Genesis of two different types of gold mineralization in the Linglong gold field, China: Constrains from geology, fluid inclusions and stable isotope
Genesis of two different types of gold mineralization in the Linglong gold field, China: Constrains from geology, fluid inclusions and stable isotope
复制标题
中国玲珑金田两种不同类型金矿化的成因：地质、流体包裹体和稳定同位素的制约
DOI：
10.1016/j.oregeorev.2014.03.018
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发表时间：
2015-03
影响因子：
3.3
通讯作者：
Kui-Feng Yang
中科院分区：
文献类型：
--
作者：
M Santosh;Fang-Fang Hu;F Pirajno;Kui-Feng Yang
东风、玲珑金矿床位于华北胶东半岛西北部。矿床主要产于中生代花岗岩类中，构造上受招远-平度断裂带控制。东风金矿化以浸染状矿石和硫化物网脉形式产出，通常被广泛的蚀变边缘所包裹。与此相反，玲珑矿化的特点是块状含金石英脉，蚀变晕狭窄。两个矿床均经历了3个成矿阶段，早期以石英±黄铁矿为代表，中期以金+石英+黄铁矿或金+石英+贱金属硫化物为代表，晚期以石英+碳酸盐±黄铁矿为代表。根据岩相学、显微测温和激光拉曼光谱等特征，将该矿床流体包裹体分为四类：（1）纯CO2流体包裹体（I型）;（2）H2O-CO2-NaCl流体包裹体（II型）;（3）H2O-NaCl流体包裹体（4）含子矿物或多相流体包裹体（IV型）。在东风金存款中，早、中期石英主要为原生II型流体包裹体，在276-341 °C温度下完全均一化，盐度为2.8- 11.7wt.% NaCl当量，温度为248-310 °C，盐度为3.3-10.8重量% NaCl当量。早期石英中可观察到少量原生I型流体包裹体。晚期石英仅含III型流体包裹体，均一温度117-219 ℃，盐度0.5- 8.5wt.% NaCl当量。中期流体压力为226-338 MPa，表明金成矿作用主要发生在8.4- 12.5km的古深处。玲珑金存款早期石英中主要含有原生的II型流体包裹体和少量的I型流体包裹体，其中II型流体包裹体的盐度为3.3- 7.5wt.% NaCl当量和271-374 °C的均质化温度。中期石英主要含有四种类型的流体包裹体，其中II型流体包裹体均一温度为251-287 ℃，盐度为5.5- 10.3wt.% III型包裹体均一温度为244-291 ℃，盐度为4.1- 13.3wt.% NaCl当量。晚期石英中的流体包裹体为Ⅲ型，盐度较低，为0.3- 8.2wt.% NaCl当量和103-215 °C的低均质化温度。中期流体的捕集压力为228-326 MPa，表明金矿化主要发生在8.4-12.1 km的古深处。金的沉淀可能是由于次级断裂开放空间内的压力和温度波动引起的H_2 O-CO_2-NaCl流体的相分离或沸腾作用的结果，东风矿床和玲珑矿床的黄铁矿δ ~（34）S值相似，分别为5.8 - 7.0‰和5.9 - 7.4‰。东风存款和玲珑存款石英氧、氢稳定同位素分析结果分别为δ 18 O =-3.8 ~+6.4 ‰和δ D =-90.5 ~-82.7 ‰;稳定同位素数据表明，两个金矿床的成矿流体均为岩浆成因，成矿过程中或成矿后，浅层大气降水逐渐渗入。
The Dongfeng and Linglong gold deposits are located in the northwest Jiaodong Peninsula, North China Craton. The deposits are mainly hosted in the Mesozoic granitoids and structurally controlled by the Zhaoyuan–Pingdu fault zone. Gold mineralization at Dongfeng occurs as disseminated ores and sulfide stockworks, typically enveloped by broad alteration selvages. In contrast, mineralization at Linglong is characterized by massive auriferous quartz veins with narrow alteration halos. Three stages of mineralization were identified in both deposits, with the early stage represented by quartz ± pyrite, the middle stage by gold + quartz + pyrite or gold + quartz + base metal sulfides, and the late stage by quartz + carbonate ± pyrite, respectively. Four types of fluid inclusions were distinguished based on petrography, microthermometry, and laser Raman spectroscopy, including (1) pure CO2fluid inclusions (type I), (2) H2O–CO2–NaCl fluid inclusions (type II), (3) H2O–NaCl fluid inclusions (type III), and (4) daughter mineral-bearing or multiphase fluid inclusions (type IV).In the Dongfeng gold deposit, the early- and middle-stage quartz mainly contains primary type II fluid inclusions that completely homogenized at temperatures of 276–341 °C with salinities of 2.8–11.7 wt.