二连盆地重磁异常地质意义及上古生界结构认识

Geological implications of gravity and magnetic anomalies in Erlian Basin and understanding of Upper Paleozoic structures

二连盆地为我国一个中型油气区。本文在对研究区重磁资料统一拼接、处理基础上,通过分析重磁资料反映的地质结构信息,结合区域地震资料,推断了该区上古生界地质结构。综合研究认为,二连盆地上古生界受深大断裂控制,在西拉木伦河断裂以北上古生界残余厚度较大,并形成两个厚度中心,即二连—苏尼特右旗厚度中心和西乌珠穆沁旗—东乌珠穆沁旗厚度中心。前者厚度为3000m,后者上古生界厚度大、分布广,最厚可达6300m,是后续研究的重要目标区。

Erlian Basin is a middle-scale oilfiled of China.Our work in the basin is as follows:merging and process gravity and magnetic data acquired in the basin,analyzing the geological implications of the data,and finally predicting Upper Paleozoic structures together with available seismic data.The comprehensive study concludes that Upper Paleozoic formations are dominantly controlled by big deep faults in the basin.In the north of the Xilamulun-River fault,the residual Upper Paleozoic formations have the big thickness.There are two thickness centers,i.e.Erlian-Suyouqi Zone and Xiwuqi-Dongwuqi Zone.The maximum thickness of the former is about 3000 m,and the maximum thickness of the later is about 6300 m.Both of them have not only big thickness but also a wide coverage,and are considered as future potential targets.