Pore pressure in fault zones

王其允 教授

加州大学伯克利分校

2024.10.18（星期五）15:00，理科二号楼2821

摘要：

     The Earth’s crust is crisscrossed by numerous faults, hence an understanding of pore pressure in faults is of primary importance for understanding fault behavior and crustal dynamics. On the other hand, pore pressure in faults has been a matter of ongoing debate for nearly half a century. In this talk I will first briefly review the evidence for a weak San Andreas fault in California and the attempts around the world to directly measure fault properties by deep drilling into ruptured fault zones, and I will focus on the attempt to measure pore pressure in the San Andreas fault core during the SAFOD project. In particular, I will discuss why this attempt was not successful. Given the difficulty for direct measurement of pore pressure in natural fault cores, I will review a recent study (Chu and Wang, 2023) that provided a first-order understanding of the evolution of pore pressure in a laboratory fault core during frictional sliding. Our result shows that large variations in pore pressure may occur during fault motion and that such pore pressure events may last for a long period of time. Together with the measured permeability of the fault core, our new constitutive relation may provide a basis for simulating such pore pressure events in natural faults and hence the dynamics of natural faults. Finally, our result may provide an explanation of the anastomosis in natural fault zones.

报告人简介：

  王其允（Chi-Yuen Wang）是美国加州大学伯克利分校的终身教授，是国际知名的地质和地球物理学家。1958年毕业于国立台湾大学，1960年赴美、1964年获得哈佛大学博士学位，1967年任职加州大学伯克利分校。长期致力于研究岩石力学和地震与水的相互影响，涉及到地质学、地球物理学、地震学、水文学等多个学科，并在这些研究领域做出了杰出贡献。王其允教授在Nature、Nature Communications、Communications Earth & Environment、Geology、GRL、JGR等国际知名期刊发表SCI检索论文100多篇，其中在Nature发表论文8篇。并著有专著《Earthquakes and Water, 2010》及《Water and Earthquake, 2021》。