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Sediment cores of 4m were sampled in Epanoni coastal lagoon basin in Eastern Thermaikos Gulf. Within this study, we present results of Magnetic Susceptibility (MS) measurements and sedimentological analysis (XRD and grain-size distribution) for the first meter EP1-1 aiming to contribute to the reconstruction of the paleoclimatic regime in Thermaikos Gulf during the Holocene. Based on MS and XRD, we concluded that probably a wet episode is reflected at 3760±25 BP resulting in greater material transfer with higher values of magnetic susceptibility. The increased ratio of the coarser sediments in depths 40-50cm suggests an increased run-off. Subsequently that, the presence of gypsum in the upper layers of 14-39cm depth indicates a dry period with intense evaporation.

Research has shown that fluvial systems exhibit a rapid response to extreme events, such as floods or climate-tectonic interplay, the evidence of which is recorded in fluvial sediments. This article provides new data and insights into the reconstruction of the Anthemountas River depositional environment. The study was conducted with granulometric analysis and with the lithostratigraphic and chronostratigraphic description of approximately 20000 yr B.P., the area's most extended sedimentary sequence to date. The evolution of the Anthemountas River Valley during the Late Pleistocene and Holocene is closely linked to tectonic activity and changes in the sea-level and climate. The interpretation of grain size cumulative curves, frequency curves, and the Passega C-M diagram is used in conjunction with the textural parameters of the sediments to obtain information about the means of transport and the intensity of environmental conditions. In addition, the loss on ignition method was used to estimate two parameters; organic matter and carbonates. Chronostratigraphic details were also obtained from the A.M.S. dating of charcoal samples. The analysis has identified the Late Pleistocene aggradation materials and the transition to the Holocene. Sedimentation can be described as a fluvial valley-fill sequence with periodical in-channel, off-channel, and floodplain series. After 3500 cal. B.P., the area is affected by the possible formation of a bay-head delta, with fluvial-dominated sands and the development of stable floodplains. Finally, the fluvial records of the Anthemountas River reveal phases of hydrological activity and stability.

Ancient Poliochni is one of the oldest excavated cities in the Aegean Sea and its connection with the sea is indisputable and diachronic during the city habitation from 3500/3300 BC to 2000/1900 BC. The research focuses on the palaeogeographical evolution of the city valley, the coastal zone, and the nearshore seabed. On land, the study area is the lower part of the river valley located between the archaeological site and the foothills of the Agia Triada coastal hill. Data were acquired by geomorphological and geophysical research, drillings (up to 14.5 m depth) stratigraphical and paleontological analysis, and high accuracy topography using GNSS receivers and Unmanned Aerial Vehicles (UAVs). The marine survey extends to the entire Voroskopos (Poliochni) Bay including satellite image analysis, single-beam echo soundings, side-scan sonar seafloor detection and imaging, and visualization of special seabed features.Ancient Poliochni was founded on a coastal terrace shaped by the erosive action of the waves on the hard formations of the Limnos Island geological basement. The seabed morphology and geology of the Poliochni Bay shows that it was part of the coast, during the city habitation, in a progressively flooded by the rising sea level coastal environment.

In this paper, we focus on the southeastern coastal zone of the island of Samos (east-central Aegean Sea), in order to reconstruct the evolution of coastal landscapes and the relative sea-level changes during the late Holocene. We use geomorphological mapping, sedimentological and palaeontological proxies of late Holocene coastal deposits from two lagoon environments. We further compare our results with previously published sea-level data and we show that the southeastern part of Samos was characterized by a subsidence trend at least during the late Holocene, with RSL rise rates of ∼0.8 mm/yr. Our study additionally highlights that local-scale tectonics is responsible for the evolution of the coastal zone of Samos.

