Earth Observatory Blog

Submitted on 04 Mar 2019 by:

Scientists from Academia Sinica (Taiwan) and the Earth Observatory of Singapore (EOS) have published a study in Science Advances, using a technique developed at EOS for discerning the strength of rocks in Earth’s continental lower crust.

The strength of the lower crust plays an important role in controlling the size and time between earthquakes, as well as the evolution of plate tectonics and growth of mountains over geological time. Using our method we are able to image how the strength of the rocks vary in the lower crust beneath Taiwan, measured by their effective viscosity. If rocks have high effective viscosity, it means they are strong, and...

Submitted on 31 May 2016 by:

A magnitude-7.2 deep earthquake occurred offshore northeastern Taiwan on 31 May 2016. This is the second significant quake to have struck northern Taiwan this month, and it was powerful enough to generate strong ground motion throughout the whole of northern Taiwan.

Unlike the shallow Ilan earthquake that had occurred earlier this month on 12 May 2016, the Central Weather Bureau of Taiwan estimated the hypocentre of today’s M 7.2 earthquake to be located approximately 270 km below the seafloor. This suggests that this event is likely to have occurred at the northward subducting slab of the Philippine Sea Plate.

The collision and subduction of the Philippine Sea Plate with the Eurasian Plate are responsible for the creation of the island of Taiwan for the past...

Submitted on 16 May 2016 by:

A magnitude-5.6 earthquake occurred offshore Ilan in northeastern Taiwan on 12 May 2016. According to the United States Geological Survey, this is the second significant quake to have struck Taiwan this year.

Approximately an hour after the M 5.6 mainshock took place, a M 5.5 aftershock occurred east of the mainshock’s point of origin. This series of earthquakes is commonly referred to as a “doublet,” where two quakes of similar magnitudes occur in succession within a relatively short period of time.

The real-time fault-plane solutions1 show that both of these earthquakes were a result of normal faulting.2 Even though it was reported that tremors could be felt as far as northern Taiwan, including Taipei, the degree of ground motion in Taipei was moderate and therefore the...