RESULTS:

Values of the Bouguer anomaly decrease westward from −55 milligals at the mouth of the valley to −137 milligals near the end of the Taylor Glacier. (Table 1) At the eastern end of the valley the gradient of the anomaly is approximately 3 milligals/kilometre, which is comparable with the gradients of 5 milligals/kilometre observed near the coast in the Wright Valley area, (C. Bull, "Gravity observations in the Wright Valley area of South Victoria Land", New Zealand Journal of Geology and Geophysics) and at the eastern end of the ice-free area north of the Koettlitz Glacier. (C. Bull, "Gravity page 2 observations in the Koettlitz Glacier area, South Victoria Land", New Zealand Journal of Geology and Geophysics).

Such gradients are consistent with the existence of a north-south fault line along the coast, the eastern side being down-thrown. It has been considered that the Victoria Land mountain range, bounding the inland ice of eastern Antarctica from latitude 70°S to 85°S, is a horst structure and that the coastal north-south fault line is one limit of the horst. However, geophysical studies on the inland ice west of the Victoria Land mountain range have not provided good evidence for the existence of the fault which should mark the western limit of the horst structure.

The gradients of gravity along the Taylor Valley are also consistent with an abrupt increase in thickness of the crustal material of the earth from a value of about 17 kilometres in the Ross Sea area to about 40 kilometres under the western part of the Victoria Land range. Further geophysical considerations must await the integration of these results with the others previous obtained in the area.