镇巴复杂山地地震采集质量影响因素分析

Analysis on factors affecting seismic acquisition quality to complexmountainous exploration in Zhenba block

中国石化集团胜利石油管理局地球物理勘探开发公司 山东东营 257100

Geophysical Exploration and development Corporation of Shengli Petroleum Administrative Bureau, Dongying 257100, China

镇巴区块二维地震资料信噪比低,因此,提高信噪比是该区地震勘探的重要研究内容之一。通过对镇巴区块地震地质条件和二维地震资料的研究,重点分析了影响地震采集质量的各种因素,认为:①地表和地下地质结构的双重复杂性是造成镇巴区块地震采集质量变差的根本原因;②干扰波发育、激发岩性差、激发点位置和激发参数选择困难以及检波器组合、观测系统设计的局限性是镇巴区块地震采集质量变差的直接原因。提出了相应的改进措施:①现有条件下改进地震采集质量提高信噪比的办法是,加强表层结构调查和深部构造研究,重视干扰波分析,优化观测系统设计和激发、接收参数选择等;②强化对复杂构造和复杂地震波场的认识,研究和探索新方法新理论,是改变镇巴区块地震成像质量的根本途径。

Seismic data shows low S/N ratio in Zhenba block. By researching seismic geologic condition and 2Dseismic data, the factors affecting seismic acquisition quality are analyzedmainly. Results show that the double complexity of surface condition and underground structure is fatal cause. Direct causes include strong noise, bad explosive rock, the difficulty of choosing shot point position and shooting parameters as well as the limit of geophone array and layout design. Correspondingmethods improving seismic acquisition quality are proposed as following: strengthening investigation of surface and underground geologic structures, payingmore attention to interference wave analysis, optimizing layout design and shot receiving parameters; the essential path to change seismic imaging are improving recognition to complicated geologic structure and seismic wave as well as studying newmethod and theory.