Listvenitization of Neoproterozoic ophiolitic serpentinites and formation of gold-bearing listvenites in the Mueilha-Dungash area, Eastern Desert of Egypt, Arabian-Nubian Shield

The ophiolitic sequence exposed in the Mueilha-Dungash area, Egypt represents a fragmented Neoproterozoic ophiolite within the northern Arabian-Nubian Shield. Serpentinites are the dominant lithology and preserve fresh relics of primary minerals such as olivine, orthopyroxene, and Cr-spinel. These serpentinites are extensively altered, giving rise to listvenites, rodingites, talc‑carbonate rocks, and magnesite veins. Listvenites, which consist of varying proportions of magnesite and quartz, occur as dyke-like bodies or lenses and are subdivided into carbonate-rich listvenite, quartz‑carbonate listvenite, and quartz-rich listvenite (birbirite). The carbonate-rich listvenite formed early, pre-dating obduction but post-dating serpentinization, through infiltration of externally derived CO₂-rich fluids. Following obduction, quartz‑carbonate listvenite developed through influx of hydrothermal, crustally derived SiO₂-rich fluids circulating during ophiolite emplacement. Birbirite represents the latest stage, formed by silicification of pre-existing listvenites. This progressive listvenitization is associated with notable enrichment in precious metals, particularly gold, in the quartz‑carbonate samples. ... mehrThe gold content increases in tandem with elevated concentrations of Zn, As, Cu, Ag, and Pb, suggesting a shared source and fluid pathway for these elements.