Marcos Valcárcel

University of Santiago de Compostela | USC · Department of Geography

La Serra dos Ancares es un espacio natural afectado por los procesos glaciales del Cuaternario, y que presenta fuertes pendientes en sus laderas. Se describen hasta 28 movimientos de masas en todo el sector estudiado. Los deslizamientos existentes se habían considerado mayoritariamente como de origen natural. Los datos indican que un número signifi...

The high Galician mountains are located on the border between eastern Galicia, western Asturias, and Castilla y León provinces. Their altitudes range from 1639 m (in the Serra do Courel) to 2117 m (in the Macizo de Trevinca). All these mountains are characterized by significant glacier development during the last glacial cycle at least, as evidence...

Glaciers in very low mountains near the coast, with peaks of c. 950 m, have been described in Northwestern Iberia. The high precipitation in these mountains facilitated the formation of glaciers during the Pleistocene. In the first phase, the important contribution of snow determined the existence of small ice fields in these mountains; later, very...

The only glaciers existing today in the Iberian Peninsula are small features located in the Pyrenees, though their number and extension has undergone significant changes over the Late Quaternary. The wide range of glacial landforms and deposits distributed across different Iberian ranges suggests the occurrence of several past periods with larger g...

The northwest region of the Iberian Peninsula is home to a unique ecosystem of bogs, which are particularly sensitive to projected climate change. In this context, the rate of carbon (C) accumulation in Chao de Veiga Mol, an intact raised bog, was analysed. Changes in the accumulation rate over the past 10 millennia were determined in a peat core o...

The relatively warm climate conditions prevailing today in the Mediterranean region limit cold geomorphological processes only to the highest mountain environments. However, climate variability during the Late Pleistocene and Holocene has led to significant spatio-temporal variations of the glacial and periglacial domain in these mountains, includi...

Any mountain environment has hard conditions for human being’s habitation. To achieve this, you have to survive the mountain, adapt, take advantage of its advantages and minimize its disadvantages. Nevertheless, there are settlements in these environments that have been in the same location for ages. Piornedo is an example of these mountain settlem...

On the Pico Cuiña cirque, Sierra de Ancares (León, Spain), the seasonal snow cover undergoes both slow and rapid mass displacements. Push associated with moving snow is responsible for an intense geomorphological activity, which is characterised by the plucking and transport of fragments of the bedrock, the abrasion of rock surfaces and the deposit...

In the present study we reviewed the genesis, development and classification of peatlands in the Iberian Peninsula by conducting chronostratigraphic analysis of 108 of these ecosystems. The findings are summarised as follows: 1. The region has a wide variety of peatlands which are classified according to their biogeochemical, geomorphological and e...

Se presenta un estudio etnoarqueológico sobre una alzada, hábitat estacional de la alta montaña lucense, vinculado con la actividad pastoril estival, y en menor medida con la agrícola para, de acuerdo con los datos obtenidos a través del trabajo de campo antropo-lógico y geográfico, establecer un modelo explicativo del proceso de abandono casi tota...

En el presente trabajo se cita la presencia en distintos macizos del NW de la Península Ibérica de formas de erosión glaciar descritas como «formas glaciares en cuña». Este tipo de formas se describen en la bibliografía como vinculada a glaciares activos, y se consideran indicadoras de la presencia de glaciarismo de base fría. Estas condiciones ind...

Abstract (The periglaciation of the Iberian Peninsula): Mountain environments in the Iberian Peninsula were heavily glaciated during the Last Glaciation. However, glaciers were mostly confined within the mountain valleys. Lower areas as well as the highest lands where topography did not favour ice accumulation were affected by intense periglacial p...

Active periglacial processes are currently marginal in the Iberian Peninsula, spatially limited to the highest mountain ranges. However, a wide variety of periglacial deposits and landforms is distributed in low- and mid-altitude environments, which shows evidence of past periods with enhanced periglacial activity. The purpose of the present resear...

