夹皮沟剪切带中金矿脉形成化学动力学

夹皮为剪切带中存在着两种类型金矿化：（１）片糜岩型金矿化，（２）黄铁矿石英脉型金矿化（脉）。在韧性剪切阶段，围压较大，△Ｖｒ＜０，不能产生流体压力，也不能形成金矿化；随着剪切带演化，围压降低，产生了流体压力大于围压，即面△Ｖｒ＞０，产生了流体压力裂隙，并有矿化作用形成。矿化早期形成片糜岩型金矿化主要由流体压力裂隙所控制，而黄铁矿石英脉型金矿化则是由流体压力及岩石应力性质所决定。由片糜岩型金矿化转化为黄铁矿石英脉型金矿化是一个漫长地质时期，但由流体产生的成矿裂隙时间较短，大约为４０～８０ａ。

CHEMICAL KINETIC OF GOLD VEINS IN THE SHEAR ZONE AT THE JIA PIGOU

There are two types of gold mineralizations in Jia Pigou Shear zone, (1)foliated mylonite type and (2) pyrite-quartz vein type. During ductile shearing action, the compress is high (ΔVr<0) and the mineralization didn''t occur. With the development of the zone, when ΔVr>0,gold minerals precipitated. Hydrofracturing controlled early mineralhaiton in foliated mylonite.Both of hydrofracturing and strain of rocks controlled the pyrite quartz veins. The fracture was formed by fluid in a short interval of 4-8 years calculated by kinetics.