| dc.contributor.author | De, S. | |
| dc.contributor.author | Singh, S.K. | |
| dc.contributor.author | John, R. | |
| dc.date.accessioned | 2025-12-04 | |
| dc.date.accessioned | 2025-12-04T09:19:49Z | |
| dc.date.available | 2025-11-14 | |
| dc.date.available | 2025-12-04T09:19:49Z | |
| dc.date.issued | 2025 | |
| dc.identifier.citation | Geochemistry, Geophysics, Geosystems, vol.26;2025.;articleno:e2025GC012552. | |
| dc.identifier.issn | 1525-2027 | |
| dc.identifier.other | https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2025GC012552 | |
| dc.identifier.uri | https://doi.org/10.1029/2025GC012552 | |
| dc.identifier.uri | http://drs.nio.res.in/drs/handle/2264/9570 | |
| dc.description | IF2024=3.0 | |
| dc.description.abstract | Hydrothermal systems at mid-ocean ridges (MORs) mediate the transfer of heat and geochemical fluxes from the mantle to the hydrosphere, facilitating fluid-rock interaction and metal cycling. While short-term hydrothermal dynamics are well studied, the long-term response of these systems at slow-spreading ridges to glacial-interglacial sea-level change remains poorly constrained. Here, we measured Pb isotope ratios and trace metal concentrations (Co, Ni, Cr) in authigenic Fe Mn oxyhydroxide coatings from sediment core SSD77-GC03, recovered from the Carlsberg Ridge, to reconstruct hydrothermal activity over the past 49 kyr. Pb isotope compositions of basalt fragments were also analyzed to constrain the local hydrothermal end-members. The Fe Mn coating data delineate six discrete hydrothermal events (HY1 HY6), revealing two distinct modes of sea-level forcing. Events HY4 HY6 (?46 36 ka) follow the Marine Isotope Stage (MIS) 4 sea-level lowstand and reflect a delayed, melt-driven hydrothermal response, consistent with decompression-induced mantle melting and subsequent magma ascent. In contrast, events HY1 HY3 coincided with rapid sea-level falls during the MIS 3 2 transition and Last Glacial Maximum (LGM ? 24 22 ka), and reflect a hybrid mechanism in which fault-enhanced permeability and transient magmatic heat sustained hydrothermal discharges. These dual mechanisms highlight the sensitivity of hydrothermal systems to both mantle melting and upper crustal stress reconfiguration driven by sea-level change. During these events, trace metal enrichments in authigenic coatings indicate enhanced trace metal fluxes to the deep Indian Ocean. Our findings demonstrate that hydrothermal systems at slow-spreading ridges respond dynamically to sea-level forcing and modulate deep-ocean chemistry over glacial-interglacial cycles. | |
| dc.language | en | |
| dc.publisher | Wiley Online Library | |
| dc.relation.isreferencedby | SCI | |
| dc.rights | Only the author version of the copright reserved papers uploaded. Contact drs@nio.org for any complaints regarding copyright violations | |
| dc.title | Millennial-Scale Hydrothermal Variability at the Carlsberg Ridge Driven by Sea-Level Change and Transient Magmatism | |
| dc.affiliation.author | CSIR-National Institute of Oceanography, Dona Paula, Goa, India | |