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都兰县南部东昆中断裂带北侧的岛弧型变质火山岩系,变质程度自南而北从高绿片岩相增至绿帘角闪岩相,早期发育高角度逆冲变形,晚期受低角度走滑变形改造,变质顶峰与逆冲构造同步.变火山岩单颗粒锆石U-Pb年龄为（448±4）Ma.高角度逆冲变形带变质角闪石和白云母的40Ar-39Ar年龄分别为427±4和408Ma.上述年代学结果较为精确地限定了东昆仑造山带东段早古生代火山盆地关闭的构造年代,逆冲构造岩片的冷却速率约为9℃/Ma.
The island arc metamorphic volcanic rocks in the north of Dukunzhong fault zone in the southern part of Dulan County have metamorphic degrees increased from high-greenschist facies to greendish amphibolite facies in the south and north, and developed high-angle thrust deformation in early stage, The angle of the strike-slip deformation and transformation, the metamorphic peak synchronizes with the thrust structure, and the zircon U-Pb age of single-phase volcanic rocks is (448 ± 4) Ma.40Ar-39Ar ages of the metamorphic amphiboles and muscovites 427 ± 4 and 408Ma.The above chronological results more accurately define the tectonic age of the closure of the Early Paleozoic volcanic basins in the eastern segment of the Eastern Kunlun orogenic belt. The cooling rate of thrust strata is about 9 ℃ / Ma.