Eleni Koutsopoulou | University of Patras (original) (raw)

Papers by Eleni Koutsopoulou

American Mineralogist, 2017

Clay Minerals, 2016

Greece is a major bentonite producer, with Milos Island being one of the largest bentonite mining... more Greece is a major bentonite producer, with Milos Island being one of the largest bentonite mining centres in the world. In addition to the bentonite deposits which are well known, various other occurrences exist in the islands of Chios and Samos, Eastern Aegean and in some areas of Thrace, in NE Greece. These bentonites are associated with volcanic activity and their age ranges from Lower Oligocene in Thrace, to Lower–Middle Miocene in Chios and to Upper Miocene in Samos. Although some of these materials have been utilized since ancient times (e.g.the Samian Earth), these bentonites have been mined only at a local scale. In this study the first data on the mineralogical and geochemical characteristics of these bentonites are presented.The Samos bentonites of UpperMiocene age are medium–lowgrade (40–70% smectite) and crop out in the SE margin of the Karlovasi Basin formed at the expense of acidic pyroclastic flows mainly in a subaeriallacustrine environment. They consist mainly of Ca...

Goldschmidt2021 abstracts

International Conference on Raw Materials and Circular Economy

Journal of Marine Science and Engineering

Zeitschrift für Geomorphologie

Beachrocks are coastal sedimentary formations, which are relatively quickly cemented through the ... more Beachrocks are coastal sedimentary formations, which are relatively quickly cemented through the precipitation of CaCO 3. Beachrock formation is widespread in low latitudes (i.e. the Mediterranean coastlines) and the cementation process near the sea level can be a potentially fast procedure; therefore, beachrocks can be used as sea level indicators. However, in many studies, debate still exists regarding their depositional environment and their use as indicators for sea-level changes. This study focuses on the beachrocks of Naxos and Paros Islands, in central Cyclades, Aegean Sea (Greece), aiming to contribute to the further understanding of their formation mechanism and palaeoenvironmental significance. For this purpose, a multi-analytical approach was accomplished, with the use of microscopic investigation, scanning electron microscope, energy-dispersive x-ray spectroscopy, x-ray diffraction and x-ray fluorescence. Our analysis revealed that the beachrocks of Naxos and Paros Islands were primarily formed in an environment equally saturated by sea and fresh water, at the middle intertidal zone. Calcite supersaturation in the water along with the de-gas of pore CO 2 and the microbial activity, which resulted to physicochemical precipitation of High Magnesium Calcite (HMC), were the main mechanisms contributing to their formation. Our study highlights how multi-analytical methods may be used for more precise sea level reconstructions using beachrocks.

Nature Communications, 2015

Geo-Marine Letters, 2013

ABSTRACT The Pagassitikos Gulf in Greece is a semi-enclosed bay with a maximum depth of 102 m. Ac... more ABSTRACT The Pagassitikos Gulf in Greece is a semi-enclosed bay with a maximum depth of 102 m. According to the present-day bathymetric configuration and the sea level dur-ing the latest Pleistocene, the gulf would have been isolated from the open sea, forming a palaeolake since ~32 cal. ka B.P. Sediment core B-4 was recovered from the deepest sector of the gulf and revealed evidence of a totally different deposi-tional environment in the lowest part of the core: this contained light grey-coloured sediments, contrasting strongly with overlying olive grey muds. Multi-proxy analyses showed the predominance of carbonate minerals (aragonite, dolomite and calcite) and gypsum in the lowest part of the core. Car-bonate mineral deposition can be attributed to autochthonous precipitation that took place in a saline palaeolake with high evaporation rates during the last glacial–early deglacial peri-od; the lowest core sample to be AMS 14 C dated provided an age of 19.53 cal. ka B.P. The palaeolake was presumably reconnected to the open sea at ~13.2 cal. ka B.P. during the last sea-level rise, marking the commencement of marine sedimentation characterised by the predominance of terrige-nous aluminosilicates and fairly constant depositional condi-tions lasting up to the present day.

