Intelligent tracking and monitoring method for marine sediment plume migration process

Abstract

The present invention relates to the technical field of seabed sediment monitoring, and in particular to an intelligent tracking and monitoring method for the migration process of marine sediment plumes. The method comprises the following steps: S1, placing a device for monitoring sediment plumes at a designated position in the ocean; S2, monitoring the plume concentration, obtaining the sediment concentration in the cylindrical area, and moving the monitoring device to the position of the highest sediment concentration; S3, after the monitoring device is moved into place, repeating step S2, the monitoring device moves toward the area with a narrower range of upper and lower cross-sections of the plume and a higher plume concentration, until the source of the sediment plume is found; S4, after finding the source of the sediment plume, driving the device to move from the source along the midline of the sediment plume diffusion to monitor the diffusion process of the sediment plume. It can track the source of the sediment plume and track the diffusion process of the monitoring plume, thus realizing the monitoring and tracing of the sediment plume.

Description

Technical Field

[0001] The invention relates to the technical field of seabed sediment monitoring, and in particular to an intelligent tracking and monitoring method for a marine sediment plume migration process. Background Art

[0002] Sediment plumes are a special flow structure formed in water bodies due to the diffusion of bottom sediments and the transport of suspended matter. There are many factors that induce sediment plumes, including natural factors such as submarine landslides, submarine earthquakes, volcanic activities, tidal effects, etc., as well as human factors such as deep-sea mining, submarine construction, dredging activities, etc.

[0003] Sediment plumes are usually high in concentration, long in duration, and have a wide range of propagation. A key issue in the study of sediment plumes is to explore the impact of sediment plumes on deep-sea benthic organisms. Sediment plumes will increase the concentration of suspended particles, aggravate the degree of light attenuation, and hinder the growth of phytoplankton in the light zone, which will cause the concentration of dissolved oxygen in the ocean's euphotic layer to decrease, thus causing serious impacts on marine life and the ecological environment. In addition, particulate matter and metal substances in sediment plumes can clog the respiratory system of organisms, damage digestive organs, and directly affect marine life. Once a sediment plume is generated, it will cause long-term and irreparable damage to a large area of ​​the marine environment in the sea area.

[0004] The process of sediment plume tracing is the premise of sediment plume research. On the one hand, determining the source of the plume can help take timely measures to reduce the negative impact on the marine ecosystem and protect marine biodiversity; on the other hand, if the sediment plume is caused by natural disasters such as submarine landslides or earthquakes, tracing the source can help assess the risk of further geological disasters, thereby conducting effective disaster warning and mitigation; in addition, tracing the source of sediment plumes can also help discover marine mineral resources. For example, metal sulfide deposits are usually present in submarine hydrothermal vents, and tracing the sediment plumes of hydrothermal vents can help discover mineral resources. Therefore, developing effective sediment plume tracing technology to identify and track the source of sediment plumes is of great significance for protecting marine ecosystems, ensuring the rational development and utilization of marine resources, and preventing and reducing the impact of natural disasters.

[0005] For sediment plume research, on the one hand, there is a lack of research on the spatial and temporal disturbance of sediment plumes; on the other hand, the sediment plume transport process is complex and there is considerable uncertainty, which makes the study of sediment plumes extremely challenging. At present, the monitoring and tracing methods for