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This paper presents the results of a study on the isotopic ecology of guanacos in central western Argentina. We examine the historical population ecology of guanacos using stable isotope analysis of bone collagen from pre-Hispanic and modern guanaco populations (n = 129), considering variability in two ecoregions: the Monte hot desert and the Andean-Patagonian cold desert. Our study addresses the consistency of guanaco diets over time, evaluating palaeoecology to provide information for conservation of this taxon. We found significant differences in isotopic niche size between modern and archaeological guanacos. When analyzed by ecoregion, there were significant differences in niche size through time, indicating that guanacos had distinctive dietary habits and occupied different ecological niches across the ecoregions. Comparing Standard Ellipse Areas (SEA) through time and across space, we observed that the archaeological SEA for guanacos is smaller than its modern counterpart in the Andean-Patagonia ecoregion. Conversely, in Monte, the archaeological SEA is larger than the one established for modern samples. The contrast between pre-Hispanic and modern populations highlight the impact of human activity and conservation efforts on the distribution and ecology of guanacos. These findings have important implications for understanding guanaco ecology with consequences for conservation policies. [ABSTRACT FROM AUTHOR]

The Salado and Verde streams constitute the two main seasonally available freshwater courses that flow into the Atlantic coast of the Río Negro province (continental Patagonia, Argentina, 42° South). This would have favored their use in the past as corridors for human circulation between the coast and the interior. This paper presents the results of the technomorphological and geochemical analyses of the obsidian artifacts recovered in the area to constrain mobility. The results allow us to propose the existence of toolkit reconditioning or replacement activities, and the identification of different sources of provenance of the obsidians (Sacanana, Telsen, and Portada Covunco, distant up to 800 km from the study area), reinforcing the hypothesis of a coast–inland circulation, with the possible existence of circuits of exchange of this raw material. [ABSTRACT FROM AUTHOR]

Background and aims: The Funga of the Patagonian Nothofagus forests is being studied since the late 19th century, but despite many efforts is still far from being completely known. The aim of this paper is to present detailed descriptions and data on geographical distribution of some genera and species of mitosporic ascomycetes that constitute new records for Argentina and for the Neotropical Region. M&M: Bark and woody debris from native Nothofagaceae were collected and studied. Reproductive structures were hand-sectioned and examined following traditional mycological techniques. Results: Six species of mitosporic ascomycetes were identified: Avettaea salvadorae, Bactrodesmium atrum, Dwiroopa ramya, Gilmaniella multiporosa, Monodictys paradoxa and Pycnopeziza quisquiliaris. Full descriptions, comments on identification and data on distribution and habitat of each species are provided, along with photographs illustrating diagnostic features. Conclusions: Two genera, Dwiroopa and Pycnopeziza, and one species, M. paradoxa, are registered for the first time in the Neotropical Region, two other species are first recorded in South America (B. atrum and G. multiporosa). This constitutes the second record of A. salvadorae in the continent, thus expanding its area of distribution. [ABSTRACT FROM AUTHOR]

Bioarchaeological research of bone growth patterns provides information on the health status and disease of past populations. Recent studies have pointed out the potential of metric analysis of nonadult vertebrae as indicators of stress during different stages of ontogeny, highlighting that most vertebral measurements present low sexual dimorphism, a stable and known pattern of growth and give useful information even in incomplete spines. The aims of this paper are first, to construct a vertebral growth profile for nonadults of a skeletal series of Patagonian Late Holocene hunter‐gatherers from Salitroso Lake (SAC); second, to compare it to the ones obtained in other archaeological and modern populations with different stress experiences; and third, building on this, to assess whether individuals with evidence of stress experienced in early development demonstrate different patterns in vertebral growth than those without. Two spinal dimensions are used: vertebral body height (VBH) and transverse diameter of the neural canal (TDNC) in a sample of 23 nonadult skeletons with ages previously estimated from dental and bone indicators. The vertebral dimensions of 20 adults between 18 and 35 years of age were also measured as reference information. Results show that the growth of the VBH is steady over the years and reaches adulthood size by approximately 16 years of age whereas TDNC dimensions do not experience marked fluctuations in size throughout life and adult dimensions are reached at approximately 4 years of age as expected. The vertebral growth pattern observed in SAC is similar to that obtained in other archaeological samples from very different settings but experiencing relatively high nutritional or pathological stress in early stages of life. However, it is markedly different, and systematically smaller, to the 20th century sample pattern, probably responding to a secular trend in the modern population with a more stable access to resources and medical treatment. Finally, SAC individuals with systemic stress markers do not tend to exhibit smaller vertebral dimensions than those without them. [ABSTRACT FROM AUTHOR]

