METHOD OF IDENTIFYING SUBSURFACE STRUCTURES AND LOCAL OBJECTS DISPOSED IN THESE STRUCTURES Russian patent published in 2005 - IPC

FIELD: identification of subsurface structures.

SUBSTANCE: according to the method, parts of damaged lithological layers are identified from minimal instant values of amplitude of autocorrelation and mutual correlation functions of results of sampling at the condition that amplitude tends to zero. Water-saturated lithological layers are selected by analyzing two groups of phase spectrum of long-wave and short-wave ranges taking into account that phase difference for two groups of data equals to zero. Local objects in subsurface layers are found from the condition that phase difference of instant values of auto- and mutual correlation of long-wave and short-wave range signals reflected from extended lithological layers doesn't equal to zero if power exceeds maximal received wavelength. The other condition is that structure of auto- and mutual correlation functions, i.e. phase, amplitude and signal period of longwave and shortwave ranges totally coincides or with magnification of one of ranges. Local object is registered by means of shortwave spectrum of reflected signal. Reflected waves difference in intensity in shortwave and longwave spectral ranges within cut limits where local object is present. Changes in amplitude and phase of instant values of auto- and mutual correlation functions of longwave spectrum has strongly expressed trend to growing or reducing. Changes in amplitude and phase of instant values of auto- and mutual correlation functions of signal of short-wave spectrum have oscillation character. Geometric average size of local object is found fro interval within limits of which interval there is the difference between changes in amplitude and phase of instant values of auto- and mutual correlation functions of long-wave and short-wave spectra.

EFFECT: improved reliability of identification.

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