The anisotropy beneath the Southeastern United States: influences of mantle flow and tectonic events
Department
Geosciences and Geological and Petroleum Engineering
Major
Geology and Geophysics
Research Advisor
Gao, Stephen S.
Advisor's Department
Geosciences and Geological and Petroleum Engineering
Funding Source
OURE program
Abstract
The main purpose of the research is to investigate the interior structure beneath the southeastern United States (90°W~75°W, 37°N~24°N) by using the shear-wave-splitting technique, which provides constraints to characterize the mantle flow direction and strength of anisotropy. At most stations, the detected polarization directions of the fast wave are approximately parallel to the absolute plate motion (APM) direction of the North American plate, suggesting a coupling between the asthenosphere and the lithosphere. The similarity between the Appalachian Mountain’s strike and the fast directions, and the significant differences between APM direction and the fast directions at the eastern margin indicate a contribution of anisotropy from lithospheric deformational processes. The splitting time between the fast and slow shear waves, which can be utilized to characterize the strength of anisotropy, shows systematical distribution through the study area. The study confirm the contribution of both fossil fabrics in the lithosphere and present mantle flow in the asthenosphere to the pbserved seismic anisotropy.
Biography
Wanying Wang is a senior majoring in Geology and Geophysics. She is a transfer student who finished the former two years of study in China University of Geosciences. With strong enthusiasm, she found her value in learning to use geophysical techniques to explore the Earth. Wanying gained experiences in projects and presentations focusing on seismology and geodynamics. She is currently a member of Society of Exploration Geophysicists (SEG) and has a published abstract submitted to Geological Society of America (GSA), 2014.
Research Category
Sciences
Presentation Type
Poster Presentation
Document Type
Poster
Location
Upper Atrium/Hall
Presentation Date
16 Apr 2014, 9:00 am - 11:45 am
The anisotropy beneath the Southeastern United States: influences of mantle flow and tectonic events
Upper Atrium/Hall
The main purpose of the research is to investigate the interior structure beneath the southeastern United States (90°W~75°W, 37°N~24°N) by using the shear-wave-splitting technique, which provides constraints to characterize the mantle flow direction and strength of anisotropy. At most stations, the detected polarization directions of the fast wave are approximately parallel to the absolute plate motion (APM) direction of the North American plate, suggesting a coupling between the asthenosphere and the lithosphere. The similarity between the Appalachian Mountain’s strike and the fast directions, and the significant differences between APM direction and the fast directions at the eastern margin indicate a contribution of anisotropy from lithospheric deformational processes. The splitting time between the fast and slow shear waves, which can be utilized to characterize the strength of anisotropy, shows systematical distribution through the study area. The study confirm the contribution of both fossil fabrics in the lithosphere and present mantle flow in the asthenosphere to the pbserved seismic anisotropy.
