Borehole image structural modelling and synthetic dip modelling in 3D

Abstract

Summary Borehole images are studied with open hole log, core and regional knowledge to refine models. This is upscaled, to delineate reservoir geometry and to optimise well placement for reservoir development and production optimisation. We developed software-based workflows to improve the efficiency of structural well zonation by simultaneously working with depth based structural plots together with enhanced vector and stereo plots which can be directly edited into reports with minimal editing. These structural zones are then further subdivided into structural elements (fault drag, fold limbs etc.). These structural elements are a discriminated Structural Dip set, that effectively upscales the detailed Manual Dip Set, to a Structural Dip Set. A geometric model is then selected in our Structural Interpretation Advisor which extends a model from the well path, by Bezier surfaces. A Synthetic Dipset is then generated from the layer surface intersections with the well path and overlaid on the Structural Dip Set. The synthetic and Structural dips is iterated to achieve a better fit of synthetics to dips, by manipulating the model in the X, Y and Z, tilt, plunge, throw etc. This approach adds confidence in conventional dip interpretation by allowing 2D, 3D and map visualization of complex structure.