Mobile self-contained underwater seismic-hydroacoustic station for exploration of hydrocarbons on water area of arctic shelf

FIELD: physics; geophysics.

SUBSTANCE: invention relates to devices for seismic exploration of hydrocarbon deposits on the water area of the arctic shelf. The mobile self-contained underwater seismic-hydroacoustic station for exploration of hydrocarbons on the water area of the arctic shelf has a hard, streamlined housing, a power plant, a motor, a gyroscope, a distance measuring device, an echo sounder, a depth sensor, a hydroacoustic beacon signal locator, buoyancy control means and an on-board computer with a program device for controlling movement of the station from one point on the sea to another, hovering, sinking to the bottom, raising from the bottom to a given depth and onto the sea surface.

EFFECT: designing a mobile underwater self-contained seismic-hydroacoustic station for exploration of hydrocarbons, capable of independently moving according to a given program to investigated points on the sea, hovering over said points, sinking to the bottom and raising from the bottom to a given depth while simultaneously reducing self-generated seismic-hydroacoustic noise.

1 dwg

 

The present invention relates to a device for prospecting of hydrocarbon deposits on the Arctic shelf.

Currently developing device of seismic exploration using non-explosive sources of seismic energy. This device is intended for the reception of microseisms of the seabed, which carry useful information about the deep structure of the seabed, including information about the presence of hydrocarbon deposits.

A device for seismic exploration of hydrocarbons, consisting of bottom stations with geophones and scuba apparatus, alternately podplyvali to them and collect from them information on the hydroacoustic channel (Svemirskoj. On the application of Autonomous unmanned underwater vehicles technology total bottom seismic. // Proceedings of the 4th all-Russian scientific-technical conference "Technical problems of development of the World ocean", Section 2, 2011, Vladivostok, s-224).

The disadvantage of this solution is that by this method of exploration in addition to the submersible must be installed on the bottom of the large number of bottom stations (up to 220 units)to which the sub alternately come and polls. This arrangement of devices for seismic increases the cost of the seismic survey because of the need to install a large Koli is esta expensive seismic stations and the complexity of their installation and lifting, especially in areas with a muddy bottom and in the presence of the ice cover. This device does not provide for its installation in the bottom layer of the sea.

Another analog is the invention according to the patent of Russian Federation №2438149 "Autonomous bottom stations for seismic observations". The station consists of a sealed enclosure, bottom geophone sensor spatial orientation, beacon, ballast, NC ballast, analog amplifiers and filters low frequency, block the exact time and digital recorder.

The disadvantage of this technical solution to be used in Arctic conditions is the difficulty of installation of seismic stations on the bottom of the sea under the ice cover and, especially, permutations of seismic stations in the other measurement points on the bottom with powerful ice cover. Also not provided for the installation of seismic stations in the bottom layer of the sea.

The closest analogue, that is, the prototype is the invention according to the patent of Russian Federation №2435180 Underwater geophysical station".

The essence of this invention lies in the fact that the submarine geophysical station has a sealed housing made of high strength aluminum alloy with a protective corrosion-resistant coating, seismogenic, means of recording and storing information.

The disadvantage of the prototype are previously mentioned the difficulties of installation and rearrangement of bottom stations at other points on the bottom of the sea with powerful ice cover. It is also not possible to add in the bottom layer of the sea.

Note that currently there is no information about the stations, able to move independently to measure from one point of the sea to another point, to hang over her, and then to lie on the ground of the sea bottom and to rise from the bottom to a predetermined depth. Besides the measurements on Board the mobile underwater station is difficult because of interference with the flow. These interference mask microseisms from hydrocarbon and prevent their detection.

The purpose of this invention is to provide a mobile Autonomous underwater seismogeological station of hydrocarbon exploration, able to move independently according to a given program in the study of sea point, hover over them to sink to the bottom and go up from the bottom to a predetermined depth while reducing their own seysmogydroaquistic interference.

This goal is achieved by the fact that mobile Autonomous underwater seysmogidrodinamicheskie station of hydrocarbon exploration in the waters of the Arctic shelf is additionally equipped with a rugged, streamlined, power plant, propeller, gyroscope, fuel gauge path, depth sounder, depth sensor, locator signals sonar beacon, means of regulating the buoyancy and the onboard is a computer software device motion control station from one point of the sea to another, hang on, the descent to the bottom, rise from the bottom to the specified depth and at the surface of the sea.

The combination of these features ensures the achievement of this goal.

The proposed device is illustrated by a drawing, which shows a diagram of a mobile Autonomous underwater seismogeological station, where:

1 - rugged streamlined;

2 - gyro;

3 - meter path;

4 - sounder;

5 - the depth sensor;

6 - Board computer software device management;

7 - seismogenic;

8 - a means of providing buoyancy;

9 - power installation;

10 - mover;

11 - locator signals sonar beacon.

Underwater station depending on ice conditions is delivered with the help of surface or underwater hydro vessel in the area of the first target point and is available in swimming. Possible lowering of the station into the hole with ice.

Underwater station has rugged streamlined (POS.1). Depending on the indications gyro (2)meter path (3), echo sounder (pos.4), depth sensor (5) on-Board computer device (pos.6) provides the following modes of operation: move from one point sea to another, hang, descent to the bottom and rise from the bottom to the specified depth. The field and the test was established, that microseisms of the seabed can be registered by seismographs are not only at the bottom, but in the bottom layer of water. This explains the complex sequence of dimensions: hangs at the descent to the bottom and on the bottom.

To perform these operation modes is selected mover (10), for example an electric motor, and power setting (position 9), for example a battery, and means for regulating the buoyancy (pos.8). Adjusting the buoyancy is in the range from zero buoyancy to negative or positive buoyancy. In hang mode station is moved over together with the water environment, which reduces hydrodynamic interference flow and facilitates the recognition of microseisms from hydrocarbon fields. Seismogenic (pos.7) allows measurement of individual projections of the vector oscillating speed (acceleration, displacement, or derivatives thereof), and all at the same time. In the process hangs and smooth dive to the bottom and when at the bottom of the geophone signals are recorded in digital form.

Further, these data are used in an inpatient treatment center or on Board the vessel when interpreting results to determine the signs of the presence of hydrocarbon deposits.

After completion of measurements of the underwater station returned to the area first examine the second point and the computer sends a signal to switch on the locator signals sonar beacon (11) for detecting beacon (submarine or surface ship or lighthouse, drop from the ice at the point of deployment) and the approach to the lighthouse and the lift station on geophysical vessel or on the ice.

Technical and economic effect is to reduce the complexity and cost exploration equipment, as u mobile station and is a measure of microseisms and does not require additional benthic stations.

Unlike mini-submarine with a crew declared an underwater station has considerably smaller dimensions and considerably lower cost. In unmanned stations eliminated the problem of security people.

Mobile Autonomous underwater seysmogidrodinamicheskie station of hydrocarbon exploration in the waters of the Arctic shelf, consisting of a solid body, geophone, tools, registration and storage of information, distinguish fact that additionally, the station has rugged streamlined, energy-power installation, propeller, gyroscope, measuring path, depth sounder, depth sensor, locator signals sonar beacon, means to control buoyancy and the on-Board computer control device to move the station from one point of the sea to another, hang, descent to the bottom, rise from the bottom to the specified depth and at the surface of the sea.



 

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