CN109765620B - Near-bottom towing type random receiving cable seismic data acquisition system and method - Google Patents
Near-bottom towing type random receiving cable seismic data acquisition system and method Download PDFInfo
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Abstract
The invention discloses a near-bottom towing type random receiving cable seismic data acquisition system and a near-bottom towing type random receiving cable seismic data acquisition method, wherein the system comprises a laboratory console, a towing frame and a towing cable; the acquisition method comprises 5 steps of system configuration, system layout, data acquisition, system recovery, data processing and the like. The invention adopts the technical proposal that hydrophones on receiving channels are arranged at random positions, and has the functions of reducing effective channel spacing, improving transverse resolution and efficiently collecting; the combination and expansion of the system are conveniently and flexibly completed by adopting the combination and connection design of a plurality of subsections, and the system has stronger adaptability to the observation target.
Description
Technical Field
The invention relates to the field of marine geophysical exploration, in particular to a near-bottom towing type random receiving cable seismic data acquisition system and method.
Background
Marine geology and mineral resource surveys are fundamental and strategic surveys activities in which seismic methods play an important role in subsea construction and mineral resource surveys. The conventional sea surface towing earthquake has the problems of long distance from the sea bottom, low data signal-to-noise ratio and insufficient transverse resolution, and is generally difficult to apply to high-resolution earthquake investigation (such as natural gas hydrate, sulfide and other resource investigation).
In recent years, various near-bottom towing type seismic acquisition systems are developed at home and abroad, such as DTAGS of American navy research laboratory, SYSIF of French ocean development institute and the like, and play an important role in high-resolution seismic exploration. The system has the greatest characteristics that the receiving cable is arranged at the position close to the sea bottom to receive the seismic signals, so that the radius of the first Fresnel zone is greatly reduced, and the transverse resolution of the seismic data is improved. Especially when the device is matched with a deep towing source (such as a Helmholtz resonator sound source, 200-1000 Hz), the detection effect is better.
The deep sea towing has higher requirements on the pressure resistance and the overall operation mode of the seismic cable, and the deep sea hydrophone (particularly for the operation depth of 3000-6000 m) has high technical requirements, large demand and high cost, so that the cable is quite expensive in manufacturing cost and high in seismic operation cost. In view of the great difficulty of near-sea towing cable operations, it is an important challenge in current deep sea towing seismic equipment how to reduce the development costs of the deep sea towing cables (i.e. to use a certain number of hydrophones to increase the cable length as much as possible), to increase the data receiving capacity (i.e. to further increase the resolution of the data on the premise of a certain cable length) and to operate flexibility (i.e. to adjust the cable towing position for different targets).
From this, the near-bottom towed seismic acquisition system is an important and promising seismic data acquisition scheme. How to reduce the equipment and operation cost and improve the operation flexibility is an important technical problem to be solved at the present stage of the method.
Disclosure of Invention
In order to overcome the shortcomings in the prior art, the invention provides a near-bottom towed random receiving cable seismic data acquisition system and method.
To achieve the above object, in one aspect, the present invention provides a near-bottom towed random-reception cable seismic data acquisition system, which is composed of a laboratory console, a towing frame, and a towing cable;
the laboratory console comprises an acquisition controller, an acquisition workstation, a navigation module and an uninterruptible power supply. The acquisition controller is connected with an acquisition control bin in the towing frame through a photoelectric composite cable and mainly completes signal acquisition and arrangement, photoelectric signal conversion, signal interpretation and control; the acquisition workstation is used for system parameter setting, data display and data storage, and is connected with a high-precision navigation signal through the navigation module and transmitted to the underwater acquisition control bin through the acquisition controller; uninterruptible power supplies provide stable power access services for other devices.
