Unconventional oil and gas reservoirs present challenging problems for reservoir engineers tasked with predicting the future performance of undrilled and recently completed wells. In conventional reservoirs, there are many analytical techniques that can be used, but unconventional reservoirs present too many complexities, variations and unknowns to apply these methods. In particular, the extent, geometry and conductivity of the fracture network are unknown, and perhaps impossible to model.
A common solution used by many engineers is to use production data from existing wells nearby as analogues for future wells to generate a type well profile (TWP), also known as a type curve. These type curves are an important bit of information that appears often in company presentations.
They are derived by selecting analogous wells, collecting their production history and key well information, and applying several mathematical adjustments to generate the prediction.