鲁西地区韧性剪切带岩石磁组构分析及其构造意义

ANALYSIS OF ROCK MAGNETIC FABRIC FROM DUCTILE SHEAR ZONES IN WESTERN SHANDONG AND ITS TECTONIC SIGNIFIANCE

岩石磁组构分析可用来研究岩石的组构特征及构造变形。鲁西地区韧性剪切带岩石磁组构具有磁各异性度Ｐ和磁百分率各向异性值Ｈ高、磁化率量值椭球呈压扁状、磁面理发育而磁线理不发育的特点。区内韧性剪切带变形强烈，以压扁作用为主，最大主压应力方向近ＮＥ和Ｓ－Ｎ向，以右旋运动为主。韧性剪切带形成以后，区内主要经历了热蚀变和脆性变形。

An analysis of the rock magnetic fabric can be used to study the fabric characteristics of the rocks and structural deformation. The characteristics of the rock magnetic fabric from ductile shear zones in western Shandong are that the value P and H which symbolize the degree of the magnetic anisotropy are high, the magnetic susceptibility ellipsoid is flattened, the magnetic schistosity is well developed and the magnetic lineation is poor. The analytical results of the magnetic fabric show that the deformation in the ductile shear zones is very strong, of which the flattening deformation is the chief, the orientation of the maximum major stress is nearly NE and S-N, and the movement orientation is to the right. After the formation of ductile shear zones, there is no strong ductile shear deformation in the region, except some thermal alterations and brittle deformation.