Abstract
In a major advance over previous capabilities for prefracturing design and real-time field application of hydraulic fracturing models, the ability to accurately handle complex pumping schedules and reservoir conditions has been achieved by developing the capabilities for full three-dimensional hydraulic fracture analysis and combining these with the speed of lumped model simulations. These lumped (spatially integrated) models have already been used for the design and realtime analysis of numerous fracture treatments. Now, a fully 3-D code, based on finite elements and surface integrals, developed as part of a comprehensive field monitoring and analysis project for the Gas Research Institute, is being used to analyze fracture geometries and pressure distributions for many variations of viscosity scheduling and stress barrier placement. Analysis of these 3-D results produces integration coefficients which can be implemented in the lumped models. These coefficients enable the lumped model to accurately account for viscosity and pressure variations in the fracture, and for differences in confining stress magnitude in the strata above and below the payzone. This work allows the lumped models to be made more quantitatively correct by incorporating the essence of full 3-D modelling capabilities without any loss of execution speed. The effectiveness of the methodology is demonstrated by performing simulations with a number of data sets from field operations as input.
