叠前时间偏移方法在煤田勘探中的应用  

Application of Prestack Time Migration in Coalfield Exploration

作　　者：冷广升[1] 陈加林[1] 王秀荣[1] 杜宏[1] 车建英[1] 朗玉泉[1] 

机构地区：[1]中国煤炭地质总局物探研究院,河北涿州072750

出　　处：《中国煤炭地质》2008年第6期40-43,共4页Coal Geology of China

基　　金：国家重大产业技术开发专项项目资助(发改办高技[2005]1255)

摘　　要：根据克希霍夫积分法的原理,介绍了叠前时间偏移的方法特点,实现过程,以及对地震资料的要求,依托国家重大产业技术专项"西部煤炭资源高精度三维地震勘探"工程,对"青海省鱼卡煤田四井田高精度三维地震勘探"资料进行叠前时间偏移,结果表明其能较好地解决成像质量差、能量聚焦不明显、绕射波收敛不理想等方面的难题。通过与叠后时间偏移对比,对于大倾角地层、断块小且多的破碎带、陡倾角不对称向斜等地质问题,其叠前时间偏移剖面成像质量都有明显的提高,反映的构造关系更加清晰,同相轴连续性增强。总结该方法在多个矿区的推广经验,认为合理的观测系统、较高的资料信噪比,准确的测量资料及较高的中表层速度调查精度是做好叠前时间偏移的前提。Based on Kirchhoff integral principle, introduced prestack time migration methodic peeuliarity, implementation proeess and requirements on seismic data. Rely on the state major industrial technological development special project ＂Western China Coal Resource High Precision 3D Seismic Prospecting Technology＂ carried out prestaek time migration for high precision 3D seismic prospecting data from No.4 minefield, Iqe eoalfield, Qinghai Province, the results have demonstrated that it can solve hard nuts all the better including poor imaging, inconspieuous energy foeusing, imperfect diffraeted wave convergence etc. Contrasting with poststaek time migration, imaging quality of prestack time migration improves obviously in areas of high dip angle strata, fracture zone with smaller and abounding crushed blocks, steep-dipping asymmetric synelines, reflected structural relations clearer, phase axis continuity improving. Summarized the method popularization experiences in many mining areas, considered that rational field setup, higher data S/N ratio, correct measured data and higher medium and near surface veloeity precision are preconditions to make better prestack time migration.

关 键 词：叠前时间偏移 信噪比 三维地震勘探 青海省鱼卡煤田 

分 类 号：P631.4[天文地球—地质矿产勘探]