长江三峡地区三维重力反演研究

本文根据最新获得的长江三峡工程坝区及外围1/50万完全布格重力异常图和人工地震测深结果,利用Parker-Oldenburg快速位场反演方法研究了该区地壳深部结构.在计算过程中,通过采用模型分解、正则化及自下而上逐层反演等方法,首次获得了该区上、中、下地壳分界面的展布图象,并围绕着该区地壳深部构造的几个共同关心的问题讨论了它们的地质构造意义.

THREE DIMENSIONAL INVERSION OF GRAVITY ANO- MALIES IN THE REGION OF THREE GORGES, THE YANGTZE RIVER

Based on a new map of complete Bouguer gravity anomaly (1:500000) and recently obtained results of deep seismic sounding with explosion in the region of Three Gorges, the Yangtze River, the deep crustal structure in this region is studied using Parker-Oldenburg's formula of rapid inversion of potential field. In the process of study, the methods of model decomposition, regularization and layer by bayer inversion from bottom to top are utilized, from which the depth distribution of density interfaces between the upper, middle and lower crust in this region are first presented, and also their geological structure significance are discussed centring on a few problems about the deep crustal structure in this region.