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西藏高原南部花岗岩类分布广泛,规模大,可明显地划分出呈北西西向分布,形成时代由北向南逐渐变新的三个岩带,即冈底斯岩带、拉轨岗日岩带和喜马拉雅岩带。 上述岩带的同位素地质年龄测定,主要是用钾-氩法测定云母年龄和用铀-铅法测定锆石年龄。两种方法所用矿物,是选自同一个岩石样品,这样对部分岩体时代的确定更为准确。结合年龄测定所做的黑云母矿物的初步研究,发现西藏南部花岗岩类中黑云母存
The southern granites in the southern Tibet Plateau are widely distributed and large in size, and can be clearly divided into three NWs that change from NWW to NW and formed gradually from north to south, that is, the Gangdise zone, the RAGG and the Himalayas Rock band. The isotopic geologic ages of these rocks are mainly determined by the potassium-argon method for the age of the mica and the zircon age by the uranium-lead method. The minerals used in the two methods were selected from the same rock sample, thus making the identification of some rock age more accurate. Based on the preliminary study on the biotite minerals determined by age, it was found that the biotite deposit in the southern Tibet granite