中国西北地区柴北缘赋煤区构造单元新厘定

A new division of the structural units of the north Qaidam coal zone in northwest China

为对柴北缘赋煤区构造单元进行重新厘定,文章基于煤田地质构造特征并集成前人研究工作成果,从区域构造控制与煤系赋存状况相结合的角度对柴北缘赋煤区构造单元进行了深入研究,认为柴北缘赋煤区可新厘定为""三隆三凹(五小凹区)"即3个三级单元,11个四级单元,具体为:1东部构造分区。整体地貌呈现三隆夹两凹的构造形态,3条隆起从南至北依次为绿梁山-锡铁山-埃姆尼克山、欧龙布鲁克山山前断裂和宗务山隆起条带,2个凹陷由南向北为乌兰凹陷和德令哈凹陷;2中部构造分区。该中间构造分区整体构造形态为两隆两凹,2个凹陷一为绿南凹陷一为鱼卡-红山凹陷,前者为低应变区,褶皱构造发育,后者为高应变区,为主要含煤区段;两个隆起是交叉归并隆起,南为欧龙布鲁克山-牦牛山隆起带,北为达肯大坂隆起带,二者在羊肠子沟一带逐渐归并为一;3西部构造分区。本区整体构造格局为一隆一凹,山前凹陷处于柴达木盆地边缘,沉积厚度较厚,而绿南凹陷的西部区域也同赛南凹陷处于同一盆地区带。该研究是首次从煤田地质角度对柴北缘赋煤区构造单元的新厘定。

On the basis previous work such as the coalfield tectonic features, regional tectonic control and coal reserves condition perspective, the paper divides the coal zone of northern Qaidam into three units in large scale and eleven units in small scale. The result is：（1）Eastern Structure Division：From south to north there are three uplift belts, the Lveliangshan-Xitieshan-Aimnikeshan uplift belt, the Oulongbuluke- shan-Maoniushan uplift belt, and the Zongwulongshan uplift belt, the structural pattern is three uplift belts and two depression basins. （2）Central configuration partition ： Because of the merge of the Oulongbulukeshan-Maoniushan uplift belt and Dakedaban uplift belt, the structural pattern shows two uplift belts and two depression basins, in the north is North Qaidam major coal-bearing zone named as Yuka-Hongs han depression basin,and in the south is low strain region, the fold is developing. （3）western construct Subdivision ： Because of the merge of the Xitieshan-Aimunikeshan uplift zone and the Saishitengshan uplift zone,the structural features exhibit one uplift belt and depression basin,the Sainan depression zone in the southern mountain,the Jurassic sedimentary is deep,also at the edge of the Qaidam Basin, and the Lvnan west extension of the recess. The new determined tectonic units study is the first from the perspective of Coalfield Geology in North Qaidam coal areas,which is a very important practical significance.