RU2650849C1 - Autonomous seismo-acoustic station - Google Patents

Abstract

FIELD: geophysics.

SUBSTANCE: invention relates to geophysics and can be used for seismo-acoustic studies on the shelf while carrying exploration work for oil and gas deposits. Autonomous seismo-acoustic station (ASAS) is proposed, containing a carrier of equipment (CE), installed on the seabed, CE includes an onboard computer unit (OCU), power source, three-component pickup, as well as a hydrophone installed on the outside of the sealed container, the device for setting and removing the CE from the ground, means for searching for a floating CE, made in the form of a flashing light, a Glonass-type satellite navigation system, low-orbit satellite communication system of a type "Gonets" and active radar reflector, breaker, duplicated by commands from the urgency device, from the seal sensor, from the pressure sensor, recording path consisting of a four-channel filtering and amplifying unit that provides filtering of signals from the outputs of three-component pickups and a hydrophone in the 5-200 Hz frequency band and amplification of signals for their input to the input of the four-channel analog-digital converter unit, output signals from which are separately fed to the input channels of the former, where from the signals of the hydrophone and pickups an array of a single sample is formed with a length of sixteen-digit words fed from the output of the former to the corresponding channels of the information storage device, which is a solid-state memory of 4 flash cards with a capacity of 2 GB each, wherein the analog-digital converter unit consists of four 14-bit ADCs in which the apparatus carrier body is made of stressed reinforced concrete and has a surface part, on which a system of collecting and transferring ashore information from the measuring systems located at the seismic station is located. In this case, the carrier of the equipment is made in the form of separate annular monolithic sections, of stressed reinforced concrete and equipped with a guide (locks),

Inside the annular monolithic sections there are guide tubes for placing steel cables or rods in them for preliminary compression of a buoy body, jacks are placed in the lower part of the buoy, electric drive and strain gauges are placed in the buoy body.

EFFECT: technical result is more reliable seismic data.

1 cl, 2 dwg

Description

The technical solution relates to the constructive implementation of marine seismic research tools and can be used for long-term seismological studies.

The basic principles for constructing autonomous stations oriented to work at great depths are given in (Konovalov S.L.The use of autonomous bottom stations as a universal carrier for measuring equipment. Publishing House GP VNIFTRI, 2000, pp. 135-139 [1] ) Autonomous hydrophysical stations oriented to work at great depths, as a rule, are a robust equipment carrier body designed for a certain hydrostatic pressure and, accordingly, the maximum working depth. Inside the case there is electronic equipment, power supplies and measuring transducers. Transducers can also be located in remote systems, while communication with the equipment is carried out using cable glands. A fully equipped autonomous station should have positive buoyancy, and immersion is carried out due to the lost ballast weight, fixed to a controlled ballast disconnector.

Known autonomous bottom seismic station (ADSS) (patent RU No. 49286 U1, 10.11.2005 [2]), which is installed on the seabed at depths of up to 6000 m, is protected from the surrounding marine environment by a robust spherical body, equipped with a single hydrophone, digital recording system and information accumulation, telemetric hydroacoustic communication system, station search system on the sea surface, ballast release system, device for program control of operating modes.

The main disadvantage of ADSS is the possibility of registering only three components of seismic channels and significant weight and size characteristics of the equipment carrier (HA) and, as a result, a prerequisite for a supplying vessel is the presence of a powerful crane facility for performing production and sample work.

The experience of using GLONASS satellite navigation systems and Gonets communications was considered in a utility model of an autonomous seismic-acoustic hydrophysical station (ASAGS) (patent RU No. 61895 U1, 03/10/2007 [3]) when performing seismic-acoustic and hydrophysical monitoring over extensive sea areas. During the operation of ASAGS, special vessels are also required here, armed with cranes for carrying out staging and selective work. It is also known to use flash cards as information storage devices that are sequentially combined as a separate cassette (WO No. 201032947 A2, 03.25.2002 [4], US No.2002078297, 03.03.2010 [5], US No. 2007181699 A1, 09.08.2007 [ 6]). Also known ADSS (US No. 6560565 B2, 06/06/2003 [7], US No. 7016260 B2, 03/21/2006 [8], RU No. 2229146 C1, 05/20/2004 [9]) also have a number of significant drawbacks.

