• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Ofioliti >Minerals Of Au, Ag And U In Volcanic-rock-associated Massive Sulfide Deposits Of The Northern Apennine Ophiolite, Italy
【24h】

Minerals Of Au, Ag And U In Volcanic-rock-associated Massive Sulfide Deposits Of The Northern Apennine Ophiolite, Italy

机译：意大利北部亚平宁蛇绿岩与火山岩相关的块状硫化物矿床中的金，银和铀矿物

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Ore samples from five copper sulfide deposits associated with Jurassic ophiolites in the Northern Apennine belt of Italy were found to contain gold, acanthite or argentite (Ag2S), and freibergite (Ag,Cu,Fe)12(Sb,As)4S13. These precious-metal minerals are part of a complex assemblage of microscopic to submicroscopic (<10 mm) accessory phases, including uraninite, barite, galena, smithsonite, siderite, a La-Ce carbonate and a Sn hydroxide, attributable to the rare mineral hydroromarchite Sn3O2(OH)2. The textures of the sulfide host are indicative of metal deposition in a range of conditions, involving initial precipitation from hot, metal-charged solutions (syngenesis), followed by post-depositional replacement of biological material and resedi-mentation of clasts, at low temperature (epigenesis). Syn-genetic gold is Ag-rich and associated with uraninite in Fe-Cu-rich ore. The fineness of native gold increases byrnloss of Ag into secondary Ag2S during seafloor weathering of the sulfides. Freibergite forms during recrystallization of sphalerite in massive Zn-Fe ore. Hydroromarchite occurs in massive Zn-Fe ore, closely related with late deposition of siderite and secondary pyrite, possibly due to the action of neutral to basic and reducing waters flushing through the ore in the initial stages of seafloor diagenesis. The widespread evidence for seafloor resedimentation and for bio-genic-activity-driven reworking of the sulfides suggests a transition from proximal VMS to a more distal type of deposit formed by resedimentation processes in a dynamic tectonic environment. This scenario seems to be consistent with the interpretation of the Jurassic Ligurian ocean as a narrow basin in the early stage of its opening, having its modern analogue in the Red Sea.
机译：在意大利北部亚平宁带的五个侏罗纪蛇绿岩伴生的硫化铜矿中发现的矿石样品中含有金，钙长石或闪锌矿（Ag2S）和方铁矿（Ag，Cu，Fe）12（Sb，As）4S13。这些贵金属矿物是微观到亚微观（<10 mm）辅助相的复杂组合的一部分，这些相包括铀矿，重晶石，方铅矿，铁橄榄石，菱铁矿，La-Ce碳酸盐和Sn氢氧化物，这归因于稀有矿物水铬铁矿Sn 3 O 2（OH）2。硫化物基质的织构表明在一定条件下金属的沉积，包括从热的，金属带电的溶液中初始沉淀（同质作用），然后在低温下沉积后置换生物材料并重沉积碎片。 （表观遗传）。同生金富含银，并与富铁铜矿石中的铀矿有关。在硫化物的海底风化过程中，天然金的细度增加了银向次生Ag2S中的损耗。在块状Zn-Fe矿中闪锌矿的重结晶过程中会形成贝氏体。块状锌铁矿石中存在水铬铁矿，这与菱铁矿和次生黄铁矿的后期沉积密切相关，这可能是由于在海床成岩初期，中性到碱性的作用和减少了冲刷矿石中的水的作用。海底再沉积和生物活性驱动的硫化物再加工的广泛证据表明，在动态构造环境中，从近端VMS过渡到了再沉积过程形成的更远端类型的沉积物。这种情况似乎与在开放初期将侏罗纪利古里亚海解释为狭窄的盆地相一致，其现代类似物在红海中。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号