For the determination of the depth of a zone of hydraulic fractures in the earth

摘要

The depth of a zone of hydraulic fractures which is determined by the detection and the recording seismic movements undulatory in a series of points spaced apart from each other in depth in a part of a drilled hole 10 is subjected to the pressure of the fracture during a period of closure after the application of pressure while the zone of the fracture is unstable, and by the analysis of the recordings of movements, making it possible to separate and to eliminate the components that are attributable to the fracture of the discrete components of the seismic source attributable to the fracture in order to determine a mean level of the base of the vertical and horizontal components and to compare the mean level of the base of the horizontal components of the movement to the vertical component of the movement in order to obtain an indication on the presence or absence of fracture at each of the depth considered.