratigraphic charts (e.g. Hull 1990 rev. Slucher 2004).

Conodont Fauna

The strata at Duff Quarry returned variable yields. Some strata were barren even though as much as 10kg of rock was digested; but toward the top of the quarry some of the more argillaceous beds produced yields of up to 30 elements/kg (Appendix B)

The fauna in Duff Quarry appears to be of low taxonomic diversity. Two genera are represented, Oulodus and Ozarkodina (Figure 7; Appendix C). Specimens of the genus Oulodus show similarities to Oulodus elegans and Oulodus siluricus, but do not match either species well enough to be assigned confidently. The indicative Pa and Pb elements were absent.

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There was a large amount of variation in the Ozarkodina fauna, making it difficult to definitively recognize species. Appendix A includes a taxonomic discussion of the elements representing Ozarkodina and Oulodus from Duff Quarry, which includes a description of the important characters of the elements as well as possible species and/or stratigraphic level associated with elements possessing those characters.

δ13Ccarb Data

13 The strata at Duff Quarry did not yield any significant positive fluctuations in δ Ccarb

13 values (Fig 7, Appendix E). δ Ccarb values from samples collected from the upper part of the quarry (dashed line on Figure 7) record a decrease of almost 2 ‰ over a 4.6 m interval.

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Figure 7 - δ13C and conodont data from Duff Quarry. 0m datum is 0m in 10MK5, equivalent to 8.30 m in 10MK1/2 24

Eastern Indiana

Anderson Falls

The Waldron Member of the Pleasant Mills Formation is well known in the

Illinois Basin, especially in Indiana. It can be traced southward into Tennessee and is famous for its echinoderm fauna. The Anderson Falls locality (Figure 2; Appendix D) includes an exposure of the Waldron Member that is more calcareous than most Waldron in Indiana and elsewhere. The reason for this might be that a topographic high seems to have existed in the area of southeastern Indiana during the time of deposition, which could have resulted in a shallower depositional environment more conducive to carbonate production. The sampled exposure is located closer to the axis of the Cincinnati Arch than the more clastic outcrops farther west, and thus the outcrop sampled might have been more liable to have undergone periods of exposure and erosion during deposition.

2.5 m of Waldron Shale along the Falls Fork of Clifty Creek (Figure 8) was sampled, north of the intersection of East County Road 200 N and North 1140 County

Road E, Bartholomew County. No conodonts were found after processing of samples from this locality, despite the promising facies

δ13Ccarb Data

13 δ Ccarb values from Anderson Falls clearly record a positive excursion (Figure 8;

13 Appendix E). δ Ccarb values increase from a low of +1.78 ‰ just above the base of the

13 Waldron to a peak value of + 4.76 ‰ at 1.8 m above the base. δ Ccarb values then decrease rather abruptly just above the peak value to +3.38 ‰, and remain constant until

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a sample from just below the top of the Waldron Member where the value again increases to +3.76 ‰. Due to the unconformable top to the Waldron Member at this locality it is

13 unclear whether the δ Ccarb values could be expected to fall or rise farther above this point.

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Figure 8 - δ13C and conodont data from Anderson Falls. 0m datum at base of Waldron Member. 27

HA7 Core

The Indiana Geological Survey HA7 Core was originally drilled by the Northern

Indiana Public Service Company in Steuben County, northeastern Indiana (Figure 2;

Appendix D). Initial observations on the core were made by Robert Shaver of the

Indiana Geological Survey in 1966. Carl Rexroad divided the core into 4 ft sections and then crushed and bagged each section in preparation for processing for the purposes of biostratigraphy in Rexroad (1980). Thus, the highest resolution with which we can plot carbon data is within a 4 ft window. The only lithologic observations are from Shaver’s original notes, and it is these that were used to reconstruct the lithologic column alongside the δ13C data (Figure 9). Shaver also updated his notes with Michigan Basin correlation suggestions in 1984, and these are also tentatively included.

A section of the core (1062 ft to 1081 ft below land surface) was not available for processing, having been retained by the Northern Indiana Public Services Company. Carl

Rexroad processed 1kg of most samples through the studied interval and the conodonts he recovered were available for this report, along with samples processed specifically for this report. The HA7 samples that were processed for δ13C were from the depths between

844.2 ft and 1328 ft below land surface according to the original core measurements.

These depths correspond to crushed intervals HA7-93 to HA7-221, and these are the sample numbers utilized. Depths were converted to m below HA7-93 for the purposes of data presentation (Figure 9).

28

Conodont Fauna

Many of the samples processed yielded few or no conodonts (Appendix B). Of the well-preserved elements in residues from this core, the majority are Ozarkodina confluens. Additional elements represented include Ozarkodina bohemica longa, O. snajdri, and Oulodus sp. (Figure 9; Appendix C).

Ozarkodina bohemica longa is the index for the Homerian conodont zone of that name, and its range is from the base of Subzone 1 of the O. bohemica longa Zone through the Ctenognathodus murchisoni Zone and possibly above that zone as well

(Calner and Jeppsson, 2003). A single Pa element of this subspecies (Plate 4, figure 9) was recovered from a level (~97 m below the top of processed core - sample number

13 HA7 179) within the lower part of the large positive δ Ccarb excursion recognized near the middle of the sampled core (Figure 9).

In some of the youngest rocks studied (0.9 m below top of studied section, 848 ft below ground surface in core – HA7 95) two small (juvenile?) elements of Ozarkodina snajdri were recovered (Plate 4, figures 7 & 8). Oz. snajdri is the nominative species of a middle Ludlow conodont interval zone (stage slice Lu2 of Cramer et al., 2011), but ranges from at least the earlier Ludlow Polygnathoides siluricus Zone to at least the early

Pridoli (Corradini and Serpagli, 1999)

A juvenile Pa element possibly representing Kockelella stauros was also recovered from strata 1156 ft below the top of core, or 95 m deep into our sampling (HA7

177). This level is above the recovered Pa element of Oz. bohemica longa. Jeppsson

(1998; Figure 5), indicates that the first occurrence of that species is in strata Calner and

Jeppsson (2003) assign to the K. ortus absidata Zone. 29

δ13Ccarb Data

13 The depth of the HA7 core makes it an excellent candidate for δ Ccarb analysis, at the expense of outcrop-level lithological observation. The core (Figure 9; Appendix E)

13 records a positive δ Ccarb excursion through a considerable thickness (65m to108m

13 below the top of processed core). A single δ Ccarb value at 32.6 m below the top of the processed core (+2.63 ‰) is more than 2 ‰ higher than both the subjacent (0.32 ‰) and suprajacent (0.36 ‰) values (Figure 9; Appendix E).

30

Figure 9 - δ13C and conodont data from the HA7 Core. Lithology designations and unit correlations are courtesy of Robert Shaver's observations before the core was crushed, and are speculative. Letter designations refer to Michigan Basin Salina Group divisions. 0m datum is at the youngest sample processed, equivalent to 845 ft depth in original core. 31

Discussion

Western Ohio

Con Ag Quarry

While the panderodids from Con Ag Quarry dominated the fauna and are rarely useful for biostratigraphy, elements of another coniform species within this fauna,

Pseudooneotodus, do prove useful. Pseudooneotodus linguicornis, represented in two samples from the quarry, has been shown to become extinct at Datum 1.5 of the Mulde

Event in Gotland (Calner and Jeppsson 2003). The highest occurrence of P. linguicornis in the quarry is at the transition zone between the Cedarville Dolomite and Greenfield

13 Dolomite, which is nearly coincident with the onset of the δ Ccarb excursion in the basal

Greenfield Dolomite.

Datum 1.5 of the Mulde Event is at the base of subzone 1 of the Ozarkodina bohemica longa Zone, and the top of that subzone represents the onset of the late

13 Wenlock Mulde positive δ Ccarb excursion (Cramer et al., 2006, Fig. 5). That relationship is the exact sequence in the transition zone strata in the Con Ag Quarry, followed by a

13 peak or peaks of the positive δ Ccarb excursion between 2.0 and 4.0 m above in the lower part of the Greenfield. This indicates that the upper part of the Cedarville Dolomite and all of the overlying Greenfield Dolomite in the quarry and core from the adjacent property are Homerian in age and record both the Mulde Event (at level of the highest 32

occurrence of P. linguicornis) and Mulde Excursion (in the 12 m of Greenfield Dolomite present in the core, the lowermost 2.0 m of which are also exposed at the top of the

13 quarry). There is an abrupt increase in δ Ccarb values from samples in the transition zone between Cedarville and Greenfield, particularly in samples from that interval in the quarry, and there is evidence for discontinuity surfaces that could represent missing time

(Appendix F, Figure 12: middle column of core). Additionally there are not two obvious

13 peaks to the δ Ccarb isotope curve on Figure 6, yet the Mulde Excursion is a two-peaked excursion with the first peak within the Ozarkodina bohemica longa Zone and the second peak in the Kockelella ortus absidata Zone (Cramer et al., 2011). Thereby, it is also possible that the Mulde Excursion is not recorded in its entirety in the quarry and core, or that it is only the second peak of the excursion represented in the Greenfield Dolomite at the quarry. If the peak recorded in the Greenfield is the second peak, then the missing time represented by the discontinuity surfaces could be part or all of the early Homerian through middle Homerian (part of Ozarkodina sagitta sagitta, all of O. bohemica longa, and part of Kockelella ortus absidata Zones).

