Scoring completion effectiveness in unconventional horizontal wells using 3D seismic attributes

Abstract

Using a multihorizontal well-completion pilot in an unconventional oil field in the Lower 48 (contiguous United States) Midcontinent, a workflow is proposed to evaluate the effectiveness of horizontal-well completions through 3D surface-seismic attributes and microseismic data. Three-dimensional surface seismic is often continuous over unconventional fields and provides a measurement in areas where no other data are available. In addition, microseismic is the only geophysical data that allows us to “see” the apparent hydraulic-fracture zone around a wellbore. Using these two geophysical tools integrated with engineering and geologic data such as image logs, total proppant, number of stages, estimates of fracture length and height, permeability, chemical tracers, and production rates, a “geophysical completion scorecard” is developed to evaluate a multiwell horizontal pilot and apply it to additional wells drilled outside the pilot in an effort to predict their completion effectiveness. A postdrill review of production rates in those wells shows good correlation to the scorecard's predictions of completion effectiveness.