Abstract: An equipment complex for deploying and recovering marine geophysical seismic or electric-survey bottom stations is mounted on a ship. The complex includes—a powered capstan, —rotatable turntables and rolls, —load-bearing units connected to the bottom stations by various fasten means and capable of winding onto the capstan and turntables, a work platform supporting a bottom station placed thereon, —an indicator for registration of the bottom stations' coordinates, mounted on the platform, —a limit switch mounted on the platform, switching ON when the bottom station is placed on the work platform, and OFF when it's removed therefrom providing for operation of the indicator. The complex may include floating buoys, damping loads, and halyards for deploying the stations. Methods for deploying and recovering the bottom stations using the equipment complex are described.

Abstract: An equipment complex for deploying and recovering marine geophysical seismic or electric-survey bottom stations is mounted on a ship. The complex includes—a powered capstan, —rotatable turntables and rolls, —load-bearing units connected to the bottom stations by various fasten means and capable of winding onto the capstan and turntables, a work platform supporting a bottom station placed thereon, —an indicator for registration of the bottom stations' coordinates, mounted on the platform, —a limit switch mounted on the platform, switching ON when the bottom station is placed on the work platform, and OFF when it's removed therefrom providing for operation of the indicator. The complex may include floating buoys, damping loads, and halyards for deploying the stations. Methods for deploying and recovering the bottom stations using the equipment complex are described.

Abstract: A sea bottom station for registration of seismic waves with vertical and horizontal components, having a vertical axis, including—a submergible case with a lid and a bottom preferably twice thicker than the lid,—a geophone block, wherein one geophone registers the vertical component, the remaining geophones register the horizontal component and create geophone pairs being pairwise orthogonal-positioned, while the geophones of each such pair are located symmetrically to the vertical axis. The bottom station includes—a power supply unit formed of rechargeable batteries, circumferentially located and pairwise symmetrical relatively to the vertical axis.

Abstract: The generator device is proposed for seabed survey, comprising a generator line, including electrodes, a hoist, hydraulic pump, air compressor, and at least one hose joined to the generator line, situated optionally inside or outside the line. The hose includes a through hydro-channel therein, a stationary end connected to the pump or alternatively to the compressor, and a running end furnished with a discharge valve. Connecting to the compressor ensures positive floatation of the generator line, whereas connecting to the pump ensures negative floatation thereof. In preferred embodiments, the device comprises a hydraulic clutch and a faucet. The hose communicates with the pump and compressor through the clutch and faucet, ensuring alternative communication of the hose's hydro-channel with water or air for filling thereof. The generator line comprises a dipole including one power braiding, and an initial part including two power braidings, the braidings are connected to the electrodes.

Abstract: A bottom system related to equipment deployed for seabed geo-electrical survey is proposed, in preferred embodiments comprising a basic module, including registration and power supply means, or a combination of the basic module with at least one additional module: a magnetic characteristics measuring module or/and a seismic characteristics measuring module. The additional modules are connected with other modules through hermetic connectors. The modules are attached to a load with Kevlar straps, provided with an electrochemical release system. Arms with electrodes measuring electromagnetic characteristics of seabed, are attached to the basic module, in their initial position directed upwards at minimum 15° from the vertical, and fixed with fixing elements, connected with a releasing element of a device for descending and lifting the bottom station. The arms are made telescopic for convenient transportation.

Abstract: A method for survey of hydrocarbon deposits in a researched profile of sea-bottom comprises providing a generator generating pulse electric current with a generator frequency in a towable generator line exciting electric field signals measured by sea-bottom stations synchronized with the generator, forming space-domain data arrays for the generator frequency and for higher odd harmonics frequencies nearest thereto, forming time-domain data arrays for selected offsets, inversion of the time-domain and space-domain data, and determining a bottom strata resistivity and polarization characteristics for the researched profile, based the inversion's results. The inversion preferably encompasses synchronizing and adjusting the generator line and electric field signals, dividing them into a frequency branch, including a fast Fourier transform and a robust summation producing the space-domain arrays, and a time-domain branch, including a robust summation producing the time-domain arrays.

Abstract: The proposed bottom station relates to geophysical exploration, particularly to the geo-electrical seismic survey equipment. It's intended for prediction of hydrocarbons deposits and study of the deep structure of earth's crust. The station comprises a body, a load, a registration device. The station is characterized by placement of sensors in the lower part of body, in combination with the use of the load, having a cavity on the upper surface with a diameter exceeding the corresponding body's diameter. The body is releasably fastened to the load by means of Kevlar ropes. Additional accuracy of the station is achieved by the use of orthogonal three-component sensors, rather than cardan sensors, as well as by incorporating into the station's body an additional acoustic system for control of location of the station. Substitution of a hard drive by a flush memory card in the registration device increases reliability of storing and transmitting information.