Duff Quarry

The conodont fauna from Duff Quarry strata may not be composed of species that are readily assignable to previously recognized zones, but even if all of the species represented are endemic, they do provide some evidence for the age of those strata, and need not necessarily be useless in future. As is discussed in Appendix A: Conodont

Taxonomy, many of the elements recovered are definitely of Ozarkodina confluens

33

affinity. Several previous studies have recognized different morphotypes of Ozarkodina confluens or different species definitely related to that species (Klapper and Murphy,

1975; Helfrich, 1975; Viira, 1983, 2000) that have proven to be useful in biostratigraphy.

Ozarkodina sp. A (Plates 1, 2, and 3) and Ozarkodina sp. B (Plate 1, figure 1) of this report are composed of Pa elements that are comparable to Pa elements of species recognized by Helfrich (1975) and Viira (2000) to have ranges restricted to the Late

Silurian, either the Ludlow or Pridoli. Pa elements closely resembling Spathognathodus primus multidentatus, which Helfrich (1975) isolated from the Wills Creek Formation of

Ludlow age in the Appalachian Basin, occur in a sample 5.0-m above the base of the

Duff Quarry section.

The presence of Oulodus elements in the upper part of the quarry (Plate 3, figures

5-10), which have clear indications of belonging to species no older than latest

Ludfordian, and more likely Pridoli (Appendix A), provides additional evidence that the dolomites at Duff Quarry are Ludlow or Pridoli in age.

13 There is no record of a positive δ Ccarb excursion in Duff Quarry strata (Figure

13 7). Conodont biostratigraphy suggests that the only δ Ccarb excursion that could be recorded would be the Ludlow Lau Excursion, as there are no other obvious positive excursions recorded in Ludlow or Pridoli strata (Fig. 3 in Cramer et al., 2011).

34

Eastern Indiana

Anderson Falls

13 Cramer et al. (2006) recognized the Homerian Mulde δ Ccarb excursion in the

Waldron of Tennessee. The lack of any conodonts prevents recognition of the level of the Mulde Event in either the Waldron or underlying Laurel Member of the Salamonie

Formation. However, previous conodont biostratigraphies developed for the Salamonie

(Rexroad, 1980) and Louisville Limestone and Wabash Formation (Rexroad et al., 1978) indicate that the Sheinwoodian Ireviken excursion must be well below the Waldron, and the Ludfordian Lau excursion must be well above the Waldron. Thus, the only positive

13 δ Ccarb excursion that could be recorded in the Waldron at Anderson Falls (Figure 8) is the Mulde Excursion (Cramer et al., 2011; Fig. 3). The unconformity at the top of the

Waldron at Anderson Falls may cut out at least a portion of the Mulde Excursion, as the

13 δ Ccarb values are increasing, rather than decreasing in the uppermost Waldron. It is possible that the two peaks in the excursion at Anderson Falls are the two peaks of the

13 Mulde Excursion, but it is also possible that increasing δ Ccarb values in the uppermost

Waldron would have continued to another, second, peak that was cut out due to the unconformity.

HA7 Core

13 The δ Ccarb excursion recorded in more than 40 ft of strata in the HA7 core is

13 identified as the Mulde δ Ccarb excursion, and this is supported by the presence of

Ozarkodina bohemica longa in sample HA7-179, which lies 10 m above the beginning of

35

the excursion. A broken juvenile element (Plate 4, figure 10) recovered from 12 m above the beginning of the excursion is probably the Pa element of Kockelella stauros, which

Calner and Jeppsson (2003) indicated was partly coeval with K. ortus absidata, the index of the conodont zone following the O. bohemica longa Zone.

Two specimens representing Ozarkodina snajdri in some of the youngest beds in

13 the core do not contribute much to a level at which to identify the Lau δ Ccarb excursion in this core, as O. snajdri has a relatively long range. However, in North America, O. snajdri appeared just above the mid-Ludlow conodont extinction level (Barrick et al.

(2010), known as the Lau Event, and according to Corradini and Serpagli (1999) ranges

13 into the Pridoli in some locations. The one seemingly anomalous δ Ccarb value of + 2.63 from a sample 32.6 m below the top of the processed core cannot be definitively ruled out as a greatly truncated record of the middle to late Ludfordian Lau Excursion. That sample is located well above the Homerian Mulde Excursion and below the two specimens representing O. snajdri in the core that could represent O. snajdri of the O. crispa Zone or early Pridoli.

36

Conclusions

13 Duff Quarry contains no significant positive δ Ccarb fluctuations, and thus a true integrated biochemostratigraphy is not possible. The conodont fauna from Duff Quarry is varied and the majority of the normally-diagnostic Pa elements belong to species that may be endemic and not previously documented in any studies. The most comparable fauna is one described by Helfrich (1975) from the Wills Creek Formation in the

Appalachian Basin that he determined to be Ludlow in age. Elements of Oulodus from the upper part of the quarry seem to indicate a late Ludlow to Pridoli age for strata in that

13 portion of the quarry. The lack of a positive δ Ccarb excursion and absence of truly diagnostic conodont species prevent a definitive correlation or age determination for the

Salina strata in the Duff Quarry (Figure 10).

Con Ag Quarry, which lies closer to the exposed Ordovician center of the arch, does not contain any diagnostic Pa elements of Ozarkodina or Kockelella. However, the recovery of Pseudooneotodus linguicornis in the transition between the Cedarville

Dolomite and the Greenfield Dolomite, when partnered with recognition of the Mulde excursion in the immediately overlying rocks, constrains at least part of the Mulde excursion to the Greenfield; and thus, the age of the Greenfield is middle to late

Homerian (Figure 10).

37

13 The recognition of the Mulde δ Ccarb excursion in strata assigned to the lower part of the Salina Group, Waldron Member of the Pleasant Mills Formation, on the

Indiana flank of the Cincinnati Arch further supports recent work identifying the excursion in the Waldron elsewhere. Additionally this provides correlation with the basal unit of the Salina Group, the Greenfield Dolomite, in western Ohio; with strata tentatively recognized as the basal unit of the Salina Group, A unit, in the Michigan

Basin; and at least in part with the uppermost unit of the Lockport Group, Guelph

Formation, in Ontario, Canada. The last correlation provides evidence that the uppermost part of the Lockport Group, at least in some areas, was likely in a facies relationship with the lowermost part of the Salina Group.

The probable unconformity within the transitional beds between the Cedarville and Greenfield in the Con Ag Quarry in western Ohio is at the top of the Ozarkodina sagitta sagitta Zone, exactly the same level at which Johnson (2006) recognized eaustatic

13 sea-level drop in the early Homerian. The incomplete record of the Mulde δ Ccarb excursion in the Greenfield Dolomite in the Con Ag Quarry and core is similar to the incomplete records of that excursion recognized in strata in Texas and Oklahoma by

Barrick et al. (2009), and could be a result of that early Homerian sea-level drop.

