Patent ID: 7796468

Claim:
A method for identifying shallow subsurface drilling hazards located below the earth's surface and including karsts, voids, unconsolidated discontinuities and partial collapses, said system utilizing petroleum exploration seismic survey data prepared for a specified portion of a geological formation containing existing wells, the method comprising the steps of: a. providing the original seismic data that includes reflection and refraction wave data collected for the specified portion of the geological formation; b. filtering the seismic data to remove or mute the reflection wave data; c. gathering and retaining the refraction wave data; d. filtering the seismic refraction wave data by filter means selected from the group consisting of time FK, KL, data driven, and combinations thereof; e. time-shifting and correcting the filtered data for linear move out (LMO); f. separating each refraction wave and computing statics selected from datum statics, elevation statics and combinations of both; g. computing residual statics for each refractor wave to provide refraction mini-volumes; h. binning and stacking the refraction mini-volumes obtained in step (g); i. loading the data from step (h) into a three-dimensional visualization computer program and operating the program to provide visual displays selected from 3-D X/Y/T space, inline and cross-line space and timeslice space; j. generating a semblance cube for each refraction wave mini-cube volume; k. flattening the time image of each of the refraction wave mini-volumes and semblance cubes and displaying the flattened images; l. displaying the time-slice domain visually; m. comparing the refraction wave mini-volumes and semblance cubes visual display from step (k) with historical experiential information derived from actual drilling operations of the existing wells in the geological formation; and n. based on the comparison of data and information in step (m), identifying the location, size and relative severity of any drilling hazards in the specified portion of the formation.