Coastline evolution is a proxy of coastal erosion, defined as the wasting of land along the shoreline due to a combination of natural and/or human causes. For countries with a sea border, where a significant proportion of the population lives in coastal areas, shoreline retreat has become a very serious global problem. Remote sensing data and photogrammetry have been used in coastal erosion mapping for many decades. In the current study, multi-date analogue aerial photos, digital aerial photos, and declassified satellite imagery provided by the U.S. Geological Survey (USGS), Pleiades satellite data, and unmanned aerial vehicle images were combined for accurate mapping of the southwestern Lefkada (Ionian Sea, Greece) coastline over the last 73 years. Different photogrammetric techniques were used for the orthorectifation of the remote sensing data, and geographical information systems were used in order to calculate the rates of shoreline change. The results indicated that the southwest shoreline of Lefkada Island is under dynamic equilibrium. This equilibrium is strongly controlled by geological parameters, such as subsidence of the studied shoreline during co-seismic deformation and mass wasting. The maximum accretion rate was calculated at 0.55 m per year, while the respective erosion rate reached −1.53 m per year.

On 3 March 2021, a strong shallow earthquake affected northern Thessaly, Greece, with an epicenter close to Damasi village causing significant destruction of many stone houses. In this contribution, we provide fieldwork observations, satellite radar interferometry, mapping of the active faults exposed in the epicentral area, liquefactions and coseismic surface ruptures, and preliminary geomorphological analyses of the epicentral area. The geomorphological analysis is based on air photographs, digital surface models analysis, Real-Time Kinematik (RTK) measurements with Global Navigation Satellite System (GNSS) receivers, and data from UAV flight campaigns. Although the seismotectonic setting of the area is complex and there is an apparent mismatch between field and interferometric data, the results of our investigations suggest that at least three fault segments were reactivated by the major shocks of the March seismic sequence. These tectonic structureslikely represent the westward propagation of the Tyrnavos Graben, where newly formed and inherited low-angle faults interplay in a complex manner.

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Morphotectonic analysis using geomorphic indices has been developed as a basic reconnais sance tool in order to identify areas experiencing rapid tectonic deformation or estimate relative variations of tectonic activity in a specific area. We applied this analysis in Eliki fault zone, which is located in the western part of the Gulf of Corinth. Eliki fault zone was selected because it displays a spectacular geomorphic expression and hosts historic and recent seismicity. The intensity of active tectonics is interpreted through a detailed geomorphic study of the fault-generated mountain fronts and fluvial systems. Tectonic geomorphology analysis of the Eliki footwall area includes the applica tion of the most commonly used geomorphic indices, such as the mountain front sinuosity index (Smf), the valley floor / width ratio index (Vf), the stream gradient index (SL) and the transverse to pographic symmetry factor (T). These indices were estimated on topographic maps and aerial pho tographs of the study area in order to correlate active tectonics and erosional processes. Our re sults imply that the Eliki fault zone can be assigned to a tectonic class of the higher tectonic activity. However, spatial variations of tectonic activity along the segmented studied fronts point to a general trend of increasing activity towards the east, which is gradually decreasing towards the west.