Sir,
On separate occasions the authors each had the opportunity to ascend Mount Erebus (3,721 m.), Ross Island, the only known active volcano in Antarctica. The ascent by F. C. Ugolini and H. J anetschek in February 1962 was made to study and collect soil samples and biological specimens. The work by G. Holdsworth and G. Lewis in February 1964 aimed at collecting sulphur samples from fumaroles and snow samples at various altitudes.
Although the two parties took different routes, both traversed the extensive area of active and inactive fumaroles at 3,500 m. elevation on the north-west side of the mountain. The fumarole areas offer an unusual spectacle of large ice towers and mounds (Fig. 1). The towers vary in size but they are commonly 6 to 10 m. high and 3 or 4 m. or more in diameter. An aerial view (Fig. 2) shows that some towers have a roughly circular aperture in the crest. Many of the fumaroles were not active during 1962 and 1964, which is in contrast to the situation during the 1908 ascent (Reference David and PriestleyDavid and Priestley, 1914, p. 208−17), but in 1962 a few vents close to the ground were emitting gases. The ice towers are clearly formed by the condensation of the fumarolic vapors. The crystallographic structure of the ice and the stratigraphie distribution of the chemical compounds enclosed therein might preserve part of the late volcanic history of Mount Erebus.
Fig. 1. Inactive fumarolic ice towers (1962)
Fig. 2. Field of fumarolic ice towers. Notice the opening on the tower to the bottom right
Institute of Polar Studies, The Ohio State University,Columbus 10, Ohio, U.S.A.
16 March 1965
