Arena Valley

Brook EJ, Kurz MD, Ackert RP Jr, Denton GH, Brown ET, Raisbeck GM, Yiou F (1993) Chronology of Taylor Glacier advances in Arena Valley, Antarctica, using in situ cosmogenic e and °Be. Quat Res 39 11-23... 

Hamilton (1965) reported that the Peneplain and other sills and dikes that intruded the Beacon rocks on New Mountain and Pyramid Mountain along the upper Taylor Glacier are likewise composed of plagioclase, pyroxenes, and opaques with minor quartz and alkali feldspar as well as chlorite and other alteration products. In addition, the Peneplain sill, located east of the mouth of Arena Valley, is also differentiated and includes a pegmatitic zone near its top. The chemical... 

The Miocene deposits consist of till and associated colluvium most of which are older than 11.4 Ma. Both types of deposits are composed of gravelly sand, gravelly mud, or sandy gravel and their thickness ranges from less than 1.0 to about 3.0 m. The clasts are composed of dolerite, sandstone, and granite in about the same proportions as in the Plio/Pleistocene drift of Arena Valley. Only the clasts in the Arena till and the Altar till contain faceted and striated clasts. In addition, the Brawhm till and the Arena till were deposited on striated bedrock. 

Fig. 19.21 The Arena Valley is located in the Quartermain Mountains on the south side of the Taylor Glacier between Windy Gully and Beacon Valley. Arena Valley contains glacial deposits of Miocene and Plio/Pleistocene ages that were dated by the Ar/ Ar method. The glacial deposits of Arena Valley were studied by Marchant et al. (1993a) who concluded The...

In some cases, the volcanic ash in Arena valley was mixed into lobate achalanche deposits and into Quartermain I till. Ash also occurs in thin layers within colluvium and was deposited on the desert pavement of the Monastery colluvium in the central... 

Arena valley. The undisturbed ash is more than 99% pure, whereas the reworked deposits contain more than 50% of non-volcanic contaminants. The ash appears to be unweathered and contains less than 5% of secondary clay indicating that the climate in this area has remained cold and dry since the middle Miocene (Marchant et al. 1993a). 

Selected crystals of sanidine and shards of volcanic glass were dated by the Ar/ Ar method at the Berkeley Geochronology Center. In addition, exposure ages were determined by means of in-situ produced cosmogenic radionuclides (Brown et al. 1991 Brook et al. 1993). The "Ar/ Ar dates derived from volcanic ash in Arena Valley and from sites in the western Asgard Range are listed in Appendix 19.9.1. 

Fig. 19.22 The valleys of the western Asgard Range contain Range as weU as in Arena Valley during the Miocene and PUo/ deposits of till and colluvium of Miocene age. Although these Pleistocene (Marchant et al. 1993a, b). Excerpt from the topo-...

Marchant DR, Denton GH, Swisher CC III (1993a) Miocene-Pliocene-Pleistocene glacial history of Arena Valley, Quartermain Mountains, Antarctica. Geogr Ann 75A(4) 269-330... 

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