hydrothermal vents are found at a number of sites within the crater with varied characteristics, including high and low temperature vents. the bulk of the venting occurs through the a complex known as the northern moat hydrothermal complex and reaches temperatures of , while another complex, called the south wall fe chimney, vents water with temperatures of in massive vents. the hydrothermal activity influences the waters within the crater, making them turbid and warmer than the water in the free ocean. low temperature hydrothermal vents are found on the western ridge of vailulu'u as well.