World-class Xincheng gold deposit: An example from the giant Jiaodong gold province
World-class Xincheng gold deposit: An example from the giant Jiaodong gold province
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世界级新城金矿：以胶东金矿大省为例
DOI：
10.1016/j.gsf.2015.08.006
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发表时间：
2016-05
影响因子：
8.9
通讯作者：
Wang XD
中科院分区：
文献类型：
--
作者：
Yang LQ;Deng J;Guo RP;Guo LN;Wang ZL;Chen BH;Wang XD
胶东金矿床是我国目前最重要的金资源（Au储量>4000 t），也是全球最大的产金国（2013年Au产量达428 t）。胶东也被认为可能是地球上唯一一个世界级的巨型金矿聚集地，那里有相对年轻的金矿石（约1000年）。130-120 Ma）沉积在年龄为2 Ga的岩石中。新城高品位金存款是胶东半岛黄金大省中最大的金矿床之一，已探明金储量200 t以上。它位于胶北盆地的西北部，由约1000个盆地组成。132-123 Ma新城石英二长岩和二长花岗岩。矿化带受北东向、北西向焦家断裂及次级断裂控制，主要局限于断裂下盘。主要的浸染状和网脉状矿石与强烈的绢云母化、硅化、硫化和钾长石化以及少量的碳酸盐围岩蚀变晕有关。四个成矿阶段分别为黄铁矿-石英-绢云母（第一阶段）、石英-黄铁矿（第二阶段）、石英-多硫化物（第三阶段）和石英-碳酸盐（第四阶段）。金主要以银金矿的形式出现，少量的硫化物型自然金和稀有的自然银和辉银矿，通常与黄铁矿、黄铜矿、方铅矿和闪锌矿伴生：后者已探明的资源量约为105吨银、713吨铜和5100吨硫。1型水碳酸盐（H2O-CO2）、2型水（液态H2O +气态H2O）和3型CO2（液态CO2和气态CO2）包裹体。1型包裹体的均质温度范围为221 - 304 °C，盐度为2.4-13.3 wt.% NaCl当量，堆密度为0.858-1.022 g/cm 3。热液硫化物的δ 34 SCDT值为4.3-10.6‰，热液石英的δ 18 O值中值为13.0‰，热液石英中流体包裹体的δD值中值为−75‰。计算得到的δ 18 O水的中值为5.2‰。新城金存款成矿时代小于123 ± 1 Ma，可能在120.9 ~ 119.9 Ma之间。新城金存款矿物系统成因模式表明，成矿流体为中温、富CO2、低盐度的H2O-CO2深源变质成矿流体，与俯冲的古太平洋岩石圈脱水脱碳作用有关。焦家断裂在脆-韧性转换阶段制约了成矿流体和金属的运移。幕式压力下降引起的流体不渗透性，导致新城巨型金存款中有显著的高品位金沉积。
The Jiaodong gold deposits are currently the most important gold resources (with Au reserves of >4000 t) in China, and the leading gold-producing country globally (with Au production of ∼428 t in 2013). Jiaodong is also considered as perhaps the only world-class to giant gold accumulation on the planet where relatively young gold ores (ca. 130–120 Ma) were deposited in rocks that are 2 Ga older. The Xincheng world-class high-grade gold deposit, with a proven reserve of >200 t gold, is one of the largest deposits in the giant gold province of the Jiaodong Peninsula. It is located in the northwestern part of the Jiaobei Uplift, and hosted by ca. 132–123 Ma Xincheng quartz monzonites and monzogranites. Ore zones are structurally controlled by the NE-trending and NW-dipping Jiaojia Fault and subsidiary faults, and are mainly restricted to the footwall of the fault. The dominant disseminated- and stockwork-style ores are associated with strong sericitization, silicification, sulfidation and K-feldspathization, and minor carbonate wallrock alteration halos. The four mineralization stages are pyrite–quartz–sericite (stage 1), quartz–pyrite (stage 2), quartz–polysulfide (stage 3) and quartz–carbonate (stage 4). Gold occurs dominantly as electrum, with lesser amounts of sulfide-hosted native gold and rare native silver and argentite, normally associated with pyrite, chalcopyrite, galena and sphalerite: the latter with proven resources of about 105 t Ag, 713 t Cu, and 5100 t S.There are three types of ore-related fluid inclusions: type 1 aqueous-carbonate (H2O–CO2), type 2 aqueous (liquid H2O + vapor H2O), and type 3 CO2(liquid CO2and vapor CO2) inclusions. Homogenization temperatures range from 221 to 304 °C for type 1 inclusions, with salinities of 2.4–13.3 wt.% NaCl eq., and bulk densities of 0.858–1.022 g/cm3. Theδ34SCDTvalues of hydrothermal sulfides are 4.3–10.6‰ andδ18O values of hydrothermal quartz have a median value of 13.0‰.δD values of fluid inclusions in hydrothermal quartz have a median value of −75‰. Calculatedδ18Owaterhas a median value of 5.2‰. The timing of gold mineralization at the Xincheng gold deposit is younger than 123 ± 1 Ma, and likely between 120.9 and 119.9 Ma.A minerals system genetic model for the probable epizonal orogenic Xincheng deposit suggests an initial medium temperature, CO2-rich, and low salinity H2O–CO2deeply sourced metamorphic ore fluid associated with dehydration and decarbonization of subducting Paleo-Pacific lithosphere. The Jiaojia Fault constrained the migration of ore-forming fluids and metals at the brittle–ductile transition. Fluid immiscibility, caused by episodic pressure drops, led to significant high-grade gold deposition in the giant Xincheng gold deposit.
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影响因子：
1.8
作者：
Yang Li
通讯作者：
Yang Li
DOI：
10.1086/378486
发表时间：
2003-11
期刊：
The Journal of Geology
影响因子：
--
作者：
Jian-wei Li;P. Vasconcelos;Jun Zhang;Mei‐Fu Zhou;Xiaojun Zhang;Feng-Hua Yang
通讯作者：
Jian-wei Li;P. Vasconcelos;Jun Zhang;Mei‐Fu Zhou;Xiaojun Zhang;Feng-Hua Yang
胶东半岛幔源流体与金矿成矿的关系——来自D−O−C−S同位素系统学的证据
影响因子：
3.3
作者：
通讯作者：
--
DOI：
10.1111/j.1755-6724.2000.tb00025.x
发表时间：
2000-09
期刊：
Acta Geologica Sinica ‐ English Edition
影响因子：
--
作者：
Yang Dejiang
通讯作者：
Yang Dejiang
成矿与克拉通破坏：华北克拉通的记录
影响因子：
3.3
作者：
Sheng-Rong Li, M. Santosh
通讯作者：
Sheng-Rong Li, M. Santosh