Overpressure zone Detection/Pore pressure prediction in an offshore Niger Delta field using Drilling and Petrophysics parameters

It has been evaluated that over pressured matrix formations are identified with deep water Niger Delta basins given a normal average pressure gradient of 0.64psi/ft. Conventionally, a pressure gradient greater than this is known to be taken as an abnormal over pressured zone. This will then serve as a resource description in a log enhanced data/ information of a subsurface as a hydrocarbon prospective prediction / prediction evaluation.

In this study, the plot of depth against pore pressure from the depth of 2460 m at which parameters were taken were recorded to the depth of 3674m. Therefore, it should be observed that the pore pressure increased following a normal trend until it reaches a depth of 2975m where the deviation from the usual trends till it reaches a depth of 2975m where the deviation commenced, this trend therefore continues gradually till it reaches 3670m where a significant increase of pore pressure from 9.8ppg to 12.9ppg at 3674m was observed.