The towing frame provides various signal conversion and control functions for an intermediate link connecting a laboratory with a receiving cable; the system comprises a power supply module, an underwater control cabin, an ultra-short baseline acoustic beacon, an attitude instrument and a depth gauge module. The power module provides the power required for towing the cable. The underwater control cabin comprises a power amplifier module, an acquisition control module and a propulsion control module; the power amplifier realizes the amplifying function of a transmission signal; the acquisition control module is connected with the towing cable and used for providing data transmission and control of the depth adjusting module; the propulsion control module is connected with the depth gauge, the attitude meter and the propeller, and controls the rotation of the propeller according to the obtained data of the attitude and the depth gauge, so that the position control in the towing direction is realized, and the control of the relative positions of the seismic source and the cable is further realized. The ultra-short baseline beacon receives signals from the acquisition ship acoustic array and provides a high-precision acoustic positioning function of the underwater towed frame.
The towing cable comprises a leading section, a front shock absorption section, a working section, a rear shock absorption section, a depth setting controller and a tail mark. The leading section is used for controlling the distance between the cable and the towing frame; the front shock absorption section is internally provided with a shock absorption device for isolating shock interference signals from the towing frame; the working section comprises a hydrophone and a pressure sensor and is used for receiving vibration and pressure signals; the rear shock absorption section is internally provided with a shock absorption device which is used for isolating shock interference signals from the tail mark; the depth controller is a part of the cable, the interface can be connected with the receiving section and is connected with a laboratory console, and the sinking and floating of the cable are realized by controlling the attack angle to generate lifting force and descending force; the tail marks are used for straightening the cable. The cable housing is a PU pipe made of polyurethane materials, the interior of the cable housing is filled with silicone oil, the connecting circuit is placed in the silicone oil without being stressed, and the cable is stressed through a Kevlar rope.
In the trailing cable, the hydrophones are distributed at random positions and are arranged at a part of positions selected by adopting a segmented random sampling strategy on the basis of regular dense distribution. The segmented random sampling has the spectral characteristic of blue noise, and is beneficial to subsequent reconstruction processing. The number of the hydrophones is set to be N, the number of the dense equidistant grid points is set to be N (in general, N is more than or equal to 2N), namely the hydrophones are randomly distributed on N random positions in the N equidistant positions. The hydrophone arrangement scheme is as follows:
1) The N points are divided into N segments. When N is an integer multiple of N, it can be equally divided, with each part having int (N/N) points. When N is not an integer multiple of N, N remains after halving r N-int (N/N) ×n points, where int () is a rounding operation.
2) Of the n parts, n is randomly selected r Segments; then the rest n r Put selected n into each point r In the individual sections.
3) Randomly extracting a point from the n sections processed in the step 2) to serve as the installation position of the hydrophone.
According to the scheme, the mounting positions of the hydrophones can be set according to the actual conditions and in any proportion, so that the hydrophone is a uniform and random scheme, and the problem that the continuous large-area position of the hydrophone is lost in a large range and the difficulty is brought to data reconstruction is avoided.
As a further improvement of the invention, in the laboratory console, the collecting work station can see the height of the towing frame from the seabed and the underwater position and posture of the cable in real time, so that the operation mode can be conveniently adjusted in real time, and the towing operation safety and the data quality are ensured.
As a further development of the invention, in the trailing cable, a pressure sensor is mounted in the central position of each receiving section and the measurement data are transmitted in real time to the laboratory console by means of a control module.
On the other hand, the invention provides a near-bottom towed random receiving cable seismic data acquisition method, which comprises the following steps:
step 1: and (5) configuring a system. High-precision topographic information of the working area needs to be collected before laying, and the working position cannot be changedTo exceed the maximum operating water depth of the system. According to the exploration targets, the length, the towing depth and the towing angle of the cable are determined, further the counterweight of the towing frame is determined, and the system is ensured to stably tow at a certain depth according to a certain offset distance. The distance between the towing frame and the seabed is larger than the length of the cable, so that the cable is prevented from bottoming. Let x be s Is the horizontal distance x between the vibration source and the stern o For offset distance, the cable laying length of the photoelectric composite cable is L, the towing angle is alpha, and the distance from the first hydrophone to the stress point of the towing frame is x d The configuration of the system satisfies the following relationship:
it can be seen that when x s And x d When the device is fixed, the size of the offset distance can be controlled by adjusting and dragging the angle alpha, the cable laying length L is controlled by a winch, and the dragging angle alpha is controlled by a propelling device of the dragging frame.
