Iron, copper, and zinc isotopic fractionation in seafloor basalts and hydrothermal sulfides

Studies of the Fe, Cu, and Zn isotopic compositions volcanic rocks sulfides provide an important tool for understanding magmatic, hydrothermal, alteration processes, thereby enabling determination both transition metal sources quantification petrologic environmental impacts hydrothermal activities. In this study, δ56Fe δ57Fe values mid-ocean ridge basalts (MORBs) are higher than those seafloor fluids, while reverse is true δ66Zn δ68Zn values, suggesting that basalt-fluid interactions preferentially incorporate isotopically light Fe heavy into resulting in relative enrichment heavier lighter isotopes altered basaltic rocks. Most (−1.96 to +0.11‰) sulfide minerals within range vent but they significantly lower MORBs back-arc basin (BABBs), was mainly derived from fluids. However, majority chalcopyrite sphalerite pyrite. This suggests high-temperature enriched 56Fe 57Fe, whereas medium- low-temperature depleted 57Fe. Moreover, δ65Cu (−0.88 −0.16‰) (−0.39 −0.03‰) MORBs, BABBs, 63Cu 64Zn were removed fluids incorporated sphalerite, respectively. Consequently, fluid injection deposition can cause Cu plumes, seawater, sediments.