The Coombs area was visited this season to locate and examine remnants of pre-Pleistocene lodgement tills. A study of these deposits was started in 1977/78 by VUWAE 22 and this season's work was a continuation of that programme.

A major find this season was the uncovering of a fossil striated pavement at over 2800 m on Mt. Brooke. This is at least 800 m above the present ice level. This pavement, in conjunction with other evidence from Mt. Feather (Brady and McKelvey 1979) strongly suggests the East Antarctic Ice sheet in Southern Victoria Land predated the Victoria Orogeny. In other words, the mountains are being pushed up through the ice-sheet. The ice-flow direction shown by the pavement is in very close agreement with that determined from the Cenozoic tillite described from Mt. Feather.

The pre-Pleistocene tillite examined at the northeastern end of the Coombs Hills was previously considered to be a Plateau derived remnant of the so-called Sirius Tillite (Mayewski 1975). However, when taking into account the composition of the till stones and comparing these with the geological composition of the Coombs Hills it appears the till can only have been derived from a local neve field in the Convoy Range region, that was drained by an earlier phase of the then expanded Curreen Glacier.

Further Palaeontological and mineralogical investigations of the Cenozoic till are planned.