El análisis del comportamiento de la temperatura y humedad edáfica in situ de las turberas del norte de Galicia en una serie temporal larga revela que los mecanismos de emisión atmosférica de CO2 y CH4 desde estos suelos orgánicos podrían estar parcialmente bloqueados, y que estos suelos todavía funcionan como sumideros netos de C en las condicione...

SANTIAGO DE COMPOSTELA 24 – 27 de octubre 2012 PRESENTACIÓN La complejidad e incertidumbre del mundo actual es uno de los hechos más característicos que nos acompaña y angustia en el segundo decenio del siglo XXI. A los complejos entramados de intereses comunes y de conflictos entre poderes económicos y políticos, poderes fácticos y reales, region...

In this paper we synthesize the research in glacial geomorphology and geochronology in northern Spain, with special attention to the evidence of local glacier maximum extent earlier than the global LGM of MIS 2 (18-21 ka BP). More accurate models of glacier evolution have been defined based on limnogeological, geochronological and geomorphological...

Sediments at Pias (Galicia) provide evidence of Upper Pleistocene glacial activities at a valley junction in the north-western mountains of Spain. The sedimentary sequence consists of lower, predominately fine-grained lacustrine deposits with few lonestones, overlain by poorly sorted, sandy gravels interstratified with massive diamicton deposited d...

The geomophic action of the seasonal snow cover on the northeastern slope of Pico Cuiña (Sierra de Ancares, León province), is described. Mass movement of the snow is responsible for the quarrying of bedrock and the transport of loose clasts to the lower margins of the slope. Such geomorphic activity gives rise to a set of characteristic geoforms s...

The durometer is a hardness tester developed to measure hardness of metallic materials that has been recently introduced to measure rock hardness in weathering studies. Aoki & Matsukura (2007) highlight some advantages of the durometer compared with the Schmidt Rock Test Hammer: the smaller plunge allows measurements in small surfaces such as taffo...

Seasonal snow cover attains significant thickness and duration on the rock slopes of the Cuiña Cirque, Sierra de Ancares, Northwestern Spain (latitude 42°50' N; longitude 6°49' W; 1.860 m.a.s.l.). The basal displacement of the snow cover is responsible for an intense geomorphological activity comprising detachment of bedrock fragments, transport of...

The geomophic action of the seasonal snow cover on the northeastern slope of Pico Cuina (Sierra de Ancares, Leon province), is described. Mass movement of the snow is responsible for the quarrying of bedrock and the transport of loose clasts to the lower margins of the slope. Such geomorphic activity gives rise to a set of characteristic geoforms s...

Studies carried out since 2004 in the "Andes Fueguinos" (Tierra del Fuego, Argentina) demonstrate the great importance that cryogenic processes have at the present time. The current investigations are based on two directions of research: (1) the mapping of the existing cryonival forms, and (2) the measurement of their activity. First, the existing...

The morphodynamics of paraglacial coastal systems is controlled by a number of factors, including rock basement structure, sediment disposal, changes in the relative sea-level and wave regime. Of great importance is the thickness and the particle size composition of the glacial deposits because they are not only the main source of material, but als...

Seasonal, late-lying snow cover is an active geomorphic agent at high elevations in the Ancares Sierra, northwestern Spain (lat. 42°50'N, long. 6°49'W). Movements of the snow cover are frequent and are thought to be mainly due to a combination of snowcreep and subnival sliding. Snowslide erosion is characterized by plucking of bedrock fragments; cl...

The sclerometer or Schmidt Rock Test Hammer has been broadly applied in geomorphology to estimate the strength of different rock types and to measure the degree of rock weathering. It has been proved that for a rock type, the rebound values are lower in weathered than in fresh rock surfaces. This evidence suggests that if there is any factor that c...

The push effect associated with the movement of a snow cover has been identified as a major process in the origin of subnival geoforms, including small pronival ramparts. In this contribution we present the results of a geomorphological survey carried out in the central sector of the backwall of the Cuiña Cirque, Ancares Sierra, northwestern Spain...

