Darwin Mountains

We now move south from the ice-free valleys and the Boomerang Range to the Darwin Mountains of southern Victoria Land adj acent to the Darwin and Hatherton glaciers and north of the Byrd Glacier in Fig. 10.8. This segment of the Transantarctic Mountains also includes the Brown Hills (Section 3.3) where granitic rocks of the local basement complex are exposed. 

The Beacon rocks of the Darwin Mountains were originally described by Gunn and Warren (1962) and were later mapped by Haskell et al. (1964,1965b). The geology of the Darwin Mountains was also included on the geologic map of Grindley and Laird (1969) and was reviewed by Anderson (1979). 

The Beacon rocks of the Darwin Mountains in Fig. 10.9 include both the Taylor and Victoria groups which consist of formations that closely resemble those of the Olympus Boomerang ranges described by McKelvey et al. (1970). The stratigraphic colunm in Table 10.3 is based on information provided by HaskeU et al. (1965b). 

Splettstoesser and Jirsa (1985) reported that an outcrop of the Hatherton Sandstone in the Britannia Range 

The Westhaven Nunatak at the edge of the polar plateau is composed of the Jurassic Kirkpatrick Basalt. Aerial photograph from US Geological Survey, Earth Explorer, US Antarctic Indexes, TMA 1011, roll 00031L, frame 43, November 13, 1962 

---

HaskeU TR, Kennett JP, Prebble WM (1965b) Geology of the Brown HUls and Darwin Mountains, southern Victoria Land. Trans Roy Soc New Zealand 2(15) 231-248 Heimann A, Fleming TH, EUiot DH, Poland KA (1994) A short interval of Jurassic continental flood basalt volcanism in Antarctica as demonstrated by Ar/ Ar geochronology. Earth Planet Sci Lett 121 19 1... 

Fig. 10.8 The Hatherton Glacier flows from the polar plateau between the Darwin Mountains on the right and the Britannia Range on the left. Both mountain ranges in this area consist of sedimentary rocks of the Beacon Supergroup that were intruded by sills of Jurassic Ferrar Dolerite.

Fig. 10.9 Outcrops of the Beacon Supergroup in the Darwin Mountains adjacent to the Darwin and Hatherton glaciers. The Beacon rocks were deposited on the Kukri Peneplain and lie...

Table 10.3 Stratigraphy of the Beacon Supergroup in the Darwin Mountains in the southernmost part of the southern Victoria Land located north of the Byrd Glacier (Fig. 10.9) (Adapted from Haskell et al. 1965b)...

Fig. 10.10 The Darwin Mountains of southern Victoria the geology of the mountain range can be found on this map.

The stratigraphies of the Beacon Supergroup in the Olympus-Boomerang area and in the Darwin Mountains of southern Victoria Land are compared in Table 10.4. 

The Alexandra Formation is present only in the northern Alexandra and Holland ranges as shown in Fig. 10.13 but it does occur in a few areas of the Queen Elizabeth Range and in Holyoake and Cobham ranges of the Churchill Mountains north of the Nimrod Glacier (Laird et al. 1971 Fig. 5.8). The Alexandra Formation correlates with the Hatherton Sandstone of the Darwin Mountains (Table 10.7) and with the New Mountain sandstone in the Olympus-Boomerang area of south-... 

The ice-flow direction is indicated by grooved and striated bedrock surfaces at the base of the Pagoda Tillite and by the orientation of the long axes of clasts. Lindsay (1970a) reported an ice-flow direction of 168 24 (southeast) which is in good agreement with the ice-flow direction of 155 reported by Frakes et al. (1968) for the Darwin Tillite in the Darwin Mountains of southern Victoria Land. 

The Mackellar Formation does not occur in the Darwin Mountains and in the Olympns-Boomerang area because the Mackellar Sea existed only south of these areas (see also Homer and Krissek 1991). 

Gevers TW, Frakes LA, Edwards LN, Mtuzolf JE (1971) Trace fossUs in the lower Beacon sediments (Devonian), Darwin Mountains, southern Wctoria Land, Antarctica. J Paleotol... 

Ross Ice Shelf (Section 3.3). Haskell et al. (1963, 1965) mapped the granitic basement rocks and overlying Beacon rocks in the Brown Hills and Darwin Mountains, but they did not include Butcher Ridge in their study area. 

Haskell TR, Kennett JP, Prebble WM (1965) Geology of the Brown Hills and Darwin Mountains, southern Victoria Land, Antarctica. Trans Roy Soc New Zealand Geology 2(15) 231-247... 

Miotke F-D (1980) Zur Salzsprengung und chemischen Verwitterung in den Darwin Mountains und den Dry Valleys, Victoria Land, Antarctis. Polarforschung 50(l) 45-80... 

---