重磁电联合反演在银—额盆地勘探中的应用

COMBINED INVERSION OF GRAVITY GEOMAGNETIC AND ELECTRIC EXPLORATION IN THE YINGEN-EJINAQI BASIN

依据大地电磁测深连续二维反演结果初步确定构造与地层,通过综合分析区内物性特征给定地层与岩石的物性参数,建立正演地质—地球物理初始模型,在地质、钻井、地震资料约束下进行重磁电联合反演,不断修改地质—地球物理模型和大地电磁测深连续二维反演结果,使重磁正演数据和实测数据拟合度达到最佳。在银—额盆地构造与地层解释中的应用结果表明,重磁电联合反演可以有效克服单方法解释的多解性,准确识别地质层位,大大提高定量解释的精度。

Preliminary determination of structures and stratigraphy are achieved by two-dimensional inversion of successive magnetotelluric sounding. Based on overall analysis of stratigraphical and petrophysical parameters defined by regionally physical properties, a preliminary forward model of geology and geophysics has been created. Combined gravity and magnetoelectric inversion com- menced by geological, drilling and seismic data constantly revises the geological-geophysical model and the successive two-dimensional inversion result from magnetotelluric sounding, bringing the gravity-magnetic forward data and measured data to the most optimum fitting degree. Combined grav- ity and magnetoelectric inversion used for interpretation of tectonics and stratigrphy of the Yingen- Ejinaqi basin can effectively solve the problems derived from a single method and accurately indentify horizons of stratigraphy, thus greatly improving the accuracy of quantitative interpretation.