Step 2: and (5) system layout. The cable is wound on the winch, the winch rotates to send out the cable when the cable is laid, the cable is laid in the sea according to the sequence of the tail mark, the rear shock absorption section, the working section, the front shock absorption section and the front guide section, and finally, the towing frame is pulled up by using the winch and the optical cable to be laid in the sea. Continuing to pay off the cable, and testing whether the system works normally when the cable reaches 100 m;
step 3: and (5) data acquisition. And when the cable reaches the working depth, releasing the ultra-short baseline array, opening the ultra-short baseline, and collecting the position data of the towing frame. And the propulsion module controlling the towing frame controls the propeller to rotate, keeps the system stably towed, and records information of the towing frame, the position and the state for subsequent data processing. Carrying out seismic data acquisition operation by matching with other equipment (systems such as a seismic source, navigation, gun control and the like); controlling the sinking depth of the cable by a depth setting controller, and monitoring in real time by pressure information;
step 4: and (5) recycling the system. The ultrashort baseline is first closed and the ultrashort baseline matrix is recovered. And closing the propulsion control module of the towing frame. The acquisition system is closed, the towing frame and cable are retracted, and the cable is towed and stored using a winch.
Step 5: and (5) reconstructing data. The step reconstructs the collected random arrangement data into regular grid data, thereby meeting the requirement of conventional data processing.
The working frequency band of the ultra-short base line and the working frequency band of the seismic acquisition data are greatly different, so that the quality of the data is not affected. But the acquired data are distributed on random receiving positions, reconstruction processing is carried out by using a reconstruction method based on compressed sensing, so that data on a regular grid are obtained, and a foundation is laid for subsequent data processing.
The sampling process of seismic data can be expressed as:
b＝Rf, (8)
wherein,is sampling seismic data, +.>Is a sampling matrix (N < N.ltoreq.2n),>regular seismic data.
Using Curvelet transform as a sparse transform for seismic data, f has sparsity in the sparse transform domain S, then (2) can be translated into:
b＝Ax with A:＝RS * , (9)
wherein, represents conjugation.The coefficients in S that are f (only k non-zero values) are sparse representations of f.
Mathematically it has been demonstrated that (3) can still be solved, provided that the constrained equidistant characteristics satisfy a random theory, indicating that this can be achieved when R is a gaussian random matrix with independent uniformity distribution. At this time, the following problem needs to be solved:
wherein, |x| 0 :＝#{x,x i Not 0 }. Is x 0 Norms, x i The ith term of x. Using Lagrangian multiplier method to rewrite constrained problem (4) to unconstrained problem:
here the number of the elements is the number,is an estimate of x.
We solve (5) using an iterative thresholding method, the scheme is as follows:
wherein i is an iteration index, θ is a threshold, gradually decreases with the number of iterations,ensuring the stability and convergence speed of the iterative algorithm for step length, < ->Is a threshold algorithm.
Iterating to a threshold value below 10 of the sparse domain maximum -5 Stopping iteration to obtain a solving resultThereby obtaining the final data reconstruction result +.>
As a further improvement of the present invention, in step 1, a suitable inter-element reference track pitch (referred to as a track pitch applied to a cable of a regular equal-interval distribution) is selected on the basis of the preliminary acquisition of the existing data of the detection target size and range.
As a further development of the invention, in step 1, the tail mark has the function of the towing depth, and the sinking depth of the cable can be controlled under the condition of towing at a certain speed.
As a further improvement of the invention, in the step 5, the data reconstruction processing preferably selects curvelet transformation as sparse transformation of the seismic data, and adopts an accelerated iteration threshold method to solve the problem, thereby finally completing the high-precision reconstruction processing.
