中文摘要：

本文利用跨越河套盆地及其南部鄂尔多斯块体与北部阴山山系地域的高精度实测重力数据，构建了研究区深部地壳密度结构模型，从壳内各界面与Moho界面的展布、地震活动性、资源与能源分布等方面探讨了该区的深部构造特征及其响应，并结合其它已有研究结果分析了造成现今构造格局的地球动力学机制．研究结果表明：河套盆地的地壳密度结构与鄂尔多斯盆地和阴山造山带地域存在显著差异；在河套盆地下方的基底埋深可达7～8km，且Moho界面在该处抬升约3～4km．岩石圈地幔物质在河套盆地下方的上涌不仅导致了Moho界面的抬升，亦使该盆地下方柔性下地壳密度略高于其两侧地域，而脆性上地壳中的深断裂则为地震的发生与金属和非金属矿产资源的形成提供了场所与环境．这一地带的地震分布特征显示出河套盆地与阴山造山带南部在整体上构成了鄂尔多斯盆地与阴山造山带的盆山耦合过渡区．

英文摘要：

In this study, the density model of the crust beneath the Hetao basin and its adjacent areas was constructed based on the gravity anomalies measured along a profile crossing the Hetao basin, extending from the north part of Ordos basin to Yinshan orogen. The deep tectonic characteristics and its geodynamic responses were discussed from the viewpoints of the undulation of the Moho and other interfaces in crust, characteristics of earthquakes occurrence and the distribution of mineral resources and energy field, based on the crustal density model obtained in this study. The research results suggest that, there exist obvious differences in crustal density structure between the Hetao basin, Ordos basin and Yinshan orogen. Beneath the Hetao basin, the crystalline basement is as deep as 748 kin, and the Moho interface there is 3--4 km shallower than its two sides. Upwelling of the materials from the lithospheric mantle results not only in the uplift of the Moho interface, but also in the formation of higher density zone in the ductile lower crust beneath the Hetao basin. Meanwhile, the deep faults in the brittle upper crust have provided good environment for the occurrence of earthquakes and formation of the mineral resources. In addition, the distributional characteristics of earthquakes imply that the coupling zone between the Ordos basin and the Yinshan orogen consists of both the Hetao basin and the south part of the Yinshan orogen.