Tracing the boundaries of Cenozoic volcanic edifices from Sardinia (Italy): a geomorphometric contribution

Abstract

Abstract. Unequivocal delimitation of landforms is an important issue for different purposes, from sciencedriven morphometric analysis to legal issues related to land conservation. This study is aimed at giving a new contribution to the morphometric approach for the delineation of the boundaries of volcanic edifices, applied to 13 monogenetic volcanoes (scoria cones) related to the Pliocene-Pleistocene volcanic cycle in Sardinia (Italy). External boundary delimitation of the edifices is discussed based on an integrated methodology using automatic elaboration of digital elevation models together with geomorphological and geological observations. Different elaborations of surface slope and profile curvature have been proposed and discussed; among them, two algorithms based on simple mathematical functions combining slope and profile curvature well fit the requirements of this study. One of theses algorithms is a modification of a function introduced by Grosse et al. (2011), which better performs for recognizing and tracing the boundary between the volcanic scoria cone and its basement. Although the geological constraints still drive the final decision, the proposed method improves the existing tools for a semi-automatic tracing of the boundaries.

Detection and Description of Sand Dunes Using a Geomorphometric Approach

“…For instance, algorithms for the extraction of drainage networks and the associated catchment areas are typical of this method type. Such algorithms have already been designed to detect specific landform other than dunes and this is the case for volcanoes 20 . Their delineation relies on the fact the edifice base almost systematically coincide with areas of gently slope and maximum of concavity.…”

Calibrating fluvial erosion laws and quantifying river response to faulting in Sardinia, Italy

“…We interpreted faults and volcanic eruption centres using satellite imagery, topography, the 1:100,000 scale geological map (Servizio dell 'Attivià Mineraria, 1988), and topographic gradient derived from a digital elevation model (Figure 2). We assumed that all faults are relatively steeply dipping features exhibiting abrupt breaks in slope at the base of the fault scarp, and that eruption centres have approximately circular planform geometries and higher elevations than the surrounding outcrop (Melis et al, 2014).…”

New Morphometric Data of Lunar Sinuous Rilles

“…Automatic extraction of landforms is a well-known methodology to obtain quantitative data from DEM and spectral imagery in geological and planetary studies [33], [34], [35], [36]. Morphometric variables are widely used in geomorphic research supporting models of evolution of landforms [37], [38]. Studying the sinuous rilles, two main characteristics of these features have to be considered: i) the variability of the shape of these morphologies; ii) the spatial resolution of the available data.…”