Abstract: The features of deep conductivity structure along Xiangshui-Mandal Geoscience Transect are described in this paper basing on newly obtained magnetotelluric data. Large resistivity contrasts can be found on both borders of North China platform. The depth of the crustal high conductivity layer changes abruptly from 21km to 34km beneath Nei Mongol fold system on the northwestern end of the transect. While it is absent beneath Subei-Jiaonan terrane on the southeastern end of the transect,where two high conductivity layers are detected in the upper mantle. The crustal high conductivity layer is well developed in the Cenozoic basins within North China Platform with a relatively shallow depth. The depth of the upper mantle high conductivity layer along the transect ranges from 60 to 127kin,with a general tendancy of decreasing in depth from northwest to southeast,forming local uplifts beneath Ho-Bao basin,Central Hebei depression and Tan-Lu fault zone. It reflects the characteristics of the regional geology and the deep tectonic movements.

Key words: Geoscience Transect, Magnetotelluric measurements, High conductivity layer, Conductivity structure, Jiangsu, Nei Mongol

摘要： 本文着重介绍了响水一满都拉断面的深部电性结构特征。在华北地台北缘的构造边界两侧电性差异明显,壳内高导层埋深由21公里跃变到34公里;在南缘的郯庐断裂带及东侧壳内高导层缺失,上地幔出现两个高导层。在华北地台内新生代断陷盆地壳内高导层较为发育,埋藏较浅。上地幔高导层的埋深为60—127公里,总的趋势是西北深,东南浅,在呼包盆地、冀中拗陷和郯庐带下方形成局部上隆区,较好地反映了区域地质以及深部构造运动的特点。

关键词: 地学断面, 大地电磁测深, 高导层, 电性结构, 江苏, 内蒙