Jm. Whitehead et Bc. Mckelvey, The stratigraphy of the Pliocene-lower Pleistocene Bardin Bluffs Formation, Amery Oasis, northern Prince Charles Mountains, Antarctica, ANTARCT SCI, 13(1), 2001, pp. 79-86
In the Amery Oasis of the northern Prince Charles Mountains, the glaciomari
ne Bardin Bluffs Formation of the Pagodroma Group was deposited between the
Late Pliocene (< 3.1 Ma) and Early Pleistocene (>1 Ma). The formation prov
ides evidence of (i) a reduced East Antarctic ice sheet compared to that of
the present day and (ii) a subsequent Plio-Pleistocene ice sheet expansion
. The formation consists of two members. The older, basal Member 1 is c. 12
.5 m thick and consists of relatively ice-distal silty, sandy and sparsely
fossiliferous fjordal strata. Member 1 reflects largely ice-free marine sed
imentation c. 250 km inland from the current Amery Ice Shelf edge. The memb
er is restricted to the area about the north-eastern end of Pagodroma Gorge
where it infills a chemically weathered erosion surface, cut in the form o
f a valley on the Permo-Triassic Amery Group. Weathering occurred during ae
rial exposure of the Amery Oasis in a warmer climate than that of today. Th
e younger Member 2 exceeds 40 m in thickness and is made up of coarse ice p
roximal glaciomarine diamicts. It overlies disconformably Member 1 at Pagod
roma Gorge. Elsewhere, Member 2 rests directly upon a smoothed and striated
erosion surface, cut on the Amery Group, which was part of a fjord floor.
This erosional surface and the facies contrast between the two members, ind
icates an East Antarctic Ice Sheet expansion and Lambert Glacier grounding-
line advance.