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都古尔片麻岩是最近发现和确定的一个非正式岩石单位 ,是西藏羌塘地区目前唯一确定的片麻岩产地 ,由花岗质片麻岩和角闪斜长片麻岩组成 ,两类片麻岩均发生韧性变形。选择变形较弱的花岗片麻岩进行了同位素年代学研究 ,获得单颗粒锆石U -Pb谐合线年龄 384 4Ma ,黑云母4 0 Ar -3 9Ar坪年龄 135 9Ma ,认为都古尔花岗岩 (片麻岩 )在相对稳定的环境中缓慢冷却 ,侏罗纪末、白垩纪初 (135Ma± )抬升到距地表约 10km处 ,与羌塘盆地转换期一致。羌塘地区目前还没有发现和确定存在古老结晶基底
Dugugu gneiss is an informal unit of rock recently discovered and identified and is the only gneiss origin in the Qiangtang region of Tibet. It is composed of granitic gneiss and amphibifer gneiss, Tantalite-like ductile deformation occurred. We selected isotope geochronology to study the isotopic geochronology of granitic gneiss with weaker deformation, and obtained the age of 384 4 Ma of single grain zircon U-Pb and 135 9 Ma of 4 0 Ar -3 9Ar of biotite, (Gneiss) slowly cooled in a relatively stable environment. At the end of Jurassic and Early Cretaceous (135Ma ±), it rose to about 10km from the surface and was consistent with the conversion period of Qiangtang basin. The ancient crystalline basement has not yet been found and confirmed in the Qiangtang area