Authors : Christopher Uyabeme Enuenwosu; Walter Memirhuraye Umuze

Volume/Issue : Volume 11 - 2026, Issue 6 - June

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DOI : https://doi.org/10.38124/ijisrt/26jun284

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Abstract : Detailed sedimentological studies of the Ilaro Formation from the Ajegunle, Papalanto, and Ifo outcrops in the eastern Dahomey Basin, southwestern Nigeria, were undertaken to interpret depositional processes and paleoflow patterns. The formation comprises medium- to coarse-grained cross-bedded sandstones with clay drapes, reactivation surfaces, and rare mudstone interbeds. Measured paleocurrent azimuths from cross-bed foresets indicate a dominant NE–SW paleoflow direction, implying sediment derivation from the inland Precambrian basement complex towards the Atlantic margin. Vertical facies successions show upward-fining cycles, typical of meandering fluvial channels that evolved into tidally influenced environments near the paleo-shoreline. The combined evidence supports deposition in a mixed fluvial–tidal system, consistent with the Paleogene paleogeography of the Dahomey Basin.

Keywords : Ilaro Formation, Sedimentary structures, Paleocurrent analysis, Dahomey Basin, Fluvial–tidal transition, Paleogene Nigeria.

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