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Automated Template B: Created by James Nail 2011V2.1 Speleothem strontium concentrations in eogenetic carbonates By Nicole Ridlen A Thesis Submitted to the Faculty of Mississippi State University in Partial Fulfillment of the Requirements for the Degree of Master of Science in Geology in the Department of Geosciences Mississippi State, Mississippi May 2014 Copyright by Nicole Ridlen 2014 Speleothem strontium concentrations in eogenetic carbonates By Nicole Ridlen Approved: ____________________________________ John E. Mylroie (Director of Thesis) ____________________________________ Rinat I. Gabitov (Committee Member) ____________________________________ Brenda L. Kirkland (Committee Member) ____________________________________ Micheal E. Brown (Graduate Coordinator) ____________________________________ R. Gregory Dunaway Professor and Dean College of Arts & Sciences Name: Nicole Ridlen Date of Degree: May 17, 2014 Institution: Mississippi State University Major Field: Geology Major Professor: Dr.John E. Mylroie Title of Study: Speleothem strontium concentrations in eogenetic carbonates Pages in Study: 267 Candidate for Degree of Master of Science Three questions were asked during this research. 1) Does the Sr content of Caribbean speleothems have a direct relationship with the age of the host rock at the time of speleothem precipitation?; 2) do older speleothems contain less Sr than younger speleothems in the same climatic setting?; and 3) will speleothems record the change in Sr concentration of eogenetic carbonates as a faster depletion in climates of higher precipitation as opposed to drier climates? The speleothems and cave rocks in this study were analyzed with various methods in an attempt to understand the rock processes that affect speleothem Sr concentrations. Evidence to support the hypothesis that younger host rock contributes higher concentrations of Sr to speleothems was found in the stalagmites of Curacao while Bahamian stalagmites indicated climatic variations. The results have implications for using stalagmites from relatively young, eogenetic limestone as a proxy for Sr-related paleoclimate data. DEDICATION “Once you make a decision, the universe conspires to make it happen” –Ralph Waldo Emerson This thesis is dedicated to the friends, family and colleagues who have supported my wild and crazy life, the cavers of Chouteau and Kansas City Area grottoes who helped me find my passion in the underground, and my two Siberian huskies that make sure I do not completely lose my sanity. A full list of everyone who contributed to my thesis is in the acknowledgements. Without all of these influences on my life I would likely be living in a cave instead of studying them. ii ACKNOWLEDGEMENTS When I made the decision to seek a graduate degree in geology I came in knowing exactly what I wanted to do. I wanted to do research related to speleothems. As soon as I made that decision it was as if the entire universe was ready to make it happen. When it comes to this study it is no exception. This research was done with the generous support and assistance of many different people. I could not have done it without the universe of people who were there ready to guide me down this path. While it is impossible to name everyone who made this research possible I would like to take the time to acknowledge many who I am indebted to for the lend of their voluminous skills, knowledge, and connections. None of this research would have been possible without the inspiring guidance of Dr. John Mylroie, my advisor. Not only did he take me under his wing as a graduate student knowing I wanted to study what he likes to call “cave cancer” but he helped me find a research project that not only catered to my love of speleothems but also my thirst for doing something out of the ordinary. I could not imagine having a more attentive advisor than Dr. Mylroie and I am certain my colleagues agree. Few advising professors take the time and dedication to their student’s educational quest than him and without his assurance and inspiring enthusiasm none of this would have been possible. The world of academia will lose a great mentor when he retires in this next year. iii My committee has been instrumental in the research process of my thesis. Dr. Jason Polk welcomed me into his lab and enlightened me about the world of speleothem research even though I was working at a different university. He is an incredibly busy man with many projects but still made time for me. I am almost certain he is not human as he sends emails at all hours of the day, indicating he does not need sleep to sustain himself. The guidance of Dr. Polk not only allowed me to head down the right path but gained me access to