In Argentina, the myths of the European origin of its population and the extinction of the original peoples have been in force for 140 years. They have had explanatory force to deny not only rights to native peoples but also to publicly affirm their very extinction. Since the end of the last military dictatorship (1976-1983) and the return of democracy, the existence and rights of native peoples have been recognized. At the same time, there was a strong criticism of the entire historiographical account that had supported these myths. However, in the present, the debate about history continues. In the current context of political confrontation between different models, we find new discourses that articulate old explanations based on those myths. After the tendency to criticize the traditional discourse, new revisionist and denialist proposals have been established, anchored in the current political context. These reuse and redefine the stereotypes of foreign and Chilean indigenous peoples, the myth of innate violence and the illegitimacy of the claim of rights by native peoples. These discursive constructions accompany a process of increasing violence towards the organizations and demands of the original peoples in Patagonia, where the Mapuche people are identified as an internal enemy. In this paper we propose to address this context taking into account the scientific production on the historical process of indigenous subjugation and incorporation into the state-nation-territory matrix in Argentina, focusing especially on the case of Patagonia and the Mapuche people. [ABSTRACT FROM AUTHOR]

In order to understand the paleogeographic evolution of Viedma Lake (252 masl) sedimentary sequences with glaciolacustrine and lacustrine strata between 307 masl and 266 masl and bathymetric fluctuations between 27 ka. and 2.4 ka. were identified. The paleoenvironmental interpretation of the stratigraphic profiles was carried out based on the analysis of facies and their associations. The oldest age was recorded at 301 masl (27 ka) and the youngest corresponds to 266 masl (2.4 ka). The record of 27 ka was compared with another dated record of the Tar-San Martin Lakes basin showing that Viedma – Tar-San Martín Lakes were formed at similar ages. Taking into account that the deposits of Bahía Túnel are located at 266 masl and that the level of the lake would be above this height, it is proposed that this lake level would have restricted the movement of hunter-gatherer populations along the coast and to the west. From 2.4 ka on a new space started to be available for these populations broadening the wintering grounds (≤400 masl). The chronology of the archaeological record found in this new space fits the proposed paleogeographic evolution. This paper complements the research on the evolution of lacustrine systems in the Patagonian Mountain range and broadens the discussion of human mobility in the Viedma Lake basin during the Holocene. [ABSTRACT FROM AUTHOR]

Nowadays, wildlife is one of the most important sources of zoonoses, and it is a major concern for public health. Nevertheless, little is known about the role of wildlife as a reservoir and source of infectious diseases in the past. South America presents a wide diversity of wildlife. In the south of the continent, Argentina shelters a large diversity of neotropical carnivores. Although the paleoparasitological studies on carnivores have been increasing in southern Argentina, most of the efforts have been focused in a handful of sites located in western Patagonia. In this paper, two coprolites of felid found in Cueva Galpón, an initial late Holocene mortuary site from northeast Patagonia (Argentina), were studied for paleoparasitological purposes. Samples were processed by rehydration and homogenization, filtered and processed by spontaneous sedimentation. The samples were assigned to Puma concolor (puma) or Panthera onca (jaguar). Microscopic observations revealed that both coprolites were positive for parasite remains. High parasite richness was observed. Six nematodes, one cestode, and one coccidian morphotypes were reported. This is the first time that Gnathostoma sp. and Spirocerca sp. were recovered from holocenic times from Patagonia. This finding implies that some diseases such as taeniasis, spirocercosis, gnathostomosis, ascariasis, and coccidiosis could be present in holocenic wildlife from Patagonia prior to the Spanish colonization and domestic animal introduction. The overall results suggest that felids could have played a role as reservoirs and source of some parasitic species, some of which are zoonotic. Therefore, this animal could have entailed a risk agent for human health in the site. [ABSTRACT FROM AUTHOR]

