Applications of Dipmeter and Borehole Image Data in Static Models

Abstract

Recent advances in three-dimensional (3-D) static modeling functionality allow the full integration of dipmeter and borehole image (BHI) log interpretations. This chapter provides a summary of key applications of dipmeter and BHI log data in 3-D static models. These are discussed sequentially as they occur in the reservoir modeling workflow. The key strength of dipmeter- and BHI-constrained reservoir models is the incorporation of directional information at the wellbore that can represent subseismic properties and provide local calibration for seismic derived attributes. Dipmeter and BHI log integration starts with data import. Using corporate nomenclature and predefined templates ensures consistency between projects and interpreters. Data visualization with dipmeter and BHI data can be used to derive conceptual structural and depositional models. Display of tadpoles and false-color images are an important component for facies subdivision and stratigraphic correlation to define flow units in the reservoir model. Facies dimensions and paleocurrent analysis based on dip trend analysis also influence the choice of modeling grid cell size and direction. The orientation of facies belts can be steered by paleocurrent maps that add detail and calibration to trends seen in seismic volumes and dynamic properties. Matrix property modeling is more accurate if net-to-gross definition is based on core-calibrated sand counts from BHI logs. During structural modeling, dip and azimuth data can be used to constrain structure maps in areas with poor-quality seismic data. Fracture modeling is a unique application of BHI logs, the only data that provide quantitative fracture properties down to the millimeter scale. The knowledge of local and regional stress distribution is primarily based on dipmeter and BHI analysis and is an essential input for 3-D fracture modeling, well planning, and other applications.