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Exploring the economic significance and diverse hues of quartz: A case study at Adaila, south of El Ma Labiod, NE Algeria

Nacer Wassila, Defaflia Nabil, Taib Hassan, Rehebi Rofaida

Geomatics, Landmanagement and Landscape

2024

no. 1

117--133

The Tebessa region in Algeria is rich in mineralogical resources within its Quaternary deposits, particularly in quartz. This study adopts a multidisciplinary approach including stratigraphic, sedimentological, and granulometric analyses, focusing specifically on the deposits located in the fluvial terraces of the Oued Adaila, south of Tébessa in eastern Algeria. The analysis of granulometric parameters gave valuable insights into the uniformity of the energy levels exerted by the transport agents. Pioneering exoscopy techniques have proved indispensable in discerning the sedimentary history of quartz, offering comprehensive insights into its weathering processes and its intricate journey through continental aquatic pathways. Additionally, this methodology has elucidated the genesis of unique colourations observed in quartz grains. Using Scanning Electron Microscopy (SEM), we have examined the surfaces of quartz grains, revealing an array of patterns attributable either to the inherent crystal lattice structure of quartz or to the erosive influences of the changing environment. These environmental modifications stand out as the primary contributors to the diverse spectrum of colours manifested in the quartz grains. Furthermore, the examination of magnetic data has highlighted the pivotal role played by various oxides present in the Quaternary deposits. These oxides proved to be important sources of ferric elements, crucial in imparting the distinct colorations observed in quartz. This comprehensive study significantly advances our understanding of the mineralogical constitution, sedimentary evolution, and the environmental dynamics shaping the Quaternary deposits in the Tebessa region.

Wybrane problemy związane z powstawaniem piaszczysto-żwirowych form dennych w ujściowym odcinku rzeki podgórskiej

Radecki-Pawlik A.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

2008

Vol. 17, No. 2

98--116

In the paper the research results of forming observations of sand-gravel dunes developing on the riverbed along the outlet reach of the highland type of river. The subject of subaquatic river forms one can find in many scientific works, however most of the existing papers cover sand dunes and ripples found in the lowland rivers. Moreover, the majority of research was conducted in laboratory flumes, since all fieldworks need very complex research, complicated logistic as well as is extremely money consuming (hiring ships, diving bell, long time echosounding etc.). Thus there is a nowadays need to present field data covering a subject of the river bed forms which still could be considered as dunes but are built up with material coarser then 2 mm (which is fine gravel) and coarser. The research reach described along the present paper is lying in the region of confluence of the Raba and the Vistula Rivers, within the outlet of the Raba River, close to Uscie Solne, just below the Polish Carpathians mountains line. The research results show such parameters as: length, height and granulometric composition of the dunes found along that reach as well as the hydrodynamics parameters such as: shear velocity, shear stresses and resistant coefficients. Having gathered in one place the field measurements results many relationships between mentioned parameters are presented. The work could be useful for river engineers, fluvial geomorphologists, geologists and ecologists working with river channels.