Predicting Frac Performance and Active Producing Volumes Using Microseismic Data

Summary We present an approach for managing unconventional reservoirs that uses passive seismic recordings captured on time intervals of months similar to 4D surface reflection surveys. Computing the producing volume at regular intervals over the years of production allows for better decisions on the design of the frac treatments for future wells and for the determination of where to do infill drilling. The installation of a shallow buried grid over the reservoir provides for efficient recording of the data at the times required for monitoring frac treatments and for computing the producing volumes. Using fracture imaging, the fracture systems in the reservoir are computed before the frac treatment, during frac treatment, and during production. A byproduct of the fracture imaging method is the ability to store the first time of activation for each segment of each fracture. This allows for detailed analysis of how the rocks are fracturing. In addition to monitoring unconventional reservoirs the method is being used for monitoring CO2 injection. It has been used for reservoir fluid flow monitoring and can be used for monitoring cuttings disposal wells to track the movement of fluids.