北祁连山出露有我国目前唯一的一条Ⅱ型高压低温变质带,为含石英、硬玉质辉石、蓝闪石和铝石榴子石(富锰或富铁、富钙)等特征矿物的蓝闪榴辉岩。近年对蓝闪榴辉岩的研究,已获得如下认识: (一)和蓝闪片岩一样,北祁连山蓝闪榴辉岩也可分作三条带出露:阿克龙娃沟-清水沟-红桥带,大柳沟脑-白杨沟-百经寺带和百泉河-桦木沟带。野外观察蓝闪榴辉岩呈透镜状、条带状出露于蓝闪片岩带中,而蓝闪片岩带往往和蛇绿岩带共存。蓝闪榴辉岩出露处,一系列逆冲断层发育。可依此划分出若干岩片,自断层面起,由下而上是蛇纹岩(或蓝闪榴辉岩)、蓝闪片岩、钠长阳起片岩和绿帘角闪片岩。 (二)岩石化学特征数值研究表明,北祁连山蓝闪榴辉岩原岩种类较多,主要是基性火山岩,也有 The northern Qilian Mountains are the only type Ⅱ high-pressure and low-temperature metamorphic belt in our country that is blue-green grenadier containing quartz, mafic pyroxene, glaucophane and aluminum garnet (rich in manganese or iron-rich, rich in calcium) Hui rock. In recent years, the research on blue eclogite has gained the following recognition: (1) Like the blue flash schist, the blue Qilian eclogite in the North Qilian Mountains can also be divided into three zones to be exposed: Arkongwa Gully - Gully - Red Bridge, Daliu Gully brain - Poplar ditch - Hundred Temple Temple and Bai Quanhe - birch groove. In the field observation, the blue flash eclogites are lenticular and banded out in the blue flash schist belt, while the blue flash schist belt often coexists with the ophiolite belt. Blue eclogite eclogites, a series of thrust faults. According to this, a number of rock fragments can be divided. From the bottom up, there are serpentinite (or blue-flash eclogite), blue flash schist, sodium Changyangqi schist and green-curtain hornblende. (B) Numerical studies of petrochemical characteristics show that the blue-flash eclogites in the Qilian Mountains have more protoliths, mainly basic volcanic rocks and