Conodont Apparatus Reconstruction from the Lower Carboniferous Hart River Formation, Norther Yukon Territory
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University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2016 Conodont Apparatus Reconstruction from the Lower Carboniferous Hart River Formation, Norther Yukon Territory Lanik, Amanda Lanik, A. (2016). Conodont Apparatus Reconstruction from the Lower Carboniferous Hart River Formation, Norther Yukon Territory (Unpublished master's thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/25420 http://hdl.handle.net/11023/3324 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY Conodont Apparatus Reconstruction from the Lower Carboniferous Hart River Formation, Northern Yukon Territory by Amanda Lanik A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE GRADUATE PROGRAM IN GEOLOGY AND GEOPHYSICS CALGARY, ALBERTA SEPTEMBER, 2016 © Amanda Lanik 2016 Abstract Conodonts sampled from the Lower Carboniferous Hart River Formation have yielded abundant, well-preserved elements with a relatively low diversity of species. In addition, they do not display much platform-overrepresentation, a phenomenon affecting the majority of Late Paleozoic conodont samples. These qualities make the Hart River conodont samples ideal for statistical apparatus reconstruction. The elements were divided into groups based on morphology and counted. Cluster analysis, in addition to empirical observations made during the counting process, was then used to reconstruct the original apparatus composition for the species present. Five partial to complete apparatus reconstructions were made, belonging to the species Bispathodus sp. A, Bispathodus stabilis, Gnathodus homopunctatus, Gnathodus texanus, and Vogelgnathus gladiolus. The co-occurrence of these species indicate an early Visean age for the Hart River Formation. This differs slightly from the late Visean to early Serpukhovian age previously suggested for the Hart River Formation. The apparatus reconstructions prompted the reassignment of what has been called Lochriea homopunctatus in previous studies to the genus Gnathodus, and the new identification of Bispathodus sp. A, formerly interpreted as Rachistognathus prolixus. The apparatus reconstructions made in this study show new morphology for taxa that are both stratigraphically and evolutionarily important, indicating greater taxonomic complexity than was previously identified. ii Acknowledgements I would like to acknowledge the assistance of Mickey Horvath, for the preparation of thin sections, Michael Schoel, for help imaging the elements using the Scanning Electron Microscope, and Richard Fontaine, for access to the Hart River samples at the Geological Survey of Canada. I would also like to thank Chad Morgan, Amanda Godbold, Shane Schoepfer and Elinda Dehari, for discussing ideas, editing writing, and moral support throughout this project. Finally, I would like to acknowledge my advisor Charles Henderson, not only for his exceptional guidance, but for introducing me to aspects of conodont research that have sparked my curiosity. iii Table of Contents Abstract ............................................................................................................................... ii Acknowledgements ............................................................................................................ iii Table of Contents ............................................................................................................... iv List of Tables .......................................................................................................................v List of Figures .................................................................................................................... vi CHAPTER ONE: INTRODUCTION ..................................................................................1 1.1 Purpose and overview of study ................................................................................1 1.2 Introduction ................................................................................................................3 1.2.1 Conodont Studies: A Brief History ...................................................................3 1.2.2 Conodont Taphonomy .......................................................................................8 1.2.3 Previous Work .................................................................................................12 1.3 Expanded methods ...................................................................................................13 1.3.1 Creating morphologic groups ..........................................................................13 1.3.2 Counting and Empirical Observations .............................................................14 1.3.3 Thin Section Preparation .................................................................................14 1.3.4 Rarefaction ......................................................................................................14 1.3.5 Cluster Analysis ...............................................................................................15 1.4 Expanded Results .....................................................................................................17 1.4.1 Morphologic groups ........................................................................................17 1.4.2 Element abundance and distribution ...............................................................27 1.4.3 Thin Sections ...................................................................................................28 1.4.4 Empirical Observations ...................................................................................31 1.4.5 Rarefaction ......................................................................................................42 1.4.6 Cluster Analysis ...............................................................................................42 1.4.7 Biostratigraphy and Paleoenvironment ...........................................................45 1.5 Discussion ................................................................................................................49 1.5.1 Combined Cluster Analysis Results: ...............................................................51 1.6 Role of the student ...................................................................................................52 CHAPTER TWO: CONODONT APPARATUS RECONSTRUCTION .........................54 2.1 Introduction ..............................................................................................................54 2.1.1 Study area.— ...................................................................................................59 2.2 Materials and methods .............................................................................................62 2.3 Results ......................................................................................................................65 2.4 Discussion ................................................................................................................66 2.5 Systematic paleontology ..........................................................................................69 2.6 Conclusions ..............................................................................................................93 CHAPTER THREE: MAJOR CONTRIBUTIONS AND FUTURE WORK ...................96 3.1 Major Contributions .................................................................................................96 3.2 Future Work .............................................................................................................97 iv List of Tables Table 1.1: Element type and abundance………………………………………………27 Table 1.2: Thin section descriptions………………………………….……………… 28 Table 2.1: Species and abundance…………………………………………………….62 v List of Figures Figure 1.1: Generalized Ozarkodinid apparatus……………………………………….….9 Figure 1.2: P1 descriptive terminology……………………………………………….… 18 Figure 1.3: P1 descriptive terminology……………………………………………….….19 Figure 1.4: P2 descriptive terminology…………………………………………………..19 Figure 1.5: M descriptive terminology……………………………………………….….20 Figure 1.6: S0 descriptive terminology…………………………………………………..20 Figure 1.7: S descriptive terminology……………………………………………….…..21 Figure 1.8: P1 element types………………………………………………………….….22 Figure 1.9: P2 element types……………………………………………………………..23 Figure 1.10: M element types…………………………………………………………....23 Figure 1.11: S0 element types…………………………………………………………....24 Figure 1.12: S element types…………………………………………………………….25 Figure 1.13: Element types with distribution one ……………………………………....30 Figure 1.14: All elements with distribution one highlighted……………………...…….32 Figure 1.15: Element types with distribution two ………………………………...…….33 Figure 1.16: All elements with distribution two highlighted………………………...….35 Figure 1.17: Element types with distribution three ………………………………….….36 Figure 1.18: All elements with distribution three highlighted………………………….. 38 Figure 1.19: Element types with distribution four …………………………………..….