Method and apparatus for simultaneously collecting spatially and temporally varying magnetic survey data
US5444374A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 1993 |
| Grant date | Aug 22, 1995 |
| Priority date | — |
| Expiry date | Feb 5, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and a device for implementing the method, for geophysical surveying of an area (1) including continuous measurement of the earth's magnetic and electromagnetic field using a detector (6) held at a constant height (E) above the ground surface, in the order of one meter, while traversing in a criss-cross manner over the area (1) at speeds below a maximum speed (S), in the order of 10 km/h, and utilizing measured signal frequencies below a cutoff (F), being approximately the maximum speed (S) divided by twice the detector height (E), to indicate spatial variations in the measured field. Traversal distance can be measured on board the host vehicle and a real time output supplied. Simultaneously, using the same detector (6) and artificially induced magnetic fields generated by an inductive (2b and/or galvanic source (2a)), temporally varying fields having frequencies above the cutoff (F) can be measured and simply filtered out of the detector's (6) output for separate processing and storage. Temporally varying fields below the cutoff (F) can be detected by a synchronized stationary detector inputting to the processing equipment (10) so as to subtract such signals from the signa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.