This research is focused on the determination of the heavy minerals (HM) load of the Vjosa and Mati river delta deposits along the Albanian coastline and it is based on X-ray Diffractometry. The Albanian coastline consists of sandy beaches at the north (Adriatic coastline) and rocky escarpments at the south (Ionian coastline). Several layers of heavy mineral deposits, up to 50 cm thick, with heavy mineral fraction up to 95% and 88% of total sample for Vjosa and Mati sediments respectively, are identified. The layers enriched in heavy minerals from Vjosa delta deposits are almost black in colour, while at Mati delta these layers are dark green coloured. Separation of the heavy from the light fraction was performed, in order to compare the different fractions between the two studied delta areas. The accumulation of HM occurs mainly in the fraction of 125-250 µm in the sediments of both deltas. The HM dominate in the magnetic field of 0.4-0.8 A/m. XRD analysis results show a great variety of minerals present in the delta samples which can be attributed to the wide variety of geological zones and lithologies that are intersected by the Vjosa and Mati rivers, respectively. In the 63-425 μm fraction rich in heavy minerals of both delta systems considerable amounts of magnetite (up to 39.4% in Vjosa samples), chromite (up to 20.2% in Vjosa samples), garnet (up to 13.6% in Vjosa samples), ilmenite (up to 8.3% in Mati samples), rutile (up to 4.7% in Mati samples), hematite (up to 2.2% in Mati samples), and zircon (up to 2.1% in Vjosa samples) are observed. Rock forming minerals such as pyroxene, amphibole, and epidote compose significant percentages of this fraction. In addition, the presence of gold grains in Vjosa delta sediments is remarkable. Both catchment areas consist to a great extent of similar formations such as the Mirdita Ophiolite Zone and the Pindos Ophiolite complex, providing thus a similar HM fingerprint at both delta areas. Minerals that occur in higher abundances reflect the extensive presence in the drained areas of related parent rocks which are rich in these minerals and which are often more vulnerable to weathering. The samples of Vjosa river delta show high percentage of carbonate constituents, which is related to the presence of carbonate rocks of the Ionian and Kruja tectonic zones within which the hydrographic network of the Vjosa River has been developed. The samples of Mati river delta show lower abundance of carbonate minerals, reflecting the limited presence of carbonate rocks at the Kruja Zone, which occur in the catchment area of the river near its mouth.
Vjosa River sources from Pindus Mountains in Greece, with a length of 272 km and drains in the southern of Albania. The surface of Vjosa river drainage basin is 6700 km 2. The surface of the river delta is 317 km 2 , and stretches from Hoxhara channel in the north to the Zvërnec molasses hills in the south. The study area is characterized by sandy banks, mud flats, salt marshes, small lagoons, and temporary marshes. This delta presents a coastal area up to 12.6 km toward the south and 9.5 km in the north. For the analysis of the grain size distribution and sediment parameters such as mean, standard deviation or sorting, skewness and kurtosis of Vjosa river delta a Laser diffraction Analysis was applied. The measurements were performed using a Malvern instrument while the data processing was carried out by Mastersizer 2000 software. The bivariate analysis, linear discriminant functions (LDF), passega diagrams (CM plots) were used for 50 samples, in order to study the depositional processes, hydrodynamic conditions, mechanism of sedimentation and depositional environments. The results show that samples of the Vjosa river delta consist of fine to medium sand, well sorted, near symmetrical, mesokurtic to very leptokurtic. The linear discriminant functions analysis indicates that sediments were reworked by Aeolian and Beach processes under the environment of shallow marine and fluvial deposits. Results of passage diagrams (CM plot) reveal that sediments were deposited by bottom suspension and rolling-PQ and less graded suspension-QR, as well as rivers and by tractive currents.
For the determination of the heavy minerals composition of the Vjosa River Delta deposits and characterization of the granulometry of samples taken in littoral, X-ray Diffractometry technique and Laser Diffraction Analysis (LDA) were used. The Vjosa River delta stretches from Hoxhara channel, at the north, to molasses hills of Zvërnec in the south, forming a littoral of about 22km. Two old river mouth are identified, one in the south, near to Narta lagoon, and one in the north of the actual delta, which is related to the position of current Hoxhara artificial channel. Related to the hydraulic elaboration of shoreline sediments, several layers of heavy mineral deposits, up to 50 cm thick, with heavy mineral fraction up to 90% of total sample are identified. XRD analysis reveals a large variety of heavy minerals present in these sediments. Chromite and magnetite are the main components of the heavy fraction. Occasionally, accumulations of garnets (up to 13.6%), zircon (up to 2%), rutile (up to 3.8%) and ilmenite (up to 3.8%) are also observed. Rock forming minerals as pyroxenes, amphibole, olivine and epidote compose the rest of the samples. LDA analyses indicate that Vjosa delta sediments consist on fine to medium granulometry, well sorted to moderately well sorted sands, symmetrical to fine skewness, with mesokurtosis to very leptokurtic distribution.
Vjosa River is the most important river of southern Albania, also is one of Europe's wild rivers, with a length of 272 km and drainage basin of 6706km 2 . It sources from the Pindus Mountains in Greece (where it is called Aoös River) and drains in Albanian coast, near to the Narta Lagoon. Delta of Vjosa River with a surface of 317 km 2 is characterized by intensive changes of the shoreline, affected by the wave activity of the Adriatic Sea mostly affecting the river mouth and abandoned channels. The geometry and geomorphology of this delta has been conditioned by tectonic orientation of the Panaja and Frakulla neogene molasses hills. Study of the coastal dynamic and geometry changes of the delta mouth has been reconstructed using the information of topographic maps of Albania from existing studies and reports as well as the information extracted from satellite images. The statistical calculation of erosion and depositional are performed using GIS software technology. The studies performed on dynamics, erosion and accumulation, changes of the mouth shapes and coastline movements lead to the conclusion that delta area of Vjosa River is continuously in evolution. During the period from years 1870 to 2016, the interaction of sedimentological and neotectonic processes lead to total accumulation of an area of 21.7 km 2 , while an erosion surface of 7.5 km 2 is developed mostly at the southern river mouth.
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