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Coastal environments are highly recognized for their spectacular morphological features and economic activities, such as agriculture, maritime traffic, fishing, and tourism. In the context of climate change and the evolution of physical processes, the occurrence of intense natural phenomena adjacent to populated coastal areas may result in natural hazards, causing human and/or structural losses. As an outcome, scientific interest in researching and assessing multi-hazard susceptibility techniques has increased rapidly in an effort to better understand spatial patterns that are threatening coastal exposed elements, with or without temporal coincidence. The islands of Milos and Thira (Santorini Island) in Greece are prone to natural hazards due to their unique volcano-tectonic setting, the high number of tourist visits annually, and the unplanned expansion of urban fabric within the boundaries of the low-lying coastal zone. The main goal of this research is to analyze the onshore coastal terrain’s susceptibility to natural hazards, identifying regions that are vulnerable to soil erosion, torrential flooding, landslides and tsunamis. Therefore, the objective of this work is the development of a multi-hazard approach to the South Aegean Volcanic Arc (SAVA) islands, integrating them into a superimposed susceptibility map utilizing Multi-Criteria Decision-Making (MCDM) analysis. The illustrated geospatial workflow introduces a promising multi-hazard tool that can be implemented in low-lying coastal regions globally, regardless of their morphometric and manmade characteristics. Consequently, findings indicated that more than 30% of built-up areas, 20% of the transportation network, and 50% of seaports are within the high and very high susceptible zones, in terms of the Extended Low Elevation Coastal Zone (ELECZ). Coastal managers and decision-makers must develop a strategic plan in order to minimize potential economic and natural losses, private property damage, and tourism infrastructure degradation from potential inundation and erosion occurrences, which are likely to increase in the foreseeable future.

Coastal environments are highly recognized for their spectacular morphological features and economic activities, such as agriculture, maritime traffic, fishing, and tourism. In the context of climate change and the evolution of physical processes, the occurrence of intense natural phenomena adjacent to populated coastal areas may result in natural hazards, causing human and/or structural losses. As an outcome, scientific interest in researching and assessing multi-hazard susceptibility techniques has increased rapidly in an effort to better understand spatial patterns that are threatening coastal exposed elements, with or without temporal coincidence. The islands of Milos and Thira (Santorini Island) in Greece are prone to natural hazards due to their unique volcano-tectonic setting, the high number of tourist visits annually, and the unplanned expansion of urban fabric within the boundaries of the low-lying coastal zone. The main goal of this research is to analyze the onshore coastal terrain's susceptibility to natural hazards, identifying regions that are vulnerable to soil erosion, torrential flooding, landslides and tsunamis. Therefore, the objective of this work is the development of a multi-hazard approach to the South Aegean Volcanic Arc (SAVA) islands, integrating them into a superimposed susceptibility map utilizing Multi-Criteria Decision-Making (MCDM) analysis. The illustrated geospatial workflow introduces a promising multi-hazard tool that can be implemented in low-lying coastal regions globally, regardless of their morphometric and manmade characteristics. Consequently, findings indicated that more than 30% of built-up areas, 20% of the transportation network, and 50% of seaports are within the high and very high susceptible zones, in terms of the Extended Low Elevation Coastal Zone (ELECZ). Coastal managers and decision-makers must develop a strategic plan in order to minimize potential economic and natural losses, private property damage, and tourism infrastructure degradation from potential inundation and erosion occurrences, which are likely to increase in the foreseeable future. [ABSTRACT FROM AUTHOR]