Also known is a small-sized autonomous seismic-acoustic station (MACAS), designed for offshore seismic-acoustic research when performing exploration of oil and gas fields (patent RU No. 2540454 C2, 02/10/2015 [10]), selected as a prototype.

The essence of the known technical solution [10] lies in the creation of the MASAS, which performs registration of seismic acoustic signals from the outputs of a three-component seismic receiver and hydrophone. To use the seamless geological model, the MASAS can be installed both on land and on the shelf at depths of up to 500 m. When working on land, MASAS can be used with the acoustic channel disconnected. Such a scheme of using the MASAS allows conducting wide area studies using the methods of CMPW and MOB. When performing on-site exploration, dozens of synchronously operating MASAS are required. Therefore, the following requirements are imposed on MASAS: simplicity in operation; relatively low cost; small weight and size parameters, allowing manual station production and sampling using small vessels. Reliable station return is provided using: duplicate actuator commands; light beacons; active beacons; a satellite navigation system of the Glonass type and a low-orbit satellite communication system of the Gonets type. The capacity of continuous recording of digitized information up to 60 days, which is ensured by a solid-state memory of 4 flash cards with a capacity of 20 GB each. The modern elemental base allows to significantly reduce the weight and size parameters of devices. MASAS has the following weight and size parameters: outer diameter of the carrier - 350 mm; station weight - 13 kg; ballast weight - 20 kg. Known MASAS [10] is (Fig. 2 and Fig. 3 prototype) an ellipsoid structure (working depth up to 500 m) equipment carrier (ON), consisting of two hemispheres and a cylindrical insert (upper hemisphere made of radiolucent materials, lower the hemisphere is made of aluminum alloys, between the hemispheres a cylindrical insert made of aluminum alloys), tightened with bolts on the flanges, to ensure tightness on special grooves cut in a circle, two rubber sealing rings are laid. Inside the AT are installed: receiving antennas of satellite navigation and communication systems; on-board computing unit (STB) with an information storage device mounted on the instrument ring; on the lower hemisphere - a power source; two horizontal and vertical components of the seismic receiver and an urgency device (PS) located in the housing, and an electrochemical disconnector, the executive part of which is brought out to a special area of the lower hemisphere. Outside, on the upper hemisphere, on special sites of the upper square frame, the following are installed: hydrophone; radar reflector antenna; flashing beacon (PM). A device for rigid landing on the ground, made of metal pipes, rigidly pulled together with the help of the actuator part of the disconnector, is attached to the area of the lower square frame; ballast shoes are attached to the sole of the device. When the MACAS ascends, the device with ballast shoes remains at the bottom. The power source is assembled from lithium rechargeable batteries, which currently provide the maximum capacity per standard unit of weight and size batteries. The power source is installed so that the center of gravity of the assembled station is located on the lower hemisphere to ensure the stability of the station on the sea surface. To ensure reliable stability of the MACAC on the sea surface when working with satellite navigation and communication systems, an additional load is fixed on the lower part of the hull. When sampling the MASAS on board the vessel, a special capture device is used, the base of which is rigidly fixed to the platform of the upper square frame, and the tip is attached to the end of the halyard, the other end of the halyard is attached to the float. In the transport version, the halyard is wound on a float with a halyard length of 15-20 m. The stand-alone urgency device is an electronic timer with an autonomous power source for directly actuating the actuator of the disconnector.

When a current is applied to the circuit breaker, the electrochemical-type disconnect mechanism operates for several minutes, thereby freeing the MACAS from a hard-landing device with ballast shoes.

Possessing significant advantages over similar technical solutions [1–9] in terms of performing the MASAS in a small-sized version, at the same time, the well-known MASAS [10] has significant disadvantages. The main disadvantage is that the ballast is made in the form of shoes.

