The East Antarctic Ice Sheet

Antarctica the West Antarctic ice sheet expanded significantly during the LGM (Denton et ai, 1989), while the East Antarctic ice sheet expanded modestly. Concurrent with the growth of major ice sheets was a drop in sea level, with a maximum sea level depression during the LGM of approximately 120 m (Shackleton, 1987). 

Fig. 4.14. Tracing climate change in the Miocene. Shown here are records of ice volume and temperature (based on foraminiferal S 0) and relative organic carbon burial (based on foraminiferal S C), compared with the CO2 estimates of Pagani et al. (1999), and tectonic events that may have affected ocean heat transport. Trends in CO2 are consistent with organic carbon burial and CO2 drawdown during the Monterey Excursion, but cannot explain the Miocene Climatic Optimum (MCO) or expansion of the East Antarctic Ice Sheet (EAIS).

Alley RB, Whillans IM (1984) Response of the East Antarctic ice sheet to sea-level rise. J Geophys Res 89 6487-6493... 

Figure 3. Estimates of atmospheric CO2 levels (PCO2) based on observed isotopic fractionation (Sp) as determined by the 5 C content of individnal alkenone componnds from DSDP site 588. Estimates are based on a phosphate concentration of 0.3 pM and fractionation associated with enzymatic fixation of 27%o. Carbon burial events inferred from the inorganic carbon record are noted with CM, and Mi represents glacial events inferred from the oxygen isotopic record. Data for Sr isotope ratios are from sites 588 (open squares) and 289 (open triangle). Cli. Optimum is climate optimum, EAIS represents the time of the expansion of the East Antarctic Ice Sheet. Error estimates described in the original text represent 15% uncertainty of the calculated PCO2 values. [Used by permission of the editor of Paleoceanography, from Pagani et al. (1999), Fig. 14].

Large meltwater lakes that exist at the base of the East Antarctic ice sheet may be linked by subglacial streams of liquid water. 

Meteorite specimens that land on the East Antarctic ice sheet are transported to the margins of the ice sheet and may be exposed on the bare-ice fields in the zone of ablation adjacent to the Transantarctic Mountains, and at the Yamato and Grove mountains of East Antarctica. In addition, several dozen rock samples from the Moon and from Mars have been collected in Antarctica. 

Mountains of East Antarctica, in the Ellsworth Mountains of West Antarctica, and in the extinct volcanoes of Marie Byrd Land. In addition, small mountain ranges project through the East Antarctic ice sheet in Queen (or Dronning) Maud Land, in Enderby Land, in Mac. Robertson Land, and in a few places in Wilkes Land (e.g., Gaussberg, Section 1.3.3). 

Visitors to Pole Station like to have their picture taken beside a barber pole topped by a silver globe surrounded by the flags of the Treaty Nations (Fig. 2.13). This pole is not at the precise location of the geographic South Pole because the East Antarctic ice sheet is sliding on its base which means that the true position of the South Pole must be redetermined annually. 

Fig. 3.5 The western end of Wright Valley in southern Victoria Land is framed by the Olympus Range in the north and the Asgard Range in the south. Ice from the East Antarctic ice sheet of the polar plateau enters the valley via the Airdevronsix icefaU and forms the Wright Upper Glacier. The Labyrinth at its base was carved by meltwater streams flowing under pressure at the base of a glacier that once flUed the Wright Valley. Lake Vanda is peren-...

Fig. 8.1 The eastern end of the Transantarctic Mountains consists of the Horlick Mountains, the Thiel Mountains, the Pensacola Mountains, the Shacldeton Range, and the Theron Mountains. These mountain ranges are separated from each other by large gaps covered by the East Antarctic ice sheet and in this way occupy about 1,300 km of the total length of the Transantarctic Mountains. AU of these distant mountains have been mapped by geologists (e.g., Mirsky 1969 Davis and Blankenship 2005 Schmidt and Ford 1969 Clarkson et al. 1995) (Adapted from Craddock 1982)...

The Patuxent Range in Fig. 8.6 consists of a large number of nunataks that project through the East Antarctic Ice Sheet in an area of about 6,000 km. ... 

The area between the Thiel Mountains and the Patuxent Range in Fig. 8.6 is covered by the East Antarctic ice sheet which flows through this gap into the Ronne Ice Shelf. The only other mountain ranges associated with the Patuxent Range are the Pecora... 

