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Within the project “Hydrological Monitoring of Wetland Areas Using SAR Techniques (Hydro-SAR)”, concluded by the TERRASIGNA (Romania) with the European Space Agency (ESA), the task of GeoEcoMar was to track and check the correlation of data provided by InSAR techniques with ground observations and measurements in the Danube Delta. Activities in the field and laboratory enabled elaboration of maps of vector fields for the water flow directions on the Danube Delta territory, based on the relief of the water surface levels at 450, 400, 350, 300, 250, 200, 150, 100, 50 and 0 cm, measured at Tulcea hydrologic station. In order to elaborate the maps of water surface levels, the altimetric stability of hydrometric gauges from the Danube Delta territorry was checked by establishing the Earth crust subsidence in each gauge location. Interpretation of recorded data shows a relative low subsidence rate for the location of the hydrometric gauge in Tulcea (observations recorded for the period 1858-2013) selected as hydrometric reference point, with the origin of the zero of the gauge situated at 0.57 m altitude relative to the Black Sea – Sulina reference system. The paper presents isoline maps of the water surface levels on the surface of the Danube Delta between the main distributaries (Chilia – Sulina – Sf. Gheorghe), for the above mentioned water surface levels.

Education was an objective of NRDI GeoEcoMar since its foundation, in order to attract young students to research through organizing various scientific meetings, summer schools, coordinating Master and PhD theses, etc. As European Centre of Excellence for Environmental and Geoecological Studies on River - Delta - Sea Systems in Europe - EuroGeoEcoCentre, during 2003-2006 the institute organized summer schools in the Danube Delta in order to train students from Romania and European countries in the sedimentology of terrestrial and marine systems. Since 2013, annual programs of education and internship for undergraduate students are run by the National Center for Monitoring and Warning on Marine Natural Hazards - Black Sea Security System - in Constanţa. Activities for schools and the general public started in 2010, with public conferences, temporary and travelling exhibitions, as well as various events. Such activities increased between 2016-2017, when a project dedicated to education and promotion of earth sciences was run by the institute. The educational program included educational activities for various types of target audience, activities of popularization and promotion of geological and paleontological sites in two Romanian geoparks, promotion of results accomplished by GeoEcoMar in earth sciences, ecology, marine biology, etc. The educational program developed was structured as education in schools, internship for students and geological literacy of the general public. For education in primary and secondary schools, ten lesson plans on earth sciences were elaborated, with associated hands-on activities. A 5 days field trip in Dobrogea was organized for undergraduate students, while various activities and events were proposed for the general public: public conferences, geological field trips, the Day of Open Doors at GeoEcoMar, Earth Science Week, the School Differently and workshops for children. Geological education is a necessity in Romania, especially as earth sciences do not have an adequate public presence and geological literacy of people is rather low. As geology is no longer part of the school curricula for almost 20 years, except some basic concepts included in the geography programs, education and promotion of earth sciences has to continue, which implies the existence of adequate financial and human resources. [ABSTRACT FROM AUTHOR]

In this paper we are presented the first early-warning system from the Black Sea-EUXINUS network. This represents a complex automatic marine measurement system, Consisting of measuring instruments installed in key points of the western Black Sea, to monitoring coastal wave along Romanian-Bulgarian border. [ABSTRACT FROM AUTHOR]

This paper presents results obtained in two projects of GeoEcoMar, which led from the study of extreme marine events and the inventory of marine geohazards to the creation of a real-time warning system for marine hazards in the Black Sea. Project Profet resulted in establishment of the main marine hazards that could trigger a tsunami-type event in the Black Sea, like earthquakes, active faults, landslides, gas hydrates, gas seeps and mud-volcanoes. Also, major tsunami-type events in the Black Sea were listed and described from various sources. Through project MARINEGEOHAZARD, the EUXINUS and GeoPontica networks have been established, which produce data for the National Data Centres in Constanța and Varna. The EUXINUS network is a complex automatic marine measurement system, consisting of 5 measuring instruments installed in key points of the Western Black Sea shelf. The main task of one of its main components, the Black Sea Security System, is to elaborate risk assessments and to send early-warning notifcations to authorities. [ABSTRACT FROM AUTHOR]

