重磁电震资料联合反演黔中隆起物性结构

Determination of Physical Property Parameters Structure in Middle Guizhou Uplift by Joint Inversion of Magnetotelluric,Seismic,Gravity and Magnetic Data

黔中隆起区地形和构造复杂,地震勘探难度大,资料品质受到一定影响.因此,利用大地电磁测深(MT)资料并结合重力和磁力资料,通过联合反演来重点解决研究区下古生界目的层的分布及基本构造特征.在物性研究基础上,建立该区基本的物理-地质模型.利用MT与地震资料的模拟退火约束同步反演技术,对黔中隆起实际采集的MT资料和地震数据进行了处理,并结合重磁力资料进行了顺序反演和综合解释,确定了该区基本的速度、电性、密度和磁性结构,为构造研究提供了全面和可靠的依据,证明了联合反演技术的有效性和实用性.

The studied area was difficult for seismic prospecting construction and the reflection quality was not quite good as a result of the topography and complicated structure. Therefore, based on magnetotelluric （MT）,seismic and gravity ＆ magnetic data,joint inversion technique was used to study the distribution of target strata especially the lower Paleozoic and basic structural features. Basic physicalgeological models of the studied area were set up in accordance with physical properties study and statistics. Based on the studies of simulated annealing algorithm and joint inversion methods, the field observed data of MT and seismic in the area of middle Guizhou uplift were processed on the basis of constraint synchronous joint inversion technique of MT and seismic data versus simulated annealing algorithm. Then the sequent joint inversion based on gravity ＆ magnetic data and the final integrated interpretation were put forward, and the velocity, electrical, density and magnetic structures of the studied area were determined, providing reliable basis for geological structure studies. The application of joint inversion using different geophysical data proved effective and practical in this area.