The Ludfordian Lau Excursion was not possible to recognize definitively in any

13 of the sections studied. The level of the single δ Ccarb value in the upper part of the HA7

13 core from northeastern Indiana that was more than + 2.0 greater than δ Ccarb values from underlying and overlying samples and deserves further investigation as a possible level for the Lau Excursion. Similar cores through Michigan Basin strata could be excellent material for future study. 38

Figure 10 – Biochemostratigraphy of the Salina Group of western Ohio and eastern Indiana based on the conclusions of this report 39

References

Brett, C. E., Tepper, D. H., Goodman, W. M., Loduca, S. T. And Eckert, B. 1995. Revised stratigraphy and correlations of the Niagaran Provincial Series (Medina, Clinton, and Lockport Groups) in the type area of western New York: U.S. Geological Survey Bulletin, #2086, 66 p. Barrick, J. E., 1983. Wenlockian (Silurian) Conodont Biostratigraphy, Biofacies, and Carbonate Lithofacies, Wayne Formation, Central Tennessee. Journal of Paleontology, 57: 2 p. 208-239 Barrick, J. E. and G. Klapper, 1976. Multielement Silurian (late Ladoverian- Wenlockian) conodonts of the Clarita Formation, Arbuckle Mountains, Oklahoma, and the phylogeny of Kockelella. Geologica et Paleontologica 10, 59-100. Barrick, J. E., M. A. Kleffner, M. A. Gibson, F. N. Peavy and H. R. Karlsson, 2010. The mid-Ludfordian Lau event and carbon isotope excursion (Ludlow, Silurian) in southern Laurentia; preliminary results. In: Time and life in the Silurian; a multidisciplinary approach; Subcommission on Silurian Stratigraphy field meeting 2009; proceedings. Bollettino della Societa Paleontologica Italiana 49:1, 13-33. Barrick, J. E., M. A. Kleffner and H. R. Karlsson, 2009. Conodont faunas and stable isotopes across the Mulde event (late Wenlock; Silurian) in southwestern Laurentia (south-central Oklahoma and subsurface west Texas). In: Conodont Studies Commemorating the 150'h Anniversary ofthe First Conodont Paper (Pander, 1856) and the 40'h Anniversary of the Pander Society, D. J. Over, Editor. Palaeontographica Americana 62, p. 41-56. Calner, M. and L. Jeppsson, 2003. Carbonate platform evolution and conodont stratigraphy during the middle Silurian Mulde Event, Gotland, Sweden. Geological magazine, 140, p. 173 – 203. Carlson, E. H. 1991. Minerals of Ohio. Ohio Division of Natural Resources - Geological Survey Bulletin 69, 155 p. Corradini, C. and E. Serpagli, 1998. Taxonomy and Evolution of Kockelella (Conodonta) from the Silurian of Sardinia (Italy). In: Studies on conodonts; proceeding of the Seventh European conodont symposium. Bolletina della Societa Paleontologica Italiana, 37:2-3, p 255-273. Craig, H., 1957. Isotopic standards for carbon and oxygen and correction factors for mass spectrometric analysis of carbon dioxide. Geochimica et Cosmochimica Acta 12, 133-149

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Cramer, B.D., 2010. Paleobiogeography, high-resolution stratigraphy, and the future of Paleozoic biostratigraphy: Fine-scale diachroneity of the Wenlock (Silurian) conodont Kockellela walliseri: Palaeogeography, Palaeoclimatology, Palaeoecology 294, 232-24 Cramer, B. D., C. E. Brett, M. J. Melchin, P. Männik, M. A. Kleffner, P. I. McLaughlin, D. K. Loydell, A. Munnecke, L. Jeppsson, C. Corradini, F. R. Brunton and M. R. Saltzman, 2011. Revised correlation of Silurian Provincial Series of North America with global and regional chronostratigraphic units and δ13Ccarb chemostratigraphy. Lethaia, 44:185-202. Cramer, B. D., M. A. Kleffner and M. R. Saltzman, 2006. The Late Wenlock Mulde positive carbon isotope (δ13Ccarb) excursion in North America. GFF, 128: 2, 85 – 90. Cramer, B.D. and M. R. Saltzman, 2006. Fluctuations in epeiric sea carbonate production during Silurian positive carbon isotope excursions: A review of proposed paleoceanographic models. Palaeogeography. Palaeoclimatology. Palaeoecology. 245, p. 37-45 Cramer, B.D., Saltzman, M.R. & Kleffner, M.A., 2006. Spatial and temporal variability in organic carbon burial during global positive carbon isotope δ13Ccarb excursions: new insight from high-resolution δ13Ccarb stratigraphy from the type area of the Niagaran (Silurian) Provincial Series: Stratigraphy 2, 327-340. Cramer , B. D., Kleffner, M. A., Brett, C. E., Mclaughlin, P. I., Jeppsson, L., Munnecke, A., Samtleben, C. 2010. Paleobiogeography, high-resolution stratigraphy, and the future of Paleozoic biostratigraphy: Fine-scale diachroneity of the Wenlock (Silurian) conodont Kockelella walliseri. Palaeogeography Palaeoclimatology Palaeoecology 294(3-4):232-241. Dana, J. D. 1863. Manual of geology: Treating of the principles of the science with special reference to American geological history. Ivison, Blakeman, Taylor and Co., New York, 924p. Droste, J. B., & Shaver, R. H. 1982. The Salina Group (Middle and Upper Silurian) of Indiana. Indiana Geological Survey Special Report 24, 41p. Helfrich, C. T., 1975. Silurian Conodonts from Wills Mountain Anticline, Virginia, West Virginia, and Maryland. The Geological Society of America Special Paper 161. 82 pp. Hull D. N. 1990 Rev. Slucher E. R. 2004. Generalized Column of Bedrock Units in Ohio. Ohio Department of Natural Resources, Division of Geological Survey, 1p. Jacobi, D. J., 2004. Stable Isotope Chemostratigraphy Across the Silurian-Devonian Boundary in Oklahoma and West Texas. Unpublished Master’s thesis, Texas Tech University, Lubbock, TX, 97pp.

41

Janssens, A. 1977. Silurian rocks in the subsurface of northwestern Ohio. Ohio Department of Natural Resources Division of Geological Survey, Report of Investigations No. 100, 96 p. Jeppsson, L., 1990. An oceanic model for lithological and faunal changes tested on the Silurian record. Journal of the Geological Society, London, 147 p. 663-674 Jeppsson L., 1998. Silurian oceanic events; summary of general characteristics. In: Silurian cycles; linkages of dynamic stratigraphy with atmospheric, oceanic and tectonic changes. New York State Museum Bulletin 491, p. 239-257. Jeppsson, L., 2005. Bias in the recovery and interpretation of micropalaeontological data. In Purnell, M. A. and Donoghue, P. C. J. (eds.) Conodont biology and phylogeny: Interpreting the fossil record. The Palaeontological Association Special Papers in Palaeontology 73, 57-71. Jeppsson, L. and Anehus, R., 1995. A Buffered Formic Acid Technique for Conodont Extraction: Journal of Paleontology 69, 790-794 Jeppsson, L. and Anehus, R., 1999. A new technique to separate conodont elements from heavier minerals: Alcheringa: An Australasian Journal of Palaeontology 23, 57-62.\ Jeppsson, L., M.E. Eriksson and M. Calner. 2006. A latest Llandovery to latest Ludlow high-resolution biostratigraphy based on the Silurian of Gotland – a summary. GFF, 128:109–114. Jeppsson, L., V. Viira and P. Mannik, (1994). Silurian conodont-based correlations between Gotland (Sweden) and Saaremaa (Estonia). Geological Magazine. 131:2, p. 201-218. Johnson, M. E. 2006. Relationship of Silurian sea-level fluctuations to oceanic episodes and events. GFF, 128:115-121 Klapper, G. and M. A. Murphy, 1974. Silurian-lower Devonian conodont sequence in the Roberts Mountains Formation of central Nevada. University of California Publication in Geological Sciences 111, 68pp. McCrea, J., 1950. The isotope chemistry of carbonates and a paleotemperature time scale: Journal of Chemical Physics 18, 849-857. Martin, R. E., 1999. Taphonomy: A process approach. Cambridge University Press, Cambridge, U.K., 508 pp. Munnecke, A., C.Samtleben and T. Bickert, 2003. The Ireviken Event in the lower Silurian of Gotland, Sweden – relation to similar Palaeozoic and Proterozoic events. Palaeogeography, Palaeoclimatology, Palaeoecology 195, p. 99-124. Munnecke, A., Westphal, H., Reijmer, J.J.G. & Samtleben, C. 1997. Microspar development during early marine burial diagenesis: a comparison of Pliocene carbonates from the Bahamas with Silurian limestones from Gotland (Sweden). Sedimentology, 44:977–990.

