阿尔泰-准噶尔北缘重磁场特征及其断裂的地质意义

阿尔泰-准噶尔北缘成矿带富含铁、铜、镍、金等多种矿产资源, 但准噶尔周缘的构造单元及断裂划分存在一定争议, 从而影响了找矿部署方向研究。为进一步深化区域成矿规律的研究, 优选大型、超大型找矿远景区开展物探勘查, 笔者收集了最新、最大比例尺的重磁资料和大量的物性信息, 以地球物理重磁理论为指导, GIS技术为手段, 对阿尔泰-准噶尔北缘成矿带的重力和磁场特征进行了详细的分析, 并对阿尔泰-准噶尔北缘断裂及准噶尔盆地西缘断裂进行推断解释。认为准噶尔北缘断裂与准噶尔盆地的西缘断裂为2条性质完全不同的断裂, 东西准噶尔不具对比性, 准噶尔北缘断裂主要以北西西向构造为主。提出准噶尔陆块边界的边界应是塔城—和布克赛县一线以西, 西准噶尔和卡拉麦里相似, 只是准噶尔陆块中的局部隆起。

Characteristics and Geological Significance of Gravity and Magnetic Field and Faults in the North Margin of Altay-Junggar

There are many mineral resources in the north margin of Altay-Junggar, such as iron, copper, nickel, gold, etc. However, there are some disputes around Junggar about tectonic units and faults division affecting prospecting direction. To further deepen the study of regional mineralization regularity, the newest and largest scale gravity and magnetic information were collected; with the guidance of geophysical gravity and magnetic theory, the authors analyzed characteristics of the gravity and magnetic field by GIS technology, and interpreted the faults in the north margin of Altay-Junggar and the west margin of Junggar. Results show that the two faults were completely different in terms of properties, and there is nothing comparable between east and west Junggar. The fault in the north Junggar is mainly NWW-trending. It is concluded that the Junggar continental boundary should be to the west of Tacheng-Hebukesai. Similar to west Junggar and Calamaili, it is just a local uplift in the Junggar block.