Erosion Surface and Granitic Morphology in the Sierra de Lihuel Calel, Province of La Pampa, Argentina

Abstract

This chapter aims to characterize the landforms of the ignimbrite landscape in the Sierra de Lihuel Calel, province of La Pampa, Argentina. DEM data from SRTM were used for the analysis of morphometric characteristics and other parameters, so as to obtain longitudinal profiles and identify the boundaries of the paleosurface. By means of the interpretation of satellite imagery and field observations, the different features of this ancient landscape were identified as well as the lithology and fabric of the volcanic and pyroclastic rocks, which were petrographically studied. Textural transformations occurring in ignimbrites provided properties to these rocks which are similar to those common in granitic rocks. The studied landforms might be regarded as pseudo-granitic landforms, and thus major and minor landforms are described. Fracturing has been found as a significant factor in landform evolution.

Mapping microhabitat structure and connectivity on a tropical inselberg using UAV remote sensing

“…This tendency was found in P4 and P5 (Figure 2d to f). If we look at the cross-section profile for these pools (Figure 2j to l), it is shown they have a more gradual change in the slope of their sides, and their profiles resemble more a half ellipsoid, which is congruent with the pit gnamma morphology (Aguilera et al, 2014). However, P4 and P5B have a peculiar depth profile that is asymmetric, with different slopes on both sides of the pool.…”

“…Based on modeled pool shapes we classified our pools in "Pits gnamma," "Pans gnamma," and "Armchair gnamma" according to Campbell (1997), Timms (2013), Aguilera et al (2014), andTimms andRankin (2016). To analyze the shape and volume of pool P5 (dataset ID 6) we decided to subdivide it into two pools, P5A and P5B, because they have a soil bank with two big trees in the middle.…”

Patrimonio geomorfológico y geodiversidad en las Sierras de Lihué Calel (Argentina)

“…La topografía fue recubierta por una capa de sedimentos eólicos (limo, limo-arenoso y arena-limosa) hacia fines del Mioceno en la era Cenozoica. Además el proceso de peneplanización, de constante equilibrio entre la erosión y sedimentación, contribuyó a modelar el paisaje constituido por un inselberg (Sierras de Lihué Calel) rodeado de una llanura con suaves ondulaciones (Aguilera et al, 2014).…”

“…En el Parque Nacional Lihué Calel, la valorización de las sierras desde el punto de vista de la geodiversidad tiene actualmente poco desarrollo. En relación con el patrimonio geológico, Llambías y Leveratto (1975) y Linares et al (1980) realizaron los primeros estudios geológicos regionales que sentaron las bases para los trabajos de Llambias (2008) y Aguilera et al (2014). En estos se realizó la descripción geológica del sitio y la identificación de las geoformas del relieve grafítico.…”