Koettlitz Glacier

Volcanic rocks of Cenozoic age occur also in the ice-fiee valleys located between the Koetflitz and Bine glaciers in Fig. 19.19 (Sections 3.2 and 16.1). Age determinations by Armstrong (1978) indicate that volcanic activity in this area occurred first at about 13.5 0.3 Ma (middle Miocene) and resumed later at about 2.88 0.15 Ma at The Bulwark during the PUocene. The younger volcanic rocks occur primarily on the Dromedary Platform, at The Bulwark, and at The Pyramid in Fig. 19.19. The volcanic activity in this area occurred intermittently and 

Ice-Free Valleys, Koettlitz Glacier, Southern Victoria Land 

A summary of all age determinations of Plio/ Pleistocene volcanic rocks in the ice-free valleys of southern Victoria Land in Fig. 19.20 indicates that the volcanic activity in the Koettlitz-Glacier area started 

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The basement rocks of the ice-free valleys of southern Victoria Land, including the area between the Ferrar and the Koettlitz glaciers farther south in Fig. 3.4, exemplify the structural complexity, lithologic diversity, regional metamorphism, and magmatic activity of... 

The Anthill Formation is about 3,300 m thick (Stump 1995, p. 99) and consists of well-bedded white to grey limestone interbedded with lesser amounts of mudstone, sUtstone, and quartzite. The limestone appears to be unfossiliferous. The metamorphic grade of the AnthiU Formation increases from the greenschist facies on the south side of the Skelton Glacier to the amphibolite facies farther north between the Skelton and the Koettlitz glaciers. 

Fig. 19.20 The Cenozoic volcanic rocks of the McMurdo Volcanic Group in the Wright, Taylor, and Ferrar valleys of southern Victoria Land were erupted between 5.0 and 1.5 Ma (Pliocene), whereas the eruptions in the ice-free valleys north of the Koettlitz Glacier (Fig. 19.19) started at 3.0 Ma and lasted well into the Pleistocene. The eruptions in both areas were subaerial rather than subglacial and occurred after the Transantarctic Mountains of southern Victoria Land had been overridden by the East Antarctic ice sheet (Data from Armstrong 1968 Fleck et al. 1972 Barrett et al. 1992 Wilch et al. 1993b HaU et al. 1993)...

Peninsula, the ice-free valleys along the north side of the Koettlitz Glacier (Garwood, Marshall, and Miers valleys), at the mouth of Taylor Valley, and in the eastern part of Wright Valley. In addition, Ross-Sea drift occurs on Minna Bluff, Black Island, and along the coast of Ross Island (Clapperton and Sugden 1990). 

The principal lakes of southern Victoria Land that attract attention by their size and by the salinities and chemical compositions of the brines they contain are Lake Vida in Victoria Valley (Calkin and Bull 1967), Lake Vanda and Don Juan Pond in Wright Valley, Lake Bonney, Lake Hoare, and Lake Fryxell in Taylor Valley, and Lake Miers in the ice-free valleys along the Koettlitz Glacier (Matsubaya et al. 1979 Matsumoto et al. 1993 Lyons and Finlay 2008). 

Lake Bonney Mummy Pond Lake PopplewelP Lake Chad Lake Hoare Lake Fryxell Lake House Lake Joyce Koettlitz Glacier Lake Miers Lake Pewe Lake Colleen Hidden Lake Lake Keyhole Ward Lake Alpha Lake ... 

Blue glaciers is partially ice-free and exposes metasedimentary and metavolcanic rocks of the Koettlitz Group (Adapted from Bull 1962)... 

Metasedimentary rocks which are common in the ice-free valleys and in the Koettlitz-Skelton Glacier areas occur in the Brown Hills only as scattered inclusions within the Carlyon Granodiorite in the form of dark quartz-biotite-homblende schist and light-colored metaquartzite. A large raft of metasediment, about 10,000 m in area, occurs in the valley between the... 

Fig. 19.19 The area between the Koettlitz and the Blue glaciers in southern Victoria Land consists of mountainous terrain containing several glaciers and snow fields as well as ice-free valleys (e.g., Garwood, Marshall, and Miers) that face the north side of the Koetflitz Glacier. This area contains volcanic vents and small lava domes on the Dromedary Platform, The Bulwark, The Pyramid, and along the Howchin, Walcott, and Radian glaciers (Adapted from Bull 1962a)...

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