Holocene glacier history of the Lago Argentino basin, Southern Patagonian Icefield
Holocene glacier history of the Lago Argentino basin, Southern Patagonian Icefield
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南巴塔哥尼亚冰原拉戈阿根廷盆地的全新世冰川历史
DOI：
10.1016/j.quascirev.2014.06.026
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发表时间：
2014
影响因子：
4
通讯作者：
Schaefer, Joerg M.
中科院分区：
文献类型：
--
作者：
Strelin, Jorge A.;Kaplan, Michael R.;Vandergoes, Marcus J.;Denton, George H.;Schaefer, Joerg M.
我们提出了新的地貌，地层和全新世冰川波动的Lago Restino盆地的南部巴塔哥尼亚安第斯山脉的东侧的数据。年代学控制以~（14）C和~（10）Be定年为基础。在13，000 cal yrs BP的末次冰期最大值之后，充满Lago Loctino东部的大型冰瓣退缩并分离成单独的出口冰川;这种衰退仅在12，200 cal yrs BP时被静止或轻微的再进所打断。其中最大的八个出口冰川从北到南分别是：乌普萨拉、阿加西斯、奥内利、斯佩加齐尼、马约、阿梅吉诺、佩里托莫雷诺和格兰德（以前的弗里亚斯）。全新世乌普萨拉冰川的退缩暴露了Brazo Cristina，超过10，115 ± 100 cal yrs BP，并在9205 ± 85 cal yrs BP到达Agassiz Este Valley的全新世冰碛内侧;冰保持在内侧位置，直到7730 ± 50 cal yrs BP。乌普萨拉冰川和弗里亚斯冰川后来的几次冰川再移动都有很好的记录。乌普萨拉冰川至少再前进了7次，第一次是相对较小的扩张-仅在地层剖面中记录-在7730 ± 50和7210 ± 45 cal yrs BP之间。乌普萨拉冰川最广泛的全新世进展导致了皮尔逊1号冰碛和相关地貌的沉积，这些冰碛和地貌被分为三个系统。皮尔森1a的推进发生在大约6000-5000 cal yrs BP，其次是皮尔森1b和1c的推进，分别发生在2500-2000和1500-1100 cal yrs BP。乌普萨拉冰川的后续发展导致了皮尔逊2号冰碛的沉积和相应的地貌，也分为三个系统，皮尔逊2a，2b和2c，分别构建于公元前700，>400和<300 cal yrs BP到世纪早期。格兰德冰川前的冰碛系统也记录了类似的进展，并在此分为Frías 1和Frías 2a，2b和2c。Onelli和Ameghino冰川谷也保存了更古老的全新世冰碛。在阿加西、斯佩加齐尼和马约山谷，全新世晚期的冰似乎已经覆盖了与皮尔逊1年代相当的地貌。佩里托莫雷诺冰川是一个极端的情况下，冰的历史（皮尔森2c）进步覆盖所有较旧的全新世冰碛。根据保存的冰碛的分布和数量，我们推断，在全新世期间，Lago Algantino出口冰川对气候的响应不同。这促使我们研究气候和非气候因素对个别冰川的影响。因此，我们发现了一个重要的影响，山谷的几何形状（测高）的冰川对气候变化的响应的时间和幅度。这些结果表明，需要谨慎的相关冰碛物之间的冰川前田没有坚定的形态地层和年龄控制。最后，我们注意到重要的相似性和差异之间的整体冰碛年代学在拉戈Albertino盆地和南美洲南部和南半球其他地区。
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. Chronologic control is based on14C and surface-exposure10Be dating. 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. The eight largest of these individual outlet glaciers are, from north to south: Upsala, Agassiz, Onelli, Spegazzini, Mayo, Ameghino, Perito Moreno, and Grande (formerly Frías). 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. Several subsequent glacier readvances are well documented for the Upsala and Frías glaciers. The Upsala Glacier readvanced at least seven times, the first being a relatively minor expansion – documented only in stratigraphic sections – between 7730 ± 50 and 7210 ± 45 cal yrs BP. 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 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 2500–2000 and 1500–1100 cal yrs BP, respectively. 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 ∼700, >400, and <300 cal yrs BP to the early 20th century. Similar advances are also recorded by moraine systems in front of Grande Glacier and herein separated into the Frías 1 and Frías 2a, 2b, and 2c. The Onelli and Ameghino glacier valleys also preserve older Holocene moraines. In the Agassiz, Spegazzini, and Mayo valleys, ice of the late-Holocene advances appears to have overridden landforms equivalent in age to Pearson 1. Perito Moreno Glacier is an extreme case in which ice of historical (Pearson 2c) advances overrode all older Holocene moraines. Based on the distribution and number of moraines preserved, we infer that the response to climate differed among the Lago Argentino outlet glaciers during the Holocene. This led us to examine the effects of climatic and non-climatic factors on individual glaciers. As a consequence, we detected an important effect of the valley geometry (hypsometry) on the timing and magnitude of glacier response to climate change. These results indicate that caution is needed in correlating moraines among glacier forefields without firm morpho-stratigraphic and age control. Finally, we note important similarities and differences between the overall moraine chronology in the Lago Argentino basin and that in other areas of southern South America and elsewhere in the Southern Hemisphere.
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影响因子：
5.3
作者：
Kaplan, Michael R.;Strelin, Jorge A.;Travis, Scott G.
通讯作者：
Travis, Scott G.
巴塔哥尼亚阿根廷拉戈阿梅吉诺谷冰川地质
DOI：
--
发表时间：
1951
期刊：
影响因子：
--
作者：
R. L. Nichols;Maynard M. Miller
通讯作者：
Maynard M. Miller
晚冰期以来一些巴塔哥尼亚冰川的变化
DOI：
--
发表时间：
1968
期刊：
影响因子：
--
作者：
J. H. Mercer
通讯作者：
J. H. Mercer
DOI：
--
发表时间：
1988
期刊：
影响因子：
--
作者：
C. Clapperton;D. Sugden
通讯作者：
D. Sugden
埃玛冰川谷、萨米恩托山、火地岛的全新世冰川
DOI：
10.1016/j.palaeo.2007.12.002
发表时间：
2008
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
J. Strelin;G. Casassa;G. Rosqvist;P. Holmlund
通讯作者：
P. Holmlund