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Massimo Delfino - One of the best experts on this subject based on the ideXlab platform.
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food for thought sub fossil and fossil chelonian remains from franchthi cave and Megalopolis confirm a glacial refuge for emys orbicularis in peloponnesus s greece
Quaternary Science Reviews, 2016Co-Authors: Evangelos Vlachos, Massimo DelfinoAbstract:Abstract Peloponnesus peninsula (S. Greece) shows a remarkable extant chelonian fauna that has received considerable attention from a molecular and morphological point of view. Here we present new evidence from the fossil and sub-fossil record of two important sites in the area, Franchthi Cave and Megalopolis. The archaeological material from Franchthi Cave (Upper Paleolithic – Neolithic/latest Pleistocene – early Holocene) represents food remains from small game prey of the humans that inhabited the cave. The palaeontological material from Megalopolis (Late Pleistocene) comes from old and new excavations. The studied specimens, combined with information from molecular, climatic and zoological works, provide for the first time direct evidence for the presence of the European pond turtle, Emys orbicularis, in the glacial refuge of South Greece that was hypothesized on the basis of the results of molecular investigations. We also describe other chelonian taxa present in the localities, the Hermann's tortoise Testudo hermanni and the Balkan stripe-necked terrapin Mauremys rivulata, and review previously published chelonian material from Peloponnesus.
Evangelos Vlachos - One of the best experts on this subject based on the ideXlab platform.
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food for thought sub fossil and fossil chelonian remains from franchthi cave and Megalopolis confirm a glacial refuge for emys orbicularis in peloponnesus s greece
Quaternary Science Reviews, 2016Co-Authors: Evangelos Vlachos, Massimo DelfinoAbstract:Abstract Peloponnesus peninsula (S. Greece) shows a remarkable extant chelonian fauna that has received considerable attention from a molecular and morphological point of view. Here we present new evidence from the fossil and sub-fossil record of two important sites in the area, Franchthi Cave and Megalopolis. The archaeological material from Franchthi Cave (Upper Paleolithic – Neolithic/latest Pleistocene – early Holocene) represents food remains from small game prey of the humans that inhabited the cave. The palaeontological material from Megalopolis (Late Pleistocene) comes from old and new excavations. The studied specimens, combined with information from molecular, climatic and zoological works, provide for the first time direct evidence for the presence of the European pond turtle, Emys orbicularis, in the glacial refuge of South Greece that was hypothesized on the basis of the results of molecular investigations. We also describe other chelonian taxa present in the localities, the Hermann's tortoise Testudo hermanni and the Balkan stripe-necked terrapin Mauremys rivulata, and review previously published chelonian material from Peloponnesus.
S.e. Simopoulos - One of the best experts on this subject based on the ideXlab platform.
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radioenvironmental survey of the Megalopolis power plants fly ash deposits
Radioactivity in the Environment, 2005Co-Authors: D.j. Karangelos, P K Rouni, E P Hinis, N P Petropoulos, M.j. Anagnostakis, S.e. SimopoulosAbstract:Publisher Summary The Megalopolis lignite field basin is located in the centre of the Peloponnesus peninsula in southern Greece. The lignite fired power plants in operation in this region have a total capacity of 850 MW and produce over 2 million metric tons of fly ash annually; this is primarily disposed of in deposits located mainly at exhausted lignite mines. The disposed fly ash has a 226Ra content of about 1000 Bq kg −1 . It is concluded that, from the natural radioactivity point of view, the exhausted lignite mines at Megalopolis, in the way that they are restored by fly ash deposition, do not significantly differ from the rest of the Megalopolis lignite field basin, despite the fact that most of the underground soil layers consist of fly ash with high 226 Ra content. A possible explanation for this might be that the radon emanation power from the fly ash layer is as low as the radon emanation power from natural soil due to a fly ash crystallization process in the power plant furnace.
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radioenvironmental survey of the Megalopolis lignite field basin
Science of The Total Environment, 2001Co-Authors: P K Rouni, E P Hinis, N P Petropoulos, M.j. Anagnostakis, S.e. SimopoulosAbstract:Abstract The Megalopolis lignite field basin in southern Greece, with Megalopolis-A and B lignite-fired power plants in operation (total 900 MW), has been repeatedly investigated during the past 25 years by the Nuclear Engineering Section of the National Technical University of Athens (NES-NTUA). The present work aims at an integrated radioenvironmental approach leading to the dose assessment to the public and to the plants staff. This approach includes systematic sampling of lignite and barren at the local lignite mines feeding the power plants and sampling of lignite, fly-ash and bottom ash at the power plants for the determination of the activity of the natural radionuclides 226 Ra, 232 Th, 40 K, 234 Th and 210 Pb. Furthermore, the following measurements and samplings were conducted in 25 selected sites within 10 km around the power plants: soil sampling for the determination of the above radionuclides, radon concentration and exhalation rate measurements, soil gas radon concentration measurements, dose measurements and calculations, determination of air-particulate matter concentration, etc. The results obtained allowed for the mapping of the parameters studied which lead to useful conclusions. Dosimetric calculations for the population living around the power plants and the plants staff were also performed based on the guidance of UNSCEAR (1982 report).
Katerina Harvati - One of the best experts on this subject based on the ideXlab platform.
