Posted on 12/12/2011
Two regionally significant faults in Thailand are reported by Ian Watkinson, Chris Elders, Robert Hall and Australian collaborators, Geoff Batt, Fred Jourdan and Neal McNaughton (UWA & Curtin Univ) in the Journal of Geophysical Research . Although these faults have important influences on geomorphology, hydrocarbons, earthquakes and tsunamis, this is the first time high precision dating methods have been used to explore their temporal & spatial evolution. The data challenge the long-held belief that all major faults in SE Asia were formed when the Indian plate collided with Asia building the Himalayan mountains. In addition they demonstrate that not all "young" deformation in Thailand is the result of lateral movement of crustal blocks away from the Himalayan collision. For the first time they show how partial melting and magma emplacement occurred both before and during deformation, and how such magmatism can be used to date ancient fault activity.