Located in the middle of East Kunlun, the Bairiqili gabbro pluton consists of olivine gabbro, anorthosite and amphibolite gabbro. LA-ICP-MS zircon U-Pb dating suggests that the main fades hornblende gabbro intruded at 248.9 ± 4.2 Ma, being part of the Early Triassic magmatism during Paleo-Tethys ocean subduction. Based on previous researches, the authors hold that the Meso-zoic magma mixing in the East Kunlun orogenic belt started at least in Early Triassic, and that the Bairiqili pluton provides a window for the study of magma mixing at the subduction stage in East Kunlun. Meanwhile, a large number of inherited zircon ages indicate that East Kunlun basement underwent multi-stage and polycydic tectono -magma event in Precambrian, and the newly-discovered old age of 2109 ~ 2310 Ma may suggest that there existed another magmatic event in Early Proterozoic, whose geological significance deserves further researches.%东昆仑中段的白日其利基性岩体由橄榄辉长岩、斜长岩和角闪辉长岩组成.主体岩相角闪辉长岩的锆石LA-ICP-MSU-Pb年龄表明,其侵位于248.9Ma+4.2Ma,为早三叠世阿尼玛卿古特提斯洋关闭过程中的岩浆活动.结合前人的研究,认为东昆仑造山带中生代岩浆混合作用至少始于早三叠世,白日其利岩体为研究俯冲阶段岩浆混合作用提供了窗口.同时,白日其利辉长岩中大量继承锆石的年龄表明,东昆仑基底经历了前寒武纪多旋回多期次的构造热事件,其中新发现的2109～2310Ma的古老年龄指示东昆仑在古元古代时期还存在一期岩浆热事件,其地质意义有待进一步研究.
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