Patent ID: 7439977

Claim:
A method for displaying the three-dimensional vector orientations of magnetic fields on a two-dimensional surface comprising the following steps: a. establishing a sampling grid over an area of geological interest having magnetic fields; b. locating equally-spaced measuring stations for measuring said magnetic fields on said sampling grid, wherein said measuring stations are designated by letters; c. creating a two-dimensional map of the sampling grid; d. establishing a calibration station using a stationary tri-axial magnetometer for calibrating said magnetic fields, wherein said calibration station is located proximate to said sampling grid, and further wherein the calibration station is located in a magnetically quiet area; e. conducting a calibration step at the calibration station, wherein said calibration step comprises the steps of: i. obtaining a first measurement of the magnetic field in X, Y and Z directions using said stationary tri-axial magnetometer; ii. obtaining a second measurement of the magnetic field in X, Y and Z directions using an operator held portable tri-axial magnetometer; iii. determining the effect of said operator holding the portable tri-axial magnetometer on said second measurement; and iv. calibrating said effect to the portable tri-axial magnetometer so that the effect of the operator is nullified; f. conducting a survey step of obtaining magnetic field measurements at each of said measuring stations using said portable tri-axial magnetometer and recording the time at which said magnetic field measurements were taken, wherein the magnetic field measurements are represented in three dimensions as Cartesian coordinates X a , Y a and Z a where “a” indicates the measuring station designation, and wherein said survey step occurs over a period of time; g. measuring the magnetic field at the calibration station over said period of time and determining an average magnetic field measurement over the period of time in order to obtain a calibration value corresponding to the time that the magnetic field measurements are made; h. correcting the magnetic field measurements by subtracting said calibration value in order to obtain a calibrated value for each of the magnetic field measurements X calibrated , Y calibrated and Z calibrated ; i. correcting said calibrated value for each of the magnetic field measurements by subtracting the value of the magnetic field of the earth at each measuring station to obtain a residual value for each magnetic field measurement X residual , Y residual and Z residual , wherein said value of the magnetic field of the earth is determined by applying the International Geomagnetic Reference Field; and j. correcting said residual value by subtracting the values of induced magnetic fields to obtain a remanent value for each magnetic field measurement X remanent , Y remanent and Z remanent .