复杂构造条件下多煤层地震勘探新思路  

New Thoughts on Seismic Prospecting for Multi-seam Coal Area under Complex Structural Condition

作　　者：杨广宪 杨臣明[1] Yang Guangxian;Yang Chenming(Geophysical Prospecting and Research Institute,CNACG,Zhuozhou,Hebei 072750)

机构地区：[1]中国煤炭地质总局地球物理勘探研究院,河北涿州072750

出　　处：《中国煤炭地质》2018年第4期56-59,78,共5页Coal Geology of China

摘　　要：HDGD煤矿具有可采煤层较多、逆断层发育、断层交叉垂直、微小地质体发育等特点,常规的地震勘探方法难以解决此类复杂地质问题。通过对全方位观测系统优势比较,从小道距、小炮点距、小面元("三小")对地质体的分辨能力、炮点和接收点组合方式对分辨率的影响,数字检波器及激发层位对信号及能量的影响等方面进行分析,认为全方位角数字高密度三维地震勘探是构造复杂区获得高保真数据的有效手段。并以HDGD煤矿为例,介绍了三维波场分离法剔除规则干扰,分频剩余静校正、高密度双谱速度校正改善高频弱信号,叠前时间偏移改善大角度地层偏移成像等数据处理的效果。实例表明,全方位角高密度地震数据采集与处理技术在该矿的应用,可有效克服上覆高速层的屏蔽及高倾角断层的影响,清晰刻画其小断块和微幅褶皱等复杂构造影像。The HDGD coalmine has features of mineable multi-seam,developed reverse faults,vertically intersected faults,developed minor geologic bodies etc.,such complicated geological issues can not be solved easily by conventional seismic prospecting means.Through the comparison of omnibearing field setup dominant positions,carried out analyses of“three smalls”(small trace spacing,shotpoint spacing and surface element)resolution on geologic body,impact from array mode of shotpoint and receiving point on resolution and impact from digital geophone and shot horizon on signal and energy.The analyses considered that the omnibearing digital high density 3D seismic prospecting is an effective means to acquire high fidelity data in structurally complex areas.Taking HDGD coalmine as an example,introduced data processing effects from 3D wave field separation to eliminate regular interference,frequency division residual statics,high density bispectral velocity correction to improve high frequency weak signal and prestack time migration to improve high-dip strata migration imaging etc.The example has shown that the application of the omnibearing high density seismic data acquisition and processing technology in the coalmine can overcome impacts from overlying high-speed layer shielding and high-dip faults,depict complex structural images of minor fault block and microfold clearly.

关 键 词：全方位观测系统 多煤层 高倾角断层 数字检波器 三维波场分离法 叠前时间偏移 

分 类 号：P631.4[天文地球—地质矿产勘探]