Abstract
The concept of Augmented Depletion Development (ADD) was introduced to the industry through a pilot project conducted in the Bakken play in the United States (US). These wells are open-hole wells drilled within the fractured network of a pad. They are not fractured stimulated deliberately but do produce and contribute to the overall production of the lease. In this study, we use numerical modeling to understand the potential performance of these wells in several plays across the US.
The study is based on results obtained from the simulations run on a numerical model that combines hydraulic fracturing, geomechanics, and reservoir flow in one code. This allows for a better understanding of the influence of different parameters on the performance of these wells and their potential influence on the well-performance. This study assesses ADD's potential in 4 US plays: Bakken, Eagle Ford, Midland, and the Anadarko Basin. The sensitivity was conducted based on the time of stimulation of the child well and the time of drilling the ADD well. The spacing of the existing wells is the one that existed before drilling of the ADD well. Incremental production from each of the scenarios was compared. An uncertainty analysis on proppant degradation was conducted to assess the effect of proppant degradation on the production decline.
Results showed that ADD wells’ performance varies from one play to another. The trend shows that these wells tend to perform better as the permeability improves. The incremental production is in the range of 5%-20% and was shown to be directly proportional to the well spacing. These wells produce lower volumes when drilled later in the field development phase as the pressure in the reservoir drops. In tighter spacings, these wells compete for the same volume as the stimulated wells. The proppant pack degradation with time results in reduced production, though the incremental production remains unchanged. Although these wells are not economically viable in all cases, their implementation does require wider well-spacing. For the best results such wells must be introduced at the onset of drilling program and should be made ready to produce at an early stage of field development.
This work is the first published simulation that attempts at assessing a new technology for various plays across the United States. The learnings from this study can be used as a benchmark for operators that are planning on implementing such wells in their field development programs.