Biostratigraphy And Paleoenvironment Of The Coniacian Awgu Formation In Nzam-1 Well Anambra Basin Southeastern Nigeria.

ABSTRACT - Ditch cutting samples from an exploratory Nzam-1 well located in the northwestern part of Anambra Basin were subjected to lithological description and palynomorph enrichment and analysis through digestion with Hydrofluoric acid HF and floatation with Zinc Bromide Zn2Br4. The study was intended to determine the relative geologic age and paleoenvironment of deposition of Awgu Formation through the application of palynologic tool. The lithostratigraphy of Awgu Shale is mainly shaley in nature and diagenized at different degrees within various stratigraphic levels. Palynological study revealed that the sequence is dominated by angiosperm pollen such as Monocolpites sp Tricolpites sp and Retimonocolpites sp. Other diagnostic forms that characterize the formation include Zlivisporites blanensis Peromonolites perireticulatus and Odontochitina sp. Thus the Awgu Shale is dated Coniacian age. However new forms of dinoflagellates appeared in the sediments that are suggestive of transitional environment of deposition.