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Orton, E., 1871. The geology of Highland County. Ohio Geological Survey, Report of Progress for 1870, p. 253-310. Rexroad, C. B., 1980. Stratigraphy and conodont paleontology of the Cataract Formation and the Salamonie Dolomite (Silurian) in northeastern Indiana. Indiana Geological Survey Bulletin 58. Rexroad, C. B., A. V. Noland and C. A. Pollock, 1978. Conodonts from the Louisville Limestone and the Wabash Formation (Silurian) in Clark County, Indiana and Jefferson County, Kentucky. Indiana Geological Survey Special Report 16, 19pp. Rickard, L.V. 1975. Correlation of the Silurian and Devonian Rocks in New York State. New York State Museum and Science Service: Map and Chart Series No. 24. 16 p., 4 plates. Saltzman, M.R. 2005. Phosphorus, nitrogen, and the redox evolution of the Paleozoic oceans. Geology, 33:573–576. Shaver, R. H., C. H. Ault, A. M. Burger, D. D. Carr, J. B. Droste, D. L. Eggert, H. H. Gray, D. Harper, N R Hasenmueller, W. A. Hasenmueller, A. S. Horowitz, H C Hutchinson, B. D Keith, S. J. Keller, J. B. Patton, C. B. Rexroad, C. D. Weir, 1986. Compendium of Paleozoic Rock-Unit Stratigraphy in Indiana – A Revision. Indiana Geological Survey Bulletin 59. 203 pp. Sweet, W. C. and H. P. Schönlaub, 1975. Conodonts of the Genus Oulodus Branson and Mehl, 1933. Geologica et Palaeontologica. 9, 41-59. Swezey, C. S. 2002. Regional stratigraphy and petroleum systems of the Appalachian basin, North America. US Geological Survey Geologic Investigations Series Map 2768. 1p. Swezey, C. S. 2008. Regional stratigraphy and petroleum systems of the Michigan basin, North America. US Geological Survey Geologic Investigations Series Map 2978. 1p. Swezey, C. S. 2009. Regional stratigraphy and petroleum systems of the Illinois basin, North America. US Geological Survey Geologic Investigations Series Map 3068. 1p. Viira, V., 1983. Upper Silurian Spathognathodus (Conodonts) from Estonia. In Palaeontology of early Paleozoic of the East Baltic and Podolia (ed. E. Klaamann), p. 41-71. Academy of Sciences of the Estonian SSR, Institute of Geology (in Russian). Viira, V., 2000. Latest Silurian (Ohesaare Stage) Conodonts and the Detorta Zone in the Northern East Baltic. Proceedings of the Estonian Academy of Sciences – Geology. 49:1 – p. 44-62. Walliser, O. H., 1964. Conodonten de Silurs. Abh. Hess. L.-Amt forsch. 41, p 1-106.

43

Conodont Plates

All Pa elements are imaged with the posterior to the left with the exception of Plate 2 figure 4 and Plate 4 figure 9b. All scale bars are 500μm

Plate 1 1- Pa Ozarkodina sp. B – 04MK2-4, 1.35 m below top of quarry

2- Pa Ozarkodina sp. A – 04MK2-4, 1.35 m below top of quarry

3- Pa Ozarkodina sp. A? – 04MK2-4, 1.35 m below top of quarry

4- Pa Ozarkodina sp. B? – 04MK2-0, 4.85 m below top of quarry

5- Pa Ozarkodina sp. A? – 04MK2-0, 4 85 m below top of quarry

6- Pb Ozarkodina sp. A? – 04MK2-0, 4 85 m below top of quarry

44

45

Plate 2

1- Pa Ozarkodina sp. A – 10MK5-11, 3.3 m above base of log

2- Pa Ozarkodina sp. A – 10MK5-11, 3.3 m above base of log

3- Pa Ozarkodina sp. A – 10MK5-11, 3.3 m above base of log

4- Pa Ozarkodina sp. A – 10MK5-11, 3.3 m above base of log

5- Pb Ozarkodina sp. A – 10MK5-15, 4.6 m above base of log

6- Pa Ozarkodina sp. A – 10MK5-15, 4.6 m above base of log

7- Pa Ozarkodina sp. A – 10MK5-15, 4.6 m above base of log

8- Pa Ozarkodina sp. A – 10MK5-15, 4.6 m above base of log

46

47

Plate 3

1- Pb Ozarkodina sp. A – 10MK5-21 – 6.7 m above base of log

2- Pa Ozarkodina sp. A – 10MK5-21 – 6.7 m above base of log

3- Pa Ozarkodina sp. A – 10MK5-21 – 6.7 m above base of log

4- Pa Ozarkodina sp. A – 10MK5-21 – 6.7 m above base of log

5- Sa Oulodus sp. – 10MK5-21 – 6.7 m above base of log

6- Sc Oulodus sp. – 10MK5-21 – 6.7 m above base of log

7- Sb Oulodus sp. – 10MK5-21 – 6.7 m above base of log

8- Sa Oulodus sp. – 10MK5-21 – 6.7 m above base of log

9- M Oulodus sp. – 10MK5-21 – 6.7 m above base of log

10- Sb Oulodus sp. – 10MK5-21 – 6.7 m above base of log

48

49

Plate 4

1- Pa O. excavata ssp. – 09MK1-4, 1.5 m above base

2- Pa O. excavata ssp. – 09MK1-4, 1.5 m above base

3- Pa O. excavata ssp. – 09MK1-4, 1.5 m above base

4- Sc O. excavata ssp. – 09MK1-4, 1.5 m above base

5- Pa O. confluens densidentata? – 10MK2-33, 3.3 m below 0m datum

6- Pa Ozarkodina sp. – 10MK2-33, 3.3 m below 0m datum

7- Pa O. snajdri – HA7-95, 0.9 m below 0 m datum

8- Pa O. snajdri – HA7-95, 0.9 m below 0m datum

9- Pa O. bohemica longa – HA7-179, 97m below 0m datum

10- Pa Kockelella stauros? – HA7-177, 95 m below shallowest 0m datum

11- Pseudooneotodus bicornis – 10MK4-4, 4.4 m above base of 09MK1

12- Pseudooneotodus linguicornis – 10MK4-4, 4.4 m above base of 09MK1

50

51

Plate 5 HA7

1- Pa O. confluens – HA7-142, 48.5 m below 0m datum

2- Pa O. confluens – HA7-143, 49.7 m below 0m datum

3- Pa O. confluens- HA7-143, 49.7 m below 0m datum

4- Pa O. confluens - HA7-143, 49.7 m below 0m datum

5- Pa O. confluens - HA7-143, 49.7 m below 0m datum

6- Pa O. confluens - HA7-143, 49.7 m below 0m datum

7- Pa O. confluens – HA7-145, 52.2m below 0m datum

8- Sa O. confluens – HA7-149, 56.0m below 0m datum

9- Pa O. confluens – HA7-149, 56.0m below 0m datum

52

53

Appendix A: Conodont Taxonomic Discussion and Explanation of

Nomenclature

Duff Quarry

The Ozarkodina specimens included abundant Pa elements and entire apparatuses could be assembled from elements in some samples. The Pa elements are of O. confluens affinity, but although some do resemble Pa elements of previously described Ozarkodina confluens subspecies or O. confluens- related species that have proven useful for zonations, it is most likely that the Pa elements herein are of endemic species. There are probably no more than three species or subspecies represented, and the natural variation within the fauna is great enough that similarities to previously described forms in the literature have been helpful, yet ultimately inconclusive.

The best likeness of the majority of the Ozarkodina Pa elements in the strata at

Duff seems to be a new subspecies described by Helfrich (1975), Spathognathodus primus highlandensis. In this report the Pa elements on Plate 1, figure 2 and Plate 2, figure 1 resemble most closely the holotype imaged in Helfrich (1975, Plate 14, figure

23), but the variability in his diagnosis of that subspecies is so great that distribution of those forms in his study isn’t possible without studying his actual collections. Specific characters that many of the Ozarkodina Pa elements share in common with Helfrich’s holotype include: prominent cusp that is steeply (~15-20º) inclined posteriorly; anterior 54

denticles inclined toward the anterior; and a lack of prominent anterior cockscomb – a feature of most Pa elements of O. confluens affinity. Pa elements in Duff Quarry samples that have similar morphology to this subspecies are referred to herein as Ozarkodina sp.

A.

Common morphologic variations among the Pa elements of Ozarkodina sp A from Duff Quarry compared to the holotype of Spathognathodus primus highlandensis include the angle of the anterior denticles and the shape of the aboral margin.

Viira (2000) described another Ozarkodina species with similar denticulation:

Ozarkodina denticulata. The systematic paleontology described a small basal cavity, and a slight ascent of the aboral margin in both directions and stipulated that the anterior part of the blade may be slightly higher than the posterior. Fine striations described as characteristic of O. denticulata are absent for the most part in elements from Duff

Quarry, except for the two imaged specimens from 10MK2-33: Plate 4 figures 5 and 6.

