Patent ID: 6775620
Filing Date: 2004-08-10
Classification: G01V

Abstract:
A method of locating a surface in a three dimensional volume of data indicative of surface characteristics, comprising:a. transmitting an acoustic signal into the earth; b. receiving a multiplicity of reflected acoustic signals from the earth, resulting from the prior transmitting step with a receiver array comprising at least three non-colinear receivers which define a grid of trace locations having an x axis dimension and a y axis dimension perpendicular to the x axis dimension to further define a set of trace locations, {xi, yi}; c. recording the amplitude of each reflected acoustic signal as a function of time to construct a seismic volume comprising a seismic trace for each recorded acoustic signal and wherein the seismic volume comprises a time axis dimension, t, that measures the time of each reflected acoustic signal, wherein the t axis dimension is perpendicular to the x axis and y axis dimensions; d. selecting an amplitude characteristic of interest for the seismic volume; e. for at least three distinct (x, y) grid locations in the seismic volume, locating the selected amplitude characteristic of interest in time to produce a set of picked points, {xj, yj, tj}, where {xj, yj} is a subset of {xi, yi}; f. for at least one trace location (xi, yi) in the volume, determining a set of grid coordinates {xi, yi, ti} by calculating a time value ti based upon the set {xj, yj, tj} and the location (xi, yi); g. storing the set of coordinates {xi, yi, ti} determined in step (f); h. selecting a grid location (xi, yi) in a first autopicking direction; i. determining the value of ti at the selected grid location from the data stored in step (g); j. locating an amplitude characteristic of interest at the grid location that is within a preselected distance of the value of ti determined in step (i); k. determining whether the amplitude characteristic of interest located in step (j) meets a predetermined selection criterion of the value of ti determined in step (i); and l. storing the location of each amplitude characteristic of interest that meets a predetermined selection criterion of the value of ti determined in step (i).