A new method is presented to compile all the available data from wireline logging or logging-while-drilling in a format suitable for direct input in 3-D hydraulic fracture models. Because of the differences in format and data density, log data are not always used optimally in 3-D hydraulic fracture modeling. They do provide however the most comprehensive and continuous parameters for borehole stress profile, permeability index, elastic moduli, lithology, porosity and fluid saturations. An automatic zoning technique divides the data into consistent intervals based on stress contrast. The representative design parameters are then computed for each zone. The outputs are a blocked stress profile and zoned fracture design parameters.
The availability of a stress profile based on rock mechanical analysis from wireline logs, microfrac tests and core data specifically designed for use in 3D hydraulic fracture simulators has stimulated the use of these data in the selection of candidates for stimulation treatment. Post-frac radioactive tracer logging has shown that the automatic zone selection identifies natural barriers to hydraulic fracture extension. This new product provides a synergistic approach to hydraulic fracturing in which wireline logs and rock mechanical analysis are fully utilized together with microfrac tests, core data and production history to optimize the execution and economics of the field development process.
Improved candidate selection (wells and reservoirs) for stimulation treatment in a South Texas gas field increases production while reducing the number of fracture treatments and total stimulation cost. Pre- and post fracturing logs are compared to show adequate stress profile compilation.