Abstract

Ditch cutting samples recovered from interval 640 to 3500 ft of Deb-1 well in the Niger Delta Basin, Nigeria were investigated for sedimentological and palynological characteristics. The stratigraphic successions in the well include shale, shaly sand, sandy shale and sand. Palynological zonation of the studied interval of the well is largely based on palynofloral assemblage of significant species recorded as well as their stratigraphic distribution with respect to a reference zonation scheme. The result of the section of the well analyzed has been broadly assigned to the P520, P480 and P470 palynological zones. The upper boundary of P520 was tentatively placed at 640 ft, the depth of the first sample analyzed while its zonal base is marked by base occurrence of Racemonocolpiteshians at 1,120ft. P520 zone is characterized by the presence of Racemonocolpiteshians Peregrinipollensnigericus, Ctenolophoniditescostsatus, Verrutricolporitessp, Echiperiporitesestalae, Brevicolporitesguinetii Verrucatosporitesusmensis and Nymphaeaepollisclarus. The top of P480 is defined by base occurrence of Racemonocolpiteshians at 1,120 ft while the base is marked by the base occurrence of Cinctiperiporitesmulleriat 2,130ft. P480 zone is mainly characterized by maximum development of Spinizonocolpitesmacrobaculatus, Spinizonocolpitesechinatus and Spinizonocolpitesbaculatus. The top of P470 is defined by base occurrence of Cinctiperiporitesmulleri at 2,130 ft while the base is tentatively placed at 3,525 ft. The assemblage of palynomorphs recovered from the well indicates coastal to marginal marine environment of deposition. The studied interval has been assigned Late Eocene to Early Oligocene age based on the evidence from palynological studies.