三维重磁电震资料的联合解释——以库车大北地区山前砾石层为例

Integrated interpretation of 3D gravity,magnetic,electromagnetic and seismic data:a case study of conglomerate mass investigation in piedmont area of Kuche Depression

库车拗陷山前带广泛分布砾岩体,严重影响地震资料深层的构造成像和解释精度。在库车大北地区开展的三维重磁电勘探工作,结合钻井、地震、地面露头资料,尝试采用多方法综合解决砾石层分布及岩性岩相变化。通过三维电法资料反演处理,实现了电法与地震资料同平台的联合解释,使综合解释由简单定性对比发展为联合精细描述,通过主干剖面的联合反演确定了不同层系的砾石层空间分布和砾岩岩性、岩相变化特征,为重新认识盐下构造,落实勘探目标及速度建模提供了依据。

In piedmont area of Kuche Depression,widely developed conglomerate masses seriously disturb seismic image and interpretation of deep structures.So integrated 3D gravity,magnetic and electromagnetic survey in the area was planned with the purpose of investigating conglomerate mass and its variation of lithology and lithofacies with the reference of logging data,seismic data and outcrops information.With improved approaches of data processing,3D EM data is integrated with seismic data on a united platform.This makes an integrated interpretation change from a simple qualitative comparison way to a more accurate study.A joint inversion on major sections gives the spatial distribution of conglomerate masses formed in different time.It provides bases for the investigation of subsalt structures,and velocity model building.