The beneficial effects of the invention are as follows:
(1) The deep sea near-bottom towing cable arranges the hydrophones on the receiving channels at random positions, and a certain number of hydrophones can be used for developing longer cables, so that the observation range is increased, and the detection cost is reduced. The purpose of reducing the effective track spacing is achieved by reconstructing the data at the missing position through the data, and the transverse resolution is improved;
(2) The propulsion control module of the towing frame can adjust the towing position (depth, offset distance and the like) and the towing state of the towing frame and the cable according to the requirement; the receiving cable adopts a design of combining and connecting a plurality of subsections, and the length of the cable can be flexibly adjusted according to the reflection angles of different detection targets. Therefore, the invention has stronger adaptability to detection targets with different dip angles and sizes;
(3) Has better function expansion capability. A deep sea towing seismic source can be installed in the towing frame, and the purpose of improving the transverse resolution and the longitudinal resolution is further achieved by matching the deep sea towing seismic source with the system; other types of sensors can be conveniently hung, and the multi-parameter data observation function can be efficiently and economically realized.
Drawings
FIG. 1 is a schematic diagram of the overall composition of a near-bottom towed random receive cable seismic data acquisition system of the present invention;
FIG. 2 is a schematic diagram of the laboratory console of FIG. 1;
FIG. 3 is a schematic view of the trailing frame structure of FIG. 1;
FIG. 4 is a schematic view of the trailing cable of FIG. 1;
FIG. 5 is a schematic diagram of the received reflected wave paths of the cable at different locations;
FIG. 6 is a schematic diagram of a hydrophone arrangement in the trailing cable of FIG. 1;
FIG. 7 is a schematic diagram of the trailing cable of FIG. 1 in comparison to a conventional cable;
FIG. 8 is a schematic diagram of the system geometry during towing operations in accordance with the present invention;
FIG. 9 shows the data collected by the invention and the reconstruction result thereof, wherein the track spacing is 25m, the number of hydrophones is 16, and the reconstruction obtains 32-track regular data.
Detailed Description
As shown in FIG. 1, the present invention provides a near-bottom towed random receive cable seismic data acquisition system and method.
In a first aspect of the invention, a near-bottom towed random receive cable seismic data acquisition system is provided, the system consisting of a laboratory console 1, a towing frame 2, and a towing cable 3. Other auxiliary equipment comprises an A-shaped frame, a photoelectric composite cable and a shipborne seismic source system, and the auxiliary equipment is matched with the system in the data acquisition process.
As shown in fig. 2, the laboratory console 1 includes an uninterruptible power supply 11, an acquisition workstation 12, an acquisition controller 13, an ultra-short baseline workstation 14, and an onboard acoustic array 15. The uninterrupted power supply is connected with ship electricity to provide stable power supply access service for other equipment. The acquisition workstation 12 is used for system parameter setting, data display and data storage, and is used for navigation control by accessing on-board high-precision GPS signals; the depth of the towing frame 2 and the underwater position and posture of the towing cable 3 can be seen in real time, so that the operation mode can be adjusted in real time, and the towing operation safety and the data quality are ensured.
The acquisition controller 13 is connected with the towing frame 2 through a photoelectric composite cable and mainly completes collection and arrangement of optical cable signals and terminal signals, photoelectric signal conversion, signal interpretation and control.
As shown in fig. 3, the towing frame 2 provides various functions such as signal conversion and control for an intermediate link connecting the laboratory console 1 and the receiving cable 3; comprises a power supply module 21, an underwater control cabin 22, an attitude instrument 23, a depth gauge 24, a propeller 25 and an ultra-short baseline beacon 26. The power module 21 provides the power required to tow the cable. The underwater control cabin 22 comprises a power amplification module 221, an acquisition control module 222 and a propulsion control module 223; wherein, the power amplification module 221 realizes the amplification function of the transmission signal; the acquisition control module 222 is connected with the trailing cable and provides data transmission and control of the depth adjustment module; the propulsion control module 223 is connected with the attitude instrument 23, the depth gauge 24 and the propeller 25, the obtained attitude and depth data are transmitted to the laboratory console 1 in real time, and the rotation of the propeller 25 is controlled according to the data, so that the position control in the towing direction is realized, and the control of the relative positions of the seismic source and the cable is further realized. The ultra-short baseline beacons 26 receive signals from the acquisition ship acoustic array and provide high accuracy acoustic positioning of the underwater towed frame 2.
