A Comprehensive Analysis of Vibracores from St
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Georgia State University ScholarWorks @ Georgia State University Geosciences Theses Department of Geosciences 5-10-2014 Enhancing Georgia's Paleohurricane Record: A Comprehensive Analysis of Vibracores from St. Catherines Island Erick Braun Follow this and additional works at: https://scholarworks.gsu.edu/geosciences_theses Recommended Citation Braun, Erick, "Enhancing Georgia's Paleohurricane Record: A Comprehensive Analysis of Vibracores from St. Catherines Island." Thesis, Georgia State University, 2014. https://scholarworks.gsu.edu/geosciences_theses/69 This Thesis is brought to you for free and open access by the Department of Geosciences at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Geosciences Theses by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact [email protected]. ENHANCING GEORGIA’S PALEOHURRICANE RECORD: A COMPREHENSIVE ANALYSIS OF VIBRACORES FROM ST. CATHERINES ISLAND by ERICK BRAUN Under the Direction of Dr. Lawrence M. Kiage ABSTRACT Hurricanes are amongst the most devastating of the world’s natural disasters and can cause bil- lions of dollars’ worth of damage every year. Efforts to predict where and when tropical cyclones might strike, then, could potentially save money and lives. A lack of data exists for the GA coast, and the future direction of climate change could potentially bring more hurricanes to the state. This study provides in- formation to enhance the paleohurricane record by examining three vibracores drawn from St. Catherines Island, GA. After interpreting the environments that generated the sediment found in one of these cores and corroborating evidence from the additional cores, six potential hurricane events were discovered, five of which were likely major hurricanes, category 3 or higher. Magnitudes were deter- mined by comparison to event six, thought to be “The Great Gale of 1804”, a major hurricane recorded by the sedimentary record of St. Catherines Island. INDEX WORDS: Paleotempestology, St. Catherines Island, Paleohurricanes, LOI, XRF, Foraminifera ENHANCING GEORGIA’S PALEOHURRICANE RECORD: A COMPREHENSIVE ANALYSIS OF VIBRACORES FROM ST. CATHERINES ISLAND by ERICK BRAUN A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in the College of Arts and Sciences Georgia State University 2013 Copyright by Erick Claude Braun 2013 ENHANCING GEORGIA’S PALEOHURRICANE RECORD: A COMPREHENSIVE ANALYSIS OF VIBRACORES FROM ST. CATHERINES ISLAND by ERICK BRAUN Committee Chair: Lawrence Kiage Committee: Daniel Deocampo Christy Visaggi Electronic Version Approved: Office of Graduate Studies College of Arts and Sciences Georgia State University December 2013 iv DEDICATION I dedicate this thesis to Simmone Simpson, who helped me stay sane through the course of my Masters program, provided endless support, hours of fun, and even joined me at Georgia State for grad- uate study. I could not ask for a more perfect and supportive friend. v ACKNOWLEDGEMENTS I would first like to thank Dr. Lawrence Kiage for providing me with an interesting focus and pro- ject for my graduate studies, as well as for granting me the necessary funds to embark on this journey. I would also like to thank my committee members Dr. Christy Visaggi and Dr. Daniel Deocampo for their time and equipment, as well as Georgia State University’s Department of Geosciences for providing funding through a teaching assistantship. I am also grateful for the support of Dr. Brian Meyer for the use of his vibracoring equipment and professional consultation regarding environments present on St. Catherines Island. Special thanks to Amber Keller who greatly assisted me in the LOI process and Daniel McCartha, who helped me do everything from saw open cores to understanding the basic processes for processing Foraminifera for examination. vi TABLE OF CONTENTS ACKNOWLEDGEMENTS .......................................................................................................... v LIST OF TABLES ..................................................................................................................... ix LIST OF FIGURES ..................................................................................................................... x 1 INTRODUCTION ...............................................................................................................1 1.1 The Atlantic Tropical Storm Database .......................................................................2 1.2 The Sedimentary Record ..........................................................................................3 1.2.1 Overwash Deposits ..............................................................................................3 1.2.2 Site Selection .......................................................................................................4 1.2.3 Coring .................................................................................................................4 1.2.4 Sediment Identification........................................................................................5 1.2.5 Calibration or Modern Analogue ..........................................................................9 1.2.6 Establishing the Chronology ............................................................................... 10 1.3 Historical Documentation ....................................................................................... 10 1.4 Hurricane Forecasting ............................................................................................. 12 1.5 Climate Change ...................................................................................................... 15 1.6 Research Questions and Objectives ........................................................................ 17 2 STUDY AREA .................................................................................................................. 18 3 METHODS ...................................................................................................................... 21 3.1 Data Collection ....................................................................................................... 21 3.2 Loss On Ignition (LOI) Analyses ............................................................................... 24 vii 3.3 X-ray Fluorescence Spectroscopy ............................................................................ 24 3.4 Foraminiferal Analysis ............................................................................................ 25 3.5 AMS C-14 Dating .................................................................................................... 26 4 RESULTS ........................................................................................................................ 26 4.1 The Chronology ...................................................................................................... 26 4.2 SCVC 01.................................................................................................................. 29 4.3 SCVC 02.................................................................................................................. 31 4.4 SCVC 03.................................................................................................................. 33 5 DISCUSSION................................................................................................................... 41 5.1 Environmental Regimes .......................................................................................... 43 5.1.1 Regime A and E ................................................................................................. 43 5.1.2 Regime B ........................................................................................................... 44 5.1.3 Regime C ........................................................................................................... 45 5.1.4 Regime D .......................................................................................................... 46 5.1.5 Sea Level/Deposition of St. Catherines Island ..................................................... 47 5.2 Potential Paleohurricane Events ............................................................................. 48 5.2.1 Event 1 ............................................................................................................. 51 5.2.2 Event 2 ............................................................................................................. 52 5.2.3 Event 3 .............................................................................................................. 54 5.2.4 Event 4 .............................................................................................................. 55 viii 5.2.5 Event 5 .............................................................................................................. 55 5.2.6 Event 6 .............................................................................................................. 56 5.2.7 Non-Storm Related Anomalies ........................................................................... 57 5.3 Possible Correlation Between SCVC 03 and SCVC 02 ................................................ 58 6 CONCLUSION ................................................................................................................. 61 6.1 Study Overview .....................................................................................................