摘要
中天山卡瓦布拉克一带,受长期掀斜隆升剥蚀,显示古地壳具层圈结构。盖层为火山岩,由于剥蚀局部残留,上地壳由劈理带和结晶片岩带组成;中地壳为塑性流变层,由板状韧流带和环状重熔岩带构成;下地壳仅见呈热隆上升的环状中基性杂岩体。板状韧流带具大型韧性剪切变形特征,中基性杂岩体为下地壳热隆岩浆上升,并使中地壳岩石形成重熔型花岗岩,共同构成环状杂岩体。该地壳层圈结构形成于新疆古大陆震旦—寒武纪裂解及准噶尔洋盆发育过程中。
The long-term uplift and erosion reveal that the paleo-crust of the middle Tianshan mountains in Kawabulake has a feature of layered structure. The cover rocks are volcanic rocks. The localized relics after erosion show that the upper crust is composed of a cleavage zone and a crystalline schist zone. The middle crust with plastic deformation consists of a platy ductile flow zone and a ring-shaped re-melting zone. The latter is characterized by large-scale ductile shearing. Only ring-shaped intermediate-basic complexes are visible for the lower crust, which are caused by re-melting of the rocks of the middle crust due to the thermal up-warping. The crust structures resulted from the opening of Junggar oceanic basin due to the separation of paleo-continent of Xinjiang during the Sinian-Cambrian, and uplift of the middle Tianshan mountains.
出处
《新疆地质》
CAS
CSCD
2002年第4期352-356,共5页
Xinjiang Geology
基金
中国地质调查局国土资源大调查项目(DKD9902002)资助