A paleoenvironmental reconstruction of the landscape of Nea Raedestos Toumba in the Anthemous River valley in central Macedonia, Greece is undertaken using multidisciplinary geoarchaeological methods. The archaeological site is a settlement mound (tell or toumba) that dates to the Neolithic period and the Bronze Age. The tell’s location on the alluvial plain prompted a multidisciplinary investigation to reconstruct the influence of landscape changes on prehistoric settlements in the valley with an emphasis on alluvial sequences. An electrical resistivity tomography survey and three cores were drilled to study the sedimentary environments in and around the archaeological site. Sedimentologic and palynological analysis combined with accelerator mass spectrometry radiocarbon dating show that the oldest habitation layers at the site, from the Middle and Late Neolithic, were located next to a small, periodically drying water body surrounded by ruderal vegetation. Diatom analysis suggests that this water body was supplied by saline/brackish groundwater. The water body was open until the Early Bronze Age, when it was filled and buried by floodplain sediments. This flooding phase at Nea Raedestos likely occurred at the same time as an increase in fluvial aggradation in the neighboring Thessaloniki Plain, which is dated to the beginning of the third millennium BC.

The integration of lithology determination, micropaleontological and molluscan analyses, scanning electron microscopy, magnetic susceptibility measurement, and radiocarbon dating contributed to the interpretation of a sedimentary succession recovered from a 870-cm long borehole drilled at the Paliouras coastal lagoon in the eastern Thermaikos gulf (Greece). In this way, the reconstruction of the creation and evolution of the lagoon during the last 8000 years was accomplished. Four main evolutionary phases are identified: (1) initially, the pre-Holocene basement of the study area was inundated during the early Holocene marine transgression; (2) since ~ 8000–7900 cal yr BP an inner lagoon had been formed in the Paliouras coastal plain, within a rather restricted environment characterized by a Haynesina germanica, Cerastoderma glaucum and Hydrobia sp. assemblage, relatively high sediment magnetic susceptibility and an intense presence of abnormal foraminiferal tests and lenticular gypsum crystals; (3) during 7600–6900 cal yr BP, the inner lagoon presented a transition to an open system, clearly connected to the sea and characterized by an Ammonia beccarii, Aubignyna perlucida, and miliolids assemblage, more diversified molluscan fauna, minimum sediment magnetic susceptibility and the occurrence of lenticular gypsum aggregates; and finally (4) since ~ 5900 cal yr BP to the present time, the lagoon water body appears isolated from the marine environment, except of occasional seawater intrusions. The proposed evolutionary scenario for the Paliouras coastal lagoon is in accordance with the existing models of the sea level rise in the Aegean coastal areas concerning the time span before 4000 yr BP and the mid-late Holocene climate events.

We present a case study of a long-term integrated monitoring of a flood event which affected part of the Strymonas dammed river basin, a transboundary river with source in Bulgaria, which flows then through Greece to the Aegean Sea. The event, which affected the floodplain downstream the Kerkini dam, started at the beginning of April 2015, due to heavy rain upstream of the monitored area, and lasted for several months, with some water pools still present at the beginning of September, due to the peculiar geomorphological conditions of the watershed. We collected a multi-temporal dataset consisting of a high-resolution, X-band COSMO-SkyMed, and several C-band Sentinel-1 SAR and optical Landsat-8 images of the area. The results allow following the event in time, sketching a multi-temporal map of the post-flood evolution, with relatively high temporal resolution. We then use hydrological modeling to mimic the dynamics of the flooded area against post event weather patterns and thus explain the observed flood extent evolution. We show how integrating remote sensing-derived maps of flooded areas, geomorphological analyses of the landscape and simplified hydrological modeling allows accurate inference about long-term dynamics of flooded areas, very important in the post event in anthropogenic highly modified areas, where recovery time after the flood event is considerable, and long term water persistence may lead to large consequences, carrying economic damages and medical emergencies.

