The role of the west-dipping collision boundary fault in the Taiwan 2022 Chihshang earthquake sequence.

On 17-18 September 2022, an earthquake sequence with a moment magnitude of 6.6 foreshock and a 7.0 mainshock occurred in southeast Taiwan along the Longitudinal Valley.

Seismic Detection of a Magma Reservoir beneath Turtle Island of Taiwan by S-Wave Shadows and Reflections.

Although surface geology, eruption information and clustering seismicity all suggest Turtle Island (Kueishantao) of northern Taiwan is an active volcano, there was no direct evidence to conclude that magma reservoirs exist beneath it. Even less evidence is available to determine their spatial configuration. If the magma reservoirs are filled by liquids and melt, S-waves are totally reflected and leave behind a shadow, like when passing through the Earth's outer core.

Isotropic events observed with a borehole array in the Chelungpu fault zone, Taiwan.

Shear failure is the dominant mode of earthquake-causing rock failure along faults. High fluid pressure can also potentially induce rock failure by opening cavities and cracks, but an active example of this process has not been directly observed in a fault zone. Using borehole array data collected along the low-stress Chelungpu fault zone, Taiwan, we observed several small seismic events (I-type events) in a fluid-rich permeable zone directly below the impermeable slip zone of the 1999 moment magnitude 7.