The Argentina Range is an extension of the Pensacola Mountains along the coast of the Ronne Ice Shelf. This small mountain range consists of three clusters of nunataks located at about 82°20 S and 042°00 W which form the Schneider Hills, Mt. Ferrara, and the Panzarini Hills in Fig. 8.17. The Schneider Hills are separated from the Dufek Massif and the Forrestal Range of the Pensacola Mountains by the Support Force Glacier which channels the East Antarctic Ice Sheet into the Ronne Ice Sheet. 

The location of the Shackleton Range at the edge of the East Antarctic craton and between the Filchner Ice shelf and the East Antarctic Ice Sheet suggests that it should have been glaciated during the Permian Period as well as during the Plio/Pleistocene ice age. 

The Plio/Pleistocene glaciation of the Shackleton Range was caused by ice that originated from three potential sources The East Antarctic Ice Sheet, the... 

The radar-echo surveys of the Antarctic ice sheet by Drewry (1975) provided information about the sub-ice topography but did not detect mineral deposits. More recently, Behrendt et al. (1980) combined the radar-echo sounding technique of Drewry (1975) with an airborne magnetometer survey which revealed that a laige part of the Dufek intrusion in the Pensacola Mountains is covered by the East Antarctic ice sheet. The enlargement of the area of this intrusion increased the amount of potential ore of iron, titanium, and vanadium in this differentiated body of gabbro, pyroxenite, and anorthosite. 

Fig. 14.2 Queen (or Dronning) Maud Land contains groups of nunataks composed of the Jurassic Kirwan Volcanics. The groups of nunataks are identified by number 1, Vestfjella 2, Fossilryggen 3, Mannefallknausane 4, Heimefrontfjella 5, Bjornnutane 6, Sembberget and 7, Kirwan Escarpment. These groups of nunataks rise above the surface of the East Antarctic ice sheet which covers the entire area on this map (Adapted from Fig. 1 of Fumes et al. (1987))...

Fig. 15.1 This bathymetric image of Antarctica was prepared by the National Geophysical Data Center (NGDC) and was last revised July 23, 2008. The coloration of Antarctica reflects the high elevation of the East Antarctic ice sheet which reaches 4000 m above sea level at Dome Argus (81°00 S, 077°00 E).

How far do the sedimentary rocks of the Beacon Supergroup and the mafic igneous rocks of the Ferrar Group extend under the East Antarctic ice sheet ... 

Given the variation in the speed and direction of the wind on Ross Island, the particles in the Erebus plume are dispersed widely such that their surface concentration is below detection. Deposits of volcanic ash that do occur in the East Antarctic ice sheet as well as locally on the surface of valley glaciers and ice caps formed during volcanic eruptions not only of Mt. Erebus but also of the other volcanoes and vents in the Transantarctic Mountains of Victoria Land and in Marie Byrd Land of West Antarctica (Keys et al. 1977 Palais et al. 1982,1983a, b Palais and Legrand 1985 Palais et al. 1989 Radke 1982 Kyle et al. 1982b). 

The total-alkali and silica concentrations of three rock samples from the Adare Peninsula are classified in Fig. 16.36 as a basanite, a phonolite, and a trachyte (McIntosh and Kyle 1990b). Additional chemical analyses by Hamilton (1972), Smith (1964), David et al. (1896), and unpublished data by P.R. Kyle and W.C. McIntosh demonstrate a continuous spectrum of rock types on the Adare Peninsula from SiO = 42% to 67%. The presence of large volumes of palagonitic tuff breccias and pillow breccias on the Adare Peninsula and elsewhere in the Hallett volcanic province led Hamilton (1972) to conclude that these rocks were erupted through ice at a time when the East Antarctic ice sheet had expanded. This interpretation was supported by the presence of abundant glacial erratics on the northern end of the Adare Peninsula (Priestley 1923). 

Apparently, the volcanic rocks on the Adare Peninsula were erupted subaeriaUy rather than subgla-cially although the basal flows may have come in contract with snow and meltwater in a periglacial enviromnent. After the main phase of the eruption, the East Antarctic ice sheet probably did advance from the west and deposited the glacial erractics that cover the northern part of the Adare Peninsula. 

Stump E, Sheridan MF, Borg SG, Sutter JF (1980) Early Miocene subglacial basalts, the East Antarctic ice sheet, and uplift of the Transantarctic Mountains. Science 207 757-758 Stump E, Smit JH, Self S (1986) Timing of events during the late Proterozoic Beardmore Orogeny, Antarctica. Geol. Soc. Amer. Bull. 97(8) 953-965... 

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