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通过对花垣地区铅锌矿床赋矿围岩下寒武统清虚洞组灰岩和热液矿物方解石、闪锌矿的锶同位素研究,探讨了成矿物质来源。测试结果显示,湘西花垣矿田赋矿围岩(清虚洞组灰岩)的87Sr/86Sr值为0.70886~0.70921,与同期海水的锶同位素比值相当,无放射性成因Sr的混入。热液方解石的Sr同位素数据的变化范围为0.70906~0.71022,闪锌矿的Sr同位素数据的变化范围为0.70915~0.71114,(87Sr/86Sr)i值为0.70912~0.70940,高于赋矿围岩清虚洞组灰岩的锶同位素比值,推断成矿流体流经了清虚洞组下伏地层下寒武统石牌组和底寒武统牛蹄塘组,并与其中具有高锶同位素比值的碎屑岩和泥岩等进行了水岩反应及同位素交换。
By studying the strontium isotopes of limestone and hydrothermal mineral calcite and sphalerite of the Lower Cambrian Qingxudong Formation in the ore-bearing rocks of the Huayuan area, the source of ore-forming materials is discussed. The test results show that the 87Sr / 86Sr value of the ore-bearing rock in the Huayuan Ore field (Qingxudong Formation) in western Hunan is 0.70886 ~ 0.70921, which is comparable to the strontium isotope ratio of the seawater in the same period without any radioactive Sr contamination. The Sr isotope data of hydrothermal calcites range from 0.70906 to 0.71022, the Sr isotope data of sphalerite range from 0.70915 to 0.71114, and the (87Sr / 86Sr) i values from 0.70912 to 0.70940, The isotopic ratio of strontium in the limestone of Dongshen Formation suggests that the ore-forming fluids flow through the Lower Cambrian Shipai Formation and the Lower Cambrian Niutitang Formation in the underlying strata of the Qingxudong Formation, and are associated with the crusts with high strontium isotope ratios Rock and mudstone and other rock-water reaction and isotope exchange.