Examination of the distribution of salts in ice free areas of the McMurdo Dry Valleys and Ross Island

The distribution of salts in the ice free areas of south Victoria Land were plotted and the physical and chemical forms of salts accumulating in these areas was established to determine the origin and mechanism of migration of these salts. Detailed and systematic sampling of salt deposits was performed at Capes Evans, Royds and Bird, the Dellbridge Islands, Hut Point Peninsula, Mt Erebus (above the contour approximately 400m bleow the summit), Pearce Valley, Lake Bonney area, the Upper Wright Valley, Shapeless Mountain, Lashly Mountains, Mount Metschel, Alligator Peak, Beacon Valley and Rotunda. More general sampling was performed at Cape Barne, Turks Head, Tryggve Point, Taylor Dry Valley, New Harbour, Marble Point, Lake Vanda area and the Lower Wright Valley. A series of strata of similar form but containing different minerals were also discovered on the Skelton Neve and at Rotunda. Samples of the minerals and the ice host were taken for analysis and crystallography. Samples of salts were collected and sealed into capillary tubes for crystallographic examination. The salt map of the McMurdo Sound area was extended to these new areas and also to the Wright Valley and Marble Point area. Daily samples of the Onyx River were taken during the flow period and were analysed for Na, K, Ca, Mg and Sr in order to obtain an estimate of the annual ion flow into Lake Vanda. Chemical analyses and crystallographic examination was carried out on over 400 collected samples. Salt and soil samples were collected at Mount Kempe, table Mountain, Knobhead, Lake Bonney, Black Island and Mount Erebus Summit including the plateau and crater area and Fang Glacier. Soil temperature and moisture profiles were measured. Systematic sampling on and about mudflows and flooding experiments were conducted at Black Island to determine estimates of the rate of salt movement to the surface in this particular location.