Abstract: Embodiments of the present invention provide a method and apparatus for geomodel uplayering. The method may include calculating one or more vertical cell property means for cells within a three-dimensional geomodel, generating at least one vertical mean trend sum utilizing the vertical cell property means, grouping cells utilizing at least one of the vertical mean trend sums to define a plurality of cell regions, calculating at least one horizontal cell property variance for at least one of the cell regions, and forming a plurality of cell blocks utilizing one or more of the horizontal cell property variances.

Abstract: Embodiments of the present invention provide a method and apparatus for geomodel uplayering. The method may include calculating one or more vertical cell property means for cells within a three-dimensional geomodel, generating at least one vertical mean trend sum utilizing the vertical cell property means, grouping cells utilizing at least one of the vertical mean trend sums to define a plurality of cell regions, calculating at least one horizontal cell property variance for at least one of the cell regions, and forming a plurality of cell blocks utilizing one or more of the horizontal cell property variances.

Abstract: A 3-D seismic prospecting method is provided which employs an areal array of sources and receivers by which seismic traces are generated. The areal array is segregated into a plurality of shells and angularly separted sections from which a preselected number n.sub.1 of source-receiver pairs are selected for a particular common midpoint. By means of the shells and sections, the source-receiver pairs so selected have associated therewith a wide range of offsets and azimuth angles for the preselected fold n.sub.1. The seismic traces corresponding to the selected source-receiver pairs are summed to give a stacked trace corresponding to the common midpoint.

Abstract: A method of processing seismic data enables correlation of P and S-wave seismic traces. First, P and S-waves are transmitted into the subsurface. The two-way vertical travel times are then measured for each wave to different depths so as to yield two sets of time-depths pairs. Mathematical functions relating two-way vertical travel time, T.sub.s or T.sub.p, and depth are fitted to each set of time-depth pairs. These functions are combined to yield an expression relating T.sub.s and T.sub.p. This expression may be utilized to rescale one of the traces to yield correlated P and S-wave traces.

Abstract: A method for enhancing the intensity of a photoacoustic signal by surrounding a solid with a gas having a normal boiling point at least about 25.degree. C. below the temperature at which the photoacoustic effect is being measured and a critical temperature not less than about 2.degree. C. By utilizing a second gas, selected from the permanent gases having a critical temperature not greater than about -73.degree. C., the surface area of a solid can be measured in accordance with procedures and relationships herein described.