However, these two Pa elements have several other characteristics that are more comparable with other previously defined conodonts. Pa elements from Duff that have similar morphology to O. denticulata are referred to herein as Ozarkodina sp. B.

The Oulodus fauna in the strata at Duff appears more diverse, but even the most complete elements and apparatuses are challenging to identify with confidence. Many of the elements are fragments but are identifiable as Oulodus sp. by the robustness of the body of the elements and the round cross section of the denticles. Some of the most complete elements are also the smallest, but there were no complete specimens of Pa or

Pb elements that might have aided in identification.

55

The most complete representatives are imaged in Plate 3 (figures 5-10). These elements are smaller than many of the broken Sa, Sb, Sc, and M elements from Duff

Quarry strata. Of the imaged elements on Plate 3, figures 5, 6, 7, and 8 have small denticles between the cusp and adjacent larger denticles on one or both sides of the cusp.

This is a characteristic of certain elements of the apparatus of Oulodus elegans (Walliser

1964), the multielement taxonomy of which is discussed and illustrated in Sweet and

Schönlaub (1975).

Despite the diagnostic small denticles on either side of the cusp, there are several morphological characters on those Oulodus elements from the Duff Quarry that do not match characters of Oulodus elegans as diagnosed in Sweet and Schönlaub (1975). Plate

3, figures 5 and 8 are both Sa elements with small denticles flanking the cusp. But these do not match the illustrated Sa element of Sweet and Schönlaub in that the basal cavity is turned up posteriorly only approximately one third of the way to the base of the cusp. In comparison, Sweet and Schönlaub’s Sa element’s basal cavity is turned up posteriorly to a height equivalent to approximately one third of the distance to the tip of the central cusp. Figure 6 on Plate 2 (Sc element) does not have the same posterior angle on the anterolateral process as the Sc element of O. elegans in Sweet and Schönlaub (1975).

No oulodids with small denticles flanking the main cusp have been reported from strata older than the Pridoli, and Sweet and Schönlaub (1975) were quite confident that

Oulodus elegans does not extend into older strata. Therefore, although the elements from

Duff Quarry are not necessarily Oulodus elegans, it is unlikely that they could be older than latest Ludfordian.

56

A single element from Duff Quarry raised further questions regarding the age of the strata. Plate 4 figure 5 is a Pa element of O. confluens affinity, but the anterior portion of the blade has been broken away. On the portion of the blade that is preserved, at least 20 denticles can be counted, 14 of which are located posterior to the cusp. The total number of denticles and the number located posterior to the cusp are both more than most O. confluens affinity Pa elements would have. Pa elements with this high number of denticles have been recognized previously as Spathognathodus primus multidentatus by Helfrich (1975) and Spathognathodus primus densidentatus by Viira (1983).

Helfrich’s holotype for Spathognathodus primus multidentatus has 24 total denticles of similar relative length and breadth as the specimen in Plate 4 herein. The distinctive aboral margin shape of the Duff Quarry element is not comparable due to the fact that

Helfrich’s specimens still have their basal filling intact. A comparable Pa element

Helfrich (1975) considered synonymous with his subspecies is illustrated in Walliser

(1964; Pl. 22, fig. 14). The subspecies described in Viira (1983) as Spathognathodus primus densidentatus was not synonymized with Helfrich’s elements by the author.

More recent work identifying elements of similar morphology includes Jeppsson et al.

(1994), in which the authors (incl. Viira) do consider the subspecies of Helfrich (1975) and Viira (1983) to be conspecific, and identified it as Ozarkodina confluens densidentata. Jeppsson et al. (1994) illustrated an element from the Klinteberg beds on

Gotland, which they indicate are Homerian. The element from the Klinteberg beds does not have the same distinctive aboral margin as the elements of Helfrich nor the element imaged herein. It would seem that this morphology is a recurring one, but the variation in morphology and occurrence timing suggest that the element illustrated in Jeppsson et al. 57

(1994) is different from those in Helfrich (1975), and that the element from Duff Quarry

(10MK2-33, Plate 4 # 5) resembles the earlier paper’s specimen.

Con Ag Quarry

Elements of the genus Panderodus in samples from Con Ag Quarry include a possible candidate for P. greenlandensis, but on the whole the panderodid coniforms are bent to between 40º and 70º and do not have a serrated inner edge, leaving few useful characters.

Pseudooneotodus beckmanni comes to a very sharp single point and is easily identifiable within this genus. Later forms with specific morphologic characters include

Pseudooneotodus bicornis and Pseudooneotodus linguicornis, both of which were recovered and are imaged on Plate 4 (specimens 11 and 12 respectively).

Pseudooneotodus bicornis has a tip that diverges slightly into two nodes, and

Pseudooneotodus linguicornis has a single tip that grows wider than P. beckmanni but curves over. P. linguicornis has been shown to become extinct at Datum 1.5 of the

Mulde Event in Gotland and be restricted to the Ozarkodina sagitta sagitta Zone and

Subzone 0 of the Ozarkodina bohemica longa Zone (Calner and Jeppsson 2003).

HA7 Core

For the most part the Ozarkodina confluens Pa elements in this core were fairly typical of the species, with the prominent cockscomb (raised denticles) at the anterior end, some angling of cusp and posterior denticles toward the posterior, and a small

58

normally central basal cavity. Occasional fusing of denticles in larger specimens is observed.

A single juvenile Pa element likely belonging to the genus Kockelella was recovered from sample HA7-177 (95 m below HA7-93) and is imaged in Plate 4, figure

10. Both the anterior and posterior portions of the blade are broken away and the element is too small to image effectively laterally. Small developing nodes on the platform of the element are good signs of Kockelella affinity, but the nodes are not developed enough to be sure of the species. The two best candidates are K. stauros and K. amsdeni, both of which develop distinct lateral processes that meet the blade in the center of the basal platform. There is no posterior blade on Pa elements of the latter, whereas Pa elements of the former do have a short posterior blade consisting of three to five denticles (Barrick and Klapper, 1976). K. stauros has a subtriangular basal cavity, whereas K. amsdeni has a more circular basal cavity (Barrick and Klapper, 1976). Although the posterior blade is broken on the juvenile Pa element, it appears to be broken just posterior of the large slightly triangular basal cavity. Only Pa elements of K. stauros have a posterior blade and a subtriangular basal cavity, thereby the juvenile Pa element most likely belongs to that species of Kockelella.

59

Appendix B: Conodont Processing Data

The total number of elements is listed, along with the number of those that are fragments

(pieces of elements that are identifiable to genus level at best). e/kg is elements per kilogram, including fragments.

Table 1 - Conodont retrieval data from the HA7 Core

Section # Elements Fragments Total kg Yield e/kg HA7 93 0 1.6 0.00 HA7 94 4 4 >1 HA7 95 50 47 >1 HA7 96 2 2 1.9 1.05 HA7 97 0 2.1 0.00 HA7 98 3 3 2.2 1.36 HA7 99 14 12 1 14.00 HA7 100 0 2.2 0.00 HA7 101 0 2 0.00 HA7 102 0 2.1 0.00 HA7 103 1 0 1 1.00 HA7 104 2 2 1.55 1.29 HA7 105 1 1 2.15 0.47 HA7 106 3 3 3 1.00 HA7 107 1 1 3.05 0.33 HA7 108 2 0 1.5 1.33 HA7 109 0 2.85 0.00 HA7 110 0 4.45 0.00 HA7 111 0 4.4 0.00 HA7 112 0 4.2 0.00 HA7 113 5 5 4.2 1.19 HA7 114 0 2.9 0.00 HA7 115 1 0 4.2 0.24 HA7 116 3 0 2.7 1.11 HA7 117 2 2 2.5 0.80 HA7 118 1 0 2.4 0.42 HA7 119 2 1 1 2.00

