Abstract: A vertical receiver antenna device includes first and second receiving, electrode units interconnected by a receiver antenna cable and connected to means for the electromagnetic surveying of electrically resistive targets potentially containing hydrocarbons. The receiver antenna is arranged in a tubular, non-magnetic antenna housing arranged vertically in subsea uncompacted material, and one of the first and second receiving electrode units being connected in a electrically conductive manner to the underlying structure, and the other one of the first and second receiving electrode units being arranged in a portion of the antenna housing distantly from the first one of first and second receiving electrode units.

Abstract: A device for disposing an antenna dipole arranged to be submerged in a water mass is described. A first electrode is placed, in an operative position, approximately vertically above and at a distance from a second electrode. A mast is pivotally secured, at a portion distant from, in the operative position, a lower end portion, to a stand. The first electrode is arranged near, in or on an upper end portion of the mast. The second electrode is arranged near, in or on the lower end portion of the mast. The mast and/or stand includes means which are arranged to keep the mast in a prescribed position. The mast and stand are formed substantially of non-magnetic materials.

Abstract: This application relates to a method and apparatus for the acquisition, processing and inversion of marine control source electro magnetic (CSEM) data. A system provides data acquisition and processing of the responses measured simultaneously by multiple receivers placed in a near zone and partly in the intermediate zone at different distances around the transmitter.

Abstract: A system for offshore hydrocarbon electromagnetic prospecting is described. The system includes a transmitter generating electromagnetic energy and injecting an electrical current into a flooded vertical cable. Electromagnetic fields generated by this current in the medium are measured by total field magnetometers or gradiometers. The measured response, which is sensitive to the resistivity of targets, is used to search for and identify hydrocarbon reservoirs. A method for offshore hydrocarbon electromagnetic prospecting is described as well.

Abstract: A system for offshore hydrocarbon electromagnetic prospecting is described. The system includes a transmitter generating electromagnetic energy and injecting an electrical current into a flooded vertical cable. The circulated induced vertical current time derivative's response generated by this current in the medium is measured by a circular chain of magnetometers. The measured response which is sensitive to the resistivity of targets is proposed to be used to search for and identify hydrocarbons reservoirs.

Abstract: A device for disposing an antenna dipole arranged to be submerged in a water mass is described. A first electrode is placed, in an operative position, approximately vertically above and at a distance from a second electrode. A mast is pivotally secured, at a portion distant from, in the operative position, a lower end portion, to a stand. The first electrode is arranged near, in or on an upper end portion of the mast. The second electrode is arranged near, in or on the lower end portion of the mast. The mast and/or stand includes means which are arranged to keep the mast in a prescribed position. The mast and stand are formed substantially of non-magnetic materials.

Abstract: A vertical receiver antenna device includes first and second receiving electrode units interconnected by a receiver antenna cable and connected to means for the electromagnetic surveying of electrically resistive targets potentially containing hydrocarbons. The receiver antenna is arranged in a tubular, non-magnetic antenna housing arranged vertically in subsea uncompacted material, and one of the first and second receiving electrode units being connected in a electrically conductive manner to the underlying structure, and the other one of the first and second receiving electrode units being arranged in a portion of the antenna housing distantly from the first one of said first and second receiving electrode units. A method of installing a vertical receiver antenna in subsea uncompacted material is also described.

Abstract: A method for processing, transforming and mapping subsea survey data arranged to detect earth formations including hydrocarbon reservoirs is proposed. The method differs from known methods by including a real configuration of the sounding system and parameters for a given area of a reference model and by a method for processing and transforming the measured signals.