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A total of 156 glacial cirques located on two different areas in the Cantabrian Mountains (NW Spain) were identified and measured in order to continue and expand the study of these large-scale erosional forms in European mountains. Environmental variables that may explain cirque distribution (altitude, aspect and lithology), and their most important morphometric features (area, length (L), width (W), headwall height (H), and L/W, L/H and W/H indices), are analysed. Statistical analysis has been applied as indicators of contrast (ANOVA) and association (correlation and regression). Conglomerate analysis (CLUSTER) has been used to discriminate cirque groups based on their morphometric variables. Results show that cirques occur at lower altitudes in the Upper Sil River basin area than in the Montaña Central area due to a lower former equilibrium line altitude (ELA) position. In the Upper Sil River basin, environmental variables appear to have had a strong influence on the location and size of cirques: the largest cirques are located in quartzite rocks at elevations above 2000 m and face N or NE. In Montaña Central, the influence of these factors was more limited as a consequence of higher geological structure control. Cirque sizes generally are modest compared with cirques present in other mountain ranges globally, most likely due to shorter glacial occupancy in the Cantabrian Mountains. [ABSTRACT FROM AUTHOR]

Abstract: Several glaciers developed in the Cantabrian Mountains (NW Spain) during the last glacial maximum (LGM). In the last 15years, several studies of glacial geomorphology have increased the knowledge about the limits of the glaciation, but little data are available about many valleys, especially on the northern slope, due to extensive postglacial erosion. In this study, we apply the AABR method to reconstruct palaeo-equilibrium-line altitudes (ELAs) in eleven palaeo-glaciers that are considered to be representative of the different areas of the range. To reduce the ambiguity in the palaeo-ELA values caused by local factors, we analysed medium and large glaciers (4.7 to 65.5km2) except for the Sil complex glacier, which was the largest glacier in northwestern Spain (445km2). The palaeo-ELAs during the local LGM ranged between 1000 and 2000m and had a similar pattern to the present-day winter precipitation and summer temperatures. [Copyright &y& Elsevier]