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in search of pleistocene remains at the gates of europe directed surface survey of the Megalopolis basin greece
Quaternary International, 2018Co-Authors: Nicholas Thompson, Vangelis Tourloukis, Eleni Panagopoulou, Katerina HarvatiAbstract:Abstract The PaGE Project survey of the Megalopolis Basin (Arcadia, Greece), conducted in 2012–2013 over a period of two field seasons, was an intensive, target-oriented surface survey of Pleistocene sediments. Implementing a modified version of field methods applied in our survey of cave systems and Pleistocene cave sediments, the main goal of this systematic research focused on the identification of intact stratified remains from either stratigraphic sections or on remnants of exposed ancient surfaces. The project area consisted of the active open-cast lignite mine of Megalopolis, where access to recently exposed sections were abundant, and of the alluvial fans in the surrounding uplands, where hominins exploited the commanding views of the ancient lake. This paper presents the survey results and applied field methods for conducting archaeological research within the remnants of an Early to Middle Pleistocene ancient lake system. The project succeeded in identifying at least five surface and stratified sites, the latter including the Lower Paleolithic remains of Marathousa-1. This site is currently under investigation, but has already yielded the oldest chronometrically dated archaeological remains in Greece. Therefore, PaGE has not only managed to place mainland Greece on the Lower Paleolithic map of Europe, but has also successfully tested a methodological corpus for survey research targeting the earliest phases of the Paleolithic period in a Mediterranean landscape.
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magnetostratigraphic and chronostratigraphic constraints on the marathousa 1 lower palaeolithic site and the middle pleistocene deposits of the Megalopolis basin greece
Quaternary International, 2018Co-Authors: Vangelis Tourloukis, Eleni Panagopoulou, Giovanni Muttoni, Panagiotis Karkanas, Edoardo Monesi, Giancarlo Scardia, Katerina HarvatiAbstract:Abstract We investigated the magnetostratigraphy of the Megalopolis basin in central Peloponnese, Greece, which encompasses a record of Pleistocene lacustrine and lignite-bearing sedimentation, where lithic tools stratigraphically associated with remnants of an almost complete skeleton of Palaeoloxodon antiquus were recently found at the Marathousa 1 site. A magnetic polarity reversal was observed within a ∼10 m-thick lignite seam at the base of the (exposed) stratigraphic sequence, and it was interpreted as a record of the Brunhes/Matuyama boundary (0.78 Ma). Assuming that lignite seams were deposited generally under warm and humid climate conditions, this finding is in agreement with data from the literature indicating that the Brunhes/Matuyama boundary occurs within warm Marine Isotope Stage (MIS) 19. We then attempted to correlate the remainder of the lacustrine and lignite-bearing intervals above the Brunhes/Matuyama boundary to a standard oxygen isotope record of Pleistocene climate variability. Two age models of sedimentation were generated: according to preferred option #1, the artifact-bearing stratigraphic units of the Marathousa 1 site should have an age between ∼0.48 Ma and ∼0.42 Ma, while according to alternative option #2, the archaeological layers would have an age between ∼0.56 Ma and ∼0.54 Ma. Option #1 is at present considered the preferred option as it is in closer agreement with preliminary post-IR IRSL and ESR dates from the Marathousa 1 site. This age model has been exported to other areas of the Megalopolis basin, where additional archaeological and/or palaeontological sites could be present, by means of correlations to lithostratigraphic logs derived from commercial drill cores taken in the 1960s and 1970s for lignite exploitation.
H. Papaefthymiou - One of the best experts on this subject based on the ideXlab platform.
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source apportionment by pmf on elemental concentrations obtained by pixe analysis of pm10 samples collected at the vicinity of lignite power plants and mines in Megalopolis greece
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2015Co-Authors: M Manousakas, H. Papaefthymiou, R Padillaalvarez, M. Bogovac, Alessandro Migliori, E Diapouli, R. Kaiser, Andreas-Germanos Karydas, Milko Jaksic, I BogdanovicradovicAbstract:Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009–11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11–33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.
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source apportionment by pmf on elemental concentrations obtained by pixe analysis of pm10 samples collected at the vicinity of lignite power plants and mines in Megalopolis greece
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2015Co-Authors: M Manousakas, H. Papaefthymiou, R Padillaalvarez, M. Bogovac, Alessandro Migliori, E Diapouli, R. Kaiser, Andreas-Germanos Karydas, Milko Jakšić, I BogdanovicradovicAbstract:Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009–11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11–33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.
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characterization of pm10 sources and ambient air concentration levels at Megalopolis city southern greece located in the vicinity of lignite fired plants
Aerosol and Air Quality Research, 2013Co-Authors: M Manousakas, Konstantinos Eleftheriadis, H. PapaefthymiouAbstract:PM10 samples were collected in the area of Megalopolis City (Southern Greece) located in the vicinity of two lignitefired power plants during an one-year long period (April 2009–March 2010). The samples were analysed for their BC and elemental concentrations (Ca, Fe, Ti, Mn, Cu, Zn, As, K, Cr, Ni) using a smoke reflectrometer and ED-XRF, respectively. The average PM10 concentration was 21.6 ± 10 μg/m 3 , while that of BC was 1.05 ± 0.55 μg/m 3 . The concentrations of all the elements, except that of K, were significantly higher in the warm period compared to the cold period of the year, whereas the BC results presented the opposite trend. No statistically significant differences were found between mean PM10 mass concentrations during the warm and cold periods. Source identification was attempted by EF calculations and by Condition Probability Function analysis relating the elemental concentrations to wind directions. The results show that soil/road dust re-suspension from opencast mines and unpaved roads, emissions from vehicle exhausts and mining activities, lignite combustion in the lignite-fired power plants and biomass burning, are the main sources of PM10 in the air over Megalopolis City.