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Tirana, Albania

Morellon M.,Complutense University of Madrid | Morellon M.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Anselmetti F.S.,University of Bern | Ariztegui D.,University of Geneva | And 6 more authors.
Quaternary Science Reviews

Lake Butrint (39°47 N, 20°1 E) is a ca. 21 m deep, coastal lagoon located in SW Albania where finely-laminated sediments have been continuously deposited during the last millennia. The multi-proxy analysis (sedimentology, high-resolution elemental geochemistry and pollen) of a 12 m long sediment core, supported by seven AMS radiocarbon dates and 137Cs dating, enable a precise reconstruction of the environmental change that occurred in the central Mediterranean region during the last ~4.5 cal kyrs BP. Sediments consist of triplets of authigenic carbonates, organic matter and clayey laminae. Fluctuations in the thickness and/or presence of these different types of seasonal laminae indicate variations in water salinity, organic productivity and runoff in the lake's catchment, as a result of the complex interplay of tectonics, anthropogenic forcing and climate variability. The progradation of the Pavllo river delta, favoured by variable human activity from the nearby ancient city of Butrint, led to the progressive isolation of this hydrological system from the Ionian Sea. The system evolved from an open bay to a restricted lagoon, which is consistent with archaeological data. An abrupt increase in mass-wasting activity between 1515 and 1450 BC, likely caused by nearby seismic activity, led to the accumulation of 24 homogenites, up to 17 cm thick. They have been deposited during the onset of finely laminated sedimentation, which indicates restricted, anoxic bottom water conditions and higher salinity. Periods of maximum water salinity, biological productivity, and carbonate precipitation coincide with warmer intervals, such as the early Roman Warm Period (RWP) (500 BC-0 AD), the Medieval Climate Anomaly (MCA) (800-1400 AD) and recent times (after 1800 AD). Conversely, lower salinity and more oxic conditions, with higher clastic input were recorded during 1400-500 BC, the Late Roman and the Early Medieval periods (0-800 AD) and during the Little Ice Age (1400-1800 AD). Hydrological fluctuations recorded in Butrint are in phase with most central and western Mediterranean records and correlate with NAO variability. In contrast, opposite hydrological patterns have been recorded in the Eastern Balkans and the Levant during the last millennium, emphasizing a complex spatial variability in the region. Phases of maximum settlement intensity in Butrint (Roman-Late Antique) coincide with warmer and/or stable climate periods (0-800 AD and MCA, respectively), indicating a long-term influence of climatic conditions on human activities. The Late Holocene sedimentary record of Lake Butrint demonstrates the complex interplay of climate variability, tectonics and human impact in the recent evolution of coastal Mediterranean regions. © 2015 Elsevier Ltd. Source

Kumanova X.,Albanian Geological Survey | Leka G.,Albanian Geological Survey | Nilsson B.,KTH Royal Institute of Technology | Jacks G.,KTH Royal Institute of Technology
Environmental Earth Sciences

The transport of metals was investigated at 15 sites in the River Fani and the River Mati in N. Albania. There are numerous abandoned copper mine sites and one active mine upstream in the River Fani catchment. Upstream in the Mati catchment, there is a large chromium smelter and several chromium mines. Water samples and sediment samples were collected at all the sites. Moreover, the water samples at a number of the sites were fractionated by filtering and by dialysis to assess in which form the metals were transported. There was a relatively larger abundance of metals in the suspended (unfiltered water) and colloidal phases (filtered by 0.2-μm filters). Metal concentrations in water and in sediments decreased rapidly downstream away from point sources, approaching background levels within 10 km, indicating that the larger fractions could settle in the sediments. The River Mati recharges a large coastal aquifer via an alluvial fan at the entrance into the coastal plain. There does not seem to be any risk of metals appearing in the groundwater, as the transport mode is that of largely suspended and colloidal matter. The offshore metals in the Adriatic Sea are likely to be flushed out during rainy seasons with high discharge. The bioavailability of the metals is likely to be low except for just downstream of point sources. In view of the relatively large fractions of metals found in the suspended and colloidal phases, the establishment of sedimentation basins downstream point sources would decrease the export to the rivers. © 2015, Springer-Verlag Berlin Heidelberg. Source

Savini A.,University of Milan Bicocca | Corselli C.,University of Milan Bicocca | Durmishi C.,Albanian Geological Survey | Marku S.,Albanian Geological Survey | And 2 more authors.
Journal of Coastal Research

The present work reports the main results obtained from recent seafloor-mapping activities carried out offshore from south-western Albania. The area explored consists of two distinctive physiographic units: the Vlora Gulf (which is bounded to the west by the Karaburun Peninsula) and the upper continental slope offshore from the western side of the Karaburun Peninsula. Along these areas, 500 km 2 of multibeam echo-sounder coverage, about 2500 km of chirp-sonar data, and 200 km 2 of side-scan sonar mosaic (100-500 kHz) were acquired. This new acoustic data set was collected by two different oceanographic expeditions, which were carried out in the framework of the Centro Internazionale di Scienze del Mare (CISM) project (supported by Interreg III Italia-Albania), which focused on studying, through a multidisciplinary approach, the geological setting and the ecosystem conditions of a poorly investigated area of the Adriatic Sea, such as the Vlora Gulf. The investigated area incorporates water depths measurements from 5 m down to 57 m, whereas the offshore margin of the Karaburun Peninsula has been investigated down to 900 m water depth. The acquired high-resolution multibeam bathymetry, combined with the described chirp-sonar echo-types, documents how the recent evolution of the Vlora Gulf is strictly dependent on complex, sedimentary dynamics established in this area. Here, the Vjose River is the dominant source of sediment for the continental shelf. We provided evidences that the (Vjose River) sediment distribution is under the control of a complex, local circulation pattern that is defined by the peculiar regional shape of the gulf which is tectonically controlled. The tectonic control on the present-day, sedimentary processes is also evident offshore from the Karaburun Peninsula, along the upper slope, where important resedimentation processes have been recognized and are related to the recent geodynamic evolution of the margin. © 2011 Coastal Education and Research Foundation. Source

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