拖缆前后源双向同时激发采集新技术探索

Testing of fore and after source double-way simultaneous shooting technology on offshore seismic acquisition

常规拖缆采集时其单边激发、单边接收的作业模式会导致采集方位角单一。在潜山或高陡倾角构造区采用此方式采集地震数据时,会造成一侧照明不足、成像模糊。在分析常规拖缆采集作业局限性的基础上,提出了拖缆前后源双向同时激发采集技术,该技术可有效提升高陡倾角构造两侧的照明度。对比不同的实现方式,优选辅助震源船追随尾标航行激发的作业模式,首次在国内实现了拖缆前后源双向同时激发采集。渤海油田JZ区块实际应用结果表明,与常规拖缆采集相比,该方法有效提高了潜山面的成像效果,提升了高陡倾角构造区拖缆作业潜力;其技术流程可行,作业模式合理,对挖掘拖缆作业潜力有一定的借鉴意义。

Conventional towed cable seismic acquisition operational mode causes unilateral sufficient illumination and blur image at buried hill or high-steep structure area due to its single-side shooting and single-side receiving with single azimuth.We put forward acquisition design of fore and after source double-way simultaneous shooting through analyzing limitation of conventional towed cable to improve illumination of both sides for the high-steep structure. In China, fore and after source double-way simultaneous shooting operation is firstly carried out with optimal selection the operation mode, in which the assistant seismic vessel is shooting by chasing the tail-buoy by comparing the different implementations.The application in JZ block proves that：compared to conventional towed cable seismic acquisition, the new method can improve the imaging of buried hill and fully promote the operational potentiality in buried hill and high-steep structure area.The technical process is feasible and the operation mode is reasonable, which is of significant reference for potentiality exploitation of towed cable seismic operation.