The paleoenvironmental evolution of Lake Ismarida in Thrace (Northern Greece) is revealed by the combined lithological, micropaleontological (benthic foraminifera, pollen and NPPS), molluscan analyses, magnetic susceptibility measurement and radiocarbon dating of a 5.8-m long sediment core. The mid Holocene evolution of the lake area is evidenced by the documentation of four sedimentary Units in the core ISMR-2, corresponding to four distinct evolutionary stages: (1) during ∼5500-3500 cal yr BP the lake area was a shallow marine environment characterized by an Ammonia beccarii, small rotaliids, miliolids, Bittium reticulatum and Veneridae spp. assemblage, marine dinoflagellate cysts, and low magnetic susceptibility values; (2) during ∼3500-3000 cal BP the environment is gradually tending to more isolated conditions forming an open lagoon, characterized by marine and euryhaline fauna and low magnetic susceptibility values; (3) during 3000 cal yr BP, the open lagoon presented a transition to an oligohaline inner lagoon, characterized by an Ammonia tepida, Haynesina germanica, Aubignyna perlucida, Pirenella conica, Cerastoderma glaucum and Abra spp. assemblage, sedges and aquatic vegetation. This restricted, entirely isolated from the sea inner lagoon could be definitely used as the landmark of the Lake Ismaris from Heorodotus, while describing the march of Xerxes through Thrace in 480 B.C.; (4) since ∼2000 cal yr BP to the present, the Lake Ismarida is formed, characterized by fresh-water indicators and aquatic pollen, Pseudoschizaea and high magnetic susceptibility values. Finally, the progradation of the Filiouris River deltaic deposits resulted to a 4 km wide deltaic plain between Lake Ismarida and the nowadays coastline. Pollen assemblages record the dominance of a rather rich deciduous forest in the area with traces of human presence in the lower part of the sequence, whereas the opening of the plant landscape under the increasing human pressure is evidenced after ∼ 3000 cal yr BP. Finally, an open vegetation pattern, contemporaneous with the retreat of forest vegetation, is evidenced in the area already before 2000 cal yr BP.

This paper presents an integrated approach to assess Holocene environmental changes in the Sperchios delta, Sperchios rift, central Greece. A multidisciplinary study was carried out applying established analytical methods as well as exploring new techniques to detect past environmental conditions in a fluvio-deltaic depositional system. A series of six deep boreholes, up to 50 m long, and four shallow cores, up to 6 m long, from across the delta plain, were studied in detail. Sedimentary facies were defined by changes in grain size and macro- and microfaunal composition. Variability in mineral magnetic composition documented by changes in bulk magnetic susceptibility (χ and χ77K/χ293K) and remanence parameters ( S−300 and σARM/σSIRM ratios), as well as down-core elemental variations obtained by scanning micro-x-ray fluorescence (µ-XRF), provide constraints on the depositional changes related to the evolution of the Sperchios delta. Correlations between elemental data derived by µ-XRF analyses and grain size were also analyzed and used to further constrain the facies interpretation. Overall, these Holocene sediments reveal a transgressive–regressive succession overlying pre-transgressive terrestrial deposits of Late Pleistocene–Early Holocene age. Furthermore, 13 new 14C radiocarbon dates constrain the transgression rate to be ~3.5 m/yr for the Early Holocene and the regression rate to be ~1 m/yr for the Late Holocene. The Sperchios delta plain developed when the rate of sea-level rise decreased ~6000 cal. yr BP as it has been proposed for the broader area of Aegean Sea. This study demonstrates that the combination of techniques used here provides a powerful way to map out paleoenvironmental changes and thus the 3D stratigraphic architecture of Holocene sedimentary successions.

The Athenian Basin is a very interesting area from an archaeological point of view, since it is inhabited from Neolithic time. The human impact on the landscape is shown by the ancient constructions such as the Long Walls and the canalization of the rivers in the area of the Athenian Basin and Piraeus. The aim of the study is to detect the paleogeographical evolution of this area. In order to manipulate all the available information obtained from literature review (topographic maps, geological maps, ancient maps and references) and the stratigraphic data from 227 boreholes from the Athenian Basin, a GIS database was established. After the interpretation of the stratigraphy from the boreholes, six lithostratigraphic units were defined. Maps and 3D models were designed to represent the succession of the lithostratigraphy of each period. Paleogeographic maps were created in order to represent the landscape for each lithostratigraphic unit of the Athenian basin, and extract results for the temporal and spatial changes of the paleo-landscape and the involvement of the human impact on the depositional process in the Athenian Basin during Holocene.

Anthemous Valley, located in Northern Greece, has witnessed two different models of habitation during the Neolithic, while the Bronze Age comprises only of tell sites. Until recent no tell settlement model was recorded that could be associated with the Neolithic. Following article discusses the results of geoarchaeological works in Nea Raedestos which revealed the presence of another – third type of Neolithic settlement – a tell type. The ERT, vibracoring and laboratory analyses provided material for archaeological comparisons between the discussed site and other Neolithic record in the Anthemous Valley. In the light of results, the Nea Raedestos Neolithic site differs in terms of spatial organization from the already known extensive settlements in Vassilika-Kyparissi, Thermi and Galatista, and thus constitutes first evidence of Neolithic tell in the Anthemous Valley.

