琼西戈枕断裂带多因复成金矿成矿特征

METALLOGENIC CHARACTERISTICS OF POLYGENETIC GOLD DEPOSITS IN THE GEZHEN FAULT ZONE OF WESTERN HAINAN ISLAND

海南岛西部的戈枕断裂带处于东南地洼区儋县地穹的西南缘。由于该区地壳经历了前地槽、地槽、地台、地洼等四个发展阶段，致使该区经受区域变质、混合岩化、岩浆侵入和动力变质等多种地质作用，为戈枕断裂带多阶段成矿创造了良好的地质构造条件，并使受戈枕断裂控制的金矿床在矿体形态、产状、矿化特点、围岩蚀变、矿石类型、成矿阶段、金矿成矿物质来源、成矿的地质、地球化学特征等许多方面，具有多因复成金矿成矿特点。构造控金模拟实验结果为戈枕断裂带构造变形及构造作用使金活化迁移、富集提供实验依据。

The Gezhen fault zone in the Western Hainan Island lies in the Southwestern fringe ofChanxian geodome of the southeastern geodepression region. The curst of this area underwent four development stages, previous stage of platformal trough, platformal trough, platform and geodepression, led to various geological processes occuring in this area, such asnormal metamorphism, migmatitization, ignous intrusion, dynamic metamorphism etc. Allthese brought advantageous conditions of geotectonics to the multistage mineralization ofGezhen fault zone, which made the gold deposits controlled by the Gezhen fault zone embodymetallogenic characteristics of polygenetic gold deposits in the aspects of morphology of orebody, occurrence of ore body, mineralization characteristics, wallrock alteration, stages ofmineralization, material source of gold mineralization and geochemical characteristics of oreforming. processes etc.. The simulated laboratory test of tectonic-controlled gold providesexperimental evidences for the fact that the structural deformation and the structural processof the Gezhen fault zone led to the remobilization and concentration of gold.