Sediment-associated pollutants are transported by rivers as suspended load and bed load under specific flow conditions. In particular conditions part of pollutants (e.g. metals) could be incorporated into the alluvial deposits, and over time, became a major source of the river contamination. The hydrology, the riverbed morphology and the characteristics and quality of river sediments of the Lower Danube have been studied yearly in the 2009 - 2013 period using different methodologies (single and multi-beam bathymetry, ADCP measurements of current velocity and suspended load, sediment sampling using grabs and corers, laboratory analyses). Yearly measurements and sampling have been carried out on more than 70 cross-sections on the Lower Danube course, between km 1072, where the river enters the Romanian territory, and the Black Sea. From each cross-section, one to three sediments samples were analysed for determining the sediment grain size, mineralogy and chemical composition using different laboratory methodologies, as X-ray fluorescence and AAS techniques for Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V and Zn. The obtained multiannual data allowed identifying the main anthropogenic pollution by heavy metals zones along the river. The Romanian tributaries of the Danube have been sampled and analysed separately for evaluating their role in the general environmental state of the region. The influence of the Danube River water, sediment and pollutants supply to the NW Black Sea has been also studied. [ABSTRACT FROM AUTHOR]

This study describes the fluctuation pattern in Late Holocene microfaunal (i.e. foraminifera and ostracods) and nannofloral assemblages of two cores collected from the Romanian Black Sea shelf, at a water depth of 28 and 66 m, respectively. The lithology of the cores is mainly characterised by blackish muds, alternating with thin, centimetres-thick sand and coquina layers. The microfaunas are dominated by brackish foraminiferal and ostracod assemblages that are still common in the actual Black Sea communities, living nowadays at water salinity lower than 18 ‰. In the shallower water Site EF 08-01, the abundance ratio between Caspian and Mediterranean ostracods is 0.7, while in the deeper water Site BS 08-055, the abundance ratio between Caspian and Mediterranean ostracods is 0.01. These data argue for the dominance of Mediterranean ostracod fauna with lower abundance in shallower environments of the Black Sea and with a very high abundance in the deeper parts of the internal shelf, i.e., at a water depth of 66 m. Based on the calcareous nannoplankton fluctuation, four Nannofloral Intervals were identified, which indicate a gradual salinity increase of the surface waters during the deposition of the Late Holocene Shallow Unit. In the same interval, the benthic microfaunas (ostracods and foraminifers) argue for a more stable salinity environment in the two studied cores from the Black Sea inner shelf [ABSTRACT FROM AUTHOR]

The relation between the grain size composition TOC (total organic carbon) concentration was examined by linear and non-linear regression analysis of analytical data for more than 500 sediment samples from the NW Black Sea. A significant dependency of the TOC concentration on the percentages of clay and especially the <16 μm fraction (clay plus fine and very fine silt) was identified, the model best fitting the analytical data being exponential. Three groups of sediment samples were identified using the K-means clustering technique, the deep sea sediment samples being clearly singled out. [ABSTRACT FROM AUTHOR]

The investigations focused on two profiles from the Black Sea, placed in front of the Portiţa Mouth and in the south-eastern part of the Sahalin Island. Up to 40 m water depth, the samples from the Portiţa profile contain only reworked Mesozoic and Cenozoic calcareous nannoplankton taxa. In the same profile, the bloom of the calcareous nannoplankton species Emiliania huxleyi, together with abundant benthic foraminiferal taxa, were recorded in the first 11 cm of sediments, at below 40 m water depth. All the samples collected in the SE of Sahalin Island contain only Mesozoic and Cenozoic reworked calcareous nannoplankton taxa; no marine assemblages in situ were remarked. [ABSTRACT FROM AUTHOR]

The paper is based on grain size analyses as well as on the macroscopic lithologic description of a large number of samples collected from the bottom of the Danube. Unlike previous papers on sedimentology, which were limited to the textural characterisation of sediments from the various sectors of the Danube, this paper attempts a new approach of the sediment dynamics. The interpretation of histograms, of cumulative curves or of the Passega diagram is used in the attempt to explain the dynamic and genetic reasons for the presence of a particular type of sediment in locations characterised by different environmental energy conditions. [ABSTRACT FROM AUTHOR]

The article offers information on the European Multidisciplinary Seafloor and water-column Observatory (EMSO), a large-scale European Research Distributed Infrastructure of the European Strategy Forum on Research Infrastructures roadmap with the objective of real-time, long-term monitoring of environmental processes. Topics include the implementation of the project, the participating countries, the EMSO design, and how the research data will be collected and used.