Abstract: A method for survey of hydrocarbon deposits in a researched profile of sea-bottom comprises providing a generator generating pulse electric current with a generator frequency in a towable generator line exciting electric field signals measured by sea-bottom stations synchronized with the generator, forming space-domain data arrays for the generator frequency and for higher odd harmonics frequencies nearest thereto, forming time-domain data arrays for selected offsets, inversion of the time-domain and space-domain data, and determining a bottom strata resistivity and polarization characteristics for the researched profile, based the inversion's results. The inversion preferably encompasses synchronizing and adjusting the generator line and electric field signals, dividing them into a frequency branch, including a fast Fourier transform and a robust summation producing the space-domain arrays, and a time-domain branch, including a robust summation producing the time-domain arrays.

Abstract: A sea electrical survey method for hydrocarbon deposits, situated under seabed not exceeding 10 meters of depth, is disclosed, comprising: providing a plurality of multi-channel bottom systems with receiving lines having at least three electrodes and capable to register electromagnetic signals, excitation devices generating a series of computer-controlled alternating-sign pulses, a horizontally positioned dipole, synchronizing the excitation devices and bottom systems, submerging the systems upon the seabed along a predetermined direction, aligning the receiving lines, moving the dipole within the survey zone, excitation of the pulses, registering signals, measuring the potentials difference and the spatial derivatives of the signals during the pulses and the pauses, recording data, analyzing the data with accounting the fields behavior in time and in space simultaneously, determining the environment resistivity and environment polarizability based on a predetermined mathematical model, and compiling the depo

Abstract: The generator device is proposed for seabed survey, comprising a generator line, including electrodes, a hoist, hydraulic pump, air compressor, and at least one hose joined to the generator line, situated optionally inside or outside the line. The hose includes a through hydro-channel therein, a stationary end connected to the pump or alternatively to the compressor, and a running end furnished with a discharge valve. Connecting to the compressor ensures positive floatation of the generator line, whereas connecting to the pump ensures negative floatation thereof. In preferred embodiments, the device comprises a hydraulic clutch and a faucet. The hose communicates with the pump and compressor through the clutch and faucet, ensuring alternative communication of the hose's hydro-channel with water or air for filling thereof. The generator line comprises a dipole including one power braiding, and an initial part including two power braidings, the braidings are connected to the electrodes.

Abstract: A bottom system related to equipment deployed for seabed geo-electrical survey is proposed, in preferred embodiments comprising a basic module, including registration and power supply means, or a combination of the basic module with at least one additional module: a magnetic characteristics measuring module or/and a seismic characteristics measuring module. The additional modules are connected with other modules through hermetic connectors. The modules are attached to a load with Kevlar straps, provided with an electrochemical release system. Arms with electrodes measuring electromagnetic characteristics of seabed, are attached to the basic module, in their initial position directed upwards at minimum 15° from the vertical, and fixed with fixing elements, connected with a releasing element of a device for descending and lifting the bottom station. The arms are made telescopic for convenient transportation.

Abstract: A method for electrical survey of hydrocarbons deposits under seabed depths up to 1500 m and equipment therefor are provided. The equipment includes a vessel, a generator, an excitation field block, connected with a vertical dipole with coax electrodes, a data registration/processing block, bottom systems with. The lower dipole electrode is situated at maximally 100 m from the seabed, the upper electrode at maximally 200 m from the surface. The operation of the generator and bottom systems is synchronized the dipole is submersed into the sea, and fed with alternating-sign rectangular current pulses, whose on-off time ratio and duration are programmably determined. The bottom systems register reflected signals and electromagnetic field components, when the dipole's current is on and off.

Abstract: A method for electrical survey of hydrocarbons deposits under seabed depths up to 1500 m and equipment therefor are provided. The equipment includes a vessel, a generator, an excitation field block, connected with a vertical dipole with coax electrodes, a data registration/processing block, bottom systems with. The lower dipole electrode is situated at maximally 100 m from the seabed, the upper electrode at maximally 200 m from the surface. The operation of the generator and bottom systems is synchronized the dipole is submersed into the sea, and fed with alternating-sign rectangular current pulses, whose on-off time ratio and duration are programmably determined. The bottom systems register reflected signals and electromagnetic field components, when the dipole's current is on and off.