The value of building a multiscale, regional geomodel for reserves assessment of the Midland Basin

Modern resource assessment approaches can be greatly aided by incorporating all available data and interpretations in a three dimensional geomodel. Our goal is to offer a regional perspective to augment the interpretations from local, field-scale 3D models developed by the industry. In this work we highlight the benefits of continuous development of the geomodel for reserves assessment in an unconventional play. We generated a three dimensional, faulted Midland Basin geomodel, containing over 1 billion cells, including stratigraphic, petrophysical, core description, and production data for the Spraberry and Wolfcamp intervals. The model is based on over 1500 correlated wells, 700 wells with petrophysical and facies interpretations and approximately 6000 horizontal production wells with decline curve and completion data analyses. There are three areas of focus: 1) Testing of the facies model derived from log and core analyses using different deterministic and stochastic attribute distribution techniques; 2) Characterizing the relationship between data density requirements and model predictability; and 3) Exploring the influence of geological trends on productivity. This work demonstrates the value of a multiscale, regional perspective to the practice of 3D reserves assessment in the Midland Basin.