宽线加大基距组合技术在喀什北区块复杂山地的应用

Application of broadened line plus long distance geophone array seismic technique in the complex mountainous area of north Kashgar

喀什北区块位于新疆塔里木盆地西端,地表起伏剧烈,地腹构造高陡、断裂发育。地震勘探难点主要表现在表层结构复杂、次生干扰严重、激发接收条件差、资料信噪比低、成像困难等。针对这些问题,在喀什北区块采用了"宽线加大基距组合"的新采集方式。宽线加大基距组合技术采集得到的地震资料与常规地震资料的对比结果表明,新的采集方式有效地提高了覆盖次数,压制了干扰波,剖面品质有了大幅度提高。这为构造解释提供了有利条件,为发现、落实构造主体和部署未来的钻探目标创造了有利条件。

North Kashgar area is located in the west of Tarim basin which is characterized by fluctuating surface,high-steep subsurface structures and developed faults.The difficulties in exploration include complex surface structure,serous secondary interference,poor shooting and receiving conditions,low signal-to-noise of the seismic data,which leads to bad imaging results.Aiming at the problems, we adopted broadened line plus long distance geophone array seismic technique to acquire seismic data in the area.The obtained seismic data was compared to conventional data.The result indicates that the new acquisition method effectively improved the fold, pressed the interference,and the quality of the seismic sections was largely increased,which provides beneficial conditions for the discovery and identification of main structures,as well as the deployment of drilling location.