Cenozoic structural evolution of the Andaman Sea: evolution from an extensional to a sheared margin
Published:January 01, 2016
C. K. Morley, 2016. "Cenozoic structural evolution of the Andaman Sea: evolution from an extensional to a sheared margin", Transform Margins: Development, Controls and Petroleum Systems, M. Nemčok, S. Rybár, S. T. Sinha, S. A. Hermeston, L. Ledvényiová
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The Andaman Sea is proposed to have developed from a margin where Palaeogene back-arc collapse closed a mid-Cretaceous back-arc oceanic basin, and resulted in the collision between island arc crust to the west and the western margin of Sundaland. Subsequent east–west to WNW–ESE extension during the Late Eocene–Oligocene resulted in highly extended continental crust underlying the Alcock and Sewell rises, and the East Andaman Basin, and moderately extended crust in the Megui–North Sumatra Basin. As India coupled with western Myanmar, the margin became dominated by dextral strike-slip and NNW–SSE transtensional deformation during the Miocene. The narrow belt of NNW–SSE-directed extension is proposed to have focused on the region where ductile middle crust remained following Late Eocene–Oligocene extension, whereas strike-slip faults are located in the regions of necking where ductile middle crust was considerably thinned by Late Eocene–Oligocene extension. The last phase of NNW–SSE-extension switched between probable Late Miocene–Early Pliocene seafloor spreading, and extension (by dyke intrusion and faulting) in the Alcock and Sewell rises, and then recently back to the spreading centre.
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Transform Margins: Development, Controls and Petroleum Systems
This volume covers the linkage between new transform margin research and increasing transform margin exploration. It offers a critical set of predictive tools via an understanding of the mechanisms involved in the development of play concept elements at transform margins. It ties petroleum systems knowledge to the input coming from research focused on dynamic development, kinematic development, structural architecture and thermal regimes, together with their controlling factors. The volume does this by drawing from geophysical data (bathymetry, seismic, gravity and magnetic studies), structural geology, sedimentology, geochemistry, plate reconstruction and thermo-mechanical numerical modelling. It combines case studies (covering the Andaman Sea, Arctic, Coromandal, Guyana, Romanche, St. Paul and Suriname transform margins, the French Guyana hyper-oblique margin, the transtensional margin between the Caribbean and North American plates, and the Davie transform margin and its neighbour transform margins) with theoretical studies.