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Highlights: [•] The seismicity rate in central Taiwan remained high after Chi-Chi. [•] The rate increase could be attributed to the Chi-Chi coseismic stress increase. [•] Postseismic stress evolution cannot explain seismicity behavior. [Copyright &y& Elsevier]

Highlights: [•] P- and S-velocity anomalies in the mantle beneath Taiwan are presented. [•] Seismic tomography clearly reveals two slabs beneath Taiwan. [•] The origin of Taiwan is due to collision of two oppositely oriented subduction zones. [ABSTRACT FROM AUTHOR]

Abstract: The first local magnitude scale (ML ) for Northern Vietnam has been derived using a portable broadband seismic network in Northern Vietnam as part of the cooperation between the Vietnam Institute of Geophysics and the Institute of Earth Sciences at Academia Sinica, Taiwan. The composite horizontal peak amplitude data used in this study is comprised a total of 202 amplitude records from 14 broadband stations, which measure 36 shallow earthquakes with focal depths less than 36km, occurred in and around north-western Vietnam during 01/2006–10/2007. The new distance-correction function obtained in this study is where A 0 and r are the empirically determined distance correction and hypocentral distance, respectively. This distance-correction relation for Northern Vietnam is quite similar to one for southern California, implying relative efficient attenuation with distances. The correlation between the new ML and duration magnitudes (Md ), which is still being used for making the official earthquake bulletin in Vietnam, is expressed as [ABSTRACT FROM AUTHOR]