Victoria University Antarctic Research Expedition Science and Logistics Reports 2000-01: VUWAE 45

Allan Hills: (Figure 2)

Allan Hills: (Figure 2).

a)	A ledge on Weller sandstone was discovered immediately northwest of "Boulder Ridge", which had impressive striae, grooves, rat tails, chattermarks (within grooves), and nail head striae caused by a southward advance of the Manhaul glacier at some time after deposition of the Sirius Group. These erosional features are associated with immature diamict and suggest that, at this place, the Manhaul was not cold based. A future Master's thesis could be done mapping the diamict and erosional evidence of the Manhaul, Odell, and other glacial lobes issuing from the main East Antarctic Ice Sheet. Surface exposure dating of stones in the diamict would be useful to reconstruct the timing of these post-Sirius glacial events. Sandstone boulder dispersal trains in Trudge Valley by the Manhaul Glacier, and quartzite by the Odell Glacier, further attest to the dynamic behaviour under those glaciers.
b)	The ridge under the Odell glacier that parallels Trudge Valley may have been formed by the Odell overriding the dolerite dyke that crosses the valley at that place. Subsequently, the Odell may have dumped and streamlined sediment on the lee side of the dyke - the ridge could be a 'crag-and-tail' feature.
c)	The ridges on the "Triangle" resemble recessional (ribbed) moraines.
d)	Abundant roches moutonnees were discovered on the sides and bottoms of the SE gully, and adjacent gully to the northwest where Bornholdt worked. These are cirque basins that had local ice flowing downhill into Trudge valley.

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