60

HA7 120 10 8 1 10.00 HA7 121 13 7 3.7 3.51 HA7 122 0 4.7 0.00 HA7 123 0 5.35 0.00 HA7 124 5 4 2.4 2.08 HA7 125 1 0 4.4 0.23 HA7 126 0 9.55 0.00 HA7 127 1 1 3 0.33 HA7 128 2 2 1.8 1.11 HA7 129 0 6.05 0.00 HA7 130 0 4.6 0.00 HA7 131 0 3.75 0.00 HA7 132 2 1 3.3 0.61 HA7 133 0 3.5 0.00 HA7 134 0 4 0.00 HA7 135 0 4.1 0.00 HA7 136 0 4 0.00 HA7 137 0 4.25 0.00 HA7 138 0 2.95 0.00 HA7 139 3 1 1 3.00 HA7 140 0 2.2 0.00 HA7 141 6 5 2.3 2.61 HA7 142 20 11 3.55 5.63 HA7 143 40 16 >1 HA7 144 7 4 3.7 1.89 HA7 145 17 10 >1 HA7 146 13 9 1 13.00 HA7 147 23 18 1 23.00 HA7 148 12 7 >1 HA7 149 33 25 >1 HA7 150 2 2 1 2.00 HA7 151 2 1 2.2 0.91 HA7 152 0 3.5 0.00 HA7 153 0 3.6 0.00 HA7 154 0 4.2 0.00 HA7 155 2 1 1 2.00 HA7 156 2 0 1.6 1.25 HA7 157 0 1 0.00 HA7 158 0 4.35 0.00 HA7 159 0 5.1 0.00 HA7 160 0 4 0.00 HA7 161 0 3 0.00 HA7 162 0 3.75 0.00 HA7 163 0 4.7 0.00 HA7 164 0 5 0.00 61

HA7 165 0 5 0.00 HA7 166 0 4.2 0.00 HA7 167 0 4.55 0.00 HA7 168 0 4.1 0.00 HA7 169 0 4.5 0.00 HA7 170 0 3.4 0.00 HA7 171 0 2.6 0.00 HA7 172 0 3.45 0.00 HA7 173 0 3.7 0.00 HA7 174 0 4.4 0.00 HA7 175 0 5.25 0.00 HA7 176 0 1 0.00 HA7 177 2 0 1 2.00 HA7 178 0 1 0.00 HA7 179 1 0 1 1.00 HA7 180 0 4.1 0.00 HA7 181 0 3.7 0.00 HA7 182 0 2.9 0.00 HA7 183 1 0 7.8 0.13 HA7 184 0 5.05 0.00 HA7 185 0 1 0.00 HA7 186 0 3.75 0.00 HA7 187 2 0 3.7 0.54 HA7 188 1 0 4 0.25 HA7 189 0 4 0.00 HA7 190 1 0 4.1 0.24 HA7 191 0 4.45 0.00 HA7 192 2 0 3.95 0.51 HA7 193 0 3.9 0.00 HA7 194 3 0 4.35 0.69 HA7 195 1 0 3.5 0.29 HA7 196 0 2.75 0.00 HA7 197 0 2.95 0.00 HA7 198 0 3.1 0.00

62

Duff Quarry

Table 2 - Conodont retrieval data from Duff Quarry strata

Section # Elements Fragments Total kg Yield e/kg 04MK2 0 8 7 7.4 1.08 04MK2 1 95 82 7.2 13.19 04MK2 2 0 7.6 0.00 04MK2 3 172 144 8.2 20.98 04MK2 4 231 201 7.65 30.20

10MK1 4 0 16 0.00 10MK1 7 1 0 16 0.06 10MK1 10 0 16 0.00 10MK1 13 0 16 0.00 10MK1 17 0 16 0.00

10MK2 22 0 20.75 0.00 10MK2 27 52 36 20.3 2.56 10MK2 31 0 16.4 0.00 10MK2 33 62 54 17.5 3.54

10MK5 8 1 1 13.7 0.07 10MK5 11 329 249 14.8 22.23 10MK5 15 113 81 13.6 8.31 10MK5 21 188 95 14.5 12.97 10MK5 24 18 10 15.4 1.17

63

Con Ag Quarry

Table 3 - Conodont retrieval data from Con Ag Quarry strata

Section # Elements Fragments Total kg Yield e/kg 09MK1 1 0 6.5 0.00 09MK1 2 27 1 6.05 4.46 09MK1 3 39 1 8.1 4.81 09MK1 4 94 25 9.4 10.00 09MK1 5 0 10.5 0.00

10MK4 1 72 1 18.6 3.87 10MK4 2 0 19.6 0.00 10MK4 3 0 15.2 0.00 10MK4 4(1) 15 1 5.1 2.94 10MK4 4(2) 24 1 5.3 4.53 10MK4 4(3) 11 1 6.2 1.77 10MK4 5 2 1 20.2 0.10

64

Appendix C: Conodont Distribution Data

Elements were identified to the most specific level possible.

65

Table 4 - Conodont distribution data from Duff Quarry

p. A p.

s B sp. sp.

sp.

.

sp

Pa Ozarkodina PaOzarkodina PaOzarkodina PaOzarkodina Ozarkodina Oulodus Section # Total 10MK1 4 0 10MK1 7 1 1 10MK1 10 0 10MK1 13 0 10MK1 17 0

10MK2 22 0 10MK2 27 14 3 7 17 11 52 10MK2 31 0 10MK2 33 4 23 15 20 62

10MK5 8 1 1 10MK5 11 37 45 61 186 329 10MK5 15 14 27 28 44 113 10MK5 21 28 17 32 111 188 10MK5 24 3 1 5 9 18

04MK2 0 1 1 1 1 4 8 04MK2 1 4 35 14 42 95 04MK2 2 0 04MK2 3 18 70 25 59 172 04MK2 4 16 1 81 9 94 201

66

Table 5 - Conodont distribution data from Con Ag Quarry

sp.

.

sp

sp.

Panderodus Panderodus beckmanni Pseudooneotodus bicornis Pseudooneotodus linguicornis Pseudooneotodus excavata PaOzarkodina PaOzarkodina Ozarkodina Section # Total 09MK1 1 0 09MK1 2 26 1 27 09MK1 3 38 1 39 09MK1 4 43 8 3 4 10 26 94 09MK1 5 0

10MK4 1 71 1 72 10MK4 2 0 10MK4 3 0 10MK4 4(1) 13 1 1 15 10MK4 4(2) 22 2 24 10MK4 4(3) 8 1 1 1 11 10MK4 5 1 1 2

67

Table 6 - Conodont distribution data from the HA7 Core

.

sp

.

.

sp

sp

a sp. a

.

sp

Pa Ozarkodina confluens PaOzarkodina PaOzarkodina Ozarkodina Oulodus snajdri PaOzarkodina longa bohemica PaOzarkodina PaKockelell Panderodus Section # Total HA7 93 0 HA7 94 1 3 4 HA7 95 4 27 17 2 50 HA7 96 2 2 HA7 97 0 HA7 98 3 3 HA7 99 14 14 HA7 100 0 HA7 101 0 HA7 102 0 HA7 103 0 HA7 104 1 1 2 HA7 105 1 1 HA7 106 1 2 3 HA7 107 1 1 HA7 108 2 2 HA7 109 0 HA7 110 0 HA7 111 0 HA7 112 0 HA7 113 5 5 HA7 114 0 HA7 115 1 1 HA7 116 1 2 3 HA7 117 1 1 HA7 118 1 1

68

HA7 119 1 1 2 HA7 120 4 6 10 HA7 121 2 11 13 HA7 122 0 HA7 123 0 HA7 124 3 2 5 HA7 125 1 1 HA7 126 0 HA7 127 1 1 HA7 128 1 1 2 HA7 129 0 HA7 130 0 HA7 131 0 HA7 132 2 2 HA7 133 0 HA7 134 0 HA7 135 0 HA7 136 0 HA7 137 0 HA7 138 0 HA7 139 1 2 3 HA7 140 0 HA7 141 1 5 6 HA7 142 1 1 2 16 20 HA7 143 7 4 20 31 HA7 144 1 1 5 7 HA7 145 1 8 6 15 HA7 146 4 3 7 HA7 147 2 9 9 3 23 HA7 148 6 6 12 HA7 149 2 12 15 4 33 HA7 150 2 2 HA7 151 1 1 2 HA7 152 0 HA7 153 0 HA7 154 0 HA7 155 1 1 HA7 156 1 1 2 HA7 157 0 HA7 158 0

69

HA7 159 0 HA7 160 0 HA7 161 0 HA7 162 0 HA7 163 0 HA7 164 0 HA7 165 0 HA7 166 0 HA7 167 0 HA7 168 0 HA7 169 0 HA7 170 0 HA7 171 0 HA7 172 0 HA7 173 0 HA7 174 0 HA7 175 0 HA7 176 0 HA7 177 1 1 2 HA7 178 0 HA7 179 1 1 HA7 180 0 HA7 181 0 HA7 182 0 HA7 183 1 1 HA7 184 0 HA7 185 0 HA7 186 0 HA7 187 2 2 HA7 188 1 1 HA7 189 0 HA7 190 1 1 HA7 191 0 HA7 192 2 2 HA7 193 0 HA7 194 3 3 HA7 195 1 1 HA7 196 0 HA7 197 0 HA7 198 0

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Appendix D: Locality Information

Data table for localities sampled including UTM coordinates and names used throughout the document.