As shown in fig. 4, the trailing cable 3 includes a leading section 31, a front shock absorbing section 32, a working section 33, a rear shock absorbing section 34, a depth controller 35, and a tail 36. The leading section 31 is used for controlling the distance between the trailing cable 3 and the trailing frame 2; the front shock absorbing section 32 is internally provided with a shock absorbing device for isolating shock interference signals from the towing frame; the working section 33 contains hydrophones and pressure sensors for receiving vibration and pressure signals; the rear shock absorption section 34 is internally provided with a shock absorption device for isolating shock interference signals from the tail mark; the depth controller 35 is a part of a cable, an interface can be connected with the receiving section and is connected with a laboratory console, and the sinking and floating of the cable are realized by controlling the attack angle to generate lifting force and descending force; the tail 36 is used to straighten the cable. The cable housing is a PU pipe made of polyurethane materials, the interior of the cable housing is filled with silicone oil, the connecting circuit is placed in the silicone oil without being stressed, and the cable is stressed through a Kevlar rope. And determining that the reference track distance of the cable is 5m according to the scale of the exploration target.
As shown in fig. 5, which illustrates a schematic view of the propagation path of the seismic wavefield from the source after reflection by the target geologic volume; under the condition of determining the position of a seismic source, hydrophone signals with large offset and large depth reflect large dip angle construction information, and hydrophone signals with small offset and small depth reflect gentle construction information. Therefore, the variable offset has great significance for detecting complex geological structures with different dip angles. The towing cable can be stably towed in deep sea with a certain depth at a position with a certain offset distance through the integrated control of the photoelectric composite cable release length, the propulsion control module 223 and the depth setting controller 35.
As shown in fig. 6, in the trailing cable 3, the hydrophones 331 are distributed at random locations and are mounted at a portion of locations selected using a piecewise random sampling strategy on a regularly densely distributed basis. The segmented random sampling has the spectral characteristic of blue noise, and is beneficial to subsequent reconstruction processing. The method is divided into two cases, 1) the dense equally-spaced grid points are integer multiples of the number of hydrophones, 61 is the distribution of the conventional cable hydrophones, and each segment is firstly segmented into 2 points; a position is randomly selected from each segment as the hydrophone position, resulting in the final design. 2) The dense equidistant grid points are not integral multiples of the number of the hydrophones, 63 is the distribution of the conventional cable hydrophones, and is segmented firstly, each segment has 2 points, and the rest has 1 point; then randomly adjusting the point into a certain segment; the final design is obtained by randomly selecting a position from each segment as the hydrophone position, 64.
As shown in fig. 7, 71 is a conventional cable receiving trace distribution with a trace pitch of 5m;72 is a random distribution of receive channels, the reference channel spacing is 5m,73 is a distribution of receive channels after reconstruction, and the channel spacing is 5m. As can be seen from the comparison of 71 and 73, the length of the cable can be effectively expanded under the condition of not reducing the track spacing, and the cable is used for large offset exploration. 74 is a conventional cable receiving trace distribution with a trace pitch of 10m;75 is a random distribution of receive channels, the reference channel spacing is 5m,76 is a distribution of receive channels after reconstruction, and the channel spacing is 5m. As can be seen by comparing 74 and 76, the present invention allows for reduced trace spacing while maintaining the cable length for high resolution seismic exploration.
The installation position of the hydrophone 331 can be set according to the actual situation by the scheme, so that the scheme is a uniform and random scheme, and the problem that the continuous large-area hydrophone position is lost in a large range to cause difficulty in data reconstruction is avoided. In the trailing cable 3, there are also pressure sensors 332 distributed in the central position of each working section and transmit the measurement data in real time to the laboratory console 1 by means of a control module.
On the other hand, the invention provides a near-bottom towed random receiving cable seismic data acquisition method, which comprises the following steps:
step 1: and (5) configuring a system. High-precision topographic information of the operation area needs to be collected before deployment, and the operation position cannot exceed the maximum working water depth of the system. According to the exploration targets, the length, the towing depth and the towing angle of the cable are determined, further the counterweight of the towing frame is determined, and the system is ensured to stably tow at a certain depth according to a certain speed. The distance between the towing frame and the seabed is larger than the length of the cable, so that the cable is prevented from bottoming;
as shown in fig. 8, the configuration of the system satisfies the following relation:
horizontal distance x of the source from stern s At 30m, the offset is set to 350m, and the distance from the first hydrophone to the stress point of the towing frame is x d When the towing operation is required to be performed at the water depth of 2000m, the cable laying length of the photoelectric composite cable is 2027m, and the towing angle is 9.37 degrees.
