Exploration system for enhancing the likelihood of predicting lithology of earth formations associated with deposits of ore, marker rock and/or economic minerals

Claim 1

Method of accurately determining lithology of an earth formation to identify ore, marker rocks, economic minerals or the like, using a refraction exploration field system including a series of detectors, positioned along a line or survey at inline positions X 1 , X 2 , . . . X n and at least one seismic source located adjacent to said detectors for producing a seismic wave for travel through said formation: (a) generating a seismic wave at a first sourcepoint location adjacent said series of detectors; (b) after said wave undergoes refraction, detecting arrival of a refracted wave at said series of detectors at said inline offset positions, to obtain a first set of traces associated with said offset positions X 1 , X 2 , . . . X n ; (c) repeating steps (a) and (b) by generating a second wave at a second sourcepoint adjacent to inline position X n of said detector positions, and detecting said refracted wave to obtain a second set of traces; (d) advancing said series of detectors a selected number of inline positions or fractions thereof and repeating steps (a), (b) and (c) above to obtain additional sets of traces, but in which said additional sets of traces are associated with more than two inline positions overlapping common inline positions of said first and second sets of traces; (e) distinguishing arrival times of shear waves from compressional waves so as to indicate true compressional and shear wave velocities associated with a series of depth intervals within said earth formation; (f) after computing compressional and shear wave velocity values for a plurality of mineral compositions of variable size, comparing such computed values with said indicated true compressional and shear wave velocities of step (e) whereby the lithology of said earth formation can be accurately predicted.