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在Shap花岗岩及热晕圈内,外侧围岩中,利用磁化率各向异性方法测定了50个点共280块岩心标本.花岗岩体内各个岩心标本的磁性组构均显示出不同大小磁铁矿颗粒的优选定向方位.这个组构是在岩浆缓慢上升和随之而发生的冷凝期间形成的.在紧靠Shap花岗岩接触面的变质岩中,磁性组构反映出在与花岗岩接触面近正交方向上存在有弱的轴向缩短.在热变质晕圈内,远离花岗岩的奥陶纪和志留纪岩石具磁性组构扁椭球体,其陡倾的磁性面理走向大致为NE-SW向,平行于区域加里东劈理面.这说明在花岗岩内观测到的磁性组构是与岩浆侵位时间有关的原生产物,而岩浆侵位发生于加里东造山运动的主压作用期后.花岗岩对围岩的影响主要是热变质和仅限于花岗岩体周围很窄范围内的机械变形.
In Shapa granite and thermal halo, in the outer surrounding rock, the magnetic susceptibility anisotropy method was used to measure a total of 280 core samples at 50 points.The magnetic structure of each core sample in granite showed different size of magnetite particles This formation is formed during the slow rise of the magma and consequent condensation In the metamorphic rocks abutting the Shap granite contact, the magnetic fabric reflects a nearly normal orientation in the interface with the granite There is a weak axial shortening in the thermal metamorphic halo, away from the granite of the Ordovician and Silurian rock with magnetic structure of flat ellipsoid, the steep magnetic orientation of the roughly NE-SW direction, parallel In the area of Caledonian cleavage surface.This indicates that the magnetic structure observed in granite is the primary product related to magma emplacement time and magmatic emplacement occurred after the main pressure period of Caledonian orogenic movement.The granite pairs The influence of the surrounding rock is mainly thermal metamorphism and limited to mechanical deformation within a narrow range around the granite.