Abstract

During the field season, 1782 volcanic earthquakes were recorded digitally. 247 of which were archived, and 270 video recordings of the crater of Erebus, were made from the TV transmitter on the crater rim. The lava lake continues to exist in the form of three main pools of about 80 m diameter, and degassed and converted freely. However, there were few explosions while K-044 was in Antarctica Fifteen were recorded on both video and digital seismograph, and are presently being analysed by Mr O'Brien for his M.Sc. thesis.

A pilot seismic refraction survey was made on the summit cone along a 200 m line between the upper hut and Nausea Knob. Stacked hammer blows and seismic shots of detonating cord laid on the bare ground surface gave good records out to 100 m distance, and revealed a surface velocity of 3000 m/s. This appears to be the permafrost layer.

The quality of both the seismic and video data improved during the season. The telemetry geophone previously at the summit of Mt. Terror was brought down, serviced, and reinstalled as MACZ on the ESE side of the summit plateau of Erebus by S-081, so the number (6) and distribution of geophones on Erebus has improved. New batteries were added at MACZ and BOMB stations, and the old Gel-cell batteries from Terror were charged and stored at Scott Base. The old Terror site was cleared completely by S-081.

Recording will continue in the Science Lab of Scott Base until the batteries run down in the Winter. Only two of the telemetry sites (Hooper and Cones) have enough batteries to last the winter. The equipment will come back to life next spring when the solar panels recharge the batteries. The WBA infrasonic array recorded well until 3 January, when its RTG was returned to NSF.