METHOD OF, AND APPARATUS FOR, FULL WAVEFORM INVERSION

摘要

Method of, and Apparatus for, Full Waveform Inversion There is provided a method of subsurface exploration, the method comprising generating a geophysical representation of a portion of the volume of the Earth from a seismic measurement of at least one physical parameter. The method comprises the steps of: a) providing an observed seismic data set comprising at least three distinct non-zero data values derived from at least three distinct non-zero seismic measured values of said portion of the volume of the Earth; b)generating, using a subsurface model of a portion of the Earth comprising a plurality of model coefficients, a predicted seismic data set comprising at least three distinct non-zero data values;c)generating at least one non-trivial convolutional filter, the or each filter comprising three or more non-zero filter coefficients;d)generating a convolved observed data set by convolving the or each convolutional filter with said observed seismic data set; e)generating one or more primary objective functions operable to measure the similarity and/or mismatch between said convolved observed dataset and said predicted dataset;f)maximising and/or minimising at least one of said primary objective functions by modifying at least one filter coefficient of the or each convolutional filter;g)generating one or more pre-determined reference filters comprising at least three reference coefficients;h) generating one or more secondary objective functions operable to measure the similarity and/or mismatch between the filter coefficients for the or each non-trivial filter and the reference coefficients for the or each pre-determined reference filters; andi)minimising and/or maximising at least one of said secondary objective functions by modifying at least one model coefficient of said subsurface model of a portion of the Earth to produce an updated subsurface model of a portion of the Earth; and j) providing an updated subsurface model of a portion of the Earth for subsurface exploration.