71

Locality Sample UTM of sampled Total m sampled Processed for Processed for δ13C Locality name: Collected by: Code: locality: and processed: conodonts by: and δ18O by: Indiana Indiana G. S. 16T 655673m E HA7 146.00 MK JB Geological Core HA7 4600752m N Survey

17T 261736m E 04MK2 Duff Quarry 4.90 MK N/A MK 4484500m N

16S 612278mE 08MK2 Anderson Falls 3.40 MK JB MK, WA, BC 4344212mN

16T 721534m E 09MK1 Con Ag Quarry 6.25 MK JB MK, BC 4496974m N

17T 261736m E 10MK1 & 2 Duff Quarry 10.80 MK, RS JB MK, RS 4484500m N

16T 721534m E 10MK3 Con Ag Quarry 15.80 N/A JB MK 4496974m N

16T 721534m E 10MK4 Con Ag Quarry 4.50 MK N/A MK 4496974m N

17T 261736m E 10MK5 Duff Quarry 7.70 MK, RS JB MK, RS 4484500m N

Table 7 : MK – Mark Kleffner, The Ohio State University, Lima OH, 45804; RS – The Author; BC – Brad Cramer, Kansas Geological Survey, Lawrence KS, 66047; WA – William Ausich, The Ohio State University, Columbus OH, 43210; JB – James Barrick, Texas Tech University Stable Isotope Laboratory, Box 41053, Lubbock, Texas 79409

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Appendix E: Data Tables and Cross Plots of Isotopic Analysis Data

09MK1 – Con Ag Quarry

Table 8 - Isotopic analysis data and cross plot from 09MK1 - Con Ag Quarry

Sample # Meters above base δ13C δ18O Formation 17 6.25 2.85 -7.25 Greenfield Dol. 16 6 2.66 -7.85 Greenfield Dol. 15 5.75 2.21 -7.39 Greenfield Dol. 14 5.25 2.03 -7.46 Greenfield Dol. 13 5 1.73 -8.04 Greenfield Dol. 12 4.75 1.5 -7.96 Transitional 11 4.5 -0.73 -7.43 Transitional 10 4.25 0.99 -7.30 Cedarville Dol. 9 4 0.47 -7.43 Cedarville Dol. 8 3.5 0.39 -7.88 Cedarville Dol. 7 3 0.86 -9.13 Cedarville Dol. 6 2.5 0.96 -7.12 Cedarville Dol. 5 2 1.15 -7.49 Cedarville Dol. 4 1.5 0.47 -7.17 Cedarville Dol. 3 1 0.54 -7.42 Cedarville Dol. 2 0.5 0.59 -7.58 Cedarville Dol. 1 0 0.95 -7.67 Cedarville Dol.

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10MK3 - Con Ag Quarry

Table 9 - Isotopic analysis data and cross plot from 10MK3 - Con Ag Quarry core

Sample # Meters below surface δ13C δ18O Formation 60 0 -1.39 -8.18 Greenfield Dol. 59 0.1 -1.07 -8.80 Greenfield Dol. 58 0.4 -1.23 -8.20 Greenfield Dol. 57 0.7 -1.71 -8.29 Greenfield Dol. 56 1.05 -1.6 -8.27 Greenfield Dol. 55 1.15 -1.51 -8.53 Greenfield Dol. 54 1.3 -1.07 -8.80 Greenfield Dol. 53 1.5 -0.97 -7.80 Greenfield Dol. 52 1.8 -0.57 -8.06 Greenfield Dol. 51 2.15 -0.15 -8.28 Greenfield Dol. 50 2.5 0.28 -7.62 Greenfield Dol. 49 2.75 0.54 -7.30 Greenfield Dol. 48 3 0.72 -7.15 Greenfield Dol. 47 3.3 0.62 -7.42 Greenfield Dol. 46 3.65 0.57 -7.62 Greenfield Dol. 45 3.9 0.48 -8.00 Greenfield Dol. 44 4.15 1.1 -7.27 Greenfield Dol. 43 4.4 1.26 -7.25 Greenfield Dol. 42 4.6 1.2 -7.47 Greenfield Dol. 41 4.9 1.26 -7.59 Greenfield Dol. 40 5.1 1.34 -7.42 Greenfield Dol. 39 5.4 1.41 -7.32 Greenfield Dol. 38 5.7 1.49 -7.20 Greenfield Dol. 37 6 1.03 -7.63 Greenfield Dol. 36 6.25 0.9 -7.65 Greenfield Dol. 35 6.5 1 -7.66 Greenfield Dol. 34 6.8 1.04 -7.25 Greenfield Dol. 33 7.1 1.1 -7.34 Greenfield Dol. 32 7.4 1.04 -7.38 Greenfield Dol. 31 7.6 1.02 -7.66 Greenfield Dol. 30 7.9 1.46 -7.30 Greenfield Dol. 29 8.15 1.55 -7.44 Greenfield Dol. 28 8.4 2.3 -7.41 Greenfield Dol. 27 8.6 2.16 -7.51 Greenfield Dol. 26 8.9 2 -7.73 Greenfield Dol. 25 9.1 2.06 -7.73 Greenfield Dol. 24 9.45 2.59 -7.23 Greenfield Dol. 23 9.65 2.2 -7.45 Greenfield Dol. 22 9.85 2.12 -7.48 Greenfield Dol. 21 10.2 2 -7.55 Greenfield Dol. 20 10.5 1.94 -7.58 Greenfield Dol. 19 10.9 2.02 -7.47 Greenfield Dol. 18 11.25 1.98 -7.53 Greenfield Dol. 17 11.72 Greenfield Dol. 16 12 1.04 -8.14 Transitional 15 12.03 1.3 -7.70 Transitional 14 12.06 1.36 -7.73 Transitional 13 12.3 0.95 -7.68 Cedarville Dol. 12 12.5 0.82 -7.88 Cedarville Dol. 74

11 12.8 0.63 -8.00 Cedarville Dol. 10 13.1 0.69 -7.85 Cedarville Dol. 9 13.55 0.51 -7.93 Cedarville Dol. 8 13.8 0.44 -7.96 Cedarville Dol. 7 14.15 0.12 -8.09 Cedarville Dol. 6 14.5 0.12 -7.97 Cedarville Dol. 5 14.75 0.29 -7.77 Cedarville Dol. 4 14.95 0.33 -7.69 Cedarville Dol. 3 15.2 0.41 -7.93 Cedarville Dol. 2 15.5 -0.09 -8.06 Cedarville Dol. 1 15.8 0.01 -8.25 Cedarville Dol.

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10MK1/2 – Duff Quarry

Table 10 - Isotopic analysis data and cross plot from 10MK1/2 – Duff Quarry

Section Sample # m above base δ13C δ 18O 10MK1- 17 1080 -0.161 -7.84 10MK1- 16 990 -0.53 -7.79 10MK1- 15 960 -0.73 -8.1 10MK1- 14 920 -0.68 -7.85 10MK1- 13 890 -0.35 -7.44 10MK1- 12 860 -0.337 -7.55 10MK1- 11 820 -0.208 -7.96 10MK1- 10 790 -0.37 -7.97 10MK1- 9 760 -0.77 -8.03 10MK1- 8 720 -0.91 -7.3 10MK1- 7 690 -1.24 -7.48 10MK1- 6 660 -1.03 -7.37 10MK1- 5 620 -0.94 -7.7 10MK1- 4 590 -0.91 -7.63 10MK1- 3 560 -0.58 -7.8 10MK1- 2 520 -0.43 -7.72 10MK2- 33 500 -0.543 -7.69 10MK1- 1 490 -0.4 -7.83 10MK2- 32 480 -0.777 -7.56 10MK2- 31 430 -0.28 -7.73 10MK2- 30 400 -0.066 -7.57 10MK2- 29 370 -0.031 -7.46 10MK2- 28 330 -0.031 -7.62 10MK2- 27 300 -0.699 -7.7 10MK2- 26 270 -1.155 -7.69 10MK2- 25 230 -1.047 -8.1 10MK2- 24 200 -0.907 -7.87 10MK2- 23 170 -0.534 -7.59 10MK2- 22 120 -0.5 -7.82 10MK2- 21 100 -0.679 -8.02 10MK2- 20 70 -0.729 -7.99 10MK2- 19 30 -0.71 -8.06 10MK2- 18 0 -0.319 -7.66

