斷層核芯與破裂帶的變形對比(2/2)

Deformation of a fault (including fault core and damage zone) can result in either seismic slip (e.g., 1 m/s) or aseismic creeping (e.g., 100 nm/s). Conducting experiments with different slip rates on rocks is one of the methods to investigate fault deformation and the underlain mechanism. In the previous MOST project (Deciphering the seismically active faults from natural and experimental fault rocks), we successively developed a gouge sample holder that allows to deform fault gouges at both seismic rates and high normal stresses under water-saturated conditions. This experimental approach allows to investigate the frictional behavior of the principal slip zone of the Chelungpu fault and the associated mechanism during earthquake ruptures. Integrated the NSF project for Hiroki Sone (Bulk rheology of fault damage zone materials and its implication for interseismic fault mechanics; i.e., the study of damage rocks deformed at low velocities) with the current MOST project (Revealing the contrast in deformation styles between fault core and damage zone throughout the seismic cycle; i.e., the study of gouges deformed at high velocities), we are able to reconstruct the full spectrum of fault behavior of the Chelungpu fault during the seismic cycle. To be capable of investigating different deformation types of a fault in Taiwan, including seismic slip to aseismic creeping on materials spanning from fault core to damage zone, this proposal aims to develop the technique and facility that allows to deform rocks at low velocities (e.g., 100 nm/s). The integration of rock-deformation techniques will be applied to the materials retrieved from drilling projects (e.g., Chihshang fault drilling, and Milun fault Drilling and All-inclusive Sensing in 2021) for probing fault mechanisms spanning from earthquake rupture to aseismic creeping and expand our understanding of fault deformation together with significant applications to natural faults. This proposal not only unravel the mechanics of both fault-oriented (seismic hazards-related) and landslide-oriented (engineering-related) slip but also echoes the idea ”OBservatory for Terra-Aqua INteractions, termed OBTAIN” promoted by the department of natural sciences and sustainable development of MOST.