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Isotope Tracing and Prospecting Assessment of Gold-Silver Deposits in Zhejiang Province 总被引:1,自引:0,他引:1
Chen Haoshou Xu Butai Department of Earth Sciences Zhejiang University Hangzhou Zhejiang Zhejiang Institute of Geology Mineral Resources Hangzhou Zhejiang Liu Xinzhu 《《地质学报》英文版》1997,71(3):293-304
Three different types of gold and silver deposits in Zhejiang Province(Huangshan gold deposit, Zhilingtou gold-silver deposit and Haoshi silver deposit) showmarked differences in lead and strontium isotopic composition, suggesting three differentsources and geneses of these deposits. The Huangshan gold deposit features low initial Srisotope ratios and low μ values or low content of radiogenic Pb and its ore-forming materialscame primarily from the upper mantle; the Zhilingtou gold-silver deposit shows high initial Srisotope ratios and high μ values or high content of radiogenic Pb and the ore-forming materialswere derived mainly from the upper crust; and the Haoshi silver deposit has its Pb and Srisotope ratios between the above two cases with the ore-forming materials stemming from boththe mantle and the crust. The characteristic Pb isotopic composition may serve as an indicatorfor prospecting for different types of ore deposits. 相似文献
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在浙西北双溪坞群和上墅组火山岩系获得较可靠的Sm-Nd同位素年龄的基础上,本文进一步做了Nd、Sr同位素地球化学研究。∈Nd(T)和∈Sr(T)示踪判别了该区前震旦纪火山岩浆源区特征及其物质来源。同时,Nd同位素模式年龄为该区存在更古老基底提供了重要的地质年代信息。 相似文献
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浙江主要金银(铅、锌)矿床同位素地球化学研究 总被引:2,自引:0,他引:2
应用Rb-Sr等时线法测定了浙江不同类型金、银矿床(璜山金矿、治岭头金银矿、毫石银矿及拔茅、大岭口含银铅锌矿)的成矿时代。不同类型矿床的Sr、Pb同位素组成有显著的差别表明其成矿物质有不同的来源和成因。特征的Pb同位素组成还可以作为不同类型矿床的找矿标志。 相似文献
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In the geochemical study of sedimentation, hydrogen and oxygen isotope data are useful for a discussionon formation conditions and material sources of sediments. Hydrogen and oxygen isotope analyses were madeon clays separated from the sea-floor surface sediments at 9 stations in the western sea region of the AntarcticPeninsula. On the basis of these isotopic data and the clay mineral components and by use of statistical dia-grams, it may be concluded that the clay fraction in this sea region is composed mainly of terrigenous detritus:i.e. it was formed by surface weathering or supergene alteration of the rocks from the terrigenous region in thepeninsular in the presence of meteoric water. However, at least a part of montmorillonite is a marine authigenicmineral formed by alteration of submarine eruptive materials or terrigenous pyroclasts in the presence of seawater. The above result is consistent with the idea derived from the study of clay mineralogy. 相似文献
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据浙江绍兴—龙泉成矿带主要金矿床中的41个铅同位素数据和28个氧、氢同位素数据资料,进行综合分析研究、着重探讨了金矿的物质来源和成矿流体的性质。 相似文献
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浙江中生代晚期火山—沉积岩系层序和时代 总被引:33,自引:7,他引:26
浙江中生代晚期火山—沉积地层由上、下两个岩系组成,上岩系包括横山组、永康群、衢江群及天台群,下岩系包括建德群和磨石山群。这两个岩系的同位素年龄范围分别在110~90Ma和135~120Ma。根据同位素地质年代结合该区火山—沉积地层的古地磁和古生物研究资料,我们提出上岩系的形成时代为早白垩世晚期至晚白垩世早期,下岩系为早白垩世早期 相似文献
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本文报道了浙江省21个中生代火成岩的Nd-Sr同位素组成,其中火山岩的εNd值为-12.6——4.9,ISr值为0.70613-0.71079,tDM年龄为1945-1296Ma;花岗岩类的εNd值为-12.9——5.8,ISr值为0.70533-0.71208,tDM年龄为1900-1230Ma,表明两者具有相似的同位素组成。这种相似性在同一火山-侵入杂岩体中表现更为明显,意味着两者在时、空、源方面具有同一性。与扬子地块的相比,华夏地块的中生代火成岩具有较低的εNd值,较高的ISr值和较古老的Nd模式年龄,这种差异可能主要同这两个区域内基底变质岩在形成时代和成分上的差异有关。通过Sm-Nd同位素组成的对比研究,笔者认为,浙江境内的中生代火成岩可能主要是由基底变质沉积岩衍生的。原始岩浆的形成可能同中、下地壳岩石的熔融有关。 相似文献