Experimental investigations on the deformation behavior of sediment in the shallow region of the Nankai, North Sumatra, and Aleutian subduction zones

这项工作的主要目的是描述俯冲带沉积物的物理性质。来自南开海槽、苏门答腊和阿留申海沟的沉积物实验将在德克萨斯农工大学的岩石力学实验室进行。实验将在高压和高温的条件下进行，以模拟沉积物被带到地球深处，当一个构造板块俯冲到另一个板块下面时所遇到的条件。该项目的结果将有助于了解断层滑动和世界范围内俯冲带产生海啸的可能性。本项目将支持一名早期职业女性研究人员作为georisms博士后研究员。本研究旨在了解俯冲带浅层部分的变形行为，在那里，大逆冲地震破裂会产生更大的位移和地面变形。该项目将解决一些关键的基本问题，即俯冲带的浅层近海沟部分是否被锁定并积累应变或完全爬行。将对来自三个不同俯冲系统（南开海槽、苏门答腊和阿留申俯冲带）的沉积物样本在高压、高温和一系列应变速率下进行固结和蠕变实验。该项目的研究目标是1)表征弹性、塑性和粘性变形行为作为压力、温度、应变速率和沉积物岩性的函数；2)评估俯冲带浅层近海沟区域应变积累和同震滑动破裂传播的潜力。该项目将促进对俯冲带应变积累、断层耦合和滑动行为的认识。

The main objective of the work is to characterize the physical properties of sediments at subduction zones. Experiments on sediments from the Nankai Trough and the Sumatra and Aleutians Trench will be conducted at the rock mechanics laboratory at Texas A&M University. The experiments will be run at high pressure and temperature conditions to simulate the conditions that the sediments encounter as they are carried deep into the earth as one tectonic plate plunges beneath another. The project results will aid in understanding slip on faults and the potential for tsunami generation at subduction zones worldwide. This project will support an early-career female researcher as a GeoPRISMS post-doctoral fellow.This research aims to understand deformation behavior in the shallow portion of subduction zones where greater displacement and ground deformation can occur in response to megathrust earthquake ruptures. This project will address key fundamental questions about whether the shallow near-trench portion of a subduction zone is locked and accumulating strain or fully creeping. Consolidation and creep experiments will be conducted at elevated pressures and temperatures and at a range of strain rates on sediment samples from three different subduction systems - Nankai Trough, Sumatra, and Aleutian subduction zones. The research goals of the project are to 1) characterize the elastic, plastic, and viscous deformation behaviors as a function of pressure, temperature, strain rate, and sediment lithology and 2) assess the potential for strain accumulation and co-seismic slip rupture propagation in the shallow near-trench regions of subduction zones. The project will advance knowledge of strain accumulation, fault coupling, and slip behavior at subduction zones.