论文部分内容阅读
通过 1996年 9月在莺歌海盆地两条垂直盆地走向的海底地震折射与广角反射测线 ,96 2和 96 3的震相识别 ,以及数据的初步处理与分析 ,揭示了在盆地 1号断裂以西 ,3 5～ 9 0km深处存在一低速层 .此低速层速度值为 3 0～ 3 5km/s,其顶界面深度从NE的 3 5km向SW端增深至 4 6km .低速层以上地层的折射速度变化为 2 0～ 4 1km/s.在 1号断裂以东的基底高处 ,折射地震波速较高 ,为 5 8～ 6 2km/s .在西沙海槽做了一条NNW～SSE向测线 ,观测到Moho界面等深部地震信息 .上述莺歌海盆地低速层的顶界大致与测井资料显示的含气主异常高压段的顶界相当 ,显示地层欠压实并表明盆地在此层段含有较多天然气
Seabed seismic refraction and wide-angle reflection survey, phase identification of 96 2 and 96 3, and preliminary data processing and analysis of the seabed seismic strike in September 1996 in two vertical basins in the Yinggehai Basin reveal that in the basin No. 1 fault To the west, there is a low-velocity layer in the depth of 35 km to 90 km.The velocity of this low-velocity layer ranges from 30 km3 to 35 km / s, and the depth of its top interface deepens from 35 km to 45 km to the SW side. The refraction velocity varies from 20 km / s to 41 km / s.With the basement east of the fault number 1, the refraction seismic velocity is high, ranging from 58 km / s to 62 km / s, and an NNW ~ SSE strike is made in the Xisha trough Line and observed deep seismic information such as Moho interface.The top of the low-velocity layer in Yinggehai Basin is roughly equivalent to the top of the main gas-rich anomalous high-pressure section recorded by well logging data, indicating that the formation is not compacted and indicates that the basin is here The intervals contain more natural gas