The Magallanes-Austral Foreland Basin preserves an important record of orogenesis and landscape evolution in the Patagonian Andes of Chile and Argentina. This paper evaluates the comparison between the thick Paleogene sequences in the Chilean Peninsula Brunswick (Chorrillo Chico and Agua Fresca formations) and the reduced Paleogene sequence (La Barca Formation) in the Punta Ainol locality, Argentina, by taking account of palynological and geochemical analyses. Warm and humid subtropical conditions (Subtropical Gondwanic Paleoflora) are inferred for the late Paleocene-Eocene interval studied. A new record of Lactoridaceae in the La Barca Formation expanded the known fossil range of this family in Patagonia. During the late Paleocene the Chorrillo Chico and La Barca formations would have been deposited mainly from hyperpycnal flows and this accumulation process continued until the Lutenian in the La Barca Formation. A relative rise in the sea level in the early Eocene would be recognized in both sections. In the middle Eocene a relative fall in the sea level would have occurred with increased terrigenous influx. The rate of sedimentation was similar in both sections during the Thanetian and Ypresian intervals according to the ages assigned by biostratigraphy, suggesting that the sedimentation rate would have been controlled mainly by relative changes in sea level during the Paleocene-Eocene transition. Paleoenvironmental changes during the Paleocene-Eocene transition were characterized at the La Barca Formation of the Punta Ainol section, considering the new geochemical and palynological data provided in this contribution. • A new register of early Paleogene flora of Patagonia. • Paleogeographic changes based on palynological and geochemical data. • New geochemical inferences of the Paleocene-Eocene transition in South America. • A new Paleocene-Eocene record from Southern Hemisphere. [ABSTRACT FROM AUTHOR]

The relationship between climate and tourism has implications at all spatial scales. Yet the climatic sensitivity of tourism varies according to place-specific tourism types in which it takes place and activity type. Therefore, from comfort approach, the climatic features of destination are an important resource for planning. This paper evaluates the climate comfort of Argentina as an intangible resource for tourism. The analysis builds on spatial modelling of the Tourism Climate Index (TCI), calculated for 69 weather stations uniformly distributed throughout the country. The mean annual TCI in Argentina is 73, indicating "very good" climatic-tourist comfort conditions for tourism. However, the spatial distribution of the index exhibits a maximum diagonal band and two mirror regions defined by decreasing scores towards NE and SW. This is attributed to the spatial distribution of the sub-indices conforming the TCI. Daily thermal comfort and wind speed negatively influence Patagonia, while in Litoral, they counterbalance the high amounts of precipitation. These findings show the importance and interest of considering the climate as a strategic resource in national tourism planning. [ABSTRACT FROM AUTHOR]

This paper analyses a collection of engraved plaques from Golfo San Matías (Río Negro province) in order to assess design recurrences which might point to the presence of ornamentation rules and/or visual information coding among the hunter-gatherer peoples who produced and used them. Then, 170 plaques from Patagonia and other regions of Argentina are systematically compared using the presence of shared motif types as the main criterion. Data are assessed using a theoretical model with expectations which link design variability/standardization, ornamental laxity/structuration and informational heterogeneity/redundancy. Results show that plaques display low design standardization, which is compatible with a low redundancy communicative function (heterogeneous content) and/or with an ornamental function with lax rules. Moreover, the shared repertoires document several inter-regional links, which are verified using different lines of archaeological evidence. [ABSTRACT FROM AUTHOR]

