Sulfide metallogenic model for the ultraslow-spreading Southwest Indian Ridge

Polymetallic sulfides present in mid-ocean ridges (MORs) have become important strategic resources for humans, and a scientific metallogenic model is necessary the investigation exploration of these resources. Compared to fast- slow-spreading MORs, ultraslow-spreading MORs show substantial differences magma supply, tectonic activity, oceanic crust structures. However, information on hydrothermal circulation related along still limited, which hinders further In this study, distribution activities, as well characteristics structures, heat sources, fluid pathways, host rock types, properties, sulfide assemblages typical fields Southwest Indian Ridge (SWIR), been studied. It concluded that systems SWIR can be categorized into three including local enhanced magma-controlled, one-way detachment/high-angle large-offset fault-controlled, flip-flop detachment-controlled are five subtypes based their distinct geological backgrounds. Herein, we called Local Enhanced Heat Supply-Deep Faults (eHeat-dFault) SWIR. The overall spreading rate remains almost constant (14–18 mm/year), while supply heterogeneous segment scale Over past two decades, various deposits identified A deep chamber (4–9 km) developed ridge with sufficient owing long-lived active detachment faults (up 13 associated belts segments poor supply. Hence, fulfill conditions sustained source stable pathway formation large-scale polymetallic deposits. number detected area 2–3 times predicted by traditional Spreading Rate-Magma Flux model, demonstrating its significant endowment balance between faulting may influence type depth circulation, frequency activity axis, was previously believed control processes. SWIR, suggest greater than mineralization. eHeat-dFault proposed herein could provide guidance research