英语翻译Formation of Sedimentary Rock-Hosted Stratiform Copper D

英语翻译
Formation of Sedimentary Rock-Hosted Stratiform Copper Deposits
through Earth History
Society of Economic Geologists,Inc.Economic Geology.2010
Abstract
Sedimentary rock-hosted stratiform copper deposits form by movement of oxidized,copper-bearing fluids across a reduction front that results in the precipitation of copper sulfides.Large-scale production of such oxidized fluids,as well as the formation of mobile hydrocarbons (oil) has probably been common since the formation of the first red beds in the Paleoproterozoic,and deposits of this type occur in rocks from the Paleoproterozoic to the Tertiary.However,supergiant deposits are currently recognized in only three basins:the Paleoproterozoic Kodaro-Udokan basin of Siberia,the Neoproterozoic Katangan basin of south-central Africa,and the Permian Zechstein basin of northern Europe.The paucity of data regarding the Udokan deposit makes understanding this system difficult in terms of Earth history events.Both the Neoproterozoic and the Permian were times of supercontinent breakup with major landmasses at low latitudes.This global tectonic framework favored the formation of failed rifts that subsequently became significant intracratonic basins with basal,synrift red-bed sequences overlain by marine and/or lacustrine sediments and,in some basins located at low latitudes,by thick evaporitic strata.The intracratonic setting of these basins allowed the development of a hydrologically closed basinal architecture in which highly oxidized and saline,moderate-temperature basinal brines were produced that were capable of supplying reduction-controlled sulfide precipitation over very long time periods (tens to hundreds of millions of years).The length of time available for the mineralizing process may be the key factor necessary to form supergiant deposits.However,examination of the absolute ages for the Kupferschiefer (Zechstein basin) and Katangan deposits allows speculation that other factors may also have been important.Both the Neoproterozoic and Permian were times of major glacial events.Glaciation may also be conducive for the formation of supergiant sediment-hosted stratiform copper deposits.Glacial periods correspond to magnesium- and sulfate-rich oceans that could have been responsible for additional sulfur in basinal brines developed during evaporite formation and would then be available during the long mineralization process.

长久时间铜矿石岩层通过沉积形成
社会经济地理学家Inc.Economic Geology.2101年文摘
铜矿石岩层沉积的形式是通过被氧化,含铜流体的运动,导致硫化铜进行化学沉淀.大规模生产这种被氧化的液体与非固体的烃类化合物（石油）的形成很有可能是相同的自从在古代第一个红层的矿床的形成,并且尽管在岩石中的这种类型是从古代到第三纪.然而,目前公认的超巨星沉积物在仅有的三大盆地中,分别是在古元古代西伯利亚的 Kodaro-Udokan盆地,在新元古代非洲的加丹加南部和中部盆地和欧洲北部二叠纪的蔡希斯坦统Z盆地.缺乏有关的数据,乌多坎的沉淀物不能适应这种形式在长期的历史形成中.无论是新元古代和二叠纪都是超极大陆式分离在低纬度地区主要的陆地.这种全球的构造结构帮助没能裂缝的形成,导致后来成为重要的古代大陆盆地的基底.同生裂谷红层矿床的序列排在海洋和湖泊的沉积物之上位于低纬度地区通过厚厚的蒸发岩层.古代大陆上的这些盆地环境允许地质接近盆地的发展.高浓度氧和盐溶液.其中高度氧化和盐溶液中温盆地卤水制作了被供应在很长的时间内减少控制硫化沉淀（数十至数百万元的能力发展导致）.这么长的时间的矿形成过程中可能是关键因素,可能是要形成超大型沉淀物.然而,绝对的年龄的考验对于Kupferschiefer（蔡希斯坦统盆地）和加丹加省（扎伊尔沙巴区）的沉淀物可能还有其他因素也可能很重要.无论是新元古代,二叠纪时期对于主要的冰川时期是成倍的.冰川作用也可能是有益的对于超大铜矿石岩层的沉积物的形成.冰川时期一致的对于镁和硫酸盐丰富的海洋可能有责任的对于额外的硫化物在盆地形成的过程中,在蒸发岩形成过程中和长期矿化过程中是可利用的.