Tectonic Evolution of the Pamir Recorded in the Western Tarim Basin (China):Sedimentologic and Magnetostratigraphic Analyses of the Aertashi Section

Blayney, T. and Dupont-Nivet, G. and Najman, Y. and Proust, J.-N. and Meijer, N. and Roperch, P. and Sobel, E.R. and Millar, I. and Guo, Z. (2019) Tectonic Evolution of the Pamir Recorded in the Western Tarim Basin (China):Sedimentologic and Magnetostratigraphic Analyses of the Aertashi Section. Tectonics, 38 (2). pp. 492-515. ISSN 0278-7407

Full text not available from this repository.

Abstract

The northward indentation of the Pamir salient into the Tarim basin at the western syntaxis of the India-Asia collision zone is the focus of controversial models linking lithospheric to surface and atmospheric processes. Here we report on tectonic events recorded in the most complete and best-dated sedimentary sequences from the western Tarim basin flanking the eastern Pamir (the Aertashi section), based on sedimentologic, provenance, and magnetostratigraphic analyses. Increased tectonic subsidence and a shift from marine to continental fluvio-deltaic deposition at 41 Ma indicate that far-field deformation from the south started to affect the Tarim region. A sediment accumulation hiatus from 24.3 to 21.6 Ma followed by deposition of proximal conglomerates is linked to fault propagation into the Tarim basin. From 21.6 to 15.0 Ma, increasing accumulation rates of fining upward clastics is interpreted as the expression of a major dextral transtensional system linking the Kunlun to the Tian Shan ahead of the northward Pamir indentation. At 15.0 Ma, the appearance of North Pamir-sourced conglomerates followed at 11 Ma by Central Pamir-sourced volcanics coincides with a shift to E-W compression, clockwise vertical-axis rotations and the onset of growth strata associated with the activation of the local east vergent Qimugen thrust wedge. Together, this enables us to interpret that Pamir indentation into Tarim had started by 24.3 Ma, reached the study location by 15.0 Ma and had passed it by 11 Ma, providing kinematic constraints on proposed tectonic models involving intracontinental subduction and delamination.

Item Type:
Journal Article
Journal or Publication Title:
Tectonics
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/1900/1908
Subjects:
ID Code:
131558
Deposited By:
Deposited On:
05 Mar 2019 16:00
Refereed?:
Yes
Published?:
Published
Last Modified:
26 May 2020 07:39