Geometry of Middle Miocene Carbonates in the Red Sea: Outcrop Analogues for Fault-Block Carbonate Platforms in Rift Basins

Abstract This study investigates Middle Miocene carbonate platform outcrops along the Arabian margin of the Red Sea. These platforms, formed on footwalls of major rift faults, serve as analogues for fault-block carbonate reservoirs. The study focuses on platform geometry, facies distribution, and diagenetic features, which are relevant for exploration models and reservoir characterization. The study integrates field observations, satellite imagery, and stratigraphic analysis across an 800 km stretch of coastline. The platforms are dated to the Late Burdigalian to Early Langhian (16-14 Ma) and rest unconformably on Precambrian basement and syn-rift sedimentary rocks. Structural control results in elongated fringing platform geometries aligned with fault scarps of normal faults. Fore-reef coral-algal rudstone facies are well preserved, whereas back-reef deposits are preserved only in some locations. Diagenetic alterations include marine cementation, meteoric dissolution, dolomitization, and localized Mississippi Valley-Type (MVT) mineralization with Zn, Pb, Cu sulfides, barite, and Mn oxides. These features reflect multiple diagenetic stages and variable fluid histories. The platforms exhibit consistent structural and sedimentological patterns along the margin, highlighting the influence of tectonic setting on carbonate development. The results support the application of these outcrops as analogues for subsurface systems in rift-related carbonate plays.