The geotechnical properties of Ferrar dolerites

A study of the strength of dolerites in the Dry Valleys region of Antarctica was undertaken in order to define the range of geomechanical properties expressed by these rocks and to examine the relationship between the petrology and strength of the materials. The patterns of jointing were also examined in order to develop an understanding of the development and pattern of joints in relationship to the emplacement history of igneous rocks. Rocks with a wide range of grain size and joint spacing were examined from sites in three main regions: the Labyrinth area of the Upper Wright Valley, the Apocalypse Peaks and Insel Ranges in the Balham Valley and the Beacon Valley. Strength was assessed in the field using a Schmidt Hammer and a Point-load tester, and joint spacing and orientations were measured using line surveys and magnetic bearings.