Structural evolution of the Northwest Tarim Basin, China
The sedimentary and structural record of the NW Tarim Basin, China, provides aninsight into the amalgamation of Central Asia and is an ideal area in which to examinethe impact of an inherited tectonostratigraphic framework on the evolution offoreland fold-thrust belts. The NW Tarim Basin contains a thick (3-16 km)sedimentary succession which was deposited from the Late Neoproterozoic onwards, and has been exhumed by a foreland fold-thrust belt system associated with the SouthTien Shan mountains during the Middle to Late Cenozoic. The research presented inthis thesis combines satellite image interpretation and field investigations in order toexamine the tectonostratigraphic framework of the NW Tarim Basin and to ascertainthe causes of lateral structural variability and partitioning of the foreland fold-thrustbelt system. The Upper Neoproterozoic to Lower Permian sedimentary succession records theprogressive evolution of the NW Tarim Basin as a rift, intracratonic and forelandbasin. Following a period of subaerial exposure throughout the Mesozoic, tectonicsubsidence from the Middle Cenozoic onwards was driven by flexural deflectionbeneath the Pamirs and Tien Shan orogenic belts. This was coupled with thedevelopment of a foreland fold-thrust belt system along the northwest margin of theTarim Basin. Lateral variations in the structural geometry, architecture and style of theforeland fold-thrust belt system correspond to changes in the thickness of thesedimentary succession and interaction with inherited, basement fault zones. An eastwesttransition from the wide, arcuate Keping Shan Thrust Belt into the narrowKashgar Fold Belt is ascribed to thickening of the Cenozoic (syn-tectonic) forelandbasin succession. In contrast, internal variations in the structural architecture of theKeping Shan Thrust Belt are governed by lateral changes in the thickness of thePalaeozoic (pre-tectonic) sedimentary succession. These changes occur abruptly acrossinherited, Early Permian fault zones that have been reactivated as strike-slip faults inorder to accommodate these lateral variations in the structure of the fold-thrust belt
Thesis, Dissertation, English, 2010
Imperial College London, 2010