Step 2: and (5) system layout. The cable is wound on the winch, the winch rotates to send out the cable when the cable is laid, the cable is laid in the sea according to the sequence of the tail mark, the rear shock absorption section, the working section, the front shock absorption section and the front guide section, and finally, the towing frame is pulled up by using the winch and the optical cable to be laid in the sea. Continuing to pay off the cable, and testing whether the system works normally when the cable reaches 100 m;
step 3: and (5) data acquisition. And when the cable reaches the working depth, releasing the ultra-short baseline array, opening the ultra-short baseline, and collecting the position data of the towing frame. And the propulsion module controlling the towing frame controls the propeller to rotate, keeps the system stably towed, and records information of the towing frame, the position and the state for subsequent data processing. Carrying out seismic data acquisition operation by matching with other equipment (systems such as a seismic source, navigation, gun control and the like); controlling the sinking depth of the cable by a depth setting controller, and monitoring in real time by collecting pressure information displayed by an interface;
step 4: and (5) recycling the system. The ultrashort baseline is first closed and the ultrashort baseline matrix is recovered. The pusher of the trailing frame is closed. The acquisition system is closed, the towing frame and cable are retracted, and the cable is towed and stored using a winch.
Step 5: and (5) reconstructing data. The step reconstructs the collected random arrangement data into regular grid data, thereby meeting the requirement of conventional data processing.
As shown in fig. 9, 91 is data collected by a random cable, and the 16-track and reference track pitch is 10m. During data reconstruction processing, curvelet transformation is selected as sparse transformation of seismic data, and an acceleration iteration threshold method is adopted to solve problems, so that high-precision reconstruction processing is finally completed. 92 is reconstructed seismic data with 32 traces and a trace spacing of 10m. It can be seen that the invention utilizes fewer hydrophones to realize the effect of arranging cables at regular intervals, and reduces the exploration cost.
Claims (2)
1. A near-bottom towed random receiving cable seismic data acquisition method is realized based on a near-bottom towed random receiving cable seismic data acquisition system, and the system comprises a laboratory console, a towing frame and a towing cable; the laboratory console is connected with the towing frame through a photoelectric composite cable; the towing frame is connected with the towing cable;
the laboratory console comprises an acquisition controller, an acquisition workstation, a navigation module and an uninterruptible power supply; the acquisition controller is connected with an acquisition control bin in the towing frame through a photoelectric composite cable; the acquisition workstation is used for system parameter setting, data display and data storage, and is connected with a high-precision navigation signal through the navigation module and transmitted to the underwater acquisition control bin through the acquisition controller; the uninterrupted power supply provides power;
the towing frame comprises an underwater control cabin, and the underwater control cabin comprises a power amplifier module, an acquisition control module and a propulsion control module; the power amplifier realizes the amplifying function of a transmission signal; the acquisition control module is connected with the towing cable and used for providing data transmission and control of the depth adjusting module; the propulsion control module is connected with the depth gauge, the attitude meter and the propeller, and controls the rotation of the propeller according to the obtained data of the attitude and the depth gauge, so that the position control in the towing direction is realized, and the control of the relative positions of the seismic source and the cable is further realized;
the towing frame further comprises a power supply module, an ultra-short baseline acoustic beacon, an attitude instrument, a propeller and a depth gauge; the power module provides a power supply required by towing a cable, and the ultra-short baseline acoustic beacon receives signals from the acoustic array of the acquisition ship and provides high-precision acoustic positioning of the underwater towing frame;
