Chromite geochemistry of the Jinchuan Ni-Cu sulfide-bearing ultramafic intrusion (NW China) and its petrogenetic implications
Chromite geochemistry of the Jinchuan Ni-Cu sulfide-bearing ultramafic intrusion (NW China) and its petrogenetic implications
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中国西北金川含镍铜硫化物超镁铁质岩体的铬铁矿地球化学及其成岩意义
DOI：
10.1016/j.oregeorev.2021.104644
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发表时间：
2021-12
影响因子：
3.3
通讯作者：
Ai Qi-Xing
中科院分区：
文献类型：
--
作者：
Kang Jian;Chen Lie-Meng;Yu Song-Yue;Zheng Wen-Qin;Dai Zhi-Hui;Zhou Sheng-Hua;Ai Qi-Xing
铬铁矿作为一种早期分馏相，对镁铁-超镁铁堆晶岩的成因和构造环境具有良好的示踪作用。金川超基性岩体是世界上最大的岩浆型镍铜硫化物矿床之一。尽管对该岩体进行了大量的研究，但对铬铁矿的地球化学特征及其成因意义的认识仍不十分清楚。研究了金川岩体中包裹在橄榄石中的铬铁矿的地球化学特征。铬铁矿颗粒在Fe#（100* Fe 3 +/（Fe 3 ++Al + Cr）= 1.3-47.0）、Cr#（100*Cr/（Cr + Al）= 44.9-92.4）和Mg#（100*Mg/（Mg + Fe 2+）= 4.7-25.7）方面具有大的变化。它们贫Ni（142-1704 ppm）和Co（214-538 ppm），富Ti（3507-66298 ppm），伴有高度可变的Zn（1186-10726 ppm）和Mn（1362-4579 ppm）含量。在MORB标准化模式，铬铁矿颗粒内的最原始的橄榄石的特点是由Ti，V，Zn，Mn和Ni的负异常的正异常，类似于夏威夷拉斑玄武岩和典型的层状侵入。变量之间的主要，次要和微量元素的相关性表明，所有这些元素，除了锌和锰，可能已被多阶段的岩浆过程，很少叠印从岩浆后热液蚀变。铬铁矿中强烈的Ni和Co亏损表明在深度处硫化物液体的优先去除。铬铁矿中Ti的宽范围可能是由于岩浆分异过程中fO 2的变化造成的。而Zn和Mn的含量变化则可能与积云后过程有关。此外，原始铬铁矿的相对高的TiO 2，但低的Al 2 O3的含量与地幔柱相关的堆晶岩。这一特征，再加上铬铁矿的MORB标准化模式，意味着金川岩体类似于典型的拉斑玄武岩层状岩体成因有关的地幔柱。
Chromite, as an early-fractionation phase, has good potential to trace the petrogenesis and tectonic setting of mafic-ultramafic cumulate rocks. The Jinchuan ultramafic intrusion in NW China contains one of the world’s largest magmatic Ni-Cu sulfide deposits. Many studies have been carried out on this intrusion, however, the geochemical features of chromite and its related petrogenetic implications are still poorly constrained. In this study, the geochemistry of chromite enclosed in olivine from the Jinchuan intrusion is investigated. The chromite grains have large variations in Fe# (100*Fe3+/(Fe3++Al + Cr) = 1.3–47.0), Cr# (100*Cr/(Cr + Al) = 44.9–92.4), and Mg# (100*Mg/(Mg + Fe2+) = 4.7–25.7). They are depleted in Ni (142–1704 ppm) and Co (214–538 ppm) and enriched in Ti (3507–66298 ppm), accompanied by highly variable contents of Zn (1186–10726 ppm) and Mn (1362–4579 ppm). In the MORB-normalized patterns, chromite grains within the most primitive olivine are characterized by positive anomalies of Ti, V, Zn, and Mn and negative anomalies of Ni, similar to those in the Hawaiian tholeiitic basalts and typical layered intrusions. Variable correlations among the major, minor, and trace elements indicate that all these elements, except for Zn and Mn, may have been governed by multistage magmatic processes with little overprint from postmagmatic hydrothermal alteration. The strong Ni and Co depletions in chromite indicate prior removal of sulfide liquids at depth. The wide range of Ti in chromite may have been caused by thefO2change during magma fractionation. The variable contents of Zn and Mn, by contrast, may be related to postcumulus processes. Furthermore, the relatively high TiO2but low Al2O3contents of the primitive chromite are comparable with those of mantle plume-related cumulate rocks. This feature, coupled with the MORB-normalized patterns in chromite, implies that the Jinchuan intrusion is similar to typical tholeiitic layered intrusions genetically related to a mantle plume.
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影响因子：
5.8
作者：
J. Lehmann;N. Arndt;B. Windley;Mei‐Fu Zhou;C. Wang;C. Harris
通讯作者：
J. Lehmann;N. Arndt;B. Windley;Mei‐Fu Zhou;C. Wang;C. Harris
影响因子：
3.9
作者：
P. Roeder;I. Campbell
通讯作者：
P. Roeder;I. Campbell
西南冷水青岩浆硫化物矿床岩石成因及成矿作用：亲铜元素（PGE、Se）和Sr-Nd-Os-S同位素的制约
DOI：
10.5382/econgeo.2018.4566
发表时间：
2018-05
期刊：
Economic Geology and the Bulletin of the Society of Economic Geologists
影响因子：
--
作者：
Yao Jun-Hua;Zhu Wei-Guang;Li Chusi;Zhong Hong;Bai Zhong-Jie;Ripley Edward M.;Li Chao
通讯作者：
Li Chao
新疆准噶尔地体北部泥盆纪岛弧的苦味岩和相关熔岩的地球化学：对岩石成因、弧地幔来源和构造环境的影响
影响因子：
3.5
作者：
张招崇
通讯作者：
张招崇
影响因子：
3.9
作者：
G. Chai;A. J. Naldrett
通讯作者：
G. Chai;A. J. Naldrett