Processes in rocky coasts operates in a wide range of time-scales, from seconds to millennia, but sealeveloscillations probably are the most significant changes. A portion of land changes from coastal tocontinental environment as sea-level rise or fall, and, although a re-occupied coast is never the same, itcan conserve a memory of the previous mor...

The Schmidt Rock Test Hammer was used to study the effect of abrasion on shore platforms in Galicia, northwestern Spain. On platforms where tidally-induced weathering (salt, wetting and drying, etc.) is dominant, rock strength is significantly lower than in areas where abrasion is, or has been active in the recent past. This suggests that abrasion...

A preliminary survey of periglacial landforms found in the Monte Alvear region of the Fuegian Andes, subantarctic Argentina has revealed the presence of nivation hollows, subnival ‘boulder’ (clast) pavements, protalus ramparts, debris lobes, patterned ground and cryo-ejected clasts. With the exception of debris lobes and cryo-ejected clasts, all th...

Abrasion is one of the less known processes operating on rocky coasts. This work tries to show some of the basic mechanisms in this type of processes, namely in coarse-grained beaches. The two main factors in the abrasive processes are the balance wave energy and clast size, but in areas in which the existence of thick periglacial and fluvio-nival...

p>En valle de Balouta ha sido estudiado con anterioridad por LLOPIS LLADÓ (1954) y por nosotros (PÉREZ ALBERTI ET AL., 1993). En este último trabajo se citaba la presencia de un afloramiento de materiales de origen glaciar en las cercanías del pueblo de Murias, a unos 780 m de altitud, después de atravesar un sector del valle muy encajado de unos 6...

Glacial forms and deposits founded in the valleys of Procarizas and Valongo (eastern slope of Serra dos Ancares, Western Cordillera Cantabrica) are described and mapped in this work. Even frontal dump moraines no were founded, a reconstruction of glacial tongues at maximum stage could be make taken into account some sedimentary and geomorphologic e...

There are many glacial features in the northern slope of the Airibio Range (Galician Serras Orientais, NW Iberian Peninsula) wich has its top al Poza do Acelo (1.465 m). In this chapter, some deposits and forms located at Queixadoiro Valley are described and mapped in detail. Three complexes of latero-frontal dump moraines enclose a short fossil gl...

Characteristic geomorphological glacial features found in the valley of A Seara (Serra do Courel, NW Iberian Peninsula) are described. The main erosive forms are circus and rock erosion thresholds; morainic deposits and till outcrops are common sedimentary forms and deposits. The distribution of fronto-lateral dump moraines let us to define two sta...

The Sierra of Ancares, sited in the NW of the Iberian Peninsula, is the boundary between Galicia, Asturias and León. It si characterized bay a topography of deep valleys and genty ridges, resulting from the strong action of rivers in the Sil and ANvia headwaters. Notable glacial and periglacial features have take place in Ancares. This paper analyz...

The east valleys of Sierra de Ancares (NW Iberia) have been affected by the last glacial period. In this paper we describe many forms and deposits of three glacial complexes. The main ice sheets reached up to 13 Km. long and 280 m. depth. The location of deposits allow us to define three glacial stages in this part of the Cantabrian range.

RESUMEN. A partir del estudio etnológico de los hábitats estacionales de montaña en la Sierra de Ancares, en el Noroeste de la Península Ibérica, y de las características ambientales en el que se encuentran se elabora un modelo interpretativo sobre la estacionalidad de las ocupacio-nes como una respuesta adaptativa a las condiciones climáticas. ABS...

Resúmen: Trabajos recientes han demostrado que, en plataformas litológicamente homogéneas, el esclerómetro puede registrar cambios en la resistencia de la superficie de la roca en función de la alteración mareal, de forma que, en ausencia de procesos de erosión mecánica, fundamentalmente de abrasión, la alteración tiende a incrementarse hacia las c...