Abstract Ophicarbonates are found in ophiolite-associated peridotites and bear signature of fluid-rock interaction either on ocean floor or during ophiolite emplacement. The occurrence of ophicarbonate veins hosted by ultramafic rocks of the Indus Ophiolite, Nidar Valley, Ladakh Himalaya, is interpreted within the context of serpentinization of the allochthonous Cretaceous upper mantle section during uplift of the Himalaya orogen. Mixed dolomite-calcite obtained from two veins show carbon isotope ratios consistent with an origin from bicarbonate-dominated fluid and inconsistent with incorporation of atmospheric carbon dioxide in subaerial contact with high pH waters of serpentinization. Strontium isotope ratio of 0.711452–0.712041 are consistent with serpentinization subsequently to emplacement of the ophiolite and by interaction with Cretaceous seawater mixed with continental crust-derived fluid during Neo-Tethys closure. The predominance of lizardite and chrysotile in ophicarbonate veins as documented by Raman spectra also supports a low temperature serpentinization during ophiolite emplacement. The presence of hydrocarbon peaks in fluid inclusions in serpentinized olivine suggests that some of the dissolved inorganic carbon reacted with hydrogen released through oxidation of iron. The ophicarbonates and serpentines in peridotite of Indus ophiolite bear signature of a paleo-environment for Fischer-Tropsch reactions during the last phase of Neo-Tethys closure.

中文翻译：

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含印度河蛇绿岩的蛇绿岩脉的起源：新特提斯闭合期间海水与大陆地壳衍生流体混合的同位素证据

摘要 蛇绿岩伴生橄榄岩中发现了蛇绿岩，并且在海底或蛇绿岩就位期间具有流体-岩石相互作用的特征。在喜马拉雅造山带抬升期间外来白垩纪上地幔部分蛇纹石化的背景下解释了由印度河蛇绿岩、尼达尔河谷、拉达克喜马拉雅山的超镁铁质岩石承载的蛇纹石矿脉。从两条脉中获得的混合白云石-方解石显示出碳同位素比率，这与来自以碳酸氢盐为主的流体的起源一致，并且与大气二氧化碳在与蛇纹石化的高 pH 水的地下接触中的掺入不一致。锶同位素比率为 0.711452-0。712041 与蛇绿岩就位后的蛇纹石化以及在新特提斯闭合期间与混有大陆地壳衍生流体的白垩纪海水的相互作用一致。拉曼光谱所记录的蛇纹石和温石棉在蛇绿岩脉中的优势也支持蛇绿岩就位期间的低温蛇纹石化。蛇纹石化橄榄石中流体包裹体中烃峰的存在表明，一些溶解的无机碳与铁氧化释放的氢发生了反应。印度河蛇绿岩橄榄岩中的氧碳酸盐和蛇纹石具有在新特提斯河闭合的最后阶段进行费-托反应的古环境的特征。拉曼光谱所记录的蛇纹石和温石棉在蛇绿岩脉中的优势也支持蛇绿岩就位期间的低温蛇纹石化。蛇纹石化橄榄石中流体包裹体中烃峰的存在表明，一些溶解的无机碳与铁氧化释放的氢发生了反应。印度河蛇绿岩橄榄岩中的氧碳酸盐和蛇纹石具有在新特提斯河闭合的最后阶段进行费-托反应的古环境的特征。拉曼光谱所记录的蛇纹石和温石棉在蛇绿岩脉中的优势也支持蛇绿岩就位期间的低温蛇纹石化。蛇纹石化橄榄石中流体包裹体中烃峰的存在表明，一些溶解的无机碳与铁氧化释放的氢发生了反应。印度河蛇绿岩橄榄岩中的氧碳酸盐和蛇纹石具有在新特提斯河闭合的最后阶段进行费-托反应的古环境的特征。蛇纹石化橄榄石中流体包裹体中烃峰的存在表明，一些溶解的无机碳与铁氧化释放的氢发生了反应。印度河蛇绿岩橄榄岩中的氧碳酸盐和蛇纹石具有在新特提斯河闭合的最后阶段进行费-托反应的古环境的特征。蛇纹石化橄榄石中流体包裹体中烃峰的存在表明，一些溶解的无机碳与铁氧化释放的氢发生了反应。印度河蛇绿岩橄榄岩中的氧碳酸盐和蛇纹石具有在新特提斯河闭合的最后阶段进行费-托反应的古环境的特征。