GEOPHYSICAL SURVEY METHOD Russian patent published in 2013 - IPC G01V11/00 

FIELD: physics.

SUBSTANCE: disclosed is a geophysical survey method for media with an acoustic hard layer in the overburden of a geologic profile. The method involves detection of seismic waves refracted on or reflected from the cover of the hard layer. In addition to seismic survey, the disclosed method involves detection of the gravitational field along seismic profiles. Gravitational anomalies are detected within this field and the position of vertical contacts lying within the hard layer are mapped based on the gravitational anomalies. Correlation relationships between seismic velocities and densities are used to determine density of sections of the hard layer separated by contacts and the capacity of the sections of the hard layer, from which the position of the bottom of the hard layer is determined, is determined by solving the inverse gravimetrical problem. The value of seismic velocity, determined in the hard layer using known seismic survey methods, as well as the capacity of the layer determined using the disclosed method based on gravitational data, is entered into a seismic model used to image the medium by migration of seismic waves reflected from boundaries lying under the hard layer.

EFFECT: high reliability investigating deep reflecting seismic boundaries by taking into account the effect of high-speed non-uniformities of the top part of the section.

2 cl, 3 dwg