Electromagnetic surveying
US7565245B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 2007 |
| Grant date | Jul 21, 2009 |
| Priority date | — |
| Expiry date | Sep 20, 2027 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B41/0099
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of analysing results from an electromagnetic survey of an area that is thought or known to contain a subterranean resistive or conductive body within a background strata configuration is described. The method comprises providing a set of electromagnetic field data obtained using at least one electromagnetic receiver and at least one electromagnetic source for a range of source-receiver separations, e.g. providing conventional controlled-source electromagnetic survey data. A subset of the electromagnetic field data is identified that comprises data obtained for source-receiver separations greater than a selected threshold offset. The threshold offset is chosen so that data beyond this offset are characteristic of magnetotelluric data. Thus the subset of data is then processed in accordance with a first technique to obtain information on the background strata configuration. Other electromagnetic field data obtained for source-receiver separations less than the threshold offset may then be processed in accordance with a second technique to obtain information on any subterranean resistive or conductive body within the background strata configuration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.