Materials Proceedings, 2022

Samples were collected from the argillic alteration zones in Sappes area, Thrace, Northern Greece... more Samples were collected from the argillic alteration zones in Sappes area, Thrace, Northern Greece and were examined for their mineralogical composition. Results showed that the sericite zone is the most widespread type of alteration in the studied area, followed by the transitional sericite–kaolinite zone and finally the pyrophyllite-rich zone. After determination of the spatial distribution of the different argillic alteration zones, selected samples were examined for their technological ceramic properties in order to evaluate their use in ceramic production. Preliminary results showed that after beneficiation processes, the clayey raw material from the alteration zones could be used in the ceramic industry

Journal of Marine Science and Engineering, 2022

Beachrocks are a window to the past environmental, geological, sedimentological and morphological... more Beachrocks are a window to the past environmental, geological, sedimentological and morphological conditions that were dominant in the coastal zone during their formation. Furthermore, beachrocks have the ability to reduce coastal erosion impact on sandy beaches. This study focuses on the beachrock formation mechanism through the comparison of cement characteristics, mineral chemistry and sedimentology of beachrock occurrences from two different geological and geographical localities: Diolkos, Corinth, Greece and Sumuide, Okinawa, Japan. In addition, in order to investigate a potential soft engineering method to protect coasts from erosion, artificial beachrock samples were created in vitro using sand samples and ureolytic bacteria from both areas under accelerating conditions. For Okinawa artificial beachrock experiments, the bacteria Pararhodobacter sp. was used, and for Diolkos, it was the bacteria Micrococcus yunnainensis sp. For the natural beachrocks, a multi-analytical approach was accomplished with the use of microscopic investigation, a scanning electron microscope, energy-dispersive X-ray spectroscopy, X-ray diffraction and X-ray fluorescence. Correlations were made between natural and artificial beachrocks. Results have shown that Diolkos beachrock was formed in the upper part of the intertidal zone, consisting of detrital material originating from the local bedrock, while Sumuide beachrock formed in the low intertidal–upper subtidal zone, consisting of coral sand and foraminifera fragments. For the artificial beachrocks, three samples were created using the microbial-induced carbonate precipitation (MICP) method, one from Diolkos (Corinth, Greece) and two from Sumuide (Okinawa, Japan). Diolkos artificial beachrock was better consolidated in comparison to Sumuide. Our investigation has shown that bacterial density was the key factor for the creation of the artificial beachrocks, while the samples’ granulometry played a secondary role in the process. The laboratory artificial beachrocks show encouraging results for a new soft engineering method to encounter beach erosion while keeping an ecofriendly character by saving energy, material resources and gas emissions. Artificial beachrocks can share the same properties of a natural beachrock and can contribute positively to marine biodiversity as a natural rocky habitat.

The ROBOMINERS (Resilient Bio-inspired Modular Robotic Miner) project aims at de... more The ROBOMINERS (Resilient Bio-inspired Modular Robotic Miner) project aims at developing new methods and technologies (prototype automation and robotics technology) to locate and exploit underground mineral deposits and is funded under the European Union&#8217;s Research and Innovation programme Horizon 2020. The project targets mineral deposits that are generally considered &#8220;non-economical&#8221; either because they are not accessible anymore for conventional mining techniques, or they have been previously explored but exploitation was considered uneconomic due to the small size of the deposits or the difficulty to access them (abandoned, small, ultra-depth deposits).&#160;The European Federation of Geologists (EFG) is part of the Robominers consortium and its role includes the collection of publicly available data at a national level on mineral deposits which are potential targets on the developed mining technology. The Association of Greek Geologists (AGG) is participating as an EFG Linked Third Party in the project aiming, among others, at the creation of a European database of potentially suitable ore deposits for the utilization of the Robominers technology.&#160;The creation of an ore deposits&#8217; European database is a crucial procedure for the best possible design of exploration and exploitation applying the Robominers innovative approach. The AGG has contributed in the building of a database at a national level (for Greece), of the major and most important mineral deposits, according to the project requirements. A number of ore deposits in which Robominers advanced technology may provide a unique solution to mineral extraction, include porphyry and epithermal deposits and especially vein-like types, but volcanogenic massive sulphide (VMS-type) and lense-like or layered orthomagmatic deposits can also be of high importance. From the above mentioned ore deposits the most abundant in Greece are epithermal deposits, deposits in hydrothermal veins, porphyry copper, as well as chromites in ophiolite complexes. Regarding the spatial distribution vein-type or metasomatic deposits are located mostly in Northern Greece (Western Macedonia and Thrace regions) while significant variable-mineralization deposits are related with the Attico-Cycladic belt volcanism (mainly Lavrion, Evia, and islands in the Aegean Sea). Finally, PGE bearing chromite deposits and bauxite deposits, located mainly in Central Greece, may also be significant for the project.&#160;The establishment of a joined European Robominers database is of great significance for the progress of the project since it will provide essential information on key outputs such as the deposit type and commodities, the host rock, and the spatial distribution of the project&#8217;s targeted ore deposits and will provide valuable knowledge regarding the future planning of the exploration and exploitation from the developed Robominers innovative technology approach.Dr Eleni KoutsopoulouCoordinator of the projectOn Behalf of the:Association of Greek GeologistsDidotou 26,10680, Athens, GreeceVAT ID: EL-999600130&#160;&#160;

