Fluids double-fracturing genetic mechanism and mineralization of gold-copper of the breccia pipe at Qibaoshan in Shandong Province

作     者：徐兴旺 蔡新平 秦大军 王杰 梁光河 张小允 刘立金 

作者机构：1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Qibaoshan Gold Corporation Shandong Province 262321 Wuliang China 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2000年第43卷第2期

页      面：113-121页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：ISRP National Natural Science Foundation of China, NSFC, (49802021) Chinese Academy of Sciences, CAS, (k951-A1-404-02-01) 

主　　题：breccia pipe double-fracturing of fluids genetic mechanism mineralization of gold-copper deposit Qi-baoshan. 

摘      要：After studying the characteristics and special texture of the fluidogenous tectonics, mineral assemblage in the cemented vein between breccia and their special distribution, and stress analyzing the joint structures in and around the breccia pipe, it is found that the observed phenomena are caused by a new tectonic dynamic mechanics of fluid——double-fracturing caused bytemperature and pressure of fluids and pulsating expansion. Under the actions of thermal stress and the pressure of fluids, thermal cracks and joints that developed along parts of the thermal cracks formed systematically in the rocks. Under these conditions, up-arching fracture zones that pulsatively expanded upward and cylindrical pressing breccia body were formed. Rocks at the peak of the pyramidal fractures zone break down instantly. Where the difference between pressure of fluids and the overburden pressure exceeded greatly the competence of the rocks, fluid junctions occurred and the velocity of the fluid flow increased as a result. Explosive body expanded upward in the shape of an inverse cone, cone-like explosive breccia body and cover-like shattering breccia body located on the upper part of the breccia pipe were ultimately formed. Gold-rich fluids were enriched and mineralized near the boiling surface in the lower part of the inverse cone-like explosive breccia body where temperature and pressure decreased rapidly, while copper-rich fluids were enriched and mineralized in the junction area where temperature and pressure were relatively high.