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Abstract

In Inner Somogy the former researches concluded that the grain size of stabilised aeolian dunes decreases from north to south fitting to grain size distribution of the alluvial fan the dunes were built of and to the prevailing wind. However, the trend is not so evident, if considering the dune types and sand moving periods. The aim of this paper is to analyse the grain size distribution trends from the point of view of (1) different dune classes, (2) OSL age and (3) general morphological characteristics of the region. During the analysis the grain size distribution of 345 samples from 17 cores (120-300 cm in depth) was determined, and 15 OSL samples were dated. According to the results, the material of simple forms and level 1 dunes (these are the lowest dunes on the surface of the alluvial fan) becomes finer southward, in accordance with the structure of the alluvial fan and prevailing wind direction. Similar trend applies for level 2 dunes (which were formed on the top of level 1 dunes), but it does not apply for level 3 dunes, which are situated on the top of other dunes. It seems that the grain size is inversely proportional to the size of a dune and its age, thus younger and smaller dunes have coarser and less well sorted material. The sediments of the oldest, large parabolic dunes are the finest, younger, medium size parabolic forms have fine material, and the youngest hummocks contain the coarsest sand. The decreasing grain size towards south is the most apparent along longitudinal residual ridges, while within parabolic dunes the wings contain finer material than their elevated head.

diffraction and sedimentation methods. Biosystems Engineering 106, 205-215. Ferro, V., Mirabile, S. 2009. Comparing particle size disturbation analysis by sedimentation and laser diffraction method. Journal of Agricultural Engineering 2, 35-43. Fritsch 2009. Particle sizing - laser diffraction, http://www.benelux-scientific.be/ileadmin/user_files/pdf/poederkarakterisatie/laserd/LASER_DIFFRACTION.pdf, available 2012 - 08-31 Goossens, D. 2008. Techniques to measure grain-size distributions of loamy sediments: comparative study of ten instruments for wet analysis

Introduction The grain size analysis is one of the tests that can be performed to determine the percentage of different grain size contained within the soil. It provides very useful information on the classification of sedimentary environment and the transportation of the sediments. The grain size distribution provides good quantification for soil studies and reveals the weathering characteristics of sedimentary processes and provenance [ 1 , 2 , 3 , 4 ]. The results of Abuodha [ 5 ] have helped to clarify the sedimentary environment and its transport dynamism

in the significance of grain size parameters. Journal of Sedimentary Petrology 27, 2-26. DOI: 10.1306/74d70646-2b21-11d7-8648000102c1865d Forde, J., Collins, P.C., Patterson, A., Kennedy, R. 2012. Comparison of granulometric methods and sampling strategies used in marine habitat classification and Ecological Status assessment. Marine Pollution Bulletin 64, 1018-1028. DOI: 10.1016/j.marpolbul.2012.01.036 French, H.M. 1996. The Periglacial Environment, Harlow: Addison Wesley Longman, 2nd ed., 341 p. Goossens, D. 2008. Techniques to measure grain-size distributions of

References Allen, G.P., Castaining P., Klingebiel, A., 1972. Distinction of elementary sand population in the Gironge estuary (France) by r-mode factor analysis of grain size data. Sedimentology 19, 21-35. Asselman, N.E.M., 1999. Grain-size trends used to assess the effective discharge for floodplain sedimentation, river Waal, The Netherlands. Journal of Sedimentary Research 69, 51-61. Blott, S.J., Pye, K., 2001. Gradistat: A grain size distribution and statistics package for the analysis of unconsolidated sediments. Earth Surface Processes and Landforms 26

sensing in fluvial environments. Earth Surface Processes and Landforms 31, 1413-1423. Casagli, N., Ermini, L. & Rosati G., 2003. Determining grain size distribution of the material composing landslide dams in the Northern Apennines: sampling and processing methods. Engineering Geology 69, 83-97. Church, M.A., McLean, D.G. & Wolcott, J.F., 1989. River bed gravels: sampling and analysis. [In:] C.R. Thorne, J.C. Bathurst & R.D. (Eds): Sediment transport in gravel-bed rivers. Wiley, Chichester, 43-88. De Vries, M. 1970. On the accuracy of bed-material sampling

