雅鲁藏布缝合带吉定蛇绿岩中的均质辉长岩与堆晶辉长岩呈过渡关系,是研究区特提斯洋壳轴下岩浆房过程的产物.对其进行SHRIMP锆石U-Pb定年,得出加权平均年龄为128±2Ma(2σ,MSWD=0.71),即辉长岩结晶年龄.该结果代表了吉定地区特提斯洋海底扩张的时代,与中段大竹卡洋盆形成时代一致,但晚于东段和西段洋盆发育时代,表明藏南日喀则地区洋盆时代相当,而整个东特提斯洋盆发育消亡时代存在差异. The homogenized gabbros in the Jiading ophiolite of the Yarlung Zangbo suture have a transitional relationship with palygorskite and are the product of the magmatic chamber under the Tethys oceanic crust in the study area.The SHRIMP zircons U-Pb dating, the weighted average age is 128 ± 2Ma (2σ, MSWD = 0.71), ie, the gabbro age. This result represents the age of the Tethys ocean seabed expansion in the Jiding area, The formation age of the basin was the same, but later than that of the oceanic basin in the eastern segment and western segment, indicating that the oceanic basin was similar in the Xigaze region in southern Tibet and that there was a difference in the era of the development and disappearance of the entire Eastern Tethys Ocean basin.