HEAT FLOW IN CENOZOIC RIFTS IN EAST CHINA
S.V. Lysak, and R.P. Dorofeeva
Institute of the Earth's Crust, Siberian Branch of the RAS, 128 ul. Lermontova, Irkutsk, 664033, Russia
Keywords: Rifting, heat flow, deep structure, geodynamics, geothermal activity
Pages: 655-667
Abstract
Heat flows in continental East China, which includes four Cenozoic rifts that belong to the western or eastern rift systems, vary from 26 to 106 mW/m2, with the mean of 61 ± 2 mW/m2. The rifts are generally hotter than their surroundings (the mean of 68-70 mW/m2 against 49-56 mW/m2). Especially high deep flow over 80-100 mW/m2 is associated with rift basins and active faults. The intensity of rifting and recent geothermal activity in the region correlate with heat flow variations and are consistent with the evolution and deep structure of main tectonic units. Cenozoic rifting in the eastern system and its abnormal heat flows are induced by heating from a rising mantle plume related to the subduction of the Pacific plate beneath eastern Eurasia. Rifting in the western system has been controlled mostly by horizontal strain and rotation of the Ordos block under the joint effect of India and Eurasia, with minor thermal control.
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