parameters of sediments as a result of wind activity. Barchans Jarangiyn els in Gobi, Mongolia. Misceallanea Geographica 11, 81-91. Racinowski, R., Szczypek, T., & Wach J., 2001. Prezentacja i interpretacja wyników badań uziarnienia osadów czwartorzędowych [Presentation and interpretation of the grain-size distribution of Quaternary sediments]. University of Silesia Press, Katowice 146 pp. Rizzetto, F., Mycielska-Dowgiałło, E. & Castiglioni, G.B., 1998. Some aeolian features in the Po plain near Este (North Italy). Geografia Fisica e Dinamica Quaternaria 21, 245

using airborne digital imagery. Water Resources Research 40, W07202, DOI: 10.1029/2003WR002759. Chang, F.J., Chung, C.H. 2012. Estimation of riverbed grain-size distribution using image-processing techniques. Journal of Hydrology 440-441, 102-112. DOI: 10.1016/j.jhydrol.2012.03.032 Dietrich, W. E., Whiting, P. 1989. Boundary shear stress and sediment transport in river meanders of sand and gravel. In: Ikeda, S., Parker G. River meandering: American Geophysical Union Water Resources Monograph 12, 1-50. Dykaar, B. B., Wigington, P. J. 2000. Floodplain formation and

Comparative analysis of the geotechnical properties of coal mining wastes from Lublin Coal Basin and from other basins

There are 40 coal mines in Poland now. One of them (coal mine "Bogdanka") is situated in Lublin Coal Basin, other are localised in Silesia and Małopolska regions. Coal mining is a source of large amounts of wastes. Mean annual production of wastes in only Lublin Coal Basin exceeds 2 million Mg, 65% of which is disposed on a heap. The rest is used to restore opencast excavations, to construct and repair local roads and to produce building materials. It seems that large amount of these wastes could be used to construct or modernize flood embankments and dykes. Using mine wastes as building materials requires the knowledge of their geotechnical parameters. A characteristic feature of mine wastes is their gradual weathering which affects geotechnical parameters largely determined by their mineral and petrographic composition.

This paper describes analyses of geotechnical parameters of mine wastes from Lublin Coal Basin (heap near coal mine Bogdanka") of various storage times and of samples collected after 10 years of exploitation of a dyke between ponds made of these wastes at the break of 1993 and 1994. Detailed analyses involved: grain size distribution, natural and optimum moisture content, maximum dry density, shear strength and coefficient of permeability. Obtained results were compared with literature data pertaining to mine wastes from Upper Silesian Coal Basin and from other European coal basins.

Performed studies showed that coal mining wastes produced in Lublin Coal Basin significantly differed in the grain size distribution from wastes originating from Upper Silesian Coal Basin and that weathering proceeded in a different way in wastes produced in both sites.

Abstract

The paper presents measurements of the amount, spatial distribution, grain size structure, density and the content of organic matter in sediments of Suchedniów reservoir. After 33 years of exploitation, the primary volume of the reservoir decreased by 78 thousand m3. Catchment area covered in 45% by forests is 83 km2. Mean annual water flow is estimated at 0.63 m3·s-1. Primary volume of the reservoir was 303 thousand m3 and its surface area - 21.4 ha. The greatest width of the reservoir is 490 m, distance from the river inlet to the dam is 655 m and the length along assumed water course is 740 m. Mean and maximum depths are 1.42 and 4 m, respectively.

The analyses of vertical and horizontal distribution of sediments revealed that in the deepest parts of the water body, where depth exceed 2.6 m, only 16% of sediment volume were deposited. In the inlet part of a relative volume of 0.2, 32% of sediment volume were deposited and in the outlet part - 16%. The reservoir accumulates material of a grain size <1.0 mm whose density varies between 2586 and 2758 kg·m-3. Percent of organic parts in sediments ranged from 0.24 to 18.97%.

The existing methods of description of sediment distribution in retention reservoirs do not allow for accurate predicting of this distribution. They do not account for many factors affecting the distribution of sediments in reservoirs and for the time of exploitation. None of the dimensionless curves of the Annandale’s nomograph [ANNANDALE 1984] describes the distribution of sediments in Suchedniów Reservoir. The curve closest to the actual distribution curve corresponds to the value dP/dx = 1.2 while for Suchedniów Reservoir dP/dx is 0.0014 (P - wetted perimeter of the reservoir’s cross section, x - distance from the dam). Sediments in vertical profiles have laminar structure and bottom material in layers largely differs in grain size and colour which is an evidence of different conditions of sedimentation in different hydrological periods and exploita