Three-dimensional thermal structure of the Chinese continental crust and upper mantle |
| |
摘 要: | We invert S-wave velocities for the 3D upper-mantle temperatures, in which the position with a temperature crossing the 1300℃ adiabat is corresponding to the top of the seismic low velocity zone. The temperatures down to the depth of 80 km are then calculated by solving steady-state thermal conduction equation with the constraints of the inverted upper-mantle temperatures and the surface temperatures, and then surface heat flows are calculated from the crustal temperatures. The misfit between the calculated and observed surface heat flow is smaller than 20% for most regions. The result shows that, at a depth of 25 km, the crustal temperature of eastern China (500―600℃) is higher than that of western China (<500℃). At a depth of 100 km, temperatures beneath eastern and southeastern China are higher than the adiabatic temperature of 1300℃, while that beneath west China is lower. The Tarim craton and the Sichuan basin show generally low temperature. At a depth of 150 km, temperatures beneath south China, eastern Yangtze craton, North China craton and around the Qiangtang terrane are higher than the adiabatic temperature of 1300℃, but is the lowest beneath the Sichuan basin and the regions near the Indian-Eurasian collision zone. At a depth of 200 km, very low temperature occurs beneath the Qinghai-Tibet Plateau and the south to the Tarim craton.
|
收稿时间: | 6 November 2006 |
修稿时间: | 19 March 2007 |
Three-dimensional thermal structure of the Chinese continental crust and upper mantle |
| |
Authors: | An MeiJian Shi YaoLin |
| |
Institution: | 1. Laboratory of Computational Geodynamics, Graduate University of Chinese Academy of Sciences, Beijing 100049, China;Key Laboratory of Crust Deformation and Processes and Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China 2. Laboratory of Computational Geodynamics, Graduate University of Chinese Academy of Sciences, Beijing 100049, China |
| |
Abstract: | We invert S-wave velocities for the 3D upper-mantle temperatures, in which the position with a temperature crossing the 1300°C
adiabat is corresponding to the top of the seismic low velocity zone. The temperatures down to the depth of 80 km are then
calculated by solving steady-state thermal conduction equation with the constraints of the inverted upper-mantle temperatures
and the surface temperatures, and then surface heat flows are calculated from the crustal temperatures. The misfit between
the calculated and observed surface heat flow is smaller than 20% for most regions. The result shows that, at a depth of 25
km, the crustal temperature of eastern China (500–600°C) is higher than that of western China (<500°C). At a depth of 100
km, temperatures beneath eastern and southeastern China are higher than the adiabatic temperature of 1300°C, while that beneath
west China is lower. The Tarim craton and the Sichuan basin show generally low temperature. At a depth of 150 km, temperatures
beneath south China, eastern Yangtze craton, North China craton and around the Qiangtang terrane are higher than the adiabatic
temperature of 1300°C, but is the lowest beneath the Sichuan basin and the regions near the Indian-Eurasian collision zone.
At a depth of 200 km, very low temperature occurs beneath the Qinghai-Tibet Plateau and the south to the Tarim craton.
Supported by China Postdoctoral Science Foundation, Key Program of NSFC (National Science Foundation of China) (Grant No.
40234042), and NSFC (Grant Nos. 40674058 and 40374038) |
| |
Keywords: | crust upper mantle temperature seismic velocity China |
本文献已被 万方数据 SpringerLink 等数据库收录! |
|