Tectono-eustasy and basin morphology controls on Cretaceous facies architecture in the northeastern margin of Arabian Plate

Abstract

Basement highs and adjacent basins are significant structural elements controlling regional facies architecture. Overprinted by fluctuating sea-levels, the correlation of facies units from the crest into the flank environments is often challenging. Here, a case example of an upper Turonian–lower Campanian palaeohigh on the northeastern margin of the Arabian Plate is presented. Two stratigraphic sections (Jarhum and Qazi, respectively) compare the depositional dichotomy between crest and flank. The palaeohigh Jahrum section documents a deepening upward succession that includes brackish carbonates at the base, followed by shallow–marine carbonates, and culminates in basinal deposits. The sedimentary record of Santonian deposits in the Qazi section (flank) comprises stratigraphically thick calciturbidites, calcidebrites, slump folding, clinoforms, and channel-fill deposits, which conformably overlie deep-water deposits. This case study provides insights into processes that are rarely documented in the Tethyan realm. Data shown here exemplify the interaction between regional uplift (related to tectonic inversion) and eustatic sea–level changes. The regional correlation of the facies architecture highlights important lateral variations in facies and stratigraphic thickness controlled by bathymetry and seafloor inclination related to the geometry of the palaeohigh. We suggest that the redeposited carbonates described here are characteristic of tectonically active intervals along slope settings. Furthermore, we demonstrate that sustained carbonate production on unrimmed, distally steepened ramps supports the deposition of calciclastics. The data presented are crucial for understanding redeposition processes in Cretaceous carbonate systems along the Arabian margin and beyond. © 2025 The Author(s)