Naxos Island is situated in the Cycladic plateau (middle Aegean Sea) and consists of concaved beach zones separated by small headlands. This study investigates the diachronic palaeo-shoreline shift due to the sea level change and its effect to the palaeo-environmental evolution of the western coastal part of Naxos Island during the Late Holocene. For this purpose, six boreholes were drilled and dated using radiocarbon techniques. The associated geomorphological, sedimentological and paleontological investigation concluded that during Late Holocene, the embayments of Naxos western coastal part were frequently exposed, and their communication with the sea was not perennial. The coastal area was wider with many active lagoons and embayment changing from shallow marine environment to coastal environment frequently alternating to brackish mesohaline one. The former sea-level position in western Naxos island should be between −1.5 m and −2 m during the last 2000 years, which may partly reflect eustatic processes and partly a gradual or coseismic land subsidence.

The Saint Georgios coastal zone, located at the W coast of Naxos, the largest island of the Central Aegean Sea, was investigated in order to determine the palaeo-geography, sea level changes and their effect to the palaeo-environment of western Naxos island and to human activity. Detailed geomorphological mapping, study of micropaleontological and sedimentological characteristics and dating analyses of the Late Holocene of St. Georgios coastal zone were conducted. To obtain information about the Holocene stratigraphy under the recent alluvial cover, three boreholes followed the detailed geomorphological mapping. Microfaunal analysis took place and five samples of plants, shells, peat and charred material were also collected from several layers of the sedimentary sequence and were dated using AMS and conventional radiocarbon techniques providing temporal control of the sediments. The sea-land interactions during Upper Holocene, in relation to the eustatic sea level oscillations, as well as the geomorpholog...

The battle of Thermopylae (Malian Gulf, Central Greece) is one of the most famous ancient battles in European and world history. It took place on a narrow strip of land where it was possible for a few thousand Greeks to fight against the Persian army. The geomorphology of the battle terrain has changed significantly since ancient times due to the Sperchios River delta progradation. In this work an attempt is being made to undertake a palaeogeographical reconstruction of the pass and the battle terrain in Ancient Thermopylae in order to set out new information based on new geoarchaeological data. Geomorphological data in combination with geological, stratigraphical, paleontological data of an extensive drilling project supported by electrical resistivity tomography led to the determination of the palaeoenvironmental changes in the area of the Thermopylae Pass and for the palaeogeographical reconstruction of the battle terrain in ancient Thermopylae. The results of this research showed that in the “middle g...

Holocene palaeoenvironmental changes in the area of the prehistoric settlement of Megali Vrysi close to the village of Agia Paraskevi in Central Greece, 5 km east of Lamia City, were investigated. The area is situated in the low flat alluvial plain on the outskirts of Sperchios Valley that is bordered NNW to ENE by a rocky, hilly ridge of the Othrys Mountain foothills, 5.5 km away from the present coastline. The Megali Vrysi site is considered to be an important Mediterranean prehistoric commercial centre. Reconstruction of the palaeoenvironmental changes of the broader area adds new information concerning the general palaeogeographical setting of the settlement. Multidisciplinary research involved a detailed geomorphological survey combined with stratigraphical, palaeontological, and geophysical studies. The penetrated strata differentiated into 4 units from top to bottom. The first represents the archaeological strata. The second consists of the freshwater marshy sediments, while the third is the transition layer between the second and the deeper fourth group of marine – lagoonal sediments. The Holocene stratigraphy data was combined with the 14 C-AMS dating results and showed a marine palaeoenvironment (∼ 5500 BC) gradually having shifted to a coastal – lagoonal one (∼3500 BC) and finally changed to a freshwater marshy environment (∼2500 BC). The comparison between ages and depths of the relative sea level points allowed the estimation of the sea level rise rate for the Agia Paraskevi area which is considerably lower than the one proposed for the Aegean Sea in the same time period. This considerable offset is attributed to the intensive tectonic uplift of the study area due to the tectonic deformation of the Sperchios Valley and this is probably why the prehistoric coastal settlement remained on the surface and unaffected from the sea transgression for more than 7000 yrs during Holocene.