1 1 Hellenic Centre for Marine Research ( CMR), , Greece. E-mail: ak@ cmr.gr H 46.7 km Athens-Sou... more 1 1 Hellenic Centre for Marine Research ( CMR), , Greece. E-mail: ak@ cmr.gr H 46.7 km Athens-Sounio Avenue, 19013, Anavyssos h Leibniz-Institute for Marine Sciences, IFM-Geomar, 24148 Kiel, Germany Department of Geology, Section of Earth Materials, University of Patras, GR-26500, Greece Harokopio University, Faculty of Geography, 70 El. Venizelou Str., 17671 Athens, Greece Department of Geology and Geochemistry, Stockholm University, 10691 Stockholm, Sweden 2

Bulletin of the Geological Society of Greece

Stevensite is a Mg-trioctahedral smectite with layer charge stemming from vacancies in the octahe... more Stevensite is a Mg-trioctahedral smectite with layer charge stemming from vacancies in the octahedral sheet. In the present work we studied the thermal behavior of Jbel Ghassoul stevensite from Morocco, known as Ghassoulite or Rhassoulite, free of talc layers. The clay fraction of the material was separated by sedimentation, it was subsequently heated from 250° to 800° C and the end products were examined with X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy. The influence of heating on the stevensite structure begins at 400°C and is completed at 500°C. It involves irreversible collapse of the layers at ~10Å, which do not re-expand in ethylene glycol (EG) vapors. In contrast, heating at lower temperatures does not affect the stevensite layers, which expand completely in EG. The FTIR spectra indicate the formation of talc-like (kerolite) layers after heating at temperatures exceeding 400°C. Within the current experimental setup, the transition to kerolite la...

Bulletin of the Geological Society of Greece

Therefore, the evaluation of environmental risks associated with a landfill and the effect of lan... more Therefore, the evaluation of environmental risks associated with a landfill and the effect of landfill surface runoff was investigated. Soil samples were collected in the downstream area of the waste disposal site and their mineralogy was studied. An appraisal of the heavy metal contamination in the area was attempted. Top layers of sediments seem to interact with chemically modified surface runoff waters from the landfill. Heavy metals such as As and Pb were in significant concentrations in the sediments within a distance of 200 m from the site. Anions such as chloride, sulphate and phosphate adsorbed on clay minerals suggest the interaction of sediments with surface runoff from the waste disposal site. Inorganic parameters NH4 + and NO2 - in surface water samples are above or slightly below the guidelines recommended by EE and WHO. The results indicated that environmental monitoring of the landfill is considered essential.

Bulletin of the Geological Society of Greece

Research on carbonate rocks has been increasingly important during the last few decades, due to t... more Research on carbonate rocks has been increasingly important during the last few decades, due to their numerous applications. In this paper, we examined the properties of Cretaceous carbonate rocks from the Olonos-Pindos Zone from Ileia Prefecture. The relationships between various physical properties and between petrographic features and physical properties were defined. This may lead to preliminary evaluation of carbonate rocks using microscopic investigation, which unlike the elaboration of a series of physical and mechanical properties, is a fast and inexpensive method. In addition, these properties, along with their geochemical characteristics, were used to assess the suitability of these carbonate rocks as fillers in various applications. Detailed petrographic study of the collected samples revealed the occurrence of biomicrite, intramicrite (mudstone και wackestone), biosparite (packstones and grainstones), intrasparite and rudstone. From the lower to the upper members, a decr...

Bulletin of the Geological Society of Greece

Sanitary landfill facilities are essential to modern societies as repositories for municipal soli... more Sanitary landfill facilities are essential to modern societies as repositories for municipal solid wastes. However, they always entrain a certain risk of environmental impact. For this reason monitoring is essential to their operation. In the present work, the environmental impact of such a landfill is studied. Soil samples were collected in and around the landfill and their mineralogy was studied. Top layers of stream sediments were collected to examine possible dispersion of pollutants in the environment. Chemical analyses showed enrichment in As, Cu, Zn, and Pb in the stream sediments compared to uncontaminated samples. The presence of anions such as chloride, sulphate and phosphate adsorbed on clay minerals suggest the interaction of stream sediments with run-off water from the landfill. The groundwater near the landfill site was characterised as not potable and not suitable for irrigation purposes, because some parameters such as NO3 - and Cl- were close or exceeded the permiss...

