开合构造环境下花岗岩体的构造样式与变形差异

Tectonic style and deformation difference of granite bodies in the opening-closing tectonic setting

传统研究认为,大量花岗岩体的侵入发生于区域性伸展环境,是碰撞造山后应力松弛阶段侵位的,称之为造山后或非造山侵入体。近年来,对造山带和古岩浆弧的深入研究发现,花岗岩不但可以侵位于伸展构造环境,也可侵位于挤压构造环境(同构造侵入体),两者在三维空间形态、宏观尺度、露头尺度、显微尺度上的构造样式与变形往往是不同的。区分2类不同构造样式的岩体,对于分析区域构造和造山带演化有着重要的意义。

Previous study maintained that large quantities of granite bodies were intruded in a regional ex-tensional environment.These granite intrusions were emplaced in post-collisional orogenic stress relaxation stage and so are called postorogenic or nonorogenic granite intrusions.In recent years ,in-depth study of orogenic belts and ancient magma arcs shows that granite emplacement may take place not only in an ex-tensional environment but also in a compressional tectonic environment ( syntectonic intrusion ) .However ,the two types of granite intrusions show differences in three-dimensional shape ,macroscopic-scale ,out-crop-scale and microscopic-scale tectonic styles and deformation.