TY - JOUR TI - Sulfur isotopic compositions of sulfides along the Southwest Indian Ridge: implications for mineralization in ultramafic rocks AU - Dias, Ágata AU - Ding, Teng AU - Tao, Chunhui AU - Liang, Jin AU - Chen, Jie AU - Wu, Bin AU - Ma, Dongsheng AU - Zhang, Rongqing AU - Wang, Jia AU - Liao, Shili AU - Wang, Yuan AU - Yang, Weifang AU - Liu, Jia AU - Li, Wei AU - Zhang, Guoyin AU - Huang, Hui T2 - Mineralium Deposita DA - 2020/10/31/ PY - 2020 DO - 10.1007/s00126-020-01025-0 DP - DOI.org (Crossref) J2 - Miner Deposita LA - en SN - 0026-4598, 1432-1866 ST - Sulfur isotopic compositions of sulfides along the Southwest Indian Ridge UR - http://link.springer.com/10.1007/s00126-020-01025-0 Y2 - 2021/03/30/07:28:44 ER - TY - JOUR TI - Trace-element compositions of sulfides from inactive Tianzuo hydrothermal field, Southwest Indian Ridge: Implications for ultramafic rocks hosting mineralization AU - Ding, Teng AU - Wang, Jia AU - Tao, Chunhui AU - Dias, Ágata Alveirinho AU - Liang, Jin AU - Wang, Yuan AU - Chen, Jie AU - Wu, Bin AU - Huang, Hui T2 - Ore Geology Reviews AB - The recently explored inactive Tianzuo hydrothermal field, in the amagmatic segment of the ultraslow-spreading Southwest Indian Ridge (SWIR), is closely associated with detachment faults. In this site, sulfide minerals are hosted by serpentine-bearing ultramafic rocks and include high-temperature (isocubanite, sphalerite, and minor pyrrhotite) and low-temperature (pyrite I, marcasite, pyrite II, and covellite) phases. In this study, trace-element concentrations of isocubanite and pyrite II were used to elucidate mineralization processes in ultramafic rocks hosting sulfides. Results show that isocubanite is enriched in metals such as Cu, Co, Sn, Te, Zn, Se, Pb, Bi, Cd, Ag, In, and Mn, and pyrite II is enriched in Mo and Tl. The marked enrichment in Te, Cu, Co, and In in isocubanite (compared with Se, Zn, Ni, and Sn, respectively) is most likely due to the contribution of magmatic fluids from gabbroic intrusions beneath the hydrothermal field. The intrusion of gabbroic magmas would have enhanced serpentinization reactions and provided a relatively oxidizing environment through the dissolution of anhydrite precipitated previously in the reaction zone, within high temperature and low pH conditions. This might have facilitated the extraction of metals by initial hydrothermal fluids, leading to the general enrichment of most metals in isocubanite. Metals in pyrite II have compositions similar to those of isocubanite, except for strong depletion in magmatically derived Te, Cu, Co, and In. This means that serpentinization processes had a dominating role in pyrite II precipitation as well. The enrichment of pyrite II in Mo and Tl is also indicative of seawater contribution in its composition. The study concludes that serpentinization reactions contribute effectively both to high- and low-temperature sulfide mineralization at Tianzuo hydrothermal field, with gabbroic intrusions further promoting high-temperature sulfide mineralization, providing additional metals, fluids and heat. In contrast, low-temperature sulfide mineralization occurred during the cooling of gabbroic intrusions, with decreasing rates of serpentinization reactions and a significant influence of seawater. DA - 2022/01/01/ PY - 2022 DO - 10.1016/j.oregeorev.2021.104421 DP - ScienceDirect VL - 140 SP - 104421 J2 - Ore Geology Reviews LA - en SN - 0169-1368 ST - Trace-element compositions of sulfides from inactive Tianzuo hydrothermal field, Southwest Indian Ridge UR - https://www.sciencedirect.com/science/article/pii/S0169136821004479 Y2 - 2022/09/21/13:41:17 KW - SWIR KW - Serpentinization KW - Sulfide KW - Tianzuo KW - Trace-element KW - Ultramafic rocks ER -