重磁联合反演解释在长白山天池深部构造中的应用

重磁联合反演可以解决火山岩强反射屏蔽作用导致地震深层反射能量弱的问题。为了解译长白山天池深部断裂构造并描述地层形态,笔者依托Oasis Montaj重磁拟合平台,参考地震地质资料建立原始重磁模型,并利用岩性参数作为约束条件进行联合反演解释。根据布格重力异常与地磁法异常分布特点,成功反演了地下8 km基底范围内的地层分布特征,解译了7处断裂分布位置。其中深大断裂位置与地质、遥感研究结果能够良好吻合,并更加精确。

Application of joint inversion interpretation of gravity and magnetism in Tianchi deep structure of Changbai Mountain

Joint inversion of gravity and magnetic can solve the problem of weak reflection energy for deep seismic caused by volcanic strong reflection shielding effect． In order to interpret deep faults and describe the for- mation pattern in Changbai Mountain，the authors relied on Oasis Montaj gravity and magnetic fitting platform and seismic geological data to create the original gravity and magnetic model，and lithological parameters were used as constraints to joint inversion interpretation． According to the distribution characteristics of geomagnetic and Bouguer gravity anomalies，the authors inversed the stratigraphic distribution within underground 8 km，and interpreted the fracture distribution at 7 locations． Among them，the location of deep and large fault matched well with the results of geological and remote sensing research，and in higher precision．