Thermal regime of the Tarim Basin, Northwest China: a review

Abstract

ABSTRACTThe Tarim Basin, which is the largest basin in Central Asia, experienced a complicated tectonic evolution along with the development of the South Tianshan, Kunlun Mountains, and the Tibetan Plateau during the Phanerozoic. This article provides a systematic overview of the thermal regime of the Tarim Basin based on new results and previous studies. The present-day average heat flow and geothermal gradient of the Tarim Basin are 42.5 ± 7.7 mW/m2 and 20.7 ± 2.9°C/km, respectively. The palaeo-geothermal gradient in the eastern and central parts of the Tarim Basin during the early Palaeozoic was 35–39°C/km, which is higher than the gradient of 28–34°C/km in the northwestern part of the Basin. The palaeo-geothermal gradient has decreased gradually since the late Palaeozoic. Except for the Southeast Uplift, the thickness of the thermal lithosphere in most of the Tarim Basin ranges from 164 km to 205 km, and the Moho temperature varies from 520°C to 614°C. The thermo-rheological structure of the lithosphere in the Tarim Basin can be approximated by a typical jelly sandwich model with the exception of the Southeast Uplift, which can be represented by a crème brûlée model. Generally, the long-term sedimentation and subduction of the adjacent mountains had an important effect on the spatial differentiation of the thermal regime in the Tarim Basin. This study provides a detailed description of the shallow and deep thermal states of the Tarim Basin, which are important for hydrocarbon exploration in the basin and structural research on Central Asia.