A late Pleistocene glaciolacustrine record was studied at Fagnano Lake (54°35´S, 67°20´W), central Isla Grande de Tierra del Fuego, southernmost South America. Two profiles from the Río Valdéz outcrop were collected for isotopic, geochemical, sedimentological, and geophysical analyses. The sedimentological characteristics, such as rhythmites, presence of dropstones, absence of fossil record, and scarce presence of organic matter, suggest deposition in an ice-contact lake, possibly dammed by the Fagnano paleoglacier. Organic matter of C3 plant origin suggests certain cold and wet conditions. A chronology of the late Pleistocene outcrop was obtained from five 14C ages resulting in an age-depth model. The time span covered 49.01 cal ka BP to 32.14 cal ka BP. Based on the thickness of the deposit and the calculated average sedimentation rate, the glacial environment could have been present in the study area prior to the last glacial maximum, in agreement with the Inútil-San Sebastián paleoglacier. Both glaciers flowed from the same mountain ice sheet in the Darwin Cordillera, which makes it possible to infer a different behavior of this ice cap from those of the Patagonian Andes, perhaps forced by different atmospheric dynamics and proximity to the wet and cold subantarctic air masses.

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阿根廷南部火地岛中部法尼亚诺湖的晚更新世冰湖相 MIS 3 记录

在南美洲最南端的火地岛大岛中部的法尼亚诺湖（54°35´S，67°20´W）研究了晚更新世冰湖相记录。收集了 Río Valdéz 露头的两个剖面，用于同位素、地球化学、沉积学和地球物理分析。沉积学特征，例如韵律岩、滴石的存在、化石记录的缺失和有机物质的稀少，表明沉积在与冰接触的湖中，可能由法尼亚诺古冰川筑坝。C3 植物来源的有机物质表明某些寒冷和潮湿的条件。晚更新世露头的年代学是从五14C 年龄导致年龄深度模型。时间跨度涵盖 49.01 cal ka BP 到 32.14 cal ka BP。根据沉积物的厚度和计算的平均沉降速率，冰川环境可能在最后一次冰川最大值之前存在于研究区域，这与因努蒂尔-圣塞巴斯蒂安古冰川一致。两条冰川都来自达尔文山脉的同一个山冰盖，这使得推断这个冰盖的行为与巴塔哥尼亚安第斯山脉的不同成为可能，这可能是由于不同的大气动力学和接近潮湿和寒冷的亚南极气团造成的.