An electromagnetic energy source for emitting pulses of electromagnetic energy includes a sonde assembly having a first section axially aligned with, and spaced from, a second section. An energy storage capacitor of the sonde assembly includes an electrode mounted in each of the first section and the second section of the sonde assembly and operable to generate an electric field, and a capacitive charge storage medium mounted in each of the first section and the second section of the sonde assembly and surrounding each electrode. The sonde assembly further includes a fast-closing switch located between the electrodes of the first and second sections of the sonde assembly.

A floating vessel based system generates a multidimensional seismic data set for a target area. The floating vessel based system includes a seismic source proximate to a floating vessel, providing a plurality of seismic energy pulses through water to the target area forming a plurality of reflected seismic energy pulses, a non-stationary seismic node configured for being towed from the floating vessel using at least one rope through the water, a non-stationary seismic node, and a second processor with second data storage on the floating vessel. The second data storage instructs the second processor to receive, each digital data series, combines the digital data series for all non-stationary seismic nodes utilized, and automatically generates multidimensional seismic data set for the target area.

A method for jointly inverting subsurface resistivities and noise parameters that may comprise the steps of identifying electromagnetic data acquired from one or more electromagnetic sensors, wherein the electromagnetic data includes a source-generated signal and noise, and jointly inverting at least subsurface resistivities and noise parameters based on the electromagnetic data. A marine electromagnetic survey system, that may comprise a data processing system configured to identify electromagnetic data acquired from one or more electromagnetic sensors, wherein the electromagnetic data includes a source-generated signal and noise and jointly invert subsurface resistivities and noise based on the electromagnetic data. A non-transitory machine-readable medium storing instructions executable by a data processing system that may cause the machine to identify electromagnetic data acquired from one or more electromagnetic sensors, wherein the electromagnetic data includes a source-generated signal and noise, and jointly invert subsurface resistivities and noise based on the electromagnetic data.

Various downhole logging tools and methods of using and making the same are disclosed. In one aspect, a downhole logging tool for inspecting one or more well tubulars includes a housing adapted to be supported in the one or more well tubulars by a support cable. A first transmitter, a second transmitter and a third transmitter are positioned in longitudinally spaced-apart relation in the housing and are operable to generate magnetic fields. Driving circuitry is operatively coupled to the first transmitter, the second transmitter and the third transmitter to selectively fire the first transmitter, the second transmitter and the third transmitter in multiple transmission modes to generate magnetic fields to stimulate pulsed eddy currents in the one or more well tubulars. A first receiver is positioned in the housing to sense decaying magnetic fields created by the pulsed eddy currents. Electronic circuitry is operatively coupled to the first receiver to determine a parameter of interest of the one or more well tubular from the sensed decaying magnetic fields.

Disclosed is a three-dimensional directional transient electromagnetic advanced detection device, wherein the CPU and the bus communication end of the transient electromagnetic transmitting module are both connected to the system bus, the signal output end of the transient electromagnetic transmitting module is connected to the transient electromagnetic transmitting coil outside the borehole to be detected, the signal input end of the electromagnetic signal receiving module is connected to the signal output ends of the three-dimensional magnetic field sensor and the one-dimensional Z-directional electric field sensor, the signal output end of the electromagnetic signal receiving module is connected to the electromagnetic signal input end of the SCM, the communication end of the first memory is connected to the data storage end of the SCM, the communication end of the three-dimensional electronic compass is connected to the compass signal communication end of the SCM, the host data communication of the SCM is connected to the second optical cable port of the local host through the first optical cable port and the optical cable. The device can detect harmful geological bodies such as aquifer and water-conducting channels and make a intensive and effective detection forecast.

Disclosed is a three-dimensional digital virtual imaging device for stratigraphic texture of borehole core, wherein the probe depth counting pulley is mounted on the lifting wire frame, the output shaft of the motor is configured to drive the reel to rotate, and one end of the cable is connected to the cable transfer node of the retractable reel, the signal input end of the borehole imaging trajectory measuring probe of the on-site imaging host is electrically connected to one end of the cable through the cable transfer node of the retractable reel, the cable is wound on the retractable reel, a retractable line is controlled by the retractable reel, the cable is extended and retracted on the probe depth counting pulley, the probe depth counting pulley records the length of the retractable line of the cable, the depth feedback signal output end of the depth counting pulley is connected to the depth feedback signal input end of the on-site imaging host, the motor control signal output end of the on-site imaging host is connected to the control signal input end of the motor, and the signal output end of the borehole imaging trajectory measuring probe is connected to the other end of the cable. It can automatically generate borehole video, two-dimensional digital virtual borehole core image and 3D borehole trajectory in real time.

A geophysical surveying method and assembly applying transient pulses of electric current to an airborne time-domain electromagnetic transmitter to generate a primary controlled electromagnetic field; measuring, using an airborne receiver, a secondary controlled electromagnetic field to generate controlled field data; measuring, using the airborne receiver, a magnetic component of a natural electromagnetic field at an above-ground position to generate first natural field data; measuring, using a ground receiver at a ground station, telluric electrical currents induced by the natural electromagnetic field and/or a magnetic component of the natural electromagnetic field at a ground position to generate second natural field data; merging the first natural field data and the second natural field data into combined natural field data; extracting, from the combined natural field data, off-time natural field data recorded between the pulses; and generating geophysical survey data based on the controlled field data and the off-time natural field data.

A method for signal communication between a well drilling instrument and the Earth's surface includes generating an electromagnetic field in an instrument disposed in drill string used to drill a wellbore. The electromagnetic field comprises encoded measurements from at least one sensor associated with the instrument. A signal is measured corresponding to an amplitude, phase or frequency of the electromagnetic field. The measurements are decoded from the measured signal. The measured signal comprises at least one of a voltage imparted across a capacitive electrode proximate ground surface and a galvanic electrode in contact with the ground surface, and a voltage imparted across two capacitive electrodes each proximate a ground surface and separated from each other by a known distance.

An electromagnetic energy source for emitting pulses of electromagnetic energy includes a sonde assembly having a first section axially aligned with, and spaced from, a second section. An energy storage capacitor of the sonde assembly includes an electrode mounted in each of the first section and the second section of the sonde assembly and operable to generate an electric field, and a capacitive charge storage medium mounted in each of the first section and the second section of the sonde assembly and surrounding each electrode. The sonde assembly further includes a fast-closing switch located between the electrodes of the first and second sections of the sonde assembly.

An electromagnetic energy source for emitting pulses of electromagnetic energy includes a sonde assembly having a first section axially aligned with, and spaced from, a second section. An energy storage capacitor includes an electrode mounted in each of the first section and the second section of the sonde assembly and operable to generate an electric field. A capacitive charge storage medium is mounted in each of the first section and the second section of the sonde assembly and surrounds each electrode, where the capacitive charge storage medium is a giant dielectrics and giant permeability ferrite. A fast-closing switch is located between the first and second sections of the sonde assembly.