the towing cable comprises a leading section, a front shock absorption section, a working section, a rear shock absorption section, a depth setting controller and a tail mark which are connected in sequence; the front shock absorption section is used for isolating shock interference signals from the towing frame; the working section comprises a hydrophone and a pressure sensor and is used for receiving vibration and pressure signals; the rear shock absorption section is used for isolating vibration interference signals from the tail marks; the depth setting controller is used for realizing sinking and floating of the cable; the tail mark is used for straightening the trailing cable,
in the trailing cable, the number of hydrophones is set to be N, the number of dense equidistant grid points is set to be N, the hydrophones are randomly distributed on N random positions in the N equidistant grid positions, and the hydrophone arrangement scheme is as follows:
1) Dividing N points into N sections; when N is an integer multiple of N, the segments can be equally divided, and each segment has int (N/N) points; when N is not an integer multiple of N, N remains after halving r N-int (N/N) ×n points, where int () is a rounding operation;
2) Of the n segments, n is randomly selected r Segments; then the rest n r The individual points being randomly assigned to the selected n r In each segment;
3) Randomly extracting a point location from the n sections processed in the step 2) to serve as the installation position of the hydrophone;
the towing cable shell is a PU pipe made of polyurethane materials, the inside of the towing cable shell is filled with silicone oil, the inner connecting line of the towing cable is placed in the silicone oil and is not stressed, and the towing cable is stressed through a Kevlar rope;
in the towing cable, a pressure sensor is arranged at the central position of each receiving section, and measurement data are transmitted to a laboratory console in real time through a control module;
the method is characterized by comprising the following steps:
step 1: system configuration
According to the exploration target, determining the length, the towing depth and the towing angle of the cable, further determining the counterweight of the towing frame, and ensuring that the system stably tows at a certain depth according to a certain offset distance;
let x be s Is the horizontal distance x between the vibration source and the stern o For offset distance, the cable laying length of the photoelectric composite cable is L, the towing angle is alpha, and the distance from the first hydrophone to the stress point of the towing frame is x d The configuration of the system satisfies the following relationship:
step 2: system deployment
When the cable is laid, the winch rotates to send the cable out, the cable is laid in the sea according to the sequence of the tail mark, the rear shock absorption section, the working section, the front shock absorption section and the front guide section, and finally, the winch and the optical cable are used for pulling up the towing frame to be laid in the sea; continuing to pay off the cable, and testing whether the system works normally when the depth is set;
step 3: data acquisition
When the cable reaches the working depth, releasing the ultra-short baseline array, opening the ultra-short baseline, collecting the position data of the dragging frame, controlling the propelling module of the dragging frame to control the propeller to rotate, keeping the system stably dragged, and recording the dragging frame, the position and the state information for subsequent data processing; performing seismic data acquisition operation; controlling the sinking depth of the cable by a depth setting controller, and monitoring in real time by pressure information;
step 4: system recovery
Firstly, closing an ultrashort baseline, and recovering the ultrashort baseline matrix; closing the propulsion control module of the towing frame; closing the acquisition system, recovering the towing frame and the cable, and towing and storing the cable by using a winch;
step 5: data reconstruction
And reconstructing the collected random arrangement data into regular grid data by using a reconstruction method based on compressed sensing, thereby meeting the requirements of conventional data processing.
