In-situ pyrite trace element and sulfur isotope characteristics and metallogenic implications of the Qixiashan Pb-Zn-Ag polymetallic deposit, Eastern China
In-situ pyrite trace element and sulfur isotope characteristics and metallogenic implications of the Qixiashan Pb-Zn-Ag polymetallic deposit, Eastern China
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华东栖霞山铅锌银多金属矿床原位黄铁矿微量元素和硫同位素特征及成矿意义
DOI：
10.1016/j.oregeorev.2022.104849
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发表时间：
2022-03
影响因子：
3.3
通讯作者：
Miao Yu
中科院分区：
文献类型：
--
作者：
Wen-Dong Zhang;Bin Li;An-Huai Lu;Kui-Dong Zhao;Safiyanu Muhammad Elatikpo;Xiao-Dong Chen;Lei Zhu;Miao Yu
位于长江中下游成矿带的栖霞山铅锌银矿床（Pb + Zn含量为13.4%，Pb + Zn含量为3.9 Kt， Ag含量为236.5 g/t）是中国东部最大的铅锌银多金属矿床。层控矿体赋存于石炭系碳酸盐岩单元中。由于对该矿床的矿质来源和成矿过程缺乏明确的认识，该矿床与其他沉积型矿床是否与晚中生代岩浆活动或石炭系沉积喷发事件有关仍存在争议。栖霞山原矿/同矿黄铁矿s同位素和微量元素数据表明其成因为海水硫酸盐而非岩浆热液。草莓状黄铁矿（Py1）具有较低的Co/Ni比值（<1）、粒径（~ 4 μm）和由细菌硫酸盐还原（BSR）引起的负δ34S值（−27.4 ~−2.2‰），可能是成岩作用。前矿胶状（Py2）和块状（Py3）黄铁矿Mn含量较高，而同矿黄铁矿（Py4和Py5） Pb、Zn和Cu含量较高。前矿/同矿黄铁矿Co/Ni值较低，表明铁和贱金属均为非岩浆成岩成因。流体中硫同位素分馏可能在铅锌银成矿阶段达到平衡。平衡分馏计算表明，δ34S值由Py2向Py5的正移（10.2 ~ + 22.2‰）主要是由热化学硫酸盐还原（TSR）引起的。成矿前黄铁矿可能形成于早石炭世成岩作用，后被表生黄铁矿包裹。合成矿黄铁矿中的铁很可能通过溶解浸出或置换过程从沉积物或矿前黄铁矿中回收。在祁霞山铅锌银成矿过程中，岩浆热液不可能是主要的贱金属来源。
The Qixiashan Pb-Zn-Ag deposit (2.6 Mt at 13.4% Pb + Zn and 3.9 Kt at 236.5 g/t Ag) in the Middle-Lower Yangtze River Valley Metallogenic Belt (MLYRB) is the largest Pb-Zn-Ag polymetallic deposit in Eastern China. The stratabound orebodies are hosted in the Carboniferous carbonate units. Whether this deposit and other sediment-hosted deposits in MLYRB are associated with Late Mesozoic magmatism or Carboniferous sedimentary exhalative events is still disputed, due to the poor constraints on their ore-material source and metallogenic processes. In-situ pre-/syn-ore pyrite S-isotopic and trace-element data from Qixiashan favor a seawater sulfate origin over a magmatic-hydrothermal one. Framboidal pyrite (Py1) is likely diagenetic, as evidenced by its low Co/Ni ratio (<1), size (∼4 μm), and negative δ34S values (−27.4 to −2.2‰) caused by bacterial sulfate reduction (BSR). Pre-ore colloform (Py2) and massive (Py3) pyrites have high Mn concentrations, whereassyn-ore pyrites (Py4 and Py5) have elevated Pb, Zn and Cu grades. The low Co/Ni values of the pre-/syn-ore pyrites indicate that both the Fe and base metals are of non-magmatic diagenetic origin. Sulfur isotope fractionation in the fluid may have reached equilibrium in the Pb-Zn-Ag metallogenic stage. Equilibrium fractionation calculation suggests that the positive shift of δ34S values from Py2 to Py5 (10.2 to + 22.2‰) is primarily caused by thermochemical sulphate reduction (TSR). Pre-ore pyrites were likely formed in early carboniferous diagenesis, and then enclosed by epigenetic pyrites. Iron in thesyn-ore pyrites was most likely recycled from sediments or pre-ore pyrites via dissolution-leaching or replacement processes. During the Qixiashan Pb-Zn-Ag mineralization, the magmatic-hydrothermal fluid is unlikely a major base metal source.
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DOI：
10.1016/j.palaeo.2019.03.010
发表时间：
2019-05
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
D. Rickard
通讯作者：
D. Rickard
影响因子：
4.8
作者：
D. Sangster
通讯作者：
D. Sangster
影响因子：
5
作者：
J. Magnall;S. Gleeson;R. Stern;R. Newton;S. Poulton;S. Paradis
通讯作者：
J. Magnall;S. Gleeson;R. Stern;R. Newton;S. Poulton;S. Paradis
影响因子：
3.9
作者：
R. Large;S. Bull;P. McGoldrick
通讯作者：
R. Large;S. Bull;P. McGoldrick
影响因子：
6.1
作者：
Li Tang;Yu Zhao;Shou‐ting Zhang;Li Sun;Xin-Kai Hu;Yuan‐Ming Sheng;Taorui Zeng
通讯作者：
Li Tang;Yu Zhao;Shou‐ting Zhang;Li Sun;Xin-Kai Hu;Yuan‐Ming Sheng;Taorui Zeng