库车坳陷复杂山地宽线采集技术及应用效果

库车坳陷山地地震勘探受复杂地表和地下条件影响,激发和接收条件差,原始资料信噪比低,构造成像困难,影响地下构造形态认识和油气资源评价.在西秋里塔格构造带进行了宽线采集技术攻关,针对工区复杂的地震地质条件,提出了相应的技术对策.首先对宽线主要采集参数如道距、覆盖次数、最大炮检距、接收线距和激发接收参数等进行了详细论证,然后根据论证结果选择2炮3线、单线480道接收的宽线观测系统进行了资料采集.与常规二维采集相比,宽线采集能较好地解决复杂山体区资料信噪比低,浅层反射弱和中、深层成像难的问题,所获得的剖面品质有较大幅度的改善.

Wide-line seismic acquisition technique and its application in complex mountainous area of Kuqa depression

Because of the complex surface and subsurface conditions as well as the poor shooting and receiving conditions encountered in seismic survey in the mountainous area of Kuqa depression, the acquired seismic data is low in S/N and difficult in imaging the subsurface structure. Aiming at this problem, we studied the wide-line seismic acquisition technique and applied it in western Qiulitage structural belt. Aiming at the complex geological and seismic conditions in the area, the technical countermeasures were proposed. Some basic parameters were evaluated, such as receiver interval, fold, maximum offset, receiver line interval, shooting and receiving parameters, and wide-line geometry was selected with 2 shots, 3 receiver lines, and 480 receiving traces on a line. The quality of the obtained profiles has been greatly changed, with much higher S/N in complex mountainous area and good imaging effect of the structure from shallow to deep underground.