- Dit event is voorbij.
Lezing Eldert Advokaat
28 november 2018 @ 17:00 - 18:30
“SE Asia is located in the zone of convergence between the major plates of Eurasia, India, Australia, and the Pacific. SE Asia comprises a heterogeneous assemblage of fragments derived from Cathaysia (Eurasia) in the north and Gondwana in the south, separated by suture zones representing closed former ocean basins. The western part of the region comprises Sundaland, which was formed by Late Permian-Triassic amalgamation of continental and arc fragments now found in Indochina, the Thai-Malay Peninsula, and Sumatra. On Borneo, the western part of Kuching Zone formed the eastern margin of Sundaland since the Triassic. Gondwana-derived terranes accreted to the southern margin of the western Kuching Zone in the Cretaceous, whereas South China-derived fragments accreted to the northern margin of the Kuching Zone in the Miocene. SE Asia now hosts the strongly curved Sunda and Banda subduction zone. Based on paleomagnetic data and seismic tomographic evidence, recent studies argue that these Cenozoic subduction zones were straight when they were formed, and became curved through opposite rotation on the northwestern and southeastern ends of this system. SE Asia may thus represent a closing orocline. In this talk I show how I developed a plate kinematic model for SE Asia, and how I restored oroclinal bending of the Sunda and Banda subduction systems. Based on this reconstruction, I will show how relative rotations between Indochina, Sundaland and Borneo were accommodated by extension, strike slip faulting and basin inversion in the Thai-Malay Peninsula and Sunda Shelf. Finally, I will show how oroclinal bending may have been driven by India-Asia collision-related extrusion processes in the northwest and the advancing collision of Australia with SE Asia in the southeast.”