新疆西昆仑库木别勒沟一带石炭-二叠系地层划分

西昆仑库木别勒沟一带地层单位划分与厘定争议已久.通过1∶5万区域地质调查,在库木别勒沟一带发现一套深色浅变质含砾细碎屑岩夹碳酸盐岩及火山岩建造,沉积环境为浊流沉积.并在其下部灰岩内首次发现含珊瑚、腕足及海百合茎类化石;岩层内包含有下志留统中的大理岩砾石或块体,其形成时代要晚于下志留统.根据区域地层对比和化石,新划分为上石炭统—下二叠统喀拉塔什组(C2-P1k),另据岩石组合特征,该组自下而上划分为一段和二段两个段,这一地层单位的合理确立,为区域地质填图建立了正确的岩石地层单位,并为本区的地层划分和区域对比提供了新的依据.

Carboniferous Permian Stratigraphic Division of Kumubielegou Area in West Kunlun Xinjiang

The division and confirming of strata in Kumubielegou of West Kunlun is controversial for a long time. A suit of dark low-grade pebbly fine clastic rock with carbonate rock and volcano rock formation building was discovered in the Kumubielegou area using 1 ： 50 000 regional geologic and mineral surveying, and the sedimentary environment was turbidity deposition. Fossil with coral, brachiopods and crinoids was discovered for the first time in the lower limestone. And marble gravel or block was found in the rock of Lower Silurian, whose formation age is later than Lower Silurian. According to the regional stratigraphic correlation and fossil, the strata in Kumubielegou was divided into the upper Carboniferous Lower Permian Aktashi form （C2-P1k）. And according to the rock association characteristics, the form was divided into a segment and a two segment two segment. The reasonable establishment of the stratigraphic units, is helpful to establish the right lithostratigraphic unit for regional geological mapping, and affords a new basis for the stratigraphic division and regional correlation in this area.