Sensitivity of mid-ocean ridge hydrothermal system controlled by the detachment fault to the glacial cycle

Abstract

Changes in sea level caused by glacial cycles may influence the magmatism and hydrothermal activity of oceanic ridges. Recent studies showed that the response time of the hydrothermal activity in the intermediate-fast spreading ridges differs from that in the slow-spreading ridges to the glacial cycles, and a unified model is expected to explain it. Here, we report the 160 ka sediment record adjacent to the Yuhuang hydrothermal field on the Southwest Indian Ridge. Hydrothermal and detachment fault activities were found to enhance or weaken during glacial and interglacial periods, respectively. The magmatism of slow/ultraslow spreading ridges is more sensitive to sea level changes; with the synchronous effect of detachment faults, the hydrothermal activity responds faster to the glacial cycles. We established a model of Sea level change–Magmatism–Detachment fault activity–Hydrothermal activity to explain the different responses of the hydrothermal activity of the mid-ocean ridges to the glacial cycles.