2. The near-bottom towed random receive cable seismic data acquisition method of claim 1, wherein said step 5 is specifically:
the sampling process of the seismic data is expressed as:
b＝Rf, (2)
wherein,is sampling seismic data, +.>Is a sampling matrix, N is less than or equal to 2N, < ->Is regular seismic data;
using Curvelet transform as a sparse transform for seismic data, f has sparsity in the sparse transform domain S, then (2) can be translated into:
b＝Ax with A:＝RS * , (3)
wherein, represents the conjugation,the coefficient in S for f is a sparse representation of f;
when R is a gaussian random matrix with independent consistency distribution, equation (3) can be solved, where the following problem needs to be solved:
wherein, |x| 0 :＝#{x,x i Not 0 }. Is x 0 Norms, x i For the ith term of x, the constrained problem (3) is rewritten as an unconstrained problem using the lagrangian multiplier:
here the number of the elements is the number,an estimate of x;
solving the step (5) by using an iterative threshold method, wherein the scheme is as follows:
where i is an iteration index, θ is a threshold,for step size->Is a threshold algorithm;
iterating to a threshold value below 10 of the sparse domain maximum -5 Stopping iteration to obtain a solving resultThereby obtaining the final data reconstruction result +.>
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4958331A (en) * | 1974-02-25 | 1990-09-18 | The United States Of America As Represented By The Secretary Of The Navy | Towed sonar receiving array |
| WO2012041844A1 (en) * | 2010-09-28 | 2012-04-05 | Shell Internationale Research Maatschappij B.V. | Marine seismic surveying assembly and method |
| CN103680727A (en) * | 2013-12-05 | 2014-03-26 | 天津市远海声学仪器有限公司 | Towed damping cable for marine seismic prospecting |
| CN104570123A (en) * | 2014-12-31 | 2015-04-29 | 中国石油天然气集团公司 | Offshore exploration trajectory determining method and device |
| CN105510977A (en) * | 2015-12-31 | 2016-04-20 | 中国海洋大学 | Pull-type marine seismic prospecting vertical cable data acquisition system |
| RU2607076C1 (en) * | 2015-09-29 | 2017-01-10 | Федеральное государственное бюджетное научное учреждение "Федеральный исследовательский центр Институт прикладной физики Российской академии наук" (ИПФ РАН) | Method of controlling seismoacoustic towed streamers and positioning device for its implementation |
| CN209433023U (en) * | 2019-02-20 | 2019-09-24 | 自然资源部第二海洋研究所 | A kind of nearly bottom pull-type receives cable system for acquiring seismic data at random |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7660191B2 (en) * | 2005-07-12 | 2010-02-09 | Westerngeco L.L.C. | Methods and apparatus for acquisition of marine seismic data |
| US7835224B2 (en) * | 2008-03-31 | 2010-11-16 | Westerngeco L.L.C. | Reconstructing low frequency data recordings using a spread of shallow and deep streamers |
| US10001575B2 (en) * | 2010-06-29 | 2018-06-19 | Pgs Geophysical As | Seismic data acquisition system with selectively enabled sensor units, and associated methods |
| US9733375B2 (en) * | 2011-03-01 | 2017-08-15 | CGGVeritas Services (U.S.) Inc. | Method and device for alternating depths marine seismic acquisition |
| US20140121977A1 (en) * | 2012-11-01 | 2014-05-01 | Pgs Geophysical As | Methods and systems for monitoring a petroleum reservoir |
| CN110770608B (en) * | 2017-03-29 | 2023-01-24 | 斯伦贝谢技术有限公司 | Compressive sensing imaging |
-
2019
- 2019-02-20 CN CN201910126978.5A patent/CN109765620B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4958331A (en) * | 1974-02-25 | 1990-09-18 | The United States Of America As Represented By The Secretary Of The Navy | Towed sonar receiving array |
| WO2012041844A1 (en) * | 2010-09-28 | 2012-04-05 | Shell Internationale Research Maatschappij B.V. | Marine seismic surveying assembly and method |
| CN103680727A (en) * | 2013-12-05 | 2014-03-26 | 天津市远海声学仪器有限公司 | Towed damping cable for marine seismic prospecting |
| CN104570123A (en) * | 2014-12-31 | 2015-04-29 | 中国石油天然气集团公司 | Offshore exploration trajectory determining method and device |
| RU2607076C1 (en) * | 2015-09-29 | 2017-01-10 | Федеральное государственное бюджетное научное учреждение "Федеральный исследовательский центр Институт прикладной физики Российской академии наук" (ИПФ РАН) | Method of controlling seismoacoustic towed streamers and positioning device for its implementation |
| CN105510977A (en) * | 2015-12-31 | 2016-04-20 | 中国海洋大学 | Pull-type marine seismic prospecting vertical cable data acquisition system |
| CN209433023U (en) * | 2019-02-20 | 2019-09-24 | 自然资源部第二海洋研究所 | A kind of nearly bottom pull-type receives cable system for acquiring seismic data at random |
Non-Patent Citations (2)
| Title |
|---|
| Forward and inverse problems in towed cable hydrodynamics;Polydorides, N;OCEAN ENGINEERING;全文 * |
| 海洋地震拖缆姿态动态仿真研究;吴喆莹;中国优秀硕士论文辑;全文 * |
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