藏南岗巴-定日地区花岗岩单元特征及构造环境

岗巴。定日地区花岗岩属藏南拉轨岗日构造岩浆带的组成部分，岩石类型主要为似斑状二云母二长花岗岩、黑云母二长花岗岩、二长花岗岩、片麻状二云母二长花岗岩。通过1：25万区域地质填图，按照同源岩浆演化序列的观点，根据岩石学、岩石化学及地球化学、接触关系等特征，将该区花岗岩划分为5个单元，归并为1个超单元——佩古错超单元。研究表明，该超单元为S型花岗岩，在岩石学、岩石化学及地球化学组成上具有明显的同源岩浆演化特征，为形成于被动大陆边缘同碰撞构造环境的花岗岩。

The granite units and their tectonic settings in the Gamba-Tingri zone, southern Xizang

The granites in the Gamba-Tingri zone are arranged into the Lhagoi Kangri tectonic-magmatic belt in southern Xizang. The rock types consist dominantly of porphyroid two-mica monzonitic granites, biotite monzonitic granites, monzonitic granites and gneissoid two-mica monzonitic granites. The granites may be grouped, on the basis of petrology, petrochemistry, geochemistry and contacts, into five units, all of which are incorporated into one supraunit, i.e. the Paikuco supraunit. The study of petrology, petrochemistry and geochemistry shows that all the granites within the supraunit are assigned to the S-type granites and comagmatic granites formed in the syn-collisional tectonic settings on passive continental margins.