In tectonically active areas drainage systems are often influenced by the type, geometry, and recent activity of regional and local faults. In the Perachora peninsula, eastern Gulf of Corinth (Greece), most drainage networks are influenced by neotectonic processes and eustasy. Two major east–west trending fluvial systems (Perachora and Pissia) in the southwestern part of the peninsula are affected by faults of similar orientation. Detailed geomorphological mapping was performed focusing on knickpoints, gorges, planation and depositional surfaces, alluvial fans and talus cones. Longitudinal river profiles and hypsometric curves of their basins were constructed utilizing GIS technology. The two drainage systems exhibit opposite network asymmetries. The Pissia network is well developed south of the main channel while the Perachora extends to the north. The analysis of the longitudinal profiles of the main stream channels denotes that they exhibit different evolutionary trends. The Pissia stream has a “transverse” drainage crossing the active Loutraki fault, while the Perachora stream has a “parallel” evolution as it has the same orientation as the Loutraki fault. The drainage system of Pissia is much older than the Perachora as a large part of the latter was underwater in Late Pleistocene times. The combination of eustacy and vertical tectonic movements has led to the development of four marine terraces corresponding to previous high sea-level stands during Oxygen Isotope Stages (OIS) 5e, 7e, 9c and 11c. Following the analysis of the longitudinal profiles and the hypsometric curves two depositional surfaces were verified at Perachora village. The first surface at 280–360 m and the second one between 120 and 160 m are probably related to marine terraces 11c and 7e respectively. The development of the present drainage systems of Perachora and Pissia in the Late Quaternary depends mostly on the fault tectonism of the two main offshore fault systems of Xylokastro and Loutraki resulting in the uplift of marine terraces to heights of more than 300 m, but also due to the inland faults (Pissia and Alepochori) which created depositional surfaces and knickpoints. Sea-level changes have played a secondary role in the development of the drainage systems.

During the Holocene, the western part of the present-day Thessaloniki coastal plain (north-central Greece) was flooded by the rising sea level and formed a bay as a consequence of the last postglacial transgression. The rate of the sealevel rise subsequently decelerated, and this bay began to fill with sediments delivered by the Aliakmon and Axios, as well as by other smaller rivers. The palaeogeographic and palaeoenvironmental reconstruction of the Thessaloniki Plain was the focus of several studies published during the past century. Most of these studies are based on the interpretation of historical sources and support the assumption of a fast filling of the bay between the fifth century BC and the fifth century AD. In this work, we first present the results of the analysis of data collected from six boreholes recently drilled in the western part of the plain, up to the western bank of the Axios River. Our study was mainly based on sedimentological and palaeontological analyses and accelerator ...

The plain of Thessaloniki is an important area from a historical standpoint. Numerous reigns and empires have occupied the area, leaving behind numerous archaeological remains. The literature and historical evidences show that the city of Pella was located near the sea and its harbor was the starting point of various conquests of famous kings such as Philip the 2nd and Alexander the Great. At present, the ancient capital is located 28 km inland the large fertile plain of Thessaloniki. Palaeogeographic and palaeoenvironmental studies encourage the idea of a fast infilling of the plain between the 5th century BC and the 5th century AD. Twentieth century authors attest to this, but there are contradictory scenarios due to varying interpretations of literature sources. This research offers a new perspective and understanding of the evolution of the Thessaloniki plain based on chronostratigraphical evidences. Historical references of Herodotus, Livy, and Strabo were used to establish the relations between human occupation and landscape evolution. Crossing these chronostratigraphical data with archaeological evidences and literary sources, it was possible to reconstruct shoreline displacements and landscape evolution during the last 5 millennia.

