32E04SE0035 - Geology Ontario

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6.0 MAGNETOMETER SURVEY
The old baseline was extended from 30E to 54E with stations
established at 25 metre intervals. Crosslines were established at
200 metre intervals from 36E to 54E (eg. 36E, 38B, 40E, 42E, 44E,
46E, 48E, 50E, 52E and 54E). A proton total field magnetometer
survey was carried out over this grid.
A Geometric G-816
proton total field magnetometer with direct
readout was used for the survey. Magnetic diurnal variations
were monitored by establishing base stations at 25 metre
intervals along the baseline. Readings were taken along grid
lines spaced at 200 metre intervals with stations spaced at 12.5
metres along the line. Magnetic diurnal variations were monitored
by looping lines and checking into established baseline base
stations (at the intersection of baseline and crosslines) at
intervals of less than one and one half hours. Approximately 12.6
line kilometers of data were recorded in this way.
Corrections to the magnetic field values recorded during the
field
survey were made using the approximate time and diurnal
change information. A regional value of 58,000 gammas was
subtracted from all the corrected magnetic values. The values
were then plotted at a scale of 1:5000 and profiled along the
line using a base of 58,400 gammas. A separate magnetic value and
profile map was produced and then reduced to a scale of 1:10,000