High-resolution Danian–Selandian benthic foraminifera-based paleoenvironmental reconstruction and response to sequence stratigraphy: Inferences from the Elles section, El Kef Basin, Tunisia

Abstract

High-resolution (123 samples) benthic foraminiferal distribution patterns were analyzed for paleoenvironmental reconstruction from a section located at the southern edge of the El Kef Basin (El Haria Formation; Tunisia) spanning the Danian–Selandian interval (planktic foraminifera P1a–P4b zones). Five distinct clusters were identified, each representing different paleoenvironments and depths ranging from inner neritic to upper bathyal, with significant variations in species diversity, paleoproductivity, and bottom water oxygenation. The Dan-C2 hypothermal event is characterized by moderately oxygenated bottom waters, high species diversity, and lowered paleoproductivity within an upper bathyal setting. The LDE is marked by high species diversity, higher paleoproductivity, moderately oxygenated bottom waters, abundance of epifaunal species, and shallowing to middle neritic depths. The Danian-Selandian boundary records (a) a sudden abundance of the inner neritic infaunal species Bulimina strobila, (b) an increase in species diversity, (c) moderately‑oxygenated bottom waters, (d) a positive δ¹³C excursion, and (e) deepening, from inner to middle neritic settings. Four transgressive-regressive (T-R) cycles based on benthic foraminiferal assemblage-derived bathymetry, P% and the transfer function-based estimate mirror each other, and distinctly mirror paleodepth changes, correlating with global eustatic cycles but also reflecting local tectonic influences.