Investigation of Sedimentary Microfacies and mineralogical analyses of the Coastal Rock Cliffs (Wadi al-Zaytoun) in the Al Jaghbub, Al Faidyah, and Abraq Formations, NE Libya
DOI:
https://doi.org/10.37375/sjfssu.v5i1.3080Keywords:
Wadi al-Zaytoun, Minerals, Facies, Dolomite and ForaminiferaAbstract
This study analyzes the bulk mineralogy and microfacies of the Al Jaghbub, Al Faidyah, and Abraq Formations, NE Libyaalong the Eastern Libya coastline using X-ray diffraction (XRD) on five samples from different geomorphological units. The results show a dominance of terrigenous minerals—mainly quartz, albite, and kaolinite—alongside carbonate minerals (calcite and dolomite) and evaporite minerals, particularly halite. Quantitative analysis reveals significant mineral proportion variations Al Abraq Formation contains high levels of dolomite (87.9%) and albite (7.9%), while Al Faidiyah Formation is predominantly calcite (98.9%). Halite appears in All Formations, indicating evaporative processes, and kaolinite in Sample 3 suggests fluvial influence or older sediment reworking. Microfacies analysis, conducted on thin sections from Wadi al-Zaytoun, identified five types: (1) dolomite wackestone, (2) foraminiferal bioclast packstone, (3) dolomitic wackestone, (4) foraminiferal bioclastic packstone, and (5) echinoidal, foraminiferal, algal packstone.
These microfacies display features indicating deposition in various environments, ranging from arid tidal flats to high-energy shallow marine settings. Diagenetic processes such as the replacement of micritic matrices with sparry calcite and the formation of coarse dolomite crystals highlight the roles of fluid migration and redox fluctuations.
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