The Geometry and Growth of Normal Faults
The impact of multiple extension events, stress rotation and inherited fabrics on normal fault geometries and evolution in the Cenozoic rift basins of Thailand
-
Published:January 01, 2017
-
CiteCitation
C. K. Morley, 2017. "The impact of multiple extension events, stress rotation and inherited fabrics on normal fault geometries and evolution in the Cenozoic rift basins of Thailand", The Geometry and Growth of Normal Faults, C. Childs, R. E. Holdsworth, C. A.-L. Jackson, T. Manzocchi, J. J. Walsh, G. Yielding
Download citation file:
- Share
Abstract:
The rift basins of Thailand exhibit remarkable diversity of fault displacement patterns, fault length–displacement characteristics and mapped fault patterns during late rift, and post-rift, stages. These patterns reflect influences by: (1) zones of strength anisotropy in the pre-rift basement; (2) syn-rift fault patterns on post-rift faults; (3) spatial stress deflection, commonly related to irregularities in major fault profiles, and the basement–sediment interface; (4) temporal stress rotation, usually related to changes in the regional plate setting; and (5) varying strength properties (strain hardening or softening) of fault zones during their life. These influences created strongly segmented boundary faults, and long, low-displacement post-rift fault trends. The former are commonly strongly over-displaced, while the latter can be strongly under-displaced with respect to their length compared with typical length:displacement distributions. Seismic interpretation of multi-rift fault patterns requires 3D data to identify the complexities, otherwise the linkage pattern between deeper and shallower faults, and the changing fault strike-directions with depth, may be incorrectly mapped. Incorrect identification of fault patterns as breached relay structures may also arise. Oblique extension, the influence of pre-existing trends and stress rotation in multi-phase rifts provides a more comprehensive explanation for the observed features than the strike-slip interpretation of previous studies.
- anisotropy
- Asia
- basement
- basins
- boundary faults
- Cenozoic
- displacements
- extension faults
- extension tectonics
- fabric
- Far East
- faults
- geometry
- geophysical profiles
- Gulf of Thailand
- high-angle faults
- interfaces
- low-angle faults
- Malay Basin
- mechanical properties
- mechanics
- normal faults
- North Pacific
- Northwest Pacific
- orientation
- Pacific Ocean
- patterns
- regional
- rift zones
- rotation
- sedimentary cover
- segmentation
- seismic profiles
- South China Sea
- strength
- stress
- tectonics
- temporal distribution
- Thailand
- West Pacific
- Nakhon Basin
- Bongkot Thailand