The present study was conducted to highlight the elemental composition of ten soil samples collected at different depths along of a soil profile (0.25-17 m). The collected samples were subjected to epithermal neutron activation analysis at the pulsed reactor IBR-2 of Frank Laboratory of Neutron Physics - Joint Institute for Nuclear Research - Dubna - Russian Federation. The concentrations in mg/kg of 36 major and trace elements were determined. Symbatic behaviour of geochemically related elements was observed: Th and U; Cl and Br and Fe, Ti, Ca, Al, and Mg, etc. A sharp increase of certain concentrations at the depth of 8 m was observed. Significant mafic sources of elements were observed and mostly are attributed to Ethiopian High Plateau with small amount of felsic volcanic rocks.
The aim of the study was to assess the content of Ca, Mg, Na and K in the road dust collected in Białystok from various environments (roads with high traffic intensity, housing estate roads, roads located near parks and green areas), in order to determine the impact of the road transport on the spatial differentiation of the content of the tested components in street dust and identify their main sources. In total, the samples from 69 points were analyzed, which were taken in spring 2018 (late April and May) during the dry weather. The content of Ca, Mg, Na and K was determined by means of atomic absorption spectrometry (AAS). The average contents of the tested elements in the dust from all measuring points were in the following order: Ca (23.53%) > Mg (2.38) > Na (1.16) > K (0.25). This shows that Ca is the most numerous element in the tested dusts. Studies have not shown a significant impact of vehicle traffic, in particular the so-called non-exhaust sources related to this traffic on the content of main elements in the Białystok road dusts. The analyses have indicated that the main source of Ca and Mg in the Białystok road dust constitute the structural elements of roads, bridges and structures, in which building cement and its derivatives are the main component.
Tectonic setting of both the uppermost Triassic Tomanová and the lowermost Jurassic Dudziniec formations can be characterized by a series of diagnostic discrimination diagrams. High-silica and low-silica multi-dimensional diagrams indicate that the sediments could have been deposited in the continental collision/rift setting. Diagrams of K2O/Na2O versus SiO2, SiO2/Al2O3 versus K2O/Na2O and Th-Co-Zr/10 as well as Th-Sc-Zr/10 determine an origin from the tectonically active and/or passive continental margin setting. REE parameters indicate predominantly a passive margin tectonic setting of the sediments. The most probable source of clastic admixture in the Scythian to Domerian sediments in the Tatric Unit was situated in a remnant of the Variscan collisional orogen - the Vindelician Highlands. Occasional monsoonal rains occurring in orbitally controlled cycles transported weathered material from the source area down river valleys on the seaward slopes of the Variscan Vindelician Mountains towards the Tethyan Sea. The input of this material influenced also the marginal parts of the Fatricum (e.g., Vysoká or Havran units).
Béchar region is located in the southwest of Algeria, characterized by an arid climate with a Saharan tendency. It is subject to an increasing demand for water like all the great agglomerations due to the economic and demographic development. The groundwater of region is deteriorating because of the economic development, and the rapid growth of population. This article is devoted to the study of hydrochemistry and processes of mineralization of groundwater in this region. The results of physicochemicals analyses shows the same chemical facies of the chloride and sulphate-calcium and magnesium type, with high mineralization from North-East to South- -West to the outlet of Béchar–Kénadsa basin. The determination of the mineralization origin and the main major elements were approached by multivariate statistical treatment and geochemical. This method has identified the main chemical phenomena involved in the acquisition of mineralization of water in this aquifer. These phenomena are mainly related to the dissolution of evaporite formations, the infiltration of runoff water and direct ion exchange and mixing. However, the high mineralization anomaly is observed at the centre of Béchar–Kénadsa basin progressively by going to the outlet of this basin.
PL
Region Béchar w południowozachodniej Algierii charakteryzuje klimat suchy z wpływami saharyjskimi. Jak wszystkie duże aglomeracje, region ten wykazuje rosnące zapotrzebowanie na wodę w związku z rozwojem ekonomicznym i demograficznym. Rozwój gospodarczy i szybki przyrost populacji jest powodem pogarszania się jakości wód gruntowych. Niniejszy artykuł jest poświęcony badaniom właściwości hydrochemicznych i procesów mineralizacji wód gruntowych w regionie. Wyniki analiz wykazują występowanie podobnych facji chemicznych typu chlorkowego i siarczanowo-wapniowych lub magnezowych o wysokim stopniu mineralizacji od północnego wschodu do południowego zachodu basenu Béchar–Kénadsa. Źródła mineralizacji i główne pierwiastki zostały oznaczone metodami geochemicznymi z zastosowaniem wieloczynnikowej analizy statystycznej. Metody te dały podstawy do identyfikacji głównych zjawisk chemicznych wpływających na mineralizację wody, takie jak rozpuszczanie formacji ewaporytowych, infiltracja spływów powierzchniowych, bezpośrednia wymiana jonowa i mieszanie. Anomalię wysokiej mineralizacji malejącą w kierunku odpływu zaobserwowano w środkowej części basenu Béchar–Kénadsa.
The Triassic-Jurassic boundary interval (ca. 201 Ma) was a time of sudden global environmental changes triggered by Pangea breakup and Central Atlantic Magmatic Province development. The bulk-rock mineralogy, clay mineralogy and major element geochemistry of 87 continental mudrock samples collected from four borehole cores yield information on Rhaetian-earliest Hettangian palaeoclimatic changes in the Polish Basin. During the Rhaetian, smectite preponderance was replaced by kaolinite and illite domination. This fundamental shift in clay mineral assemblages (supported by major element data) indicates very significant change in climate humidity. Moreover, some beds in the Zagaje Formation (Upper Rhaetian-Lower Hettangian) are particularly rich in kaolinite indicating extreme chemical weathering in humid-subtropical to tropical climate episodes in the aftermath of powerful warming and abundant rainfall. Importantly, the first distinct kaolinite enrichment appears already in the Lower Rhaetian Wielichowo Beds. In addition, abrupt and episodic shifts in the kaolinite-illite ratio and in values of weathering indices point to profound climate destabilisation and a sequence of frequent, catastrophic climatic reversals in the Late Rhaetian and at the Triassic-Jurassic boundary. These results are generally consistent with carbon isotope records in sections worldwide.
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