Last year I managed a geotechnical investigation to assess the viability of a gravel landing area near Davis Station. A number of instruments were left out at the site about 3km north of the station to continue monitoring the physical environment, including an automatic weather station, subsurface soil temperature loggers, cameras, and open holes for manually measuring water table levels. This season opportunistic work has continued around these installations. In addition, a small-scale geological survey of boulder size and distribution has been conducted to understand the depositional history of the area (which provides clues to drainage patterns etc). Part of the investigation is also to assess the environmental impacts of the survey activities undertaken last season as well as investigations done as far back as the 1980s, so work has very much focused on collection of all relevant data (for example noting the presence/absence of birds and seals in the area).
The area in question is underlain by very old (PreCambrian) metamorphic bedrock called the Mossel Gneiss which has a network of almost equally old striking dolerite dykes intruded through it. The whole region is covered in glacially moved boulders, gravel and sand that were deposited out of the ice sheet that covered the area either during the last ice age (which ended about 20,000 years ago), or, as some believe, during earlier ice ages. The area was also under a few metres of sea only 6–7,000 years ago, so the glacial deposits show some evidence of marine reworking of gravel and sand, with shell deposits amongst it. The soil in the area is very salty as a result, and you can see crusts of salt evaporating from the soil as well as from fresh sea spray throughout the region.
The work this season has been done with fantastic support from the wonderful Davis community. Anyone with technical ability or just an interest has willingly contributed to helping with these tasks, and I would like to express a huge thank you to everyone for their help.
The photos will give you an idea of what work has been done at Davis this summer.
Dr. Barbara Frankel, Antarctic Modernisation Program