Evaluating Characteristics of an Active Coastal Spreading Area Combining Geophysical Data with Satellite, Aerial, and Unmanned Aerial Vehicles Images

Emanuele Colica; Luciano Galone; Sebastiano D’Amico; Adam Gauci; Roberto Iannucci; Salvatore Martino; Davide Pistillo; Peter Iregbeyen; Gianluca Valentino

doi:10.3390/rs15051465

Remote Sensing (Mar 2023)

Evaluating Characteristics of an Active Coastal Spreading Area Combining Geophysical Data with Satellite, Aerial, and Unmanned Aerial Vehicles Images

Emanuele Colica,
Luciano Galone,
Sebastiano D’Amico,
Adam Gauci,
Roberto Iannucci,
Salvatore Martino,
Davide Pistillo,
Peter Iregbeyen,
Gianluca Valentino

Affiliations

Emanuele Colica: Department of Geosciences, University of Malta, MSD2080 Msida, Malta
Luciano Galone: Department of Geosciences, University of Malta, MSD2080 Msida, Malta
Sebastiano D’Amico: Department of Geosciences, University of Malta, MSD2080 Msida, Malta
Adam Gauci: Department of Geosciences, University of Malta, MSD2080 Msida, Malta
Roberto Iannucci: Dipartimento di Scienze della Terra e Centro di Ricerca per i Rischi Geologici CERI, University of Rome “La Sapienza”, 000100 Rome, Italy
Salvatore Martino: Dipartimento di Scienze della Terra e Centro di Ricerca per i Rischi Geologici CERI, University of Rome “La Sapienza”, 000100 Rome, Italy
Davide Pistillo: Dipartimento di Scienze della Terra e Centro di Ricerca per i Rischi Geologici CERI, University of Rome “La Sapienza”, 000100 Rome, Italy
Peter Iregbeyen: Department of Geosciences, University of Malta, MSD2080 Msida, Malta
Gianluca Valentino: Department of Communications & Computer Engineering, Faculty of Information and Communication Technology, University of Malta, MSD2080 Msida, Malta

DOI: https://doi.org/10.3390/rs15051465
Journal volume & issue: Vol. 15, no. 5
p. 1465

Abstract

Read online

The northern region of the Maltese archipelago is experiencing lateral spreading landslide processes. This region is characterized by cliffs with a hard coralline limestone outcropping layer sitting on a thick layer of clay. Such a geological configuration causes coastal instability that results in lateral spreading which predispose to rockfalls and topplings all over the cliff slopes. The aim of this research was to develop a methodology for evaluating cliff erosion/retreat using the integration of geomatics and geophysical techniques. Starting from a 3D digital model of the Selmun promontory, generated by unmanned aerial vehicle (UAV) photogrammetry, it was possible to map the fractures and conduct geophysical measurements such as electrical resistivity tomography and ground penetrating radar for the identification and mapping of vertical fractures affecting the hard coralline limestone plateau, and to create a 3D geological model of the study area. In addition to this, high-accuracy orthophotos from UAV that were captured between 1957 and 2021 were georeferenced into a GIS and compared to aerial and satellite images. The movement and evolution of boulders and cracks in rocks were then vectorized to highlight, track and quantify the phenomenon through time. The results were used to derive a qualitative assessment of the coastal variations in the geometric properties of the exposed discontinuity surfaces to evaluate the volumes and the stop points of the observed rockfalls. The outcomes of this research were finally imported in a GIS which offers an easy approach for the collection and processing of coastal monitoring data. In principle, such a system could help local authorities to address social, economic and environmental issues of pressing importance as well as facilitate effective planning in view of a risk mitigation strategy.

Published in Remote Sensing

ISSN: 2072-4292 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Science
Website: http://www.mdpi.com/journal/remotesensing/

About the journal

Abstract

Keywords