Well-preserved and diverse Early Cretaceous palynological assemblages were studied from an outcrop section of the Springhill Formation at the Río Correntoso locality (PRC), close to Ghío Lake, in Santa Cruz Province, Patagonia, Argentina. The studied log corresponds to the northernmost outcrops known for the Springhill Formation in the Austral Basin. Most of the palynomorphs algae (Botryococcus, Sphaeroplea, Lecaniella, Zygnema, Pseudoschizaea, Schizosporis, Ovoidites), and some angiosperm pollen grains (Proxapertites , Longapertites, Arecipites) are distinctive and characterize the palaeoenvironment and palaeoclimate of PRC, which was dominated by estuarine coastal margin sedimentites deposited under warm and humid conditions. These angiosperm pollen grains correspond to the earliest record of these group in Patagonia, represented by diverse monosulcates and one rare tricolpate type. This new record of angiosperm pollen in the Springhill Formation provides further evidence that one of the earliest diversifications of angiosperms started at least during the early Cretaceous in Patagonia. Sergio Archangelsky provided an invaluable expertise in the field of paleobotany in multiple ways. His knowledge transcended not only through his papers but also through his exceptional oratory skills. His talks were always enriching in every aspect, combining an engaging historical account with a vision towards the future. "...La paleobotánica un placer, debe ser algo agradable, es decir uno cuando trabaja en paleobotánica le gusta lo que hace, y cuando uno está describiendo, uno se va, y es lo mismo que componer una pieza musical, te perdés, te perdés en todo y lo hacés con gusto, con pasión..." "...The paleobotany is a pleasure, it should be something enjoyable, meaning that when you work in paleobotany, you love what you do. And when you're describing, you get lost, just like composing a musical piece. You lose yourself, in everything, and you do it with pleasure, with passion...". The file with the voice of Sergio Archangelsky is in Supplementary file under Sergio_Archangelsky.mp3. • The palynoflora of the Springhill Formation includes algae and land plants. • Pollen records show features of early members of some taxa (monocots and eudicots). • Angiosperm pollen grains provides evidence for early radiation of some basal taxa in Patagonia. • Palynoflora studied indicates freshwater palaeoenvironment, warm and humid climate. [ABSTRACT FROM AUTHOR]

Patagonia features the most extensive glaciers of the Southern Hemisphere, excluding Antarctica, and a vast inventory of glacial landforms, so it is thought to have played a key role in (paleo)glacier studies since the late 19th century. However, no systematic attempts to characterize the specific research trends and the scientific community focused on Patagonian cryosphere have been conducted so far. To fill this gap, we analyzed the metadata associated to 305 articles compiled from the Web of Science database following a bibliometric approach covering the period between 1976 and 2020. Our results point to an irregular but net increase on the number of contributions on Patagonian (paleo)glaciers. Mass balance analyses based on satellite data of present-day glaciers and the reconstruction of past glacier activity by dating glacial landforms formed during the Last Glacial Termination, were the most addressed topics during the analyzed period. Patagonian (paleo)glacier studies are mostly published in generic Earth Sciences publications, followed by Quaternary and glaciological journals. Most of the studies were led by scientists from the United Kingdom, followed by Chile, Argentina and United States. In terms of collaborations, these studies can be divided into two main clusters, one composed by researchers from United States, Chile and Argentina institutions, and another mostly composed by British researchers. So far, the most prolific authors are nearly equally distributed in nationality, yet gender inclusion and international collaborations are still caveats that must be solved. Even though our query on the Web of Science missed highly influential (so-called) grey literature, such as local scientific journals and technical reports, the reviewed scientific literature unambiguously indicates that Patagonia is a privileged location for (paleo)glaciers studies worldwide and that it will continue offering vast opportunities to tackle critical questions related to global cryosphere and past-to-present climate changes. • Patagonia is a privilege site for studying present and past glacier dynamics and the evolution of climate changes at hemispheric and global scale. • Glacier dynamics during the 20th century and and the Last Glacial Termination are the most common topics addressed in past decades in the WOS. • Patagonian (paleo)glacier studies has contributed to the development or improvement of diverse analytical techniques. • United Kingdom, United States, Chile and Argentina produced the largest number of WOS-listed papers on (paleo)glaciers in past decades. • The related scientific community is fairly heterogeneous. Although, inclusion and international collaboration issues still need to improve. [ABSTRACT FROM AUTHOR]

• Six obsidian sources increased their use in the Late Holocene in north Patagonia. • The closer source to Diamante Valley, is the least used. • The best quality source, Las Cargas, was the most used across the Late Holocene. • Obsidian helped to minimize risk in the occupation of high elevation locations. • Obsidian exchange routes may find a pattern in least cost path analysis results. • Exchange of obsidian followed routes through High elevations villages to sources. In this paper we explore obsidian conveyance in the Diamante Valley, in northwestern Patagonia, Argentina. Obsidian is the third most-common toolstone used in the Diamante Valley after basalts and local cryptocrystallines. Obsidian artifacts are predominantly projectile points and bifaces, with few cores and early-stage reduction debris. To explain these patterns, we conducted XRF sourcing and technological analysis of 177 obsidian artifacts collected there. We also conducted a GIS-based least cost path analysis to assess the costs of conveying obsidian from sources to sites in the Diamante watershed. We found that hunter-gatherers used Las Cargas as the principal obsidian source, followed by Maule 1 and 2, El Peceño, and Coche Quemado. The nearest source, Laguna del Diamante, was the least used. These data, combined with an analysis of the ways cores, formed tools, and debitage types were conveyed and ultimately deposited at sites in the Diamante watershed, suggest a late Holocene pattern of highland-oriented indirect access, implying highland village sites likely served as nodes in a regional and extraregional exchange network focused not only on obsidian but also on other goods, information, and social obligations. [ABSTRACT FROM AUTHOR]

