柞水大西沟菱铁矿床地质特征及成因探讨

山阳－柞水矿集区位于商丹断裂和山阳－凤镇断裂之间，区域上归属于中秦岭褶皱带，出露地层属海相粘土质碎屑岩—碳酸盐岩含铁建造，整个岩石受区域变质作用影响，形成浅变质的绿泥石岩相带。断裂构造和岩浆活动强烈，成矿条件优越，是重要的多金属矿集区。柞水大西沟大型菱铁矿、重晶石多金属矿床位于秦岭褶皱系礼县—柞水华力西褶皱带中东段，西芦山—蔡玉窑复向斜西端，交公庙向斜的南翼。以菱铁矿为主的矿体赋存于泥质碎屑岩建造向碳酸盐岩建造过渡的部位。成矿物质主要来源于古海槽底的断裂带的热卤水，部分成矿物质可能来源于火山—次火山。这些成矿物质在海盆中富集、沉积成矿，其后的变质作用使部分菱铁矿变成磁铁矿，有叠加、富集作用。矿床成因主要为热卤水沉积成矿。

Geological characteristics and genesis of the Daxigou siderite deposit in Zhashui, Shanxi Province

The Shanyang-Zhashui ore concentration area is located between the Shangdan and the Shanyang-Fengzhen faults, and belongs to the Middle Qinling fold zone in regional tectonics. This area has experienced strong faulting and magmatic activities, hosting good metallogenic conditions, thus Becoming an important polymetallic ore accumulation area. The Daxigou, Zhashui large-scale siderite and barite polymetallic deposit is located in the central-eastern Lixian-Zhashui fold belt of Varisan of the Qinling fold system, the west end of the Xilushan-Caiyuyao syncline and the south limb of the Jiaogongmiao syncline. The ore bodies dominated by siderite occur in the transition from clastic rock formation to carbonate formation. The metallogenic material mainly came from the hot brine of the fault zone at the bottom of an ancient trough, and some might come from volcano-subvolcano. These metallogenic materials were enriched and deposited in the ocean basin, and subsequent metamorphism turned some siderite into magnetite with superposition and enrichment. The genesis of the deposit is primarily the mineralization of hot brine sediments.