Method for determining geometric caracteristics of a hydraulic fracture

摘要

Method for determining geometric characteristics of a hydraulic fracture comprises performing a baseline seismic survey for a geological formation including excitation of first seismic signals and registration of first reflected and refracted seismic signals. A velocity model is created by combining results of the baseline seismic survey and an additional geoscientific information, and seismic properties of the geologic formation are evaluated. At least one strong flat lithological reflector disposed below a planned fracture is identified. A numerical model of elastic wave propagation in the geologic formation with a fracture with given properties is created. Hydraulic fracturing is performed and after fracturing when the fracture is maintained open and pressurized seismic surveys are performed, including excitation of second seismic signals and registration of second reflected and refracted seismic signals. The fracture's dimensions and shape are determined by comparing the first and the second reflected and refracted seismic signals and solving an inverse problem with the use of the numerical model.