DTM-Based Morphometric Analysis of Scoria Cones of the Chaîne des Puys (France)—The Classic and a New Approach

Fanni Vörös,Dávid Karátson,Benjamin Van Wyk De Vries,Balázs Székely

doi:10.3390/rs13101983

Abstract

Scoria cones are favorite targets of morphometric research. However, in-depth, DTM-based studies have appeared only recently, and new methods are being developed. This study provides a classic evaluation of the cones of Chaîne des Puys (Auvergne, France) as well as introduces a more detailed and statistics-based set of properties. Beside the classic parameters, a sectorial approach is applied to the slope distributions calculated from high resolution DTMs for 25 cones of different lithologies, in order to study the various (a)symmetries of the cones. DTM-based morphometric characteristics have been found to be different from classic descriptors, whereas the sectorial approach describes correctly the more and the less regular shapes. The distribution of interquartile ranges of the sectorial slope distributions is skewed. Sectorization discriminates various types of symmetries: there are almost circular cones, but the majority are elongated and have some asymmetry. The relationship between size parameters reflects the lithology, rather than the age of the cone. The attempt to relate morphometric parameters to age data is only partially successful: although there is a certain trend, within the same lithological group, subtle but possibly systematic trends can be detected for decreasing morphometric values (e.g., slope) with the age. The regression models indicate various outcomes. Further work is needed to understand all the diverse parameters, especially the lithology–shape relationship, and how symmetry is connected to different factors.

Highlights

Since the beginning of the 2000s, with the appearance of increasingly better resolution digital terrain models (DTMs), they have played a role as a background and illustration but have become increasingly common in various geomorphometric studies.On the one hand, in many cases, the Digital terrain models (DTM)-derived data are more accurate and detailed than the older data obtained from field measurements and based on stereophotogrammetry.In the field, for example, the vegetation can obscure microtopographic elements, which can be seen on the finer DTM
Settle [19] used a height of the cone (Hco) = 0.2 Wco reference line that characterizes the initial shape of cinder cones formed in both types of volcanic provinces prior to erosive degradation
The order of the scoria cones is as follows: we examined the results obtained with the two types of calculations and arranged them in ascending order according to their differences

Summary

Introduction

Since the beginning of the 2000s, with the appearance of increasingly better resolution digital terrain models (DTMs), they have played a role as a background and illustration but have become increasingly common in various geomorphometric studies.On the one hand, in many cases, the DTM-derived data are more accurate and detailed than the older data obtained from field measurements and based on stereophotogrammetry.In the field, for example, the vegetation can obscure microtopographic elements, which can be seen on the finer DTM. Since the beginning of the 2000s, with the appearance of increasingly better resolution digital terrain models (DTMs), they have played a role as a background and illustration but have become increasingly common in various geomorphometric studies. In many cases, the DTM-derived data are more accurate and detailed than the older data obtained from field measurements and based on stereophotogrammetry. It is perfectly suitable for the study of large groups and geomorphological forms (e.g., [1]). We examined one of the simplest volcanic structures, the scoria cone, from a geomorphometric point of view. Because they are monogenetic forms, they are perfectly suited to study degradation. Following Porter [2], Wood [3,4], and many other researchers (see previous research), we investigated this degradation in the Chaîne des Puys with different parameters and supplemented them with calculations of scoria cone asymmetry

Methods

Results

Conclusion