Subregions- Agalega Islands region, Mauritius
 - Arabian Sea
 - Broken Ridge
 - Cargados Carajos region, Mauritius
 - Carlsberg Ridge
 - Chagos Archipelago region
 - Cocos Islands region, Australia
 - Crozet Islands region
 - Gulf of Aden
 - Indian Ocean Triple Junction
 - Kerguelen Islands region
 - Laccadive Sea
 - Lakshadweep region, India
 - Maldive Islands region
 - Mauritius region, Mauritius
 - Mauritius - Reunion region
 - Mid-Indian Ridge
 - near the east coast of Sri Lanka
 - near the south coast of Sri Lanka
 - near the west coast of Sri Lanka
 - northeastern Somalia
 - North Indian Ocean
 - off the coast of Somalia
 - Owen Fracture Zone region
 - Prince Edward Islands region
 - Reunion region
 - Rodrigues region, Mauritius
 - Seychelles region
 - Socotra region
 - southeast Indian Ridge
 - southern Kerguelen Plateau
 - South Indian Ocean
 - south of Africa
 - south of Australia
 - Southwest Indian Ridge
 - Sri Lanka
 - Tromelin Islands region
 - western Indian-Antarctic Ridge

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