Successful hydraulic fracture treatments require sound frac designs based on reservoir geomechanics and geology. This paper demonstrates a workflow that integrates Discrete Fracture Network (DFN) simulation with Tomographic Fracture Imaging & trade; (TFI), a passive seismic monitoring method (Geiser et al., 2012; Lacazette et al., 2013). DFN models are built at the level of detail of individual fractures using information resolved using the TFI approach. These DFN models are then used to understand reservoir production and geomechanics.
This paper shows examples of DFN simulations that predict frac propagation and reactivation of natural fractures by hydro-shearing and hydro-jacking. By tracking fracture propagation and reactivation, the simulator produced hydraulic fracture fields that can be compared to and calibrated with observed TFIs. This process provides confidence in both the Stimulated Reservoir Volume (SRV) and Tributary Drainage Volume (TDV) determined for the fracture treatment. The distinction between SRV and TDV is important, because induced hydraulic fractures and natural fracture reactivation can produce seismic activity in a larger volume than actually contributes production. Also, natural fractures can contribute production from regions outside the SRV if hydraulic fractures effectively connect the well to the natural fracture network. The calibrated simulations of TDVs provide a basis for improved frac designs, well-test analyses and production forecasts.