• Dryline formation is favoured by the advection of mid-level dry air from the Pacific. • Local circulations impact the dryline movement and strength in quiescent conditions. • Nocturnal LLJ and local circulations reinforce the moisture gradient at night. • In synoptically active periods, dry advection and diurnal mixing are more important. Drylines are a frequent feature of the atmospheric circulation in Argentina. Recent work described their climatological characteristics and synoptic-scale processes associated with their formation. However, little is known about the mesoscale processes that are relevant for their life cycle. In this paper, we investigate the influence of these mechanisms on the formation and movement using a case-study approach. Also, the relationship between these mechanisms and convective initiation near the dryline is investigated. A typical northern Patagonia dryline is simulated using the Weather Research and Forecasting (WRF) with an horizontal resolution of 3 km. The FLEXible PARTicle dispersion-WRF is also used to study some of the processes from a Lagrangian perspective. During the quiescent period corresponding to dryline formation and intensification, the dryline strengthens along the axis of a thermally-induced surface trough that promotes differential moisture advection. Also, convergence along the dryline is enhanced during night-time by the inertial oscillation ahead of the dryline and by the development of a thermally-driven circulation between the elevated terrain in northern Patagonia and the adjacent plains. These two mechanisms contribute to enhancing the intensity of the moisture gradient and to trigger deep moist convection. Under a period of stronger synoptic forcing, the dryline intensifies in response to the confluence induced by the deepening surface trough and moves away from the terrain elevations. Its movement during this period is driven by horizontal dry advection and the vertical mixing enhanced by the entrainment into the boundary layer of extremely dry air, whose origin can be traced back to the mid-levels over the Pacific Ocean. When the magnitude of the low-level westerly winds increase, moister air from lower levels cross the barrier, contributing to weakening the moisture gradient at the dryline. [ABSTRACT FROM AUTHOR]

The western slope of Cerro Domuyo in northern Patagonia is characterized by thermal springs with boiling waters, Quaternary silicic domes, and pyroclastic deposits that suggest the existence of a geothermal reservoir. According to geochemical studies, the reservoir may have a temperature of 220 °C and one of the largest advective heat fluxes reported for a continental volcanic center. In this paper, we propose a more refined conceptual model for the Domuyo geothermal area, based on a geological survey supported by U Pb, U Th, and Ar Ar geochronology and by magnetotelluric and gravity surveys. Our study indicates that the Domuyo Volcanic Complex (DVC) is a Middle Pleistocene dome complex overlying middle Miocene to Pliocene volcanic sequences, which in turn cover: 1) the Jurassic-Early Cretaceous Neuquén marine sedimentary succession, 2) silicic ignimbrites dated at ~186.7 Ma, and 3) the Paleozoic metamorphic basement intruded by ~288 Ma granite bodies. The volcanic cycle in the DVC is distinctly bimodal, characterized by the emplacement of massive silicic domes and less voluminous olivine basalts on its southern slope. A major collapse of the central dome at ~600 ka produced a voluminous (19.4 km3 and 133 km2) block-and-ash flow, and associated pyroclastic flows, that filled a valley to the southwest at distances up to ~30 km from Cerro Domuyo summit. This was followed by a period of intense effusive activity that formed the Cerro Guitarra, Cerro Las Pampas, Cerro Domo, and Cerro Covunco silicic domes. The last two domes are the youngest and largest edifices, dated at 0.50 Ma (Ar Ar age) and 0.25 Ma (U Th age). Pre-Cenozoic successions were affected by N-S reverse and thrust faults that were later displaced by an ENE-WSW-trending transtensional belt. The basement rocks at the northern termination of the Cordillera del Viento anticlinorium were also displaced towards the east-northeast by this belt, which is observed NNW of Cerro Domuyo. The DVC was emplaced within this zone of crustal weakness. The integration of geologic observations with magnetotelluric and gravity data, allowed us to develop an updated conceptual model of the geothermal system. The geothermal reservoir is inferred at a depth of less than 2 km within pre-Pliocene fractured rocks, bounded by ~WSW-ENE trending faults and sealed by the pyroclastic deposits and rhyolitic lavas of the DVC. The location of most thermal springs is not directly controlled by faults. Instead, flows emerge at the contact between the fractured and faulted basement and the caprock. • The Domuyo Volcanic Complex (DVC) is a silicic dome complex formed in the Pleistocene. • The central dome collapsed at ~600 ka producing a voluminous (19.4 km3) pyroclastic deposit. • The youngest domes were emplaced at ~500 ka and 250 ka. • The DVC was emplaced within a ENE-WSW trending transtensional zone of crustal weakness. • The geothermal reservoir is hosted in pre-Pliocene rocks sealed by the DVC pyroclastics and lavas. [ABSTRACT FROM AUTHOR]

