%A Kalpna Gahalaut
%A Thai Anh Tuan
%A N. Purnachandra Rao
%J Bulletin of the Seismological Society of America
%T Rapid and Delayed Earthquake Triggering by the Song Tranh 2 Reservoir, Vietnam
%X Impoundment of the Song Tranh 2 reservoir in Vietnam was started in late
2010, and earthquakes started occurring in its vicinity soon after that. Frequency of
earthquakes increased after the reservoir water level was brought down in June 2012.
We computed the influence of the reservoir water load and pore pressure and used the
concept of fault stability. The reservoir water load alone destabilized existing predominantly
dextral strike-slip faults of the region and hence led to triggering of earthquakes
soon after its impoundment. Pore pressure further destabilized these faults and brought
additional faults under destabilization. Time delay between the maximum reservoir
water level and pore pressure buildup due to diffusion leads us to conclude that the
increase in seismicity at low water stands in the reservoir is primarily due to the increase
in pore pressure during that period. We propose that this is an unambiguous case of rapid
and delayed earthquake triggering by a reservoir impoundment.
%N 5
%V 106
%D 2016
%R doi:10.1785/0120160106
%I Seismological Society of America
%L epos1773