Robertson Bay Group

The Priestley Formation of the Deep Freeze Range does not correlate with the metasediments of the Robertson Bay Terrane, contrary to a proposal by Nathan and Skinner (1972) who, at that time, had not yet visited the type locality of the Robertson Bay Group in Edisto Inlet (Skinner 1983). It seems more likely that the Priestley Formation is the local representative of the Koettlitz Group of southern Victoria Land because it occupies the same stratigraphic position as the Asgard Formation in the ice-free valleys of southern Victoria Land (McKelvey and Webb 1962 Section 3.1.2) and because both formations contain sedimentary carbonate beds. However, this conjecture has not been confirmed or even tested. 

Fig. 4.14 View of the northern end of the Morozumi Range where light-colored adamellite is in contact with black metased-imentary rocks that were assigned to the Robertson Bay Group by Gair et al. (1969) and by Tessensohn et al. (1981).

Fig. 4.19 The Bowers Terrane occupies the central area of northern Victoria Land flanked by the Wilson Terrane in the west and the Robertson Bay Terrane in the east The major rock types of this segment of the Transantarctic Mountains are identified by capital letters in alphabetical order A = Admiralty Intmsives, B = Beacon Supergroup, BT = Bowers Terrane, G = Granite Harbor Intrusives, P = Galhpoli Porphyries, R = Robertson Bay Group, W = Wilson Group. The Kirkpatrick Basalt has been onritted from this map for the sake of clarity and the Ferrar Dolerite sills are included with the Beacon Supergroup. The Lanterman and Salamander ranges constitute the eastern province of the Wilson Terrane (Adapted from Gair et al. 1969)...

The rocks consist of quartz-feldspar schist and phyllite derived from sedimentary protoliths of the Robertson Bay Group, from the Molar Formation (Sledgers Group), and from metavolcanic rocks of mafic composition. In contrast to the rocks of the Robertson Bay Group, the Millen Schist was multiply deformed (Bradshaw et al. 1982 Jordan et al. 1984 Findlay 1986) presumably during tectonic activity along the boundary fault. 

Robertson Bay Group, Millen Range-Leap Year Glacier, K-Ar ... 

Fig. 4.32 This folded sequence of tuibidite beds of the Robertson Bay Group is located on the north side of Colbeck Bay (71°38 S, 170°05 E) in the southwest comer of Robertson Bay (Adapted from Wright 1981, Fig. 2, p. 131)...

Figure 4.31 Wilson Gneiss, Daniels Range Figure 4.32 Turbidites, Robertson Bay Group Figure 4.33 Beacon Sandstone, Morozumi Range...

Adams CJD, Gabites JE, Wodzicki A, Laird MG, Bradshaw JD (1982) Potassium-argon geochronometry of the Precambrian-Cambrian Wilson and Robertson Bay groups and Bowers Supergroup, northern Victoria Land, Antarctica. In Craddock... 

Burrett CF, Findlay RH (1984) Cambrian and Ordovician conodonts from the Robertson Bay Group, Antarctica, and their tectonic significance. Nature 307 723-726... 

Formation. Therefore, the low-grade metamorphism of the Robertson Bay slates occurred before the metamorphism of the slates of the Swanson Formation. In this way, the K-Ar dates also do not support the hypothesis that the Swanson Formation and the Robertson Bay Group are the same rock unit. 

The apparent failure of the correlation of the Swanson Formation in Marie Byrd Land and the Robertson Bay Group does not necessarily invalidate the hypothesis that Marie Byrd Land moved from a location near northern Victoria Land to its present position in West Antarctica. The paleomagnetic data of Schamberger and Scharon (1972) as well as the evidence for strike-slip motion along the Transantarctic rift postulated by Robinson and Splettstoesser (1986) and by Schmidt and Rowley (1986) virtually require that Marie Byrd Land moved to its present position in West Antarctica in the course of the Late Jurassic to Early Cretaceous break-up of Gondwana. 

Adare Peninsula, HaUett Peninsula, Daniell Peninsula, Coulman Island, and the Possession Islands. The Cenozoic volcanic rocks in these areas are located adjacent to and may have been deposited on top of the low-grade metasedimentary rocks of the Robertson Bay Group of early Paleozoic age (Section 4.5) (Adapted from Gair et al. (1969))... 

P40136, Robertson Bay Group (late-Proterozoic-Cambrian), Antarctica (Nathan 1976). 

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