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江山 绍兴碰撞带北段诸暨 绍兴一带磁化率各向异性研究表明 :碰撞带内不同类型的变质岩、沉积岩的磁组构均具有最小磁化率主轴最集中的特点 .磁组构最小磁化率主轴的平面投影表明 ,这一地区的主压应力方向为北西 30～ 6 0°,集中于陈蔡北西～南东方向 ,主压应力往南北两侧璜山和王家宅呈弧状散开 ;最小磁化率主轴倾角显示 ,华夏地块往北西方向推移 ;最大磁化率主轴相对比较分散 ,但尚在置信圆内 ;最大磁化率主轴与线理呈小角度相交 ,指示了江山 绍兴碰撞带还具有左旋平移的特征 .不同时代岩石磁组构的对比结果显示 ,江山 绍兴碰撞带的最后强烈碰撞的时间为晚三叠世之后至晚侏罗世 ,而后以左形剪切走滑持续到燕山期末 .
The magnetic susceptibility anisotropy of the Zhuji-Shaoxing area in the north of the Shaoxing collision zone in the Jiangshan Mountains shows that the magnetic structures of the different types of metamorphic rocks and sedimentary rocks in the collision zone have the features that the minimum magnetic susceptibility is the most concentrated. The plane projection shows that the principal compressive stress direction in this area is 30-60 ° northwest, concentrating in the north-west direction of Chencai, and the main compressive stress diffuses to the north and south sides of Huangshan Mountain and Wangjiazhai. The minimum magnetic susceptibility The dip angle of the main axis shows that the Huaxia block moves northwestward. The maximum magnetic susceptibility axis is relatively scattered, but still within the confidence circle. The maximum magnetic susceptibility axis intersects the line at a small angle, indicating that the Shaoxing collision zone has a left-lateral translation The comparison of magnetic fabric in different ages shows that the last strong collision of the Shaoxing collision zone in Jiangshan was from the Late Triassic to the Late Jurassic, and then left-shear shear strike continued to the end of Yanshan.