New Mexico Geological Society Annual Spring Meeting — Abstracts

During late Tertiary and Quaternary times the Southern Foothills of Royal Society Range, Southern Victoria Land, have been glaciated by the repeated advance and retreat of valley glaciers, and, in the topographically lower areas, by higher levels of Ross Ice Shelf. The eruption of small amounts of basanitic lava into this environment has created a range of volcanic landforms, including glaciated, unglaciated, and supraglacial cinder cones and lava flows. Interesting features include channelling and damming of lava flows by the ice edge of former glaciers. Minor pillowed lava and hyaloclastite are present indicating local aqueous environments, but there is no similarity between these volcanics and the large flat-topped tuyas of northwest America and Iceland. This lack of tuyas and voiuminous hyaloclaste deposits in the Southern Foothills area is attributed to: 1) the absence of ice-cap glaciation, 2) the small amount of magma erupted at any particular center.