ISS010-E-05803 (4 November 2004) - Moreno Glacier, Argentina is featured in this digital image photographed by an Expedition 10 crewmember on the International Space Station (ISS). Similar advances are also recorded by moraine systems in front of Grande Glacier and herein separated into the FrÃas 1 and FrÃas 2a, 2bĮarth Observations taken by the Expedition 10 crew Subsequent advances of Upsala Glacier resulted in deposition of the Pearson 2 moraines and corresponding landforms, also separated into three systems, Pearson 2a, 2b, and 2c, constructed respectively at Ëœ700, >400, and <300 cal yrs BP to the early 20th century. The Pearson 1a advance occurred about 6000-5000 cal yrs BP and was followed by the slightly less-extensive Pearson 1b and 1c advances dated to 00 cal yrs BP, respectively.
The most extensive Holocene advances of Upsala Glacier resulted in the deposition of the Pearson 1 moraines and related landforms, which are divided into three systems. The Upsala Glacier readvanced at least seven times, the first being a relatively minor expansion - documented only in stratigraphic sections - between 7730 ± ± 45 cal yrs BP. Several subsequent glacier readvances are well documented for the Upsala and FrÃas glaciers. Holocene recession of Upsala Glacier exposed Brazo Cristina more than 10,115 ± 100 cal yrs BP, and reached inboard of the Holocene moraines in Agassiz Este Valley by 9205 ± 85 cal yrs BP ice remained in an inboard position until 7730 ± 50 cal yrs BP. The eight largest of these individual outlet glaciers are, from north to south: Upsala, Agassiz, Onelli, Spegazzini, Mayo, Ameghino, Perito Moreno, and Grande (formerly FrÃas). After the Lateglacial maximum at 13,000 cal yrs BP, the large ice lobes that filled the eastern reaches of Lago Argentino retreated and separated into individual outlet glaciers this recession was interrupted only by a stillstand or minor readvance at 12,200 cal yrs BP. Chronologic control is based on 14C and surface-exposure 10Be dating. We present new geomorphic, stratigraphic, and chronologic data for Holocene glacier fluctuations in the Lago Argentino basin on the eastern side of the southern Patagonian Andes. Holocene glacier history of the Lago Argentino basin, Southern Patagonian Icefield
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