南海北部深水地震勘探所遇到的挑战与对策

Challenges and Measures in Seismic Exploration in Northern Deepwater Area of South China Sea

总结了近年来南海北部深水区地震勘探中遇到的挑战,包括海水深度大、海底崎岖、硬质海底产生的强烈多次波和地下地质构造复杂等。从采集和处理入手,分析研究了其影响地震资料品质的根本原因,提出了解决这些问题的对策,采集方面包括选择更有利的采集方向、优化震源设计、改变拖缆方式、缩小炮间距和增加电缆长度等;处理方面包括三维SRME技术、各向异性速度分析及高阶动校正技术、倾角共反射面叠加技术、叠前深度偏移技术等。此研究为今后深水地震采集和处理提供了参考与借鉴。

The challenges in seismic exploration in northern deepwater area of South China Sea are summarized in this paper, includ- ing deeper water depth, rugged seafloor, strong multiples generated by hard sea：floor, complicated geological structures and so on. The main reasons influencing the quality of seismic data have been analyzed through analyzing seismic data acquisition and processing process. The measures to solve these problems have been proposed. In seismic data acquisition, more favorable acquisition direction, optimization source design, changing the streamer mode, shorter shot space, longer streamer should be taken into consideration. The seismic data processing, advanced processing techniques such as 3D SRME, anisotropic velocity analysis, high order NMO correc- tion, dip angle CRS, PSDM should be used. This study provides a reference and experience for future deepwater seismic data acqui- sition and processing.