AAPG Bulletin, V. 82 (1998), No. 1 (January 1998), P. 147-159.

Structural Features of Northern Tarim Basin: Implications for Regional Tectonics and Petroleum Traps¹

Dong Jia, Huafu Lu, Dongsheng Cai, Shimin Wu, Yangshen Shi, and Chuming Chen²

©Copyright 1998.  The American Association of Petroleum Geologists.  All Rights Reserved

¹Manuscript received September 29, 1995; revised manuscript received December 16, 1996; final acceptance July 23, 1997.
²Department of Earth Sciences, The Oil-Gas Research Centre, Nanjing University, Nanjing, 210093, People’s Republic of China.

This study is a part of a research project on the Tarim basin supported by the State Scientific Committee of China. We especially thank the Tarim Petroleum Exploration & Development Bureau of the CNPC for generously providing some of the background information, and Chengzao Jia for his valuable suggestions. We also thank Edmund Z. Chang and Mian Liu for critically reviewing the manuscript. 

ABSTRACT

The rhombus-shaped Tarim basin in northwestern China is controlled mainly by two left-lateral strike-slip systems: the northeast-trending Altun fault zone along its southeastern side and the northeast- trending Aheqi fault zone along its northwestern side. In this paper, we discuss the northern Tarim basin’s structural features, which include three main tectonic units: the Kalpin uplift, the Kuqa depression, and the North Tarim uplift along the northern margin of the Tarim basin. Structural mapping in the Kalpin uplift shows that a series of imbricated thrust sheets have been overprinted by strike-slip faulting. The amount of strike-slip displacement is estimated to be 148 km by restoration of strike-slip structures in the uplift. The Kuqa depression is a Mesozoic- Cenozoic foredeep depression with well-developed flat-ramp structures and fault-related folds. The Baicheng basin, a Quaternary pull-apart basin, developed at the center of the Kuqa depression. Subsurface structures in the North Tarim uplift can be divided into the Mesozoic-Cenozoic and the Paleozoic lithotectonic sequences in seismic profiles. The Paleozoic litho-tectonic sequence exhibits the interference of earlier left-lateral and later right-lateral strike-slip structures. Many normal faults in the Mesozoic-Cenozoic litho-tectonic sequence form the negative flower structures in the North Tarim uplift; these structures commonly directly overlie the positive flower structures in the Paleozoic litho-tectonic sequence. The interference regions of the northwest-trending and northeast-trending folds in the Paleozoic tectonic sequence have been identified to have the best trap structures. Our structural analysis indicates that the Tarim basin is a transpressional foreland basin rejuvenated during the Cenozoic.