【摘要】 本文通过处理琼东南盆地现有的重磁数据资料,得到琼东南盆地重磁特征,并采用三维Parker法进行重磁基底深度的反演,获得琼东南盆地的重力基底深度变化在1～11km之间,磁力基底深度变化在5～11km之间,结合地震剖面的重磁震联合反演结果和钻井资料推断琼东南盆地的基底岩性主要以酸性花岗岩和中性安山岩为主,少量陆相中生界地层.琼东南盆地的基底演化表现为早期主要与古特提斯洋的演化相关,晚期则与太平洋板块的俯冲密切相关.更多还原

【Abstract】 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 Indo-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.更多还原