When placing the carrier of the measuring equipment on an uneven bottom, as well as in the presence of underwater currents, the carrier of the measuring equipment may take an unstable position, and when combined with adverse underwater conditions, it may fall on its side.

In addition, the presence of hard landing devices spaced apart by small distances in the presence of underwater currents can cause the appearance of unwanted additional acoustic noise.

The disadvantages include the placement of the equipment carrier directly on the hard landing device, which does not allow excluding the influence on the quality of registration of seismic signals of bottom currents, which swing the hard landing device together with the carrier of the equipment, and causes vortex noise around thin-sized elements of the underwater structure.

The use of tools to search for a pop-up ND made in the form of a flashing beacon, a satellite navigation system of the Glonass type, a low-orbit satellite communication system of the Gonets type and an active radar reflector leads to an increase in labor costs in the manufacture of MACAS, and the resulting positive effect cannot always to be achieved.

The disadvantages include the high cost, the complexity and the duration of the service in the process of lifting the station to the ship, the low streamlining of the hull of the station, which causes undesirable turbulence, a limited life, which is due to the corrosion resistance of the metal hull in sea water.

In modern domestic (and foreign) marine practice, a number of trends are observed, expressed in the preference for certain types of equipment carriers. This is due to the general development of marine technology (including military), with the growing demands of marine technology (mining from the bottom), and great successes in instrumentation.

One of the directions is to reduce the size and weight of underwater equipment, and hence the size of equipment carriers, while increasing the time of work at sea (up to several months and years). Another direction is the reduction in the cost of equipment carriers and the time for their maintenance, which is caused by their massive use as part of the corresponding complexes (during seismic exploration for oil and gas on the shelf and on the continental slope, with environmental protection of water areas in industrial development sites, with tomographic studies of the ocean, etc. .). The cost of equipment carriers is currently comparable to the cost of electronic equipment used, and often more.

The objective of the proposed technical solution is to increase the durability of the recording medium of seismic signals, while reducing labor costs and expanding functionality.

The problem is solved due to the fact that in an autonomous seismic-acoustic station containing an equipment carrier installed on the seabed, which includes an on-board computing unit located in a sealed spherical container, a power source, a three-component seismic receiver, as well as a hydrophone mounted outside the sealed container, and a setting device and removing the equipment carrier, satellite navigation system of the Glonass type, low-orbit satellite communication system of the Gonets type and active a radar reflector, a recording path consisting of a four-channel filtering and amplification unit, providing filtering of the signals from the outputs of the three-component geophones and a hydrophone in the frequency band of 5-200 Hz and amplification of the signals for supplying them to the input of the four-channel analog-to-digital converter unit, the output signals from which separately fed to the input channels of the shaper, where an array of a separate sample with a length of sixteen-bit words is formed from the signals of the hydrophone and geophones, coming from the output of the shaper's channels to the corresponding channels of the information storage device, which is a solid-state memory of 4 flash cards with a capacity of 2 GB each, and the four-channel analog-to-digital converter unit consists of four 14-bit ADCs - the housing of the equipment carrier is made of reinforced concrete and has a surface part, which houses a system for collecting and transmitting ashore information from measuring systems located at a seismic station, including an automatic marine meteo a plant located at a height of 1 Ohm from the sea surface, atmospheric sensors for measuring wind speed, temperature and humidity, located from the sea surface to a height of 15 m for measuring profiles in the drive layer of the atmosphere and calculating momentum, heat and moisture flows, a video system for measuring surface characteristics waves, a string waveograph for measuring the height and shape of waves, measuring instruments for descending and ascending radiation to assess the radiation balance, there is a thermal on the buried part of the body of the equipment carrier an wasp with the location of the sensors (after 1 m) from the surface up to 40-50 m in depth, made in the form of fiber-optic hydrophones, and the apparatus carrier body made of stressed reinforced concrete is made in the form of separate annular monolithic sections, made of stressed reinforced concrete and equipped with guides (locks), guide tubes are located inside the annular monolithic sections, for placement of steel cables or rods in them for preliminary compression of the buoy body, jacks are placed in the lower part of the buoy, ele drive and strain gauges.

