analyzing the state of lithospheric stress in greater thailand through finite element modeling

Open Access
Author:
Meyers, Beth Sarah
Graduate Program:
Geosciences
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
July 11, 2014
Committee Members:
  • Kevin Patrick Furlong, Thesis Advisor
Keywords:
  • thailand
  • active faults
  • earthquakes
  • modeling
  • finite element
  • tectonics
  • geodynamics
  • shear stress
  • stress
Abstract:
Thailand and its surrounding regions occupy an important, but often overlooked, setting in terms of plate tectonics and lithospheric deformation. The lateral extrusion of Tibet southeastward and eastward along deep strike slip faults to the north and the Sumatra-Andaman subduction zone to the south and west bound the region of greater Thailand. While it is adjacent to some of the most seismically active plate boundaries and intraplate regions on Earth, this region has experienced only a low level of background seismicity. Thus, the long-term seismic potential of greater Thailand remains highly uncertain. Although historic seismicity is one indicator for future seismicity it is not the only tool we have for estimating seismic hazard; we can additionally assess the state of lithospheric stress. In an intraplate region the stress conditions will be largely controlled by the forces acting on its boundaries. We can analyze the intraplate stress conditions by utilizing fault structure, earthquake activity, and kinematics in the boundary area in concert with a numerical finite element model of lithospheric deformation in the region. In this way, we are able to estimate the overall stress conditions. Combined with known fault geometries, the shear stress output from the model can be used as a tool to assess the potential for earthquake activity in Thailand.