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Inorganic geochemical records of local palaeoenvironmental variability in the Jaworki Formation (Upper Cretaceous) of the Niedzica Succession, Pieniny Klippen Belt (Western Carpathians)

100%

Wójcik-Tabol P.

tom Vol. 131

269-280

The Cenomanian sequence of marls and marly shales interbedded by black shales (Jaworki Formation) from the Niedzica Succession was investigated. These organic carbon-rich horizons may correspond to the event of global anoxity OAE 1d. Major and trace element profiles mirror changing environments of deposition of black shales. In black shales, the content of SiO2, Al2O3, Fe2O3, K2O, TiO2, P2O5 increases at the expense of CaO. All samples are characterised as mixtures of terrigenous- detrital matter with varying amount of calcium carbonate. A good correlation between SiO2, Al2O3, K2O, TiO2, and the correlation with the minor elements Zr, Rb and Nb, point to the detrital origin of these elements. Detrital input was rather scarce. The high trace element/Al ratios in the black shales can be explained either by the adsorption onto organic matter or through the sulphides precipitation. Some black shale-samples are poorer in transitional metals. The studied sediments were deposited under oxic/suboxic conditions interrupted by irregular anoxic periods resulted from expansion of oxygen minimum zone (OMZ).

Geochemical Analysis of Coastal Sediments near Larache and Moulay Bousselham, Morocco

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El Idrissi S. , Labriki A. , Sadiki M. , Akhlidej N. , Bounouira H. , Said S. , Amsil H. , Didi A. , Aarab I. , Chakiri S.

2024

tom Vol. 25, iss. 8

221--231

The aim of this study is to identify the main pollutants and evaluate the mechanisms of sediment transport from land to sea. This goal is justified by environmental pollution in the area associated with dredging and port activities. The objective is planned to be achieved by investigating the geochemical behavior of major and trace elements in fourteen surface sediment samples collected along the Moroccan Atlantic coast, from the mouth of the Lukkous River to the coast between the cities of Larache and Moulay Bousselam. k0-standardization method of neutron activation analysis using neutrons of the Moroccan Triga Mark II research reactor at the National Centre for Nuclear Energy, Science and Technology, has been used for analysis of collected sediment samples. The enrichment factor analysis revealed high levels of arsenic and chlorine, along with significant calcium enrichment, were found along the Atlantic coast. The enrichment factors (FE) for arsenic and chlorine are in the range of 20 < FE < 40, and for calcium, the FE is in the range of 5 < FE < 20. Conversely, some elements exhibited little to no enrichment, suggesting a crustal origin. PCA helped in synthesizing these findings, providing a clearer understanding of the spatial variations in sediment composition based on their multi-elemental signatures. The research examines surface sediments along the Moroccan Atlantic coast, revealing current contamination levels and geochemical behavior. These findings, applicable to similar coastal environments, are crucial for monitoring and managing sediment quality, especially in areas affected by erosion. Additionally, dredging and port activities in this region significantly disturb the sediments, resuspending contaminants and altering sediment composition, which further exacerbates pollution issues. This study offers a comprehensive geochemical characterization of coastal sediments in Morocco, enhancing understanding of sediment contamination and geochemical processes, with implications for environmental protection and sustainable marine resource management.

Dependences Between Certain Petrographic, Geochemical and Technological Indicators of Coal Quality in the Limnic Series of the Upper Silesian Coal Basin (Uscb), Poland

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Parzentny H. R. , Róg L. , Parzentny H. R. , Róg L.

nr 3