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A 1:60,000 scale geomorphological map of the Argentine side of the northeastern extreme of Isla Grande de Tierra del Fuego in southernmost South America is presented. This paper describes and summarizes the geomorphology of the mapped area, which includes glacial, periglacial, fluvial, coastal, aeolian, lacustrine, and anthropogenic landforms that span over 680 km2 north of San Sebastián Bay in a sparsely populated semiarid and cold steppe used for sheep breeding and hydrocarbon extraction. We used Landsat-8, Sentinel-2, and ALOS-PALSAR satellite products combined with field validation to create the map. Glacial advances and retreats as well as climatic and sea level fluctuations that controlled fluvial systems and coastal dynamics were the main sculptors of the landscape during the Late Cenozoic. Aeolian, lacustrine, and anthropogenic activity were later minor contributors. The presented free, open access, vector geomorphological map is intended to be a supporting tool for multidisciplinary researchers and decision-makers. [ABSTRACT FROM AUTHOR]

This paper presents a glacial geomorphological map of the landforms created by five large ice lobes that extended eastwards from the southernmost reaches of the Patagonian Ice Sheet during the Quaternary period. The study is focussed on Tierra del Fuego, but also updates previous mapping of the Skyring and Otway lobes, and the resulting level of detail and extent is a significant advance on previous work in the region. The map has been created as the necessary precursor for an improved understanding of the glacial history of the region, and to underpin a programme of dating glacial limits in the region. It was produced using Landsat ETM+ and ASTER satellite imagery and vertical aerial photography, supplemented by Google Earth™ imagery and field-checking. Eleven landform types were mapped: moraine ridges, subdued moraine topography, kettle-kame topography, glacial lineations, irregular and regular hummocky terrain, irregular dissected ridges, eskers, meltwater channels, former shorelines and outwash plains. The map reveals three important characteristics of the glacial geomorphology. First, the geomorphic systems are largely dominated by landforms associated with meltwater (channels, outwash plains and kettle-kame topography). Second, there is a difference in the nature of landforms associated with the northern three ice lobes, where limits are generally marked by numerous clear moraine ridges, compared to those to the south, where hummocky terrain and drift limits prevail. Finally, cross-cutting landforms offer evidence of multiple advances, in places, which has implications for the timing of limit deposition, and thus for the design and interpretation of a dating programme. [ABSTRACT FROM AUTHOR]

Noting the minimal research in South America related to cultural remains which could have become submerged due to sea-level rise at different stages in the past since the Pleistocene–Holocene transition, we take a systematic approach in this article towards making a positive contribution regarding inundated sites and landscapes in Eastern Patagonia and Tierra del Fuego, Argentina. This is a region with a vast continental shelf and high potential for addressing significant archaeological topics such as human migration routes, characteristics of peopling processes, and the use of space and natural resources in the Southernmost part of the American continent. In the context of the latter, the study of submerged landscapes can shed light on past use of the marine environment and its resources. We begin by presenting a regional overview of the archaeological record which can be chronologically and geographically relevant for the topics considered. The characteristics of such record, combined with a general evaluation of coastal and underwater geomorphology as well as other environmental variables, is used to infer some possible targets or "hotspots" with higher potential for past human use as well as preservation of cultural remains. This article provides a basis for further model-developing and ground-truthing surveys. [ABSTRACT FROM AUTHOR]

Understanding the timing of past glacial advances in Patagonia is of global climatic importance because of the insight this can provide into the influence on glacier behaviour of changes in temperature and precipitation related to the Southern Westerlies. In this paper we present new luminescence ages determined using single grains of K-feldspar from proglacial outwash sediments that were deposited by the Patagonian Ice Sheet around Lago Buenos Aires (∼46 °S), east of the contemporary Northern Patagonian Icefield. The new luminescence ages indicate that major outwash accumulations formed around ∼110 ± 20 ka to 140 ± 20 ka and that these correspond to the Moreno I and II moraine ridges, which were previously dated using cosmogenic isotope dating to 150 ± 30 ka. Luminescence dating at Lago Buenos Aires has also identified outwash sediments that were deposited during glacial advances ∼30.8 ± 5.7 ka and ∼34.0 ± 6.1 ka (MIS 3) that are not recorded in the moraine record. Younger outwash accumulations were then deposited between ∼14.7 ± 2.1 and 26.2 ± 1.6 ka which correspond to the Fenix I – V moraine ridges. The combined chronology suggests that glacial advances occurred ∼110 ± 20 ka to 150 ± 30 ka (MIS 6), ∼30.8 ± 5.7 ka to ∼34.0 ± 6.1 ka (MIS 3), and ∼14.7 ± 2.1 to 26.2 ± 1.6 ka (MIS 2) at Lago Buenos Aires. Overall luminescence dating using single grains of K-feldspar has excellent potential to contribute towards the ever-increasing geochronological dataset constraining the timings of glacial advances in Patagonia. [ABSTRACT FROM AUTHOR]

We map the glacial geomorphology of the former Patagonian Ice Sheet between 44°S and 46°S. Building on previous work, our map covers a ~50,000 km² region of west-central Patagonia. The study area includes the eastward-flowing Río Pico, Río Caceres, Río Cisnes, Lago Plata-Fontana, El Toqui, Lago Coyt/Río Ñirehuao, Simpson/Paso Coyhaique, and Balmaceda palaeo-outlet glaciers, adjacent valleys, and the Andean Cordillera. The inventory contains >70,000 individual landforms mapped from remotely-sensed imagery and field surveys. Mapping was classified into ice-marginal (e.g. moraine ridges, trimlines), subglacial (e.g. glacial lineations, flutes), glaciolacustrine (e.g. palaeolake shorelines, perched deltas), glaciofluvial (e.g. proglacial outwash plains, meltwater channels), and non-glacial (e.g. palaeochannels, landslides or slumps) landform groups. The new map will inform future interpretations of regional glacier dynamics, and the development of robust geochronological datasets that test the timing of glaciation and deglaciation. [ABSTRACT FROM AUTHOR]

This study presents the first detailed glacial geomorphological map of the sediment-landform assemblages formed by three eastern outlet glaciers of the former Patagonian Ice Sheet. These glaciers occupied the Río Corcovado, Río Huemul and Lago Palena/General Vintter valleys, Chubut province, Argentina (43°S, 71°W). By combining remote sensing and field-mapping, we build on previous ice-sheet scale mapping and geological surveys to provide high-resolution spatial information on local ice-contact glaciogenic, glaciofluvial, glaciolacustrine, and subglacial landforms. Twenty-five landform types, many of which are newly mapped in the region, were digitized as georeferenced shapefiles over a 5300 km2 area. This map enables the identification of former ice-flow directions, relative ice-margin positions and glaciofluvial drainage pathways for each preserved Quaternary glaciation. It also elucidates the former areal extent, geolocation and spillways of glaciolacustrine bodies formed during the last deglaciation. The map delivers an essential framework on which to build robust glacier-scale geomorphological and geochronological reconstructions. [ABSTRACT FROM AUTHOR]