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Paleoecology of the Lower Devonian Esopus and Carlisle Center Formations (Tristates Group) of New York State

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Paleoecology of the Lower Devonian Esopus and Carlisle Center Formations (Tristates Group) of New York State PALEOECOLOGY OF THE LOWER DEVONIAN ESOPUS AND CARLISLE CENTER FORMATIONS (TRISTATES GROUP) OF NEW YORK STATE Michael D. Senglaub A Thesis Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 2004 Committee: Margaret M. Yacobucci, Advisor Don C. Steinker © 2004 Michael D. Senglaub All Rights Reserved iii ABSTRACT Margaret M. Yacobucci, Advisor The Lower Devonian Esopus and Carlisle Center Formations of New York State are famous for their abundant Zoophycos and lack of other fossils. The goals of this study were to determine the paleoenvironment during the deposition of the Esopus and Carlisle Center Formations, to document any fossils present, and describe any interactions between the trace-makers and other animals. Numerous fossils are actually present in the Esopus and Carlisle Center Formations, including sponges, conulariids, articulate and inarticulate brachiopods, dacryoconarids, ostracodes, conodonts, and fish bones. Associated with some Zoophycos are Chondrites-like burrows. Chondrites trace-makers may have used Zoophycos traces as a food source. Assuming a larger, better-fed, trace-making animal will make larger feeding structures, Zoophycos size may be used as a paleoenvironmental indicator. Measurements were made of 312 Zoophycos web radii and 231 meniscus heights from several localities, and compared to data from the Green Pond Outlier collected by Marintsch and Finks in 1978. Zoophycos from the Carlisle Center Formation are consistently larger than those from the Green Pond Outlier, likely because the Green Pond Outlier represents shallower water than the Carlisle Center Formation. Small (~10cm wide) unbioturbated lenses are described from the Carlisle Center Formation. These lenses have Zoophycos around them but not within them, and contain a concentration of carbonate fossils. The lenses appear to be gutter casts, filled with iv material transported by storm currents. Calcium phosphate skeletal elements otherwise predominate within the Carlisle Center Formation. It is likely that there is a preservational bias for calcium phosphate and against calcium carbonate, possibly due to the extensive bioturbation in this interval. Since the bioturbators did not enter the gutter casts, the shelly fossils within them were preserved. From the presence of glauconite, Zoophycos, and gutter casts (but no tempestite deposits), a water depth of 60 to 100m can be inferred for the Carlisle Center Formation. The Esopus Formation represents somewhat deeper water. The presence of glauconite and Zoophycos also indicate that the Carlisle Center Formation had a low sedimentation rate, and was slightly dysoxic. The Carlisle Center Formation does contain fossils, although many are likely transported or pelagic in origin. v ACKNOWLEDGMENTS I would like to thank my advisor, Dr. Yacobucci, for her guidance in the field, laboratory, and as an editor. Without her insight and counsel this project would not be completed. I also thank Dr. Steinker for his guidance and editorial contributions to this thesis. I would also like to thank Dr. Evans for his counsel during the development of this thesis. My appreciation goes out to my family for their constant support and even a small field trip for me. I thank Dr. Carl Brett, of the University of Cincinnati, and Dr. Charles Ver Straeten, of the New York State Museum, for their help in the initial stages of this study. I am extremely grateful for the support from the Geology Foundation. I am grateful for the help of Bill Butcher in the photo and computer lab. I appreciate the help that Pat Wilhelm, the BGSU Geology Department secretary, gave me on almost a daily basis. I would be lost without her. Finally, I would also like to thank Dr. James Ebert of the State University of New York, College at Oneonta for spurring the interest in studying this interval within me. vi TABLE OF CONTENTS Page INTRODUCTION ..................................................................................................... 1 Regional Setting............................................................................................. 1 Lower Devonian Stratigraphy........................................................................ 3 OBJECTIVES……………........................................................................................ 9 METHODS…………. ............................................................................................... 9 Field Work….. ............................................................................................... 9 Laboratory Work............................................................................................ 11 Thin Sections..................................................................................... 11 Polished Sections............................................................................... 12 Conodont Extraction.......................................................................... 13 Fossil Preparation and Identification ................................................. 14 STRATIGRAPHY AND GENERAL PALEONTOLOGY....................................... 14 Esopus Formation .......................................................................................... 14 Stratigraphy........................................................................................ 14 Polished Section Descriptions............................................... 16 Fauna….............................................................................................. 21 Faunal Descriptions............................................................... 21 Carlisle Center Formation.............................................................................. 26 Stratigraphy........................................................................................ 26 Thin Section Descriptions...................................................... 29 Polished Section Descriptions............................................... 49 Fauna….............................................................................................. 54 vii Sponges.................................................................................. 54 Description................................................................. 54 Interpretation.............................................................. 54 Conulariids............................................................................. 56 Descriptions ............................................................... 56 Interpretations ............................................................ 59 Brachiopods ........................................................................... 61 Descriptions ............................................................... 61 Interpretations ............................................................ 64 Dacryoconarids ...................................................................... 66 Description................................................................. 66 Interpretations ............................................................ 66 Ostracodes.............................................................................. 67 Descriptions ............................................................... 67 Interpretations ............................................................ 69 Holothurians........................................................................... 70 Description................................................................. 70 Interpretations ............................................................ 70 Chordates ............................................................................... 73 Descriptions ............................................................... 73 Interpretations ............................................................ 73 Trace Fossils.......................................................................... 76 Descriptions ............................................................... 76 Interpretations ............................................................ 80 viii THE PALEOENVIRONMENTAL AND PALEOECOLOGICAL SIGNIFICANCE OF ZOOPHYCOS ……………….................................................................................... 82 Ichnology Background................................................................................... 82 Ichnology Basics................................................................................ 82 Ichnofacies Concept........................................................................... 84 The Zoophycos Trace Fossil .......................................................................... 84 Zoophycos: Two Views...................................................................... 86 Size as an Indicator of Environmental Quality.............................................. 88 Supporting Evidence.......................................................................... 91 Web Radii.............................................................................. 91 Meniscus Heights................................................................... 104 THE PALEOENVIRONMENTAL SIGNIFICANCE OF GLAUCONITE.............. 111 Glauconite: the Mineral ................................................................................. 111 Glauconite: Habits .................................................................................... 112 Environment of Glauconitization..................................................................
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