PALEOENVIRONMENTAL RECONSTRUCTION OF THE EASTERN MARGIN OF THE IVORIAN OFFSHORE SEDIMENTARY BASIN USING SEDIMENTOLOGICAL AND MICROPALEONTOLOGICAL ANALYSES OF BENTHIC MICROFAUNAL ASSEMBLAGES FROM THE J1 WELL.

Drill cuttings from the J1 well, corresponding to the 2160-2480 m interval and located on the eastern margin of the Ivorian offshore sedimentary basin, were subjected to integrated lithostratigraphic, biostratigraphic, and micropaleontological analyses. Sixteen samples were processed following a protocol that included washing, sieving, and examination under a binocular microscope. The results reveal a lithology dominated by black clays (70%), associated with fine-grained sandstones (25%) and limestones (5%), with intercalations of pyrite and carbonaceous debris. The microfauna is mainly composed of agglutinated benthic foraminifera, representing 77% of all identified foraminifera, grouped into 12 genera and 18 species. Biostratigraphic analysis allowed the identification of four intervals assigned to the Cenomanian (2480-2390 m), Turonian (2390-2245 m), Santonian (2235-2205 m), and Campanian (2205-2160 m). The combined sedimentological and micropaleontological data suggest a relatively deep marine environment ranging from the outer shelf to the upper bathyal zone, characterized by reducing conditions favorable to the preservation of organic matter.