Integrated Workflow for Prediction of Drilling Hazards Due to High Pore Pressures in North Kuwait Fields

Understanding and mapping the subsurface pressure regime in order to identify drilling hazards is a crucial issue for oil and gas industry; a severe incident can lead to huge economic loss, and may put the operating personal in danger. The objective of this paper is to propose a methodology for pore pressure prediction in a Jurassic evaporitic formation, in Kuwait, and its associated risk, based on an integrated approach that includes three disciplines, Basin Modeling, Geophysics and Geomechanics.

Their integration led to a robust estimation of the pore pressure over the formation. Geomechanics, through Finite Element models, associated with Basin Modeling, allow understanding the genesis and evolution of over-pressure through time. Plus, Geomechanical models allow deriving an analytic estimation of pore pressure, while geophysics gives access to relevant mechanical parameters, through dedicated post-processing of elastic parameters from pre-stack inversion and lithology prediction.

While analyzing the data from an occured blow out, in addition to a robust pore pressure prediction within the formation, seismic reservoir characterization and seismic fracture characterization lead to the conclusion that drilling risk is expected to be even higher in limestone rich zones and close to sub-seismic discontinuities.