Blocks and devices that implement the corresponding signs of the restrictive part of the known technical solutions can be performed similarly to the corresponding blocks and devices of the prototype [10].

Unlike the prototype [10], in the proposed technical solution, the housing of the equipment carrier is made of stressed reinforced concrete.

At the same time, the apparatus carrier body is made in the form of separate annular monolithic sections, of reinforced concrete and equipped with guides (locks), guide tubes are located inside the annular monolithic sections, for placement of steel cables or rods in them for preliminary compression of the buoy body; jacks, electric drive and strain gauge sensors are placed in the body of the buoy.

The equipment carrier body has a surface part, on which the system for collecting and transmitting information from measuring systems located at the seismic station to the shore, an automatic marine weather station located at a height of 1 Ohm from the sea surface, atmospheric sensors (wind speed, temperature and humidity) are placed located from the sea surface to a height of 15 m for measuring profiles in the drive layer of the atmosphere and calculating the momentum, heat and moisture flows, a video system for measuring the characteristics of surface waves, strings A wave recorder for measuring wave height and waveform, downward and upward radiation meters for assessing radiation balance, there is a thermocosa on the buried part of the equipment carrier body with sensors located (after 1 m) from the surface up to 40-50 m in depth, made in the form of fiber-optic hydrophones. The housing of the equipment carrier is made of reinforced concrete, which has increased density and water resistance, for example, NTs-10 or NTs-20 brands (iPo Beton.ru> vidy / napryagayushhij_cement.html, neradr.ru> staty / napryagayuschiy_cement_-chto-eto ... ▼ )

The total length of the equipment carrier is 45 m, the length of the underwater part is 30 m, and the diameter is 2.4 m, the length of the surface part of the hull is 3 m, and the mast is 12 m. The size of the mast in plan in axes: 1.6 × 1.6 m. The total mass of the equipment carrier is 103.6 tons. The height of the ballast column (water) is ≈10 m. Natural vibration frequencies: vertical 0.09 Hz; inclined 0.05 Hz. The buoy is made in the form of separate annular monolithic sections, inside of which guide tubes are placed, for placement of steel cables or rods in them for preliminary compression of the buoy body.

To ensure the alignment of the tube holes between the sections and the convenience of assembling the buoy, the sections are equipped with special guides (locks).

For the convenience of manufacturing and transportation to the place of setting, the buoy is made in the form of separate ring sections.

After the buoy is assembled, cables (rods) inserted into the tubes are fixed at one end of the buoy and are pulled with jacks at the other end of the buoy, providing a mode of preliminary compression of concrete. Strain gages are placed in the body of the buoy for continuous measurement of stresses. In the case of a decrease in concrete compression below a predetermined level (for example, due to stretching of the cables), the electric drive of the jacks is turned on to achieve the necessary efforts.

The system of collecting and transmitting information from measuring systems located on the equipment carrier to the shore includes an automatic marine weather station located at a height of 10 m from the sea surface, atmospheric sensors (wind speed, temperature and humidity) located from the sea surface to a height of 15 m for measuring profiles in the drive layer of the atmosphere and calculating the momentum, heat and moisture flows, a video system for measuring the characteristics of surface waves, a string wave recorder for measuring the height and shape of waves, low-speed meters rising and rising radiation for assessing radiation balance, a thermobox with sensors located (after 1 m) from the surface to 40-50 m depth, an automatic winch for performing soundings from the surface to the bottom with a STD probe and additional sensors (chlorophyll fluorescence “a”, concentration suspension, dissolved oxygen, nitrates), an acoustic local flow velocity meter, an underwater video camera with illumination for observing dolphins, fish and other biological objects, bottom cable seismic acoustic stations for Measurements sea noise, acoustic imaging and recording local and distant earthquakes, automatic identification system vessels (AIS), a translator for mobile communication (Biline, megaphone).