The South Atlantic coast in Argentine Patagonia is an area where semi-arid to arid conditions predominate and coastal populations present serious water supply problems. The aim of the work was to evaluate the factors that condition the salinization processes of coastal aquifers from a hydrochemical and isotopic analysis of the groundwater located in Pleistocene and Holocene littoral ridges in the northern sector of Patagonia in Bahía San Blas. A geomorphological characterization of the area was carried out using digital elevation models, satellite image interpretation and field surveys. Groundwater chemistry was analyzed in 40 shallow wells and 2 tidal water samples. At each point, electrical conductivity, temperature and pH of water were measured and samples were taken for analysis of major ions and stable isotopes. The salinization processes were analyzed by means of ionic and isotopic relationship graphs and were subsequently modeled using free software. The results obtained allowed the identification of the factors that determine the salinization of coastal aquifers. Particularly in the Pleistocene coastal ridges, the cementation of the most superficial sediments reduces permeability conditioning rainwater infiltration. This, together with the presence of soluble salts on the surface and the mixing with sea water, determines the salinization of the groundwater. In contrast to these, in the Holocene coastal ridges without cementation, rainwater infiltrates forming freshwater lenses where salinization processes occur only at the edges of the lenses where the saltwater wedge is located. The data provided in this paper are useful in prospecting freshwater sources along the arid coast of Patagonia where freshwater availability is scarce. They can also be extrapolated to other sectors worldwide with similar geological and climatic environments. • Water supply problems exist in the arid coastal zone of Patagonia Argentina. • Freshwater lenses are formed in Pleistocene and Holocene littoral ridges. • Groundwater salinization is recognized in lenses of Pleistocene littoral ridges. • Salinization processes are due to cementation, salts dissolution and marine intrusion. [ABSTRACT FROM AUTHOR]

The general trend of glacial retreat since the Little Ice Age has shown an acceleration during the last decades in Southern Argentine and Chilean Patagonia. The Fuegian Andes climatic records report an irregular mean annual temperature increase since 1970, with acceleration from 2015, and the Chato Glacier, as other regional cirque glaciers, has undergone a rapid ice front retreat. A detailed mapping of the proglacial area of the Chato Glacier allowed the identification of a landform assemblage related to the glacier retreat during the last decades. In this paper morphological and sedimentological features of this peculiar landform assemblage, generated in an intense glacial ablation environment, are described and the causes of their origin are discussed. Among the most remarkable landforms annual moraines, hummocky moraines, esker-like landforms, flutes, kettle ponds, dirt cones, glacifluvial deposits, pronival ramparts and collapsed moraines are found. The multitemporal analysis of the Chato Glacier retreat allowed us to interpret that most of these landforms were generated when the landscape became ice-free after 2005. The Chato Glacier cirque floor gentle slope, the thin-ice thickness and the occurrence of a rocky threshold near the glacier front would have promoted the rapid glacier thinning and the disconnection of dead ice. This context, together with the sediments and meltwater availability, would have favored the development of this landform assemblage which is ephemeral due to its high susceptibility to erosion. • Proglacial landforms developed since the final Little Ice Age in a glacial cirque. • Multitemporal glacier retreat analysis and landforms associated. • Temperature increase and glacier retreat acceleration in Fuegian Andes since 1970. • Ephemeral landforms due to poor consolidation, intense meltwater and precipitation. • Satellite images and a photomosaic derived from unmanned aerial vehicle (UAV). [ABSTRACT FROM AUTHOR]