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集中于青藏高原东南缘澜沧江走滑挤压带应变路径与应变分解关系的探讨,该剪切带出露各类型韧性变形岩石,为有限应变、运动学涡度值和单剪-纯剪组分比率的定量化分析提供地质条件.平均运动学涡度值的估算基于3种传统方法,即Rs-θ法、碎斑双曲线分布法和极摩尔圆法;计算结果表明低级片岩带内的糜棱岩化变质沉积岩平均运动学涡度为0.19~0.54,高级片麻岩带的初糜棱岩、糜棱岩和超糜棱岩的运动学涡度值分别为0.19~0.73,0.11~0.8和0.84~0.95(甚至高达0.99).利用经典应变分析方法和运动学涡度值估算结果一致暗示澜沧江剪切带总体为单斜对称应变.结合运动学路径,该剪切带可以被厘定为典型的走滑挤压应变带、且发生了应变分解.根据区域构造背景,青藏高原东南缘展布的这些新生代陡立而狭窄的大型韧性剪切带是调节陆内变形过程中简单剪切组分的重要地质载体,而纯剪切组分则分解在构造带外侧更宽阔的地体上.
Discussion on the relationship between strain path and deformation in the Lancangjiang strike-slip extrusion zone in the southeastern margin of the Qinghai-Tibet Plateau reveals various types of ductile deformation rocks, which are finite strain, kinematic vorticity values and shear-pure shear components The quantitative analysis of the ratios provides the geological conditions.The average kinematic vorticity estimation is based on three traditional methods, the Rs-θ method, the patch hyperbolic distribution method and the pole-mole-circle method. The calculated results show that the min- The average kinematic vorticity of the marginalized metamorphic sedimentary rocks is 0.19-0.54. The kinematic vorticity values of the early mylonites, mylonites and supermylonites in the advanced gneiss belt are 0.19-0.73 and 0.11-0.8, respectively 0.84 ~ 0.95 (even up to 0.99) .The results of classical strain analysis and kinematic vorticity estimation consistently imply that the shear band of the Lancangjiang River is generally monoclinic, and this shear band can be determined as a typical Slipping and compressing the strained zone with strain decomposition.According to the regional tectonic setting, the large and sharp steep and narrow ductile shear zones distributed in the southeast of the Qinghai-Tibetan Plateau are the simple shear components in the intracontinental deformation Important geological Body, and pure shear component decomposition in construction with the outside of the body wider.