Such a carrier of equipment can be used for a wide range of marine research, as well as carriers for the basic equipment of marine network communications. The manufacture of equipment carriers from reinforced concrete provides a lower cost (about 4 times compared with the metal equipment carriers), greater environmental safety, ease of manufacture and transportation to the place of setting. Such an equipment carrier can be equipped with sufficiently powerful power sources. It has a mast up to 15 m above sea level, which can provide a cellular communication range of over 20 km. The approximate cost of the buoy (without equipment) is two million rubles.

Using 10-15 such carriers of equipment - repeaters, you can create a marine cellular communication system, for example, along the northeast coast of the Black Sea from Novorossiysk to Sochi with a communication range from the coast of up to 50 km. At the same time, a significant amount of other equipment can be placed on them to solve a wide range of scientific, technical and applied tasks related to the sea. The essence of the proposed technical solution is illustrated by drawings.

FIG. 1. Schematic representation of the media equipment. The body of the equipment carrier includes a surface 1 and underwater 2 parts located on the sea surface 3.

A satellite antenna 4, an automatic marine weather station 5 located at a height of 10 m from the sea surface, and atmospheric sensors (wind speed, temperature and humidity) 6 located from the sea surface to a height of 15 m for measuring profiles in the atmospheric drive layer and the calculation of momentum, heat and moisture flows, a video system 7 for measuring the characteristics of surface waves, a string wave recorder 8 for measuring the height and shape of the waves, measuring instruments 9 descending and ascending for assessing the radiation balance, batteries 10, translator 11 for mobile communications (Beeline, Megafon), on the indented part 2 of the apparatus carrier body, there is a thermobox 12 with sensors located (1 m from the surface to 40-50 m depth, made in the form fiber-optic hydrophones, automatic winch 13 for sounding from the surface to the bottom of the STD - probe 14 and additional sensors (fluorescence of chlorophyll “a”, concentration of suspended matter, dissolved oxygen, nitrates) 15, acoustic local meter 16 current speeds, an underwater video camera 17 with backlight for observing dolphins, fish and other biological objects.

The buoy is made in the form of separate annular monolithic sections 18, inside of which guide tubes 19 are placed to accommodate steel cables 20 or rods for preliminary compression of the buoy body.

To ensure the alignment of the holes of the tubes 19 between the sections 18 and the ease of assembly of the buoy, the sections 18 are equipped with special guides (locks) 21. For the convenience of manufacture and transportation to the place of setting, the buoy is made in the form of separate ring sections 18.

After the buoy is assembled, the cables (rods) 20 inserted into the tubes 19 are fixed at one end of the buoy and are tensioned with jacks 22 at its other end, providing a mode of preliminary compression of concrete. In the body of the buoy placed strain gauge sensors 23 for continuous measurement of stress. In the case of a decrease in concrete compression below a predetermined level (for example, due to stretching of the cables), the electric drive 24 of the jacks 22 is turned on to achieve the necessary efforts.

On the seabed 25, bottom cable seismic acoustic stations 26 are located for measuring sea noise, acoustic tomography and recording local and remote earthquakes, an automatic ship identification system (AIS) 27 connected to the station via a cable cable or via a hydroacoustic communication channel.

FIG. 2. Appearance of the equipment carrier in the working position.

The work of an autonomous seismic acoustic station is as follows. On board the supply vessel, before the station is set up, a full training cycle takes place, which includes the inclusion and testing of various units and blocks, and entering the station's work program into the software device. After the preparation cycle, the station is lowered from the side of the supply vessel overboard using an external crane. Acoustic seismic signals are received using a hydrophone and three-component seismic receivers oriented in three orthogonal directions X, Y, Z. Signals are recorded on multichannel recorders.

By means of an automatic marine weather station 5 located at a height of 10 m from the sea surface, and by means of atmospheric sensors 6 located from the sea surface to a height of 15 m, wind speed and direction, temperature, humidity, atmospheric pressure, and profiles in the drive layer of the atmosphere are measured and determined flows of momentum, heat and moisture. By means of the video system 7, the characteristics of surface waves are measured, and by means of the string waveograph 8, the height and waveforms are measured. Using meters 9 set downward and upward radiation to assess the radiation balance. By means of a thermocover 12 with sensors located on it (after 1 m) from the surface to 40-50 m in depth, made in the form of fiber-optic hydrophones, signals of seismic origin are recorded, which are further processed by known methods to identify seismic processes in the interest of preventing underwater earthquakes and the search for underwater minerals. Automatic winch 13 is designed to move measuring sensors when performing soundings from the surface to the bottom of the STD - probe 14 and sensors (fluorescence of chlorophyll "a", suspension concentration, dissolved oxygen, nitrates) 15.

