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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.

Morphotectonic implication of the Paleoproterozoic Mid-Lithuanian Suture Zone

Šliaupa S., Satkūnas J., Motuza G., Šliaupienė R.

Geological Quarterly

2017

Vol. 61, No. 3

590--601

The Paleoproterozoic Mid-Lithuanian Suture Zone represents one of the major structures of the crystalline basement of Lithuania, separati ng the West Lithuanian and the East Lithuanian domains. This zone has shown persistently low tectonic activity during the Phanerozoic. The Mid-Lithuanian Suture Zone is marked by a distinct Middle Lithuanian topographic low underlain by a trough in the sub-Quaternary surface that suggests the morphotectonic nature of this depression. This is supported by high-precision geodetic level l ing data that has unravelled the subsidence trend of the Middle Lithuanian trough. The zone is also distinct in its pattern of topographic lineaments. The persistence of the tectonic activity of the Mid-Lithuanian Suture Zone suggests that it represents a large-scale mechanical boundary of the Earth's crust, resulting in increased accumulation of tectonic strain.

Dating of the Holstejnskä Cave deposits and their role in the reconstruction of semiblind Holśtejn Valley Cenozoic history (Czech Republic)

Kadlec Jaroslav, Hercman Helena, Nowicki Tomasz, Głazek Jerzy, Vit Jan, Śroubek Pavel, Diehl Jimmy F., Granger Darryl

Geologos

2000

Vol. 5

57--64

Large sections in cave deposits are exposed in the Holśtejnska Cave in the Moravian Karst (Czech Republic). The study of the genesis and age of these cave deposits poses a clue to the reconstruction of this cave system and of local paleohydrographic history. The time of deposition was determined by U-series dating of speleothems, 10Be and 26Al dating of quartz pebbles, radiocarbon dating of charcoal, measurement of paleomagnetic record in both clastic sediments and speleothems and by archeological evidence.