Cumulus Hills, Shackleton Glacier

The Beacon rocks exposed in the Cumulus Hills along the Shackleton Glacier attracted attention because they contain fossilized bones of large quadruped amphibians and reptiles to be presented in Section 11.1 (Kitching et al. 1972 Hammer and Cosgriff 1981 Colbert 1982 Hammer et al. 1996). The rocks of the Beacon Supergroup in the Cumulus Hills on the east side of the Shackelton Glacier in Fig. 10.18 were 

Fremouw, 735 m Permian Buckley -450 m Fairchild -200 m Mackellar 160 m Pagoda 4-190 m 

The Pagoda Tillite in the Cumulus Hills was deposited on the eroded surface of the local basement complex consisting primarily of the Granite Harbor Intrusives (Chapter 6, Table 6.1). The Pagoda Formation is composed of tillite interbedded with sandstone containing microfloras of Early Permian (or Late Carboniferous) age (Askin and Schopf 1982). Tht Mackellar Formation which overlies the Pagoda Tillite consists of black shale and fine grained sandstone. It was succeeded by the sandstones of the Fairchild Formation, followed by the Buckley Coal Measures. 

The Triassic rocks of the Fremouw and Falla formations consist of interbedded sandstone and mudstone some of which are carbonaceous. The volcaniclastic rocks of the Prehble Formation top the sequence and are overlain by lava flows of the Kirkpatrick Basalt of Jurassic age. The Beacon rocks in the Shackleton Glacier area were intruded by voluminous sills of the Ferrar Dolerite. 

The Falla Formation is composed of sandstone, shale, and tufifaceous beds as defined by Barrett et al. (1986) in the Queen Alexandra Range. In the Shackleton Glacier area only the lower part of the formation is present composed primarily of quartz sandstones which 

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The Early Triassic Fremouw Eormation has yielded fossil bones of a wide variety of land-based amphibians and reptiles that inhabited the forests on the coastal plain of East Antarctica. The collecting sites in the Beardmore and Shackleton glacier areas of the central Transantarctic Mountains include Graphite Peak, Coalsack Bluff, the Cumulus Hills, and the Gordon Valley. The most famous Triassic reptile is Lystrosaurus which was a plump little animal about 90 cm long that seems to have been well adapted to digging burrows in the soil. 

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