北疆区域地质调查阶段性成果与新认识

在介绍北疆沿国境线1∶25万区调修测项目阶段性成果基础上,据1∶25万区域地质调查新获得的地质事实与进展,结合区域性路线地质考查资料,对新疆北部准噶尔盆地东部阿尔曼太(扎河坝)蛇绿构造混杂带和准西部玛依勒山蛇绿岩带成因和构造背景提出新认识,初步认为阿尔曼太(扎河坝)蛇绿构造混杂带是华力西—印支期由南向北高角度逆冲推覆断裂铲起了早古生代(额尔其斯-卡拉麦里断裂间)增生杂岩楔(蛇绿岩块)推覆构造带；玛依勒山蛇绿岩带是具准洋壳特征的超基性岩、玄武岩及火山碎屑岩、硅质岩组合地层体,弱变形面状的分布,不具板块构造界线属性,表明其可能为哈萨克板块东南部陆缘裂谷中产物.

The Periodical Achievement and New Cognitions of Regional Geological Survey,Northern Xinjiang

On the basis of introducing the periodical achievement of 1:250 000 surveying project acrossing the border of northern Xinjiang,according to the geological facts and new progress that we got from 1:250 000 regional geological survey,and combining with the dates of territorial geologic investigation,we put forward a new theory to the gensis,tectonic setting of the Aermantai ophiolitic belt in the east Junggar area,Northern Xinjiang and the Mayileshan ophiolitic belt in the west Junggar area.We preliminary think that the Aermantai(Zhaheba) ophiolitic belt is a nappe structural belt(between the Ertix faulting belt and the Karamaili faulting belt) that is scooped up by high-angle thrust nappe fault from south to north during Variscan-Indonian Stage.We also think that the Mayileshan ophiolitic belt is a stratigraphic block(including ultrabasic rock,basalt,Pyroclastic rock and silicalite) that have the characteristics of quasi oceanic crust.It is Weakly Deformed and planar distributed.By the way,it does not have the properties of tectonic plate boundary,and may be it is the product of Epicontinental rift valley in southeastern Kazakhstan plate.