IMIS

The summit of Mt. Erebus features several high-elevation geothermal features that are separated from similar features at Mts. Melbourne and Rittman by 350-400 km. Warm fumarolic ground and ice towers on the flanks of Mt. Erebus passively emit steam and CO2 that are believed to have magmatic origins(Wardell et al., 2003). The lower end of Tramway Ridge, located approximately 1.5 km NW of the main crater of Erebus, at an elevation between 3350 and 3400 m, is an extensive warm fumarolic area protected by international treaty as a site of particular biological interest (ASPA 130 Management Plan). At Tramway Ridge, unique communities of photoautotrophic organisms (mosses and cyanobacterial mats) surround fumaroles that reach and maintain year round surface temperatures of 60-65°C, have a neutral to mildly alkaline pH, and are characterized by steep lateral pH and temperature gradients (Broady, 1984; Hudson et al., 1989; Soo et al., 2009).