Thermal and Tectonic Structures of the Crust and Upper Mantle in Eastern China

Abstract

Almost all hydrothermal areas of eastern China distribute in the epicontinental region to the east of the Daxinganling-Taihangshan-Wulingshan gravity gradient zone, and the temperature of hot springs is intermediate or low. The underground temperature gradient in the sedimentary blanket is decreasing with the increase of the basement depth. The temperature profile corresponds to the relief of basement, that is, the higher geothermal anomalies appear in the uplifted region of the upper mantle, and the strike of the deep underground temperature anomaly corresponds to that of the tectonic structure. As a whole, the underground temperature field in eastern China has an increasing trend from the north to the south and from the west to the east. This trend corresponds to the decrease of the crustal thickness. The relation between the heat flow profile and the tectonic structures of the crust and upper mantle is very close. These characteristics conclude that the thermal structure in the epicontinental region of eastern China is connected directly with the motions of the Pacific and Eurasian Plates.