On the basis of processing gravity and magnetic data in Qiongdongnan basin, the gravity and magnetic characteristics were obtained. Inverted calculation was conducted on the gravity and magnetic basement depth by using Three-dimensional Parker Process. The result shows that the gravity basement depth varies from 1km to 11km while the magnetic basement depth from 5km to 11km. The difference between gravity and magnetic basement depth may result from Mesozoic sedimentary found in the seismic profiles. Furthermore, by contrast with the seismic profiles and well data, the basement characteristics of Qiongdongnan basin were analyzed. The evolutionary history of the basement concluded as follows: Both the South China Block and mdo-China Block belong to the Gondwana super continent from their crystal basement comparison. The South China Block drift from the Gondwana continent from Carboniferous and ocean between the south china block and Indo-china block called the northern branch of Paleo-Tethys. After late Triassic, the two blocks collided and the Paleo-Tethys disappeared and gave rise to the uplift of the NW South China Sea. So that the Mesozoic marine sediments absent in this area.
Qiongdongnan basin,three-dimensional Parker Process,Gravity and magnetic data model , basementtectonic evolution
NETL
NSTL
维普
万方数据
