Statoil Asa

Electromagnetic Geoservices As

Other

Den Norske Stats Oljeselskap A.s.

Norgas Geotekniske Institut

Norges Geotekniske Insitutt

Electromagnetic Geoservices Asa

Terje Eidesmo

Svein Ellingsrud

Harald Westerdahl

Fan-nian Kong

Tor Schaug-Pettersen

Stale Johansen

Vidar Sten-Halvorsen

Einar St&oslash;len

Jan-Aage Langeland

Anders Farestveit

Sylvia Sandra Pettersen, Legal Representative

Hans Magne Pedersen

A source arrangement for generating electrogmagnetic (EM) wavefields, comprising an EM signal generator, at least three electrodes (-) connected to the generator, and a control system. The electrodes are spaced apart but not all in line. The control system is arranged to apply non-coincident time-varying signals or transmissions from the generator between different pairs of the electrodes. The non-coincidence can be by applying the signals sequentially or by applying the signals out of phase.

Source arrangement and method for generating electromagnetic wavefields

A system for investigating subterranean strata. An electromagnetic field and a seismic event are applied from the same location and the responses are detected using respective receivers both located at a second location spaced from the first. The responses are combined to identify the presence and/or nature of subterranean reservoir. The refracted wave components are used.

Method and apparatus for determining the nature of submarine reservoirs

A system for detecting or determining the nature of a subterranean reservoir. An electromagnetic field is applied using a dipole antenna transmitter and this is detected using a dipole antenna receiver. The measurements are taken with the antenna both in-line and parallel and the difference between the two sets of measurements is exploited. A characteristic difference indicates a high resistive layer, which corresponds to a hydrocarbon reservoir.

Method and apparatus for determining the nature of subterranean reservoirs

The present invention relates to a system and apparatus for detecting and recovering hydrocarbons located in a subterranean reservoir In some embodiments, an electromagnetic field is applied by a transmitter positioned on a seabed and detected by antenna also positioned on the seabed.

Method and apparatus for recovering hydrocarbons from subterranean reservoirs

A method for mapping a submarine or subterranean reservoir by conducting an electromagnetic survey using an electromagnetic field in the form of a wave. An electromagnetic field is applied by a transmitter on the seabed and detected by antennae. The nature of the detected reflected waves is used to determine whether the reservoir contains water or hydrocarbons, which may then be produced from a well that penetrates the reservoir.

Electromagnetic surveying for mapping the content of subterranean reservoirs

A system for investigating subterranean strata. An electromagnetic field is applied using a dipole antenna transmitter and this is detected using a dipole antenna receiver. Phase information is extracted from a refracted wave response and used to identify the presence and/or nature of a subterranean reservoir.

Electromagnetic method and apparatus for determining the nature of subterranean reservoirs using refracted electromagnetic waves

A system for investigating subterranean strata. An electromagnetic field is applied using a fixed dipole antenna transmitter and this is detected using a dipole antenna receiver. The receiver is moved from one location to another in dependence upon the strength of the detected signal.

Electromagnetic methods and apparatus for determining the content of subterranean reservoirs

Methods and devices are disclosed for determining if hydrocarbons or water is present in a subterranean reservoir are described. Certain embodiments involve an electromagnetic field applied by a transmitter on the seabed and detected by at least one antenna also on the seabed, wherein a refracted wave component is sought in the wave field response, and is analyzed to determine the nature and contents of the resevoir.

Method and apparatus for determining the nature of subterranean reservoirs using refracted electromagnetic waves

A method for investigating subterranean strata. An electromagnetic field is applied using a dipole antenna transmitter and this is detected using a dipole antenna receiver. Phase information is extracted from a refracted wave response and used to identify the presence and/or nature of a subterranean reservoir.

The invention is a well radar for detecting, by electromagnetic wave reflection, resistivity horizons in production zones in oil wells. Transmitter and receiver antennas are combined in a tubing string antenna module. Two dipole transmitter antenna are positioned in a first position on either side of the tubing string antenna module. A first directionally sensitive group of four dipole receiver antennas is positioned in a second positioned so that the receiver antennas have even angular separation. Likewise, a second directionally sensitive group of four dipole receiver antennas is positioned in a third position opposite the first directionally sensitive group.

Device for electromagnetic detection of geological properties in a well

A system for determining the nature of a subterranean reservoir whose position and geometry is known from previous seismic surveys. An electromagnetic field is applied by a transmitter on the seabed and detected by antennea also on the seabed . The nature of the detected reflected waves is used to determine whether the reservoir contains water or hydrocarbons.

Method and apparatus for determining the content of subterranean reservoirs

A device for detecting changes of resistivity or dielectrical properties due to changes of fluid composition in the near-well area about a well in a geological formation, comprising an electrically conductive tubing string, an electrical energy source, a signal generator, at least one transmitting antenna for emitting electromagnetic waves along the tubing string, one or more receiver antennas for receiving electromagnetic waves reflected along the tubing string, devices for receiving signals induced in the receiver antennas, signal processing means for processing the received signals, and communication devices for transmitting signals representing the electrical signals and for receiving control signals.

Device and method for measurement by guided waves on a metal string in a well

A method for detecting electrical properties in a geological formation in a well which has within it a tubing string comprising the steps of mounting a transmitter antenna outside of the tubing string in a fixed position with respect to the geological formation, mounting a receiving antenna outside of the tubing string in a fixed position with respect to the geological formation, generating a first series of electromagnetic waves at a first time, receiving a first series of reflected electromagnetic waves in the receiver antenna, transforming the first series of reflected electromagnetic waves to form a first registration, generating a second series of electromagnetic waves at a second time, receiving a second series of reflected electromagnetic waves in the receiver antenna, transforming the second series of reflected electromagnetic waves to form a second registration, and comparing the registrations. Also disclosed is a device for accomplishing the method.

Growing community of inventors

Ranheim, Norway

Terje Eidesmo