NEW IDEAS OF THE UPPER SILURIAN AKEYAZI AND QIONGKUSHITAI FORMATIONS ON THE NORTHERN SLOPE OF THE HALIK MOUNTAINS

The amphibolite facies metamorphic rocks of the Upper Silurian Mountains are possibly ofEarly Proterozoic age,making up the basement of the Yining-central Tianshan plate. The UpperSilurian Qiongkushitai Formation is a " metamorphosed subduction complex" （metamorphosedmelange）composed of greenschist,blueschist and minor marbleized limestone lenses and ophiolitenappe slabs.