Geochemical and Mineralogical Characterization of Recent Coastal Sediments in the Gabes Region, Eastern Libya: Implications for Marine Depositional Processes and Environmental Change
DOI:
https://doi.org/10.63359/g1ph7j18Keywords:
Gabes, Calcite, beach sand, Calcarenite RocksAbstract
This study provides a comprehensive geochemical and mineralogical analysis of recent coastal sediments in the Gabes region, located east of Tobruk, Libya. The region is predominantly composed of sandy terrain with calcarenite beds, characteristic of recent sedimentary formations. Six samples were collected from various geomorphologic units along the Gabes coastline, including beach sands and coastal rocks, and analyzed using X-ray diffraction and petrographic techniques. The analysis revealed significant mineralogical variations between coastal rocks and beach sands. Coastal rocks are predominantly composed of aragonite (50.4% to 63.6%) and high-Mg calcite (23.5% to 47.5%), indicative of marine biogenic processes. The minimal quartz content suggests a limited terrestrial influence, emphasizing a primarily marine depositional environment. In contrast, beach sands exhibited higher variability, with aragonite ranging from 36.6% to 61.6% and quartz content reaching up to 18%, indicating a mixed depositional environment influenced by both marine and terrestrial inputs. Notably, one sand sample contained 2.2% halite, reflecting localized evaporitic conditions. These findings underscore the complexity of depositional and diagenetic processes in the Gabes region, with the coastal rocks shaped predominantly by marine influences and the beach sands reflecting a dynamic interplay between marine and terrestrial sources. The study contributes to our understanding of sedimentary processes in the Mediterranean coastal region, offering valuable insights into past and present environmental changes in northeastern Libya.
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