The Katarraktes cave system is located in northern Greece and is a complex of a rockshelter and a cave formed on the south river bank of Krousovitis River canyon (Serres, Macedonia region). The archaeological site area is well known as one of the most important archaeological sites in SE Europe since it hosts numerous archaeological findings dating back to the Early Bronze Age. Detailed stratigraphic analysis of three archaeological sections was performed in order to define the depositional conditions of the cave entrance facies sediments. Mineral magnetic properties were performed to enhance the paleoenvironmental interpretations and to detect sediment origins. Magnetic susceptibility (klf) obtained in high and low frequency as well as remanence parameters, such as saturation isothermal remanent magnetization (SIRM) and S-ratio, were measured in samples collected2from the archaeological sections. Results indicate a significant variability in the magnetic signal stored in the sedimentary record of Kataraktes cave system distinguishing between natural and anthropogenic sequences. The combination of the stratigraphic and magnetic results along with the archaeological data reveals that flood events of Krousovitis River and sediment accumulation from slackwater in the rockshelter area occurred around 3000 yr BC and were possibly the key factor for the abandonment of the prehistoric settlement.

On December 17, 2009, a large size rock fall generated at the area of Tempi, Central Greece causing one casualty. In particular, a large block was detached from a high of 70 meters and started to roll downslope and gradually became a rock slide. About 120 tones of rock material moved downward to the road resulting to the close of the national road. Few days after the slope failure, a field survey organized by the Department of Geology, AUTH took place in order to evaluate the rock fall hazard in the area and to define the triggering causal factors. As an outcome, we concluded that the heavily broken rock mass and the heavy rain-falls, of the previous days, contribute significantly to the generation of the slope failure. The rocky slope was limited stable and the high joint water pressure caused the failure of the slope.

Ο ποταμός Κηφισός με τους παραποτάμους του αποτελεί το κύριο ποτάμιο σύστημα αποστράγγισης της υδρολογικής λεκάνης των Αθηνών. Αποστραγγίζει το κεντρικό κομμάτι της Αττικής και ένα πολύ μεγάλο μέρος του πολεοδομικού συγκροτήματος της Αθήνας. Στην εργασία αυτή παρουσιάζονται τα ποιοτικά και ποσοτικά αποτελέσματα της ανάλυσης του αρχικού υδρογραφικού δικτύου του Κηφισού ποταμού πριν από την αστικοποίηση της υδρολογικής του L·κάvης. Η μελέτη αυτού του φυσικά αναπτυσσόμενου υδρογραφικού δικτύου, έγινε με την χρήση ψηφιακών δεδομένων τα οποία αναλύθηκαν σε λογισμικό Γεωγραφικών Συστημάτων Πληροφοριών. Η αποτύπωση του αρχικού υδρογραφικού δικτύου της λεκανοπεδίου των Αθηνών έγινε με τη χρήση και την ψηφιακή επεξεργασία εξαιρετικά L·πτoμεpώv ιστορικών χαρτών που κατασκευάστηκαν από τους γερμανούς χαρτογράφους Curtius Ε. και Kaupert J. στα τέλη του 19ου αιώνα. Για την ανάλυση του υδρογραφικού δικτύου εφαρμόστηκαν οι νόμοι της υδρογραφικής σύνθεσης και προσδιορίστηκαν οι τιμές της υδρογραφικής πυκνότητας και συχνότητας. Ένας από τους βασικούς στόχους της εργασίας αυτής είναι ανάδειξη των φυσικών και περιβαλλοντικών συνθηκών του πεδίου των Αθηνών πριν από την αστικοποίηση της περιοχής. Μια τέτοια πληροφορία είναι εξαιρετικά χρήσιμη και αποτελεί σημαντικό γεωμορφολογικό - περιβαλλοντικό εργαλχίο προσδιορίζοντας και παράλληλα διαχωρίζοντας τις φυσικές διεργασίες εξέλιξης του ποτάμιου συστήματος από τις ανθρωπογενείς επεμβάσεις, Kephissos River is the main fluvial system of the hydrological basin of Athens. It drains the central part of Attica and almost the entire urban area of the city of Athens. In this paper, we present the results of both the qualitative and quantitative analysis of the initial drainage network of the plain before the urbanization through the processing of digitised data with GIS software. The initial drainage network of the. basin, plotted with the use of a very detailed mosaic of maps, was constructed by German cartographers (Curtius E. and Kaupert J.) at the end of the 19' century. For the analysis of the drainage network the Laws of drainage composition were used and values for the D and F indices were calculated. One of the major aspects of this article is \o reveal information about the fluvial and environmental conditions in the plain of Athens before the urbanization of the area. This kind of information is very critical because until that time (end of the 19th century) the fluvial system of Kephissos\ was natural, without any human intervention.