the wonderful lab at Western Kentucky University. I am indebted to Dr. Polk and I hope that collaborations in the future will allow me to repay his generous assistance. Dr. Rinat Gabitov provided invaluable data for my Curaҫao rock specimens by laser ablation at Rensselaer Polytechnic Institute. He took time during his visit to run my samples at the lab in New York and assisted me in interpreting and understanding this data. Sincere thanks are also given to graduate assistant Micheal Ackerson and Professor Bruce Watson for their assistance at RPI while Dr. Gabitov ran my samples. The interpretation of my rock thin sections would have been impossible without the assistance of Dr. Brenda Kirkland and her wealth of carbonate knowledge. She took time during her sabbatical to provide me with the information necessary to identify the allochems and various properties of the rocks in thin section. The enthusiasm Dr. Kirkland displays for carbonate petrography is inspiring and will aid me in my research for years to come. Much gratitude is extended to the staff at Mississippi State University’s I2AT center for assisting me with the x-ray diffractor machine. I-Wei was especially informative and walked me through every step as I learned to operate the new equipment. iv Their expertise and technology allowed me to interpret the mineralogy of my rock specimens. The Advanced Materials Institute lab at Western Kentucky University was instrumental in obtaining the trace element analysis of my samples. The lab manager, Pauline Norris and her lab assistant Stephanie spent hours showing me how to process the samples and run the ICP-OES. I learned a lot about the equipment through their knowledge and experience. My multiple stays in Kentucky to work at Western Kentucky University would have been difficult without the generosity of soon-to-be Dr. Patricia Kambesis. She allowed me to stay at her place in Cave City and taught me how to properly map caves. Her expertise and dedication to the karst community is invaluable and I am proud to say I was able to work with her. Paul Stokkermans of the Carmabi foundation in Curaҫao was generous enough to arrange our permission to export specimens from his island to the U.S. He has done a lot of work on the island there to preserve the natural beauty and without him the research on Curaҫao would not have been possible. Nancy Albury of Man-O-War Cay took time out of her busy life to drive us around and get into the caves of Abaco. Her love of the Bahamian ecosystem both past and present is inspirational and I hope to continue to keep in touch with her. Jean Pierce and her husband Kris Newman of Long Island, Bahamas were great hosts and allowed us entrance into the cave on their property, Salt Pond. I saw my first wild manatee thanks to Jean and my stay at Grotto Bay will be an experience to remember for a lifetime. v None of this research would have been possible without the generous funding received from the William L. Wilson scholarship awarded by the Karst Waters Institute, the grant received from the Cave Research Foundation, the Erwin Russell fund, and ExxonMobil. If it were not for organizations like these we would not see the advancement in the studies of karst that have been made all these years. It is important to understand the interconnectivity of the world around us and it is wonderful that organizations exist that understand how integral the study of the world underground is to the world we know on the surface. A big thank you goes to Joan Mylroie, aka “Momma Joan,” for teaching me about the world of snorkeling and the finer things in life. We can study fossils all day but until you see a live reef in action it is impossible to appreciate the grand scheme of carbonate deposition. Thanks to my colleagues who helped me with collection in the field, most notably Ryan Travis and Erik Larson for hammering away with at rocks and lugging around the heavy specimens with me from airport to airport. Special thanks to Dr. Jon Sumrall for showing me the best method to cut thin section blanks. There are many more people I would like to thank; Dr. Sally Zellers, Dr. John Nold, and Dr. Gary Krizanich of my undergraduate university for helping me succeed; Melissa Wergeles and Tanya Nevils for being the best friends I could ever have and always understanding and supporting the strange person I am; Claire Babineaux, Kayla Calhoun, Haley Bustin and all of my new friends in Starkville for getting me out of my little box every now and then; And my family back home for supporting me even though they have no idea what I am doing. vi I am sure I missed some great people here and if I did just know I am grateful to each and every one of you. Every person that has touched my life has helped make this possible.