Collaborative Research: Constraints on sediment physical properties at the Cape Fear and Currituck landslides from velocity analysis of new, open access seismic reflection data

GSTDTAP

项目编号	1830726
	Collaborative Research: Constraints on sediment physical properties at the Cape Fear and Currituck landslides from velocity analysis of new, open access seismic reflection data
	Derek Sawyer
主持机构	Ohio State University
项目开始年	2018
	2018-09-01
项目结束日期	2020-08-31
资助机构	US-NSF
项目类别	Standard Grant
项目经费	130498(USD)
国家	美国
语种	英语
英文摘要	Seafloor landslides that occur just offshore of continents can have significant impacts on coastal areas. On the continental margin offshore of the heavily populated U.S. Mid-Atlantic, about 15% of the continental slope shows scars from large submarine landslides. This study aims to understand the driving mechanisms behind these common features. The role that fluids within the sediments play in triggering landslides will be examined by applying new analysis techniques to existing data. Slope failure can occur gradually or catastrophically, and the type of failure will control the severity of the impacts to coastal areas. Results of this study will provide a better understanding of the following: (1) the natural hazard risk from tsunamis generated by catastrophic slope failures, (2) potential impacts when trapped greenhouse gases are released from both gradual and catastrophic failures, and (3) sedimentary systems along continental margins in a broader scientific sense. The project supports the training of two graduate students and a post-doctoral investigator. The Cape Fear and Currituck submarine landslides offshore North Carolina will be examined using open-access seismic reflection data. A key question for these and other slope failures is "What is the role of elevated pore-fluid pressure in promoting slope instability?" Using pre-stack waveform inversion (PWI) and high-quality seismic data, detailed information on variations in P- and S- wave velocity of sediments inside and outside of these two slide complexes will be obtained. The new velocity information will be integrated with other available information on sediment properties from coring and drilling to constrain variations in sediment physical properties between failed and un-failed regions. Variations in pore-fluid pressure will be estimated using an effective-medium approach relating velocity and effective stress. Also, the seismic profiles will be reprocessed through pre-stack depth migration using velocities obtained by PWI to improve imaging of slide features. This study will add critical new constraints on in situ sediment properties and the stress state within and around the Cape Fear and Currituck slide complexes to the growing body of information on these slides. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/73202
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Derek Sawyer.Collaborative Research: Constraints on sediment physical properties at the Cape Fear and Currituck landslides from velocity analysis of new, open access seismic reflection data.2018.