An acoustic local meter 16 for the speed of currents is designed to determine the speed and direction of underwater currents, and an underwater video camera 17 with illumination, for observing dolphins, fish and other biological objects.

On the seabed 25 there are bottom cable seismic and acoustic stations 26 for measuring sea noise, acoustic tomography and recording local and remote earthquakes, an automatic ship identification system (AIS) 27, which are electrically and mechanically connected via cable cables to the respective registrars.

The proposed technical solution in comparison with the prototype provides increased durability of the recording medium of seismic signals, while reducing labor costs and expanding functionality.

As measuring means, industrially mastered products can be used.

Information sources

1. Konovalov S.L. The use of autonomous bottom stations as a universal carrier of measuring equipment. Publishing House of the State Enterprise "VNIFTRI", 2000, p. 135-139.

2. Patent RU№49286 U1, 10.11.2005.

3. Patent RU No. 61895 U1, 03/10/2007.

4. Application WO No.201032947 A2, 03.25.2002.

5. Application US No.2002078297, 03/25/2010.

6. Application US No. 2007181699 A1, 08/09/2007.

7. US patent No. 6560565 B2, 05/06/2003.

8. US patent No. 7016260 B2, 03.21.2006.

9. Patent RU No. 2229146 C1, 05.20.2004.

10. Patent RU No. 2540454 C2, 02/10/2015.

Claims (2)

1. An autonomous seismic-acoustic station containing an equipment carrier installed on the seabed, which includes an on-board computing unit located in a sealed spherical container, a power source, a three-component seismic receiver, as well as a hydrophone installed on the outside of the sealed container, an apparatus for setting up and removing the equipment carrier, and a satellite system Glonass-type navigation, a low-orbit satellite communications system of the Gonets type and an active radar reflector, recording a path consisting of a four-channel filtering and amplification unit that filters the signals from the outputs of three-component geophones and a hydrophone in the frequency band 5-200 Hz and amplifies the signals to feed them to the input of the four-channel analog-to-digital converter unit, the output signals of which are separately fed to the input shaper channels, where an array of a separate sample with a length of sixteen-bit words is fed from the hydrophone and geophones signals from the output of the shaper channels to corresponding channels of the information storage device, which is a solid-state memory of 4 flash cards with a capacity of 2 GB each, and the four-channel analog-to-digital converter unit consists of four 14-bit ADCs, characterized in that the housing of the equipment carrier is made of stressed reinforced concrete and has a surface the part that houses the system for collecting and transmitting information from measuring systems located on the seismic station to the shore, including an automatic marine weather station located on at a height of 10 m from the sea surface, atmospheric sensors for measuring wind speed, temperature and humidity, located from the sea surface to a height of 15 m for measuring profiles in the drive layer of the atmosphere and calculating the momentum, heat and moisture flows, a video system for measuring the characteristics of surface waves, string wave recorder for measuring the height and shape of the waves, measuring instruments for downward and upward radiation to assess the radiation balance, on the indented part of the carrier body of the equipment there is a thermocosa with the location of the sensor s (after 1 m) from the surface to 40-50 m depth, made in the form of fiber optic hydrophones. 2. The stand-alone seismic-acoustic station according to claim 1, characterized in that the apparatus carrier body is made in the form of separate annular monolithic sections of reinforced concrete and provided with guides (locks), guide tubes are located inside the annular monolithic sections to accommodate steel cables or rods in them for preliminary compression of the buoy body, jacks are placed at the bottom of the buoy, an electric drive and strain gauge sensors are placed in the body of the buoy.

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