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冰达坂韧性剪切带是西天山一条主要的地质构造带,是重要的地质成矿带。带内韧性剪切构造标志明显,是发育在地壳一定深度的高应变带,其变形环境与变形变质带的发生、演化的物理化学条件、环境、组分的迁移、运动方式及动力学等都有密切的关联,并根据其宏观和微观变形特征可以判别冰达版韧性剪切带的变形环境和变形时代。通过对冰达坂韧性剪切带不同部位的糜棱岩作石英光轴岩组图可以求出,最大主应力σ1≈92°∠10°,具左行剪切最大主应力σ2≈52°∠45°,右行剪切最大主应力σ3≈272°∠25°。采用数学方法,在冰达坂处横穿该韧性剪切带剖面的不同距离连续测量S-C夹角,求得剪切带总位移量S=2 912 m。其构造变形及演化大致可划分为早期韧性挤压剪切变形、中期走滑脆-韧性剪切变形和后期脆性变形作用等3个变形期次。
The Bingdaban ductile shear zone is one of the major geological tectonic belts in the Western Tianshan Mountains and is an important geological metallogenic belt. In-band ductile shear sign is obvious, it is a high strain zone developed at a certain depth in the crust, its deformation environment and the metamorphic zone of metamorphism, evolution of the physical and chemical conditions, environment, component migration, movement mode and dynamics are There is a close correlation between them. According to their macroscopic and microscopic deformation characteristics, the deformation environment and age of the ice-plate ductile shear zone can be distinguished. By using mylonites from different parts of the Bingdaban ductile shear zone as quartz optical axis, the maximum principal stressσ1≈92 ° ∠10 ° can be obtained, and the maximum principal stressσ2≈52 ° ∠45 °, the maximum principal stress σ3 ≈272 ° ∠25 ° of the right-hand shear. Using mathematical method, the S-C angle was continuously measured at different intervals across the ductile shear zone at Bingdaban, and the total displacement of the shear zone S = 2912 m was obtained. The tectonic deformation and evolution can be roughly divided into three deformation stages: early ductile extrusion shear deformation, medium-term strike-slip brittle-ductile shear deformation and late-stage brittle deformation.