Investigating the Correlation of Tectonic and Morphometric Characteristics with the Hydrological Response in a Greek River Catchment Using Earth Observation and Geospatial Analysis Techniques

Abstract

Morphometric analysis can be used to investigate catchment dynamics and tectonic processes responsible for the development of drainage catchments and to support flood risk assessment. In this study, a comparative GIS-based morphometric analysis between the main southern and northern sub-catchments of the Sperchios River basin, Central Greece, was performed, using geospatial and remote sensing data. The goal was to investigate their correlation with the peculiar geotectonic activity and the frequent flash-flood events that occur in the river floodplain. All sub-catchments characteristics are linked with the geological formation types of the area, in combination with ongoing tectonic activity. The results indicate that drainage network development is significantly controlled by the region’s overall tectonic activity. The morphometric characteristics—i.e., bifurcation ratio, drainage density, circularity ratio, elongation ratio and water concentration–time values, reflect the flood-prone character of the southern part of Sperchios River catchment in comparison to the northern part, especially during intense rainfall events. The study can provide valuable insight into identifying how morphometric characteristics are associated with increased flood hazard.

Long and Short-Term Coastal Changes Assessment Using Earth Observation Data and GIS Analysis: The Case of Sperchios River Delta

“…The basin is a graben-like asymmetrical depression as a part of a tectonic trough, controlled by major NW-SE and E-W trending faults parallel to the Atalanti normal fault zone [46,47]. The tectonic activity of this graben separates the catchment into a northern and a southern part, according to the theory of tectonic dipoles [48], with the latter being lifted and the former sinking [49,50]. The northern part is characterized by mild relief and lower mean elevation, and the southern displays strong relief, steep slopes, and diverse topographic features.…”

“…Local tectonic movements and river sedimentation processes play the most important role in the coastal area development, mostly due to periodical flood flows and less to erosion caused by sea currents or sea-level changes [42,49,80,81]. The basin has undergone several serious earthquakes and flood events throughout the last couple of millenniums [43,48,50,82]. Flood events occur frequently due to the geomorphological characteristics of the basin (very mountainous and with steep slopes, especially at its southern part) and the coastal part (intense meandering and very gentle slopes) [43,48].…”

“…The basin has undergone several serious earthquakes and flood events throughout the last couple of millenniums [43,48,50,82]. Flood events occur frequently due to the geomorphological characteristics of the basin (very mountainous and with steep slopes, especially at its southern part) and the coastal part (intense meandering and very gentle slopes) [43,48]. The most significant ones were those of 1889, 1939, 1954, 1984, 1987, 1994, 1997, 2001, 2003, 2012, and 2015, in response primarily to sudden rainstorms or snowmelt, covering usually areas from roughly 20,000 to 100,000 ha [44,59].…”

“…Today the Sperchios river is in a stage of maturity, while some tributary rivers at the basin's southern part, such as the Gorgopotamos and the Assopos, are still in the youth stage. In such conditions, the accretion or erosion of the coastline is principally due to the neotectonic activity, the sedimentation processes, climate change, and the direct and indirect human actions at the coastal area [48,87].…”

Morphoneotectonics of the Abruzzo Periadriatic Area (Central Italy): Morphometric Analysis and Morphological Evidence of Tectonics Features

“…The Relief Ratio (Rh) is the measure of the overall gradient aspects of a given catchment [133][134][135]. It is estimated using the following equation:…”