Method of geophysical prospection using transient currents
US4417210A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1980 |
| Grant date | Nov 22, 1983 |
| Priority date | — |
| Expiry date | Jul 8, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/38
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a method of geophysical prospection a transmitter dipole and a receiver dipole which is sensitive to an electromagnetic field are positioned in cooperation with the subsoil. An impulsive excitation current is applied repeatedly to the transmitter dipole, the excitation current comprising a group of pulses of alternate polarity, each followed by zero current. The transient signal, which is produced thereby at the output of the receiver dipole, is repeatedly detected, and the transient signals are processed to obtain a figurative representation of the transient phenomenon which facilitates geophysical interpretation. Time intervals which are consecutive to excitation pulses and simultaneously with the excitation zero current are defined, these time intervals being of a predetermined duration, chosen to substantially cover all the useful parts of the transient phenomenon. The transient signal is detected as a function of time at least during the time intervals and is sampled, numbered and registered, temporally marked. A processing operation is carried out which commences with a preprocessing in which an unprocessed numerical representation of the transient phenomenon as a function…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.