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此滑石矿床赋存于震旦系中统上岩组镁质碳酸盐岩中,受向斜构造控制。矿体分布在向斜构造两翼;滑石在白云石大理岩、菱镁岩和二云母石英片岩的接触带中,呈透镜状产出,含有较多的白云石大理岩、菱镁岩残留体。滑石矿体的矿物成份以滑石为主,另有蛇纹石、透闪石及少量绿泥石和有机质,没有方解石。滑石矿体的形成是由于变质热液交代白云石大理岩、菱镁岩而成。其形成过程是:区域变质作用过程中产生的大量变质热液在碱性介质条件下溶解石英片岩,生成可溶性的偏硅酸,同时沿着向斜构造两翼不断汇集。当温度、压力或PH值降低时,偏硅酸脱水析出SiO_2,此时若遇到白云石大理岩、菱镁岩即发生交代作用而生成滑石矿。甘肃省金塔县四道红山—天仓一带分布有多处滑石矿点。目前已在四道红山探明一个中型滑石矿床,并已开采。
This talc deposit occurs in magmatic carbonate rocks of Sinian Upper Cretaceous and is controlled by synclinal structure. The ore bodies are distributed in syncline structures. Talc is lenticular in the contact zone of dolomite marble, magnesite and ductile quartz schist, and contains more dolomite marble and magnesite remains. Talc ore mineral composition of talc-based, another serpentine, tremolite and a small amount of chlorite and organic matter, no calcite. The formation of talc ore body is due metamorphism hydrothermal metamorphic dolomite marble, magnesite from. The formation process is: a large number of metamorphic hydrothermal fluids produced during the regional metamorphism dissolve quartz schist under alkaline conditions to produce soluble metasilicic acid, while the two wings are continuously converged along the syncline. When the temperature, pressure or PH value decreases, the metasilicic acid dehydrates and precipitates SiO_2. At this time, if dolomite marble is encountered, the magnesite will occur to produce talcum. There are several places of talc deposits in the four red mountains in Tianzhu County, Guta Province. At present, a medium-sized talc deposit has been identified at Si Da Hong Shan and has been mined.