16th GRC International Frontier Seminar

Strain partitioning and fault evolution in plate boundary zones: Insights from numerical modeling


Prof. Mian Liu
Dept. of Geological Sciences, University of Missouri, USA


26 September 2006　17:0-18:00
Room 301, Kogi-to Bldg, Faculty of Science, Ehime University

　Plate boundaries are often zones of diffuse deformation. I present here results of numerical investigation of strain partitioning and fault evolution in two plate boundaries: the San Andreas Fault (SAF) plate boundary zone and the Sunda-Banda Archipelago. The SAF system is the transform plate boundary between the Pacific and the North American plates, yet relative plate motion is broadly distributed. To explore the control on fault slip distribution both along the main trace of the SAF and among the secondary faults, we have developed a regional-scale 3D visco-elasto-plastic finite element model. The results indicate a strong geometrical influence of the SAF on the along-strike variations of stress and deformation. The Sunda-Banda Archipelago provides a different example of plate boundary zone evolution. Both GPS data and coral-tereace dating show shifting of strain localization from near the plate interface to the back arc thrusts in the East Timor region. Our modeling results showed that the initiation of the continent-arc collision in the Timor region may explain the cessation of oceanic floor spreading in the south Banda basin and development of the back-arc thrust systems, which now accommodates ~60% of plate convergence and may eventually become the new plate boundary. 　


　　



　　　　　　　お問い合わせ先： irifune@dpc.ehime-u.ac.jp TEL 089-927-9645
　　　　　　　詳細情報：http://www.ehime-u.ac.jp/~grc/

主催：愛媛大学地球深部ダイナミクス研究センター