Bulletin of the Geological Society of Greece

An extensive oceanographic survey was conducted in the marine area between Kimolos and Sifnos Isl... more An extensive oceanographic survey was conducted in the marine area between Kimolos and Sifnos Islands, a rather poorly-studied sector of the Aegean Sea, in order to gain better understanding of submarine geomorphological features and associated sediment provenance. Multi-beam bathymetry and surface sediment sampling with a box corer were carried out on board R/V Aegaeo, followed by grain-size analysis, XRD and XRF measurements. A large circular depression was identified north of Kimolos reaching a water depth of 743 m, filled with fine grained sediments. Surface sediment distribution is characterized by gradual decrease in grain-size from silty sand to silt in a S-N direction. The mineralogical composition comprises calcite, Mgcalcite, aragonite, dolomite, quartz, K feldspars, plagioclase, amphiboles and clay minerals. Major sediment provinces identified were: (i) the shallow sector proximal to Kimolos, characterized by higher contents in Si, Al, K, Rb and Ba; (ii) the deep area wes...

Materials Proceedings

ROBOMINERS is a new project funded under the European Union’s Research and Innovation Programme H... more ROBOMINERS is a new project funded under the European Union’s Research and Innovation Programme Horizon 2020, which aims at employing a bio-inspired robot, focused on the prospect of mineral exploration and extraction within Europe. ROBOMINERS’ innovative approach combines the creation of a new mining ecosystem through the development of a bioinspired robotic miner prototype, able to explore and mine mineral deposits which are currently considered uneconomic due to their small size and difficulty of access. The main objectives of the project include the creation of a European database of potentially suitable locations for the deployment of this novel technology. The building of the pan-EU mineral deposits database is considered vital for the development of the project as it will provide essential information related to deposit type and commodities, spatial and temporal distribution, and location of exploration targets. Several deposits have been reviewed and examined in Greece as po...

Materials Proceedings

Goldschmidt2021 abstracts

American Mineralogist, 2017

Clay Minerals, 2016

Goldschmidt2021 abstracts

International Conference on Raw Materials and Circular Economy

Journal of Marine Science and Engineering

Zeitschrift für Geomorphologie

Nature Communications, 2015

Geo-Marine Letters, 2013

Materials Proceedings, 2022

Journal of Marine Science and Engineering, 2022

Bulletin of the Geological Society of Greece

Materials Proceedings

Goldschmidt2021 abstracts

XIX INQUA Congress, 2015

In the scope of the France-Greek program PLATON n° 30409XH “EMerChanCy”, this work focuses on the... more In the scope of the France-Greek program PLATON n° 30409XH “EMerChanCy”, this work focuses on the beachrocks of Paros and Naxos Islands, in central Cyclades, Aegean Sea, Greece, in an attempt to study their geochemistry and interpret their palaeoenvironmental significance.
Beachrocks are coastal sedimentary formations, consisting of beach sediments that are relatively quickly cemented through the precipitation of CaCO3. However, debate still exists concerning their depositional environment, and therefore, their use as indicators for sea-level changes.
For the aim of the present study, representative bulk samples from both islands were analyzed for their mineralogical (XRD) and chemical compositition (SEM). Chemical analyses were performed by XRF . The cement agent and the fine sand/clay fraction of the samples mainly consist of authigenic magnesian calcite, which commonly precipitates in shallow marine environments, especially in high concentration of Ca2+(>4 mol% CaCO3 or 1.2 wt.%). Furthermore, a series of clastic silicate and alumino-silicate minerals are detected. The predominant coarse fragments hosted within cement material are quartz, albite and K-feldspar.
The texture of the beachrock samples varies from almost homogeneous sandstone to a mixture of lithologies, such as massive gravel, sandstone and claystone. Most of the grains are flattened and only rarely angular pieces of siliceous rocks occur, hosted in the fine-grained Mg-calcite cement. This grain size and shape is indicative of the genetic environment of beachrocks, implying the maturity level of cementation from early stage to modern situation.
The beachrock samples derived from various depositional periods and depths, from the front and end slabs. The beachrocks were also correlated with stratigraphical material from boreholes and archaeological remains from the study area in an attempt to understand the coastal changes during the late Holocene in Central Cyclades.