To get more data on the geochemistry of Black Sea euxinic sediments, a 50-cm core was collected at a depth of 600 m on a Western Black Sea Continental Platform slope. The core contained unconsolidated sediments rich in cocoolithic ooze and mud. Epithermal Neutron and Prompt Gamma Activation Analysis were used to determine the content of nine major (Na, Mg, Al, Si, K, Ca, Ti, Mn, and Fe as oxides) and 32 trace elements (Cl, Sc, V, Cr, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Sn, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Hf, Ta, W, Th, and U) with a precision varying between 3 and 9%. The core contained unconsolidated sediment rich in coccolithic ooze and mud. Previous 210 Pb geochronology suggests an age of ∼1 ky of considered sediments. Major components distribution showed that, except for Cl and Ca, the contents of all other elements are similar to Upper Continental Crust (UCC) and North American Shale Composite (NASC). The distribution of the 32 trace elements showed similarities to the UCC, except for redox-sensitive metals Fe, Se, Mo, and U, of which the significantly higher content reflects the presence of euxinic conditions during deposition. A chondrite normalized plot of nine rare earth elements indicated a similarity to UCC and NASC, suggesting a continental origin of sedimentary material. [ABSTRACT FROM AUTHOR]

Understanding the natural evolution of a river–delta–sea system is important to develop a strong scientific basis for efficient integrated management plans. The distribution of sediment fluxes is linked with the natural connection between sediment source areas situated in uplifting mountain chains and deposition in plains, deltas and, ultimately, in the capturing oceans and seas. The Danube River–western Black Sea is one of the most active European systems in terms of sediment re-distribution that poses significant societal challenges. We aim to derive the tectonic and sedimentological background of human-induced changes in this system and discuss their interplay. This is obtained by analysing the tectonic and associated vertical movements, the evolution of relevant basins and the key events affecting sediment routing and deposition. The analysis of the main source and sink areas is focused in particular on the Miocene evolution of the Carpatho-Balkanides, Dinarides and their sedimentary basins including the western Black Sea. The vertical movements of mountains chains created the main moments of basin connectivity observed in the Danube system. Their timing and effects are observed in sediments deposited in the vicinity of gateways, such as the transition between the Pannonian/Transylvanian and Dacian basins and between the Dacian Basin and western Black Sea. The results demonstrate the importance of understanding threshold conditions driving rapid basins connectivity changes superposed over the longer time scale of tectonic-induced vertical movements associated with background erosion and sedimentation. The spatial and temporal scale of such processes is contrastingly different and challenging. The long-term patterns interact with recent or anthropogenic induced modifications in the natural system and may result in rapid changes at threshold conditions that can be quantified and predicted. Their understanding is critical because of frequent occurrence during orogenic evolution, as commonly observed in the Mediterranean area and discussed elsewhere. [ABSTRACT FROM AUTHOR]

Summary: In this work, an interferometric ALOS PalSAR dataset acquired between 2007 and 2010 is used to measure water level changes for the first time within a hydrographical unit of the Danube Delta in Romania at the Black Sea. When the Differential Synthetic Aperture Radar Interferometry (DInSAR) technique was applied, it revealed a previously unknown and spectacular dynamic of the water levels in Danube Delta. The results are presented in the form of water level change maps for different periods of time. The DInSAR measurements for a number of locations are compared with extrapolated water level change values obtained from an existing mathematical model of the hydrological regime in the Danube Delta. The comparison shows a very good correlation between DInSAR measurements and the mathematical model, showing that this method using L-band ALOS PalSAR data and applied to a wetland area of Danube Delta can be used to increase the spatial density of water level measurements and contributes to a better understanding of hydrological processes. [ABSTRACT FROM AUTHOR]