Quantifying a reservoir volume and pump pressure limit

Abstract

Methods for computer modelling of a pressure transient behavior after shut-in and during fall-off of an injection event are provided to provide estimates of stimulated reservoir volume, formation permeability, stress contrast across the target and adjacent zones, fracture dimensions, fracture beyond the target zone, and pump pressure limits for maintaining fractures within the target zone, especially in fractured tight reservoirs.

It is claimed: 
     
         1 . A method for computer modelling of a pressure transient behavior after shut-in and during fall-off of an injection event, the method comprising:
 inputting field data, including at least the pressure and time data, after shut-in and during fall-off of an injection event;   pre-treating the input data;   creating curve plots using the Input Data, including derivative curves;   isolating the water hammer effect from the pre-treated data;   selecting initial estimates for type-curve parameters for the upper and lower limit curves;   checking to ensure that input field data fits within the upper and lower limit curves;   simulating type-curves by modifying the curve parameters using a curve-fitting, convergence algorithm;   calculating a stimulated reservoir volume;   calculating stress contrast solutions including the stress contrast is the difference in stress between the target injection zone and adjacent containment zones;   conducting iterative fracture simulations to calculate a maximum injection pressure at which containment stresses are not exceeded; and   providing an injection pressure limit to assure containment in the targeted fracture zone.