76

77

10MK5 – Duff Quarry

Table 11 - Isotopic analysis data and cross plot from 10MK5 - Duff Quarry

Sample #s 10MK5- m above base δ13C δ 18O 24 7.70 -0.737 -7.774 23 7.30 -0.793 -7.577 22 7.00 -0.788 -7.445 21 6.70 -1.08 -7.441 20 6.30 -1.698 -7.441 19 6.00 -1.728 -7.407 18 5.60 -1.482 -7.468 17 5.30 -1.516 -7.248 16 5.00 -1.351 -7.385 15 4.60 -1.857 -7.375 14 4.30 -1.159 -7.505 13 4.00 -0.683 -7.649 12 3.60 -0.391 -7.418 11 3.30 -0.55 -7.617 10 3.00 -0.408 -7.539 9 2.60 -0.365 -7.549 8 2.30 -0.527 -7.599 7 2.00 -0.396 -7.364 6 1.60 -0.318 -7.471 5 1.30 -0.658 -7.674 4 1.00 -0.675 -7.671 3 0.60 -0.462 -7.743 2 0.30 -0.094 -7.706 1 0.00 0.05 -7.514

78

08MK2 – Anderson Falls

Table 12 - Isotopic analysis data and cross plot from 08MK2 - Anderson Falls

Meters above base δ13C δ18O Formation 2.9 2.17 -2.55 Jeffersonville Dol. 2.8 1.79 -3.74 Jeffersonville Dol. 2.7 2.16 -2.88 Jeffersonville Dol. 2.6 2.22 -3.03 Jeffersonville Dol. 2.5 3.76 -0.16 Waldron Member 2.4 3.21 -1.58 Waldron Member 2.3 3.24 -1.17 Waldron Member 2.2 3.48 -1.08 Waldron Member 2.1 3.48 -0.43 Waldron Member 2.0 3.51 -0.58 Waldron Member 1.9 3.38 -0.67 Waldron Member 1.8 4.76 1.62 Waldron Member 1.7 3.67 -1.25 Waldron Member 1.6 3.46 -1.01 Waldron Member 1.5 2.85 -2.44 Waldron Member 1.4 3.11 -2.52 Waldron Member 1.3 3.02 -2.65 Waldron Member 1.2 3.07 -2.12 Waldron Member 1.1 3.1 -2.70 Waldron Member 1.0 3.82 -2.51 Waldron Member 0.9 2.82 -4.05 Waldron Member 0.8 2.78 -4.20 Waldron Member 0.7 2.85 -2.44 Waldron Member 0.6 2.09 -4.34 Waldron Member 0.5 2.04 -4.48 Waldron Member 0.4 1.7 -4.34 Waldron Member 0.3 1.8 -4.55 Waldron Member 0.2 1.9 -4.30 Waldron Member 0.1 1.78 -4.03 Waldron Member 0.0 2.46 -3.32 Waldron Member -0.5 2.76 -2.3 Laurel Member

79

80

HA7 Core

Table 13 - Isotopic analysis data and cross plot from HA7 Core

HA7 Sample # Depth of sample δ13C δ18O (m below HA7-93) 93 0.00 -0.74 -6.11 94 0.61 95 0.91 96 1.52 -0.39 -5.71 97 2.13 -0.66 -5.53 98 2.74 -0.81 -5.70 99 3.65 -0.9 -6.23 100 4.26 -0.75 -5.90 101 4.87 -0.83 -5.57 102 5.79 -0.89 -5.32 103 6.09 0.65 -5.93 104 6.70 -0.28 -6.31 105 7.31 -0.6 -5.79 106 8.23 -0.53 -6.34 107 9.44 -0.56 -5.41 108 10.66 -0.24 -6.49 109 11.88 0.12 -5.44 110 13.10 111 14.32 0.27 -5.95 112 15.54 0.48 -5.39 113 16.76 -0.2 -5.94 114 17.98 0.03 -5.87 115 19.20 -0.31 -5.82 116 20.42 -0.69 -7.07 117 21.64 -0.35 -6.48 118 22.86 -0.38 -6.21 119 24.08 -0.19 -5.93 120 25.29 -0.38 -6.01 121 26.51 -0.6 -5.98 122 27.73 0.12 -6.17 123 28.95 0.11 -6.44 124 30.17 0.02 -6.79 125 31.39 0.36 -6.98 126 32.61 2.63 -7.83 127 33.83 0.32 -6.79 128 35.05 0.5 -7.68 129 36.27 0.63 -6.92 130 37.49 0.66 -8.00 131 38.71 0.25 -6.73 132 39.92 0.63 -8.55 133 40.84 0.52 -8.19 134 42.06 0.75 -8.54 135 43.28 0.82 -8.07 136 44.50 0.72 -8.24 137 45.72 0.85 -8.45 138 46.63 0.88 -8.19 139 47.54 0.81 -8.00 140 48.15 0.8 -7.14 141 49.37 0.6 -8.70

81

142 48.46 0.59 -8.10 143 49.68 144 50.90 0.51 -8.36 145 52.12 146 53.03 0.56 -8.61 147 53.95 0.58 -9.89 148 54.86 149 56.08 150 57.30 -0.12 -7.56 151 58.52 0.15 -7.50 152 59.74 0.3 -7.74 153 60.96 -0.08 -7.39 154 62.18 -0.29 -7.11 155 63.39 -0.21 -7.42 156 64.61 0.74 -8.46 157 65.83 0.49 -6.84 158 72.54 2.31 -8.25 159 73.76 2.39 -8.71 160 74.98 2.2 -7.94 161 76.20 2.41 -7.68 162 77.42 2.42 -8.31 163 78.63 2.4 -5.73 164 79.85 2.52 -7.33 165 81.07 2.93 -8.13 166 82.29 3.08 -8.17 167 83.51 3.15 -8.62 168 84.73 2.29 -7.77 169 85.95 2.84 -7.82 170 87.17 3.1 -7.95 171 87.78 3.19 -8.33 172 88.69 3.23 -9.17 173 89.91 3.35 -8.11 174 91.13 3.34 -8.18 175 176 177 94.79 3.14 -8.80 178 179 97.23 2.94 -8.54 180 98.45 3.41 -8.77 181 99.67 3.33 -8.59 182 100.88 3.38 -7.11 183 102.10 2.83 -7.03 184 185 186 105.76 1.49 -8.92 187 106.98 1.02 -7.22 188 107.90 0.9 -7.20 189 108.81 1.09 -8.48 190 110.03 0.9 -8.65 191 111.25 0.94 -9.22 192 112.47 1.06 -9.27 193 113.69 0.84 -9.25 194 114.91 0.84 -9.32 195 116.12 0.74 -8.88 196 117.04 0.58 -9.12 197 117.95 0.7 -8.76 198 118.87 0.77 -9.25 199 119.78 1.14 -8.02 82

200 121.00 1.09 -7.71 201 122.22 1.22 -7.19 202 123.44 1.19 -7.47 203 124.66 1.3 -7.2 204 125.88 1.22 -7.39 205 127.10 1.23 -8.02 206 128.32 1.28 -8.02 207 129.54 1.24 -6.75 208 130.76 1.27 -8.02 209 131.97 1.09 -9.25 210 133.19 1.27 -7.81 211 134.41 1.3 -8.02 212 135.63 1.17 -8.02 213 136.85 1.21 -7.81 214 138.07 1.19 -7.42 215 139.29 0.93 -7.96 216 140.51 1.02 -8.05 217 141.73 1 -7.81 218 142.95 1.03 -7.97 219 144.17 0.93 -8.02 220 145.39 1.03 -8.05 221 146.60 1.1 -7.14

83

84

Appendix F: Details from 10MK3 Core

85

Figure 11 - Representative portion of 16 m – 12 m depth in the 10MK3 core. Note stylolites and vugs, some of biogenic origin. 86

Figure 12 - Transition zone (~12m deep in 10MK3 core) from massive dolomite to more well-bedded argillaceous dolomite (interpreted as Cedarville - Greenfield boundary). Older core on left, younger on right. 87

Figure 13 - 9.3m below ground surface in core. Note circular marks, possibly biogenic.

88

Figure 14 - 8.6m below ground surface in core. Associated apparent jump in isotopes is suggestive of time gaps in deposition.

89

Figure 15 - 4.2 m below ground surface in core. Thick dark band in center appears to overly biogenic/stromatolitic structures.

90

Figure 16 - 1.3m below ground surface in core. Return to vuggy carbonate.

91