Biozonation and Paleoenvironmental Evaluation of Sapele Fields, Niger Delta, Southern Nigeria
Keywords:
Palaeoenvironmental, Biostratigraphic data, Depositional, Biozonation, WirelinesAbstract
Palaeoenvironmental and Biozonation analysis was carried out on Sapele fields (Sapele Deep and Sapele Shallow) using the biostratigraphic data, twelve digital wirelines well-log data, and the international stratigraphic guide. Five depositional environments were delineated based on the biofacies information interpreted from the qualitative and quantitative evaluation of the benthonic foraminifers’ assemblages. The depositional environments of the study area are Bathyal Depositional Environment, Outer Neritic Depositional Environment, Middle Neritic Depositional Environment, Inner Neritic Depositional Environment and Littoral Depositional Environment. Six biozones were deciphered from the field of study and they include, Catapsydrax dissimilis Concurrent-range zone, Praeorbulina glomerosa interval zone, Globoturborotalita nepenthes Concurrent-range zone, Globorotalia margaritae partial-range zone, Dentoglobigerina altispira interval zone and Globigerinoides fistulosus interval zone. According to the qualitative and quantitative analysis of biofacies data, the study area's interpreted depositional environment fluctuated between shallow marine and deep marine (inner neritic to middle neritic to outer neritic to bathyal depositional environment) for Sapele deep and between marginal marine and deep marine (littoral to inner neritic to middle neritic to outer neritic depositional environment) for Sapele shallow.