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Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs Amanda Colleen Lough Washington University in St

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Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs Amanda Colleen Lough Washington University in St Washington University in St. Louis Washington University Open Scholarship All Theses and Dissertations (ETDs) Summer 9-1-2014 Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs Amanda Colleen Lough Washington University in St. Louis Follow this and additional works at: https://openscholarship.wustl.edu/etd Recommended Citation Lough, Amanda Colleen, "Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs" (2014). All Theses and Dissertations (ETDs). 1319. https://openscholarship.wustl.edu/etd/1319 This Dissertation is brought to you for free and open access by Washington University Open Scholarship. It has been accepted for inclusion in All Theses and Dissertations (ETDs) by an authorized administrator of Washington University Open Scholarship. For more information, please contact [email protected]. WASHINGTON UNIVERSITY IN ST. LOUIS Department of Earth and Planetary Sciences Dissertation Examination Committee: Douglas Wiens, Chair Jill Pasteris Philip Skemer Viatcheslav Solomatov Linda Warren Michael Wysession Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs by Amanda Colleen Lough A dissertation presented to the Graduate School of Arts and Sciences of Washington University in partial fulfillment of the requirements for the degree of Doctor of Philosophy August 2014 St. Louis, Missouri © 2014, Amanda Colleen Lough Table of Contents List of Figures .............................................................................................................................. viii List of Tables ................................................................................................................................. ix Acknowledgments........................................................................................................................... x ABSTRACT OF THE DISSERTATION .................................................................................... xiv Chapter 1: Introduction ................................................................................................................. 1 References ................................................................................................................................... 4 Chapter 2: Seismicity of Antarctica .............................................................................................. 5 Abstract ....................................................................................................................................... 5 2.1 Introduction .......................................................................................................................... 6 2.1.1 Geology of Antarctica ..................................................................................................... 8 2.1.2 Previous Work ............................................................................................................... 9 2.1.3 Known Types of Seismicity .......................................................................................... 13 2.2 Data .................................................................................................................................... 15 2.2.1 Data Collection............................................................................................................ 15 2.2.2 Data Quality ................................................................................................................ 17 ii 2.2.3 Additional Data ........................................................................................................... 18 2.3 Methods .............................................................................................................................. 18 2.3.1 High Frequency Event Detection ................................................................................ 18 2.3.2 High Frequency Event Location .................................................................................. 19 2.3.3 Low Frequency Event Detection and Location ........................................................... 21 2.4. Results ................................................................................................................................ 24 2.4.1 High Frequency ........................................................................................................... 24 2.4.2 Low Frequency ............................................................................................................. 25 2.5 Discussion .......................................................................................................................... 27 2.5.1 Vanderford Glacier Seismicity .................................................................................... 27 2.5.2 Other Coastal Events ................................................................................................... 30 2.5.3 Transantarctic Mountains ............................................................................................ 32 2.5.4 East Antarctic Craton .................................................................................................. 33 2.5.5 West Antarctica............................................................................................................. 37 2.6 Conclusions ......................................................................................................................... 40 References ................................................................................................................................. 42 Figure Captions ......................................................................................................................... 55 iii Table Legends ........................................................................................................................... 57 Figures ....................................................................................................................................... 58 Tables ........................................................................................................................................ 74 Chapter 3: Seismic Detection of an Active Subglacial Magmatic Complex .............................. 79 in Marie Byrd Land, Antarctica .................................................................................................... 79 Abstract ..................................................................................................................................... 79 3.1 Introduction ......................................................................................................................... 80 3.2 Results ................................................................................................................................. 81 3.3 Discussion ........................................................................................................................... 83 3.4 Conclusion ........................................................................................................................... 86 S3.0 Supplemental Materials..................................................................................................... 88 S3.1 Methods ............................................................................................................................. 88 S3.1.1 Data Collection........................................................................................................... 88 S3.1.2 Data Analysis .............................................................................................................. 88 S3.2 Event Statistics .................................................................................................................. 89 S3.3 Local Model ...................................................................................................................... 90 iv S3.4 Depth Testing .................................................................................................................... 90 S3.5 Cross Correlation .............................................................................................................. 90 S3.6 Eruptive Energy Calculation ............................................................................................. 91 S3.7 Volume Ice Melted Calculation ........................................................................................ 92 References ................................................................................................................................. 93 Figure Captions ....................................................................................................................... 101 Table Legends ......................................................................................................................... 103 Figures ..................................................................................................................................... 104 Tables ...................................................................................................................................... 113 Chapter 4: A New Type of Seismic Source in the Firn Layer of the ........................................ 116 East Antarctic Ice Sheet .............................................................................................................. 116 Abstract ..................................................................................................................................
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