西藏自治区北部１∶２５万多巴区幅位于冈底斯—念青唐古拉板片的北缘（图１），笔者在进行该幅野外地质调查时，在永珠超基性岩带以北申扎县雄梅乡以东的拉赛一带发现了一套早古生代地层———拉赛灰岩，并对其进行了初步研究。据拉赛灰岩路线剖面（图２），该套地层层序如下 The 1: 200,000-waiba area in the northern Tibet Autonomous Region is located on the northern margin of the Gangdise-Nyainqntanglha Plate (Figure 1). During the field geological survey, the author applied north of the Yongzhu ultrabasic belt A set of Early Paleozoic strata --- Lhasa limestone was found in the area of ​​Lhasai, east of Xiong Meixiang, Zhaoxian County, and a preliminary study was conducted on it. According to Lhasa limestone line profile (Figure 2), the set of stratigraphic sequence is as follows