韧性剪切带中的脆性构造及其对金矿化的控制

Two Kinds of Brittle Structures in Ductile Shear Zone and Their Controlling Significances for Gold Mineralization

韧性剪切带是金矿床的最主要赋存体之一，但其中的金矿化主要与脆性断裂有关．将剪切带中脆性构造分为同期和后期２类，详细阐述了其各自成因和特征，并重点探讨了同期脆性构造对金矿化的控制机制，指出同期脆性构造与主剪切带之间的周期性短暂物理化学势差导致成矿流体向前者汇聚，而流体温（Ｔ）。

Ductile shear zone is one of the most importment hosts of gold deposit.Studies show that the gold mineralization occurred in shear zones is mainly related to brittle structures,but little attention has been paid to the reasons.Two kinds of brittle structures within the shear zones, syn and postdeformational, have been divided,and their respective features and genesis have been deciphered. With the attention focused on the controlling mechanism of syndeformational brittle structures during the gold mineralization, we propose that it’s the periodic and transient physical and chemical potential differences between the syndeformational brittle structures and the shear zone leads to the accumulation of oreforming fluids in the syndeformational brittle structures.On the other hand,the decline of temperature (T) and pressure(pf) of oreforming fluids and the seperation of immiscible minor gas species result in the deposition of oreforming materials.