重磁电资料在合肥盆地构造分区中的应用

Application of gravity and magnetic data in structural zoning of the Hefei basin

依据合肥盆地的高精度重力、航磁和大地电磁测深等地球物理资料处理,通过地层密度、磁性和电性等物性特征的分析,开展多学科的综合研究,初步确定了盆地的断裂展布及中、新生代地层发育特征,认为合肥盆地构造平面展布大体上可看作"周坳围中隆"的构造格局,将盆地划分为四个一级构造单元,进一步划分为十个二级构造单元,为丰富盆地构造分析提供了综合地球物理信息。根据各构造单元的地球物理特征和石油地质条件,指出六安低凸起和蜀山断裂带为盆地内有利的油气富集带。其中防虎山构造、小庙构造、木厂埠构造和小庙断块等为油气运移的指向,该带成为盆地有利勘探目标之一。

Based on the processing of geophysical data such as high-precision gravity, aeromagnetism and telluric electromagnetic sounding, this paper analyzed physical features as stratum density, magnetic and electrical properties, made a multidisciplinary study and preliminarily determined the distribution of faults and Mesozoic and Cenozoic strata development in the basin, thought that the Hefei basin is roughly structurally a framework of the ＂Depressions Surround Central Rise＂, dividing the basin into four primary structural units, which are then sub-divided into ten secondary units. According to geophysical features and oil geology conditions of each unit, it is suggested that the Lu＇an low rise and the Shushan rifting zone are favorable oil-gas enrichment zone bu structures and the Xiaomiao rifting block indicate the in the basin, in which the Fanghushan, Xiaomiao, Muchang-direction of oil and gas movement, therefore this zone becomes one of targets favoring exploration.