The Late Miocene igneous rocks of the Bodrum magmatic complex (SW Anatolia, Turkey), are composed of small monzonitic intrusions and trachyandesite-trachydacite volcanic rocks. The Kadıkalesi monzonite (KM) forms a small stock (<1 km2) made of plagioclase, biotite, hornblende, clinopyroxene, and quartz, and geochemically belongs to high-K calc-alkaline to shoshonitic, metaluminous series. The zircon separates from the KM yielded 9.5 ± 0.15 Ma core and 8.6 ± 0.04 Ma rim ages, revealing that emplacement of the monzonite continued up to ~8 Ma. The geochemical and mineralogical evidence suggests that the KM was derived by extensive fractionation of plagioclase, alkali feldspar, apatite, and clinopyroxene and/or Fe-Ti oxides and mixing of differently evolved melts. The monzonite has 760–866 Ma depleted mantle Nd Model ages which are considerably younger than the Cycladic and Menderes Massif plutons, as well as the other Miocene magmatic rocks from western Anatolia. On the basis of geochronological and geochemical features, we propose that the KM was fractionated from mafic melts derived from partial melting of spinel-facies (shallow depth) and crustally-contaminated (metasomatized/orogenic) asthenospheric mantle. Asthenospheric input were likely supplied from the slab window between the Aegean and Cyprian slabs, and likely contaminated by subducted sediments from the Aegean slab. It is also suggested that the current geodynamic setting of the Aegean region is also applicable to the Middle Miocene, meaning that the magmatic activity of the SAVA likely commenced at ~10 Ma, earlier than previously considered. [ABSTRACT FROM AUTHOR]

Background:The South Aegean Volcanic Arc (SAVA), one of the most notable geological structures of the Mediterranean Sea, is floristically well known. Nevertheless, the factors that contribute to shaping the plant species richness of the SAVA remain unclear. Aims:To investigate the factors that affect plant species richness and identify plant diversity hotspots in the SAVA and other central Aegean islands. Methods:We used stepwise multiple regression to test the relationship between a number of environmental factors and plant species richness in the SAVA, as well as the residuals from the species–area linear regressions of native, Greek and Cycladian endemic taxa as indicators of relative species richness. Results:The area was confirmed to be the most powerful single explanatory variable of island species richness, while geodiversity, maximum elevation and mean annual precipitation explained a large proportion of variance for almost all the species richness measures. Anafi, Amorgos and Folegandros were found to be endemic plant diversity hotspots. Conclusions:We have demonstrated that geodiversity is an important factor in shaping plant species diversity in the Cyclades, while mean annual precipitation, human population density and maximum elevation were significant predictors of the Greek endemics present in the Cyclades. Finally, Anafi was found to be a plant diversity hotspot in the South Aegean Sea. [ABSTRACT FROM AUTHOR]

The Methana Peninsula (Saronic Gulf, Greece) constitutes the youngest and northwestern part of the South Aegean Volcanic Arc. The flora of the Methana Peninsula consists of 620 taxa, 101 of which are under some protection status, while 35 are Greek endemics and 380 are reported here for the first time. The study area has the highest percentage of endemism in the Saronic Gulf. Additionally, for some endemic taxa, their known distribution is expanded. These include Crocus sieberi subsp. atticus and Ophrys oestrifera subsp. leptomera, reported for the first time for the phytogeographical region of the Peloponnese; Campanula andrewsii subsp. hirsutula and Colchicum psaridis, reported for the first time for the North Peloponnese; and Trigonella rechingeri, reported for the first time from the Greek mainland. The floristic affinities between the study area and the large islands of the Saronic Gulf are examined by the application of Sørensen’s index to investigate the relationships between them. [ABSTRACT FROM PUBLISHER]

Abstract: An extensive geochemical survey of the fluids released by the volcanic/geothermal system of Methana was undertaken. Gases were characterized based on the chemical and isotopic [helium (He) and carbon (C)] analysis of 27 samples. Carbon dioxide soil gas concentration and fluxes were measured at 179 sampling sites throughout the peninsula. Forty samples of thermal and cold groundwaters were also sampled and analysed to characterize the geochemistry of the aquifers. Gases of hydrothermal origin gave a preliminary geothermometric estimate of about 210 °C. The He-isotope composition indicated mantle contributions of up to 40%, and the C-isotope composition of CO2 indicated that it predominantly (>90%) originated from limestone decomposition. The groundwater composition was suggestive of mixing between meteoric and hydrothermally modified sea-water endmembers and water–rock interaction processes limited to simple rock dissolution driven by an increased endogenous CO2 content. All of the thermal manifestations and anomalous degassing areas, although of limited extent, were spatially correlated with the main active tectonic system of the area. The total CO2 output of the volcanic system has been preliminary estimated to be less than 0.05 kg s−1. Although this value is very low compared to those of other volcanic systems, anomalous CO2 degassing at Methana – which is currently restricted to limited areas and at present is the only volcanic risk of the peninsula – is a potential gas hazard that warrants further assessment in future studies. [Copyright &y& Elsevier]