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吕梁山北段变质岩系中，变形分解现象从宏观到微观的各级尺度上均有表现。平面上强弱变形带（域）常呈网结状形态产出，剖面上随深度的加深，强弱变形带（域）互为消长。在变形分解作用下，角闪石转化为黑云母、绿泥石，斜长石牌号降低。固流限较低的矿物发生溶解，或充填张裂隙形成同构造分泌结晶脉，或在一定条件下形成变斑晶，致使岩石的结构构造由块状向片麻状、片状转化。Ｍｇ、Ｆｅ、Ｔｉ、Ｐ、Ｋ、Ｒｂ增高，Ｓｉ、Ｎａ、Ｓｒ降低，这些变化与同源岩浆演化规律相反。据此推论太古界眼球状片麻岩很可能存在灰色片麻岩变形分解作用的成因类型。
Lvliangshan northern metamorphic rock series, the deformation decomposition phenomenon from the macro to the micro-scale at all levels have shown. In the plane, the strong and weak deformation zones (domains) often appear in the form of net-like nodes. As the depth deepens in the section, the strong and weak deformation zones (domains) increase and decrease each other. In the role of deformation and decomposition, amphibole into biotite, chlorite, plagioclase grades lower. The mineral with lower solid flow limit dissolves, or fills the cracks with the same structure to form the crystal vein, or forms the speckled crystal under certain conditions. As a result, the structural structure of rock changes from massive to gnarled and flaky. The contents of Mg, Fe, Ti, P, K and Rb increased while the contents of Si, Na and Sr decreased. These changes were contrary to the evolution of the same source rocks. Therefore, it is concluded that the genetic type of gneiss in the Archean world is likely to have the deformation and decomposition of gray gneiss.