% NaCl equivalent, and temperatures of 248–310 °C with salinities of 3.3–10.8 wt.% NaCl equivalent, respectively. A few primary type I fluid inclusions could be observed in the early-stage quartz. In contrast, the late-stage quartz contains only the type III fluid inclusions with homogenization temperatures of 117–219 °C, and salinities of 0.5–8.5 wt.% NaCl equivalent. The estimated pressures for the middle-stage fluids are 226–338 MPa, suggesting that gold mineralization mainly occurred at paleodepths of deeper than 8.4–12.5 km. The mineralization resulted from extensive water–rock interaction between the H2O–CO2–NaCl fluids and wallrocks in the first-order fault.In the Linglong gold deposit, the early-stage quartz mainly contains primary type II fluid inclusions and a few type I fluid inclusions, of which type II fluid inclusions have salinities of 3.3–7.5 wt.% NaCl equivalent and homogenization temperatures of 271–374 °C. The middle-stage quartz mainly contains all four types of fluid inclusions, among which the type II fluid inclusions yield homogenization temperatures of 251–287 °C and salinities of 5.5–10.3 wt.% NaCl equivalent, while the type III fluid inclusions have homogenization temperatures of 244–291 °C and salinities of 4.1–13.3 wt.% NaCl equivalent. Fluid inclusions in the late-stage quartz are type III fluid inclusions with low salinities of 0.3–8.2 wt.% NaCl equivalent and low homogenization temperatures of 103–215 °C. The trapping pressure estimated for the middle-stage fluids is 228–326 MPa, suggesting that the gold mineralization mainly occurred at paleodepths of about 8.4–12.1 km. Precipitation of gold is possibly a consequence of phase separation or boiling of the H2O–CO2–NaCl fluids in response to pressure and temperature fluctuations in the open space of the secondary faults.The δ34S values of pyrite are similar for the Dongfeng and Linglong deposits and show a range of 5.8 to 7.0‰ and 5.9 to 7.4‰, respectively. Oxygen and hydrogen stable isotopic analyses for quartz yielded the following results: δ18O = − 3.8 to + 6.4‰ and δD = − 90.5 to − 82.7‰ for the Dongfeng deposit, and δ18O = 0.0 to + 8.9‰ and δD = − 77.4 to − 63.7‰ for the Linglong deposit. Stable isotope data show that the ore-forming fluids of the two gold deposits are of magmatic origin, with gradual incorporation of shallower meteoric water during/after mineralization.
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影响因子：
3.9
作者：
Jin-Hui Yang;Sun‐Lin Chung;S. Wilde;Fu-Yuan Wu;M. Chu;C. Lo;H. Fan
通讯作者：
Jin-Hui Yang;Sun‐Lin Chung;S. Wilde;Fu-Yuan Wu;M. Chu;C. Lo;H. Fan
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：
--
影响因子：
5.8
作者：
Yiefei Jia;X. Li;R. Kerrich
通讯作者：
Yiefei Jia;X. Li;R. Kerrich
影响因子：
5.8
作者：
A. Draut;P. Clift
通讯作者：
A. Draut;P. Clift