Abstract: The invention relates to a device for determining petrophysical parameters of an underground formation, comprising at least two electrodes (EL), a means for emitting a frequency-variable electric current (MEC), and a means for measuring electrical resistivity (MRE) in terms of amplitude and phase, two of the electrodes (EL) cooperating with the emission means (MEC) and at least two of the electrodes (EL) cooperating with the means for measuring resistivity (MRE), a means for measuring a difference in electrical potential (MDP) cooperating with at least two of the electrodes (EL). The invention is particularly applicable to oil exploration and development.

Abstract: Method of exploiting and/or of monitoring the exploitation of a fluid such as a hydrocarbon fluid present in at least one geologic layer of an underground formation. From consecutive pressure and spontaneous potential measurements taken at least at one measurement point in at least one well drilled through at least the geologic layer of interest, the slope of a curve showing the evolution of the spontaneous potential gradient as a function of the pressure gradient is determined. Then, from this slope and from a graph representative of the evolution of the electrokinetic coupling coefficient as a function of the salinity for the layer considered, a salinity value is determined at the measurement point.

Abstract: Method of exploiting and/or of monitoring the exploitation of a fluid such as a hydrocarbon fluid present in at least one geologic layer of an underground formation. From consecutive pressure and spontaneous potential measurements taken at least at one measurement point in at least one well drilled through at least the geologic layer of interest, the slope of a curve showing the evolution of the spontaneous potential gradient as a function of the pressure gradient is determined. Then, from this slope and from a graph representative of the evolution of the electrokinetic coupling coefficient as a function of the salinity for the layer considered, a salinity value is determined at the measurement point.

Abstract: A facility for monitoring a geological storage site for storing a gas, such as CO2 or methane, comprises, in combination, at least one geochemical measurement device (DMG), comprising a plurality of gas sampling probes (SPG) connected to a gas analyzer (AG), an electrical measurement device (DME) comprising a plurality of electrodes (ELEC) and a resistivity meter (RES), and a meteorological station (SM). The geochemical and electrical measurement devices are controlled by a logic controller (AUT). The geochemical and electrical measurement devices and the meteorological station are connected to a data collector (COLL) that is itself connected to means for transmitting said data (MTD).

Abstract: The invention relates to a device for determining petrophysical parameters of an underground formation, comprising at least two electrodes (EL), a means for emitting a frequency-variable electric current (MEC), and a means for measuring electrical resistivity (MRE) in terms of amplitude and phase, two of the electrodes (EL) cooperating with the emission means (MEC) and at least two of the electrodes (EL) cooperating with the means for measuring resistivity (MRE), a means for measuring a difference in electrical potential (MDP) cooperating with at least two of the electrodes (EL). The invention is particularly applicable to oil exploration and development.

Abstract: A device for monitoring an formation below the ground G containing a fluid such as CO2 or methane comprising a measuring cell arranged in a cavity, can an F analyzer disposed on the surface and a sealed connection connecting measuring cell to the analyzer. The measuring cell comprises two chambers that can sealingly communicate with one another. The first chamber comprises a plurality of orifices allowing passage of the fluid into first chamber, at least two inner electrodes and fluid circulator. The second chamber is impervious to the fluid. Applications include monitoring of geological storages sites for gas such as CO2.

Abstract: A facility for monitoring a geological storage site for storing a gas, such as CO2 or methane, comprises, in combination, at least one geochemical measurement device (DMG), comprising a plurality of gas sampling probes (SPG) connected to a gas analyser (AG), an electrical measurement device (DME) comprising a plurality of electrodes (ELEC) and a resistivity metre (RES), and a meteorological station (SM). The geochemical and electrical measurement devices are controlled by a logic controller (AUT). The geochemical and electrical measurement devices and the meteorological station are connected to a data collector (COLL) that is itself connected to means for transmitting said data (MTD).

Abstract: A device for monitoring an underground formation containing a fluid such as CO2 or methane comprising a measuring cell (CM) arranged in a cavity, analysis means (MA) arranged on the surface and sealed connection means (ML) connecting measuring cell (CM) to analysis means (MA). The measuring cell comprises two chambers (CH1, CH2) that can sealingly communicate with one another. The First chamber (CH1) comprises a plurality of orifices (OR) allowing passage of the fluid into first chamber (CH1), at least two inner electrodes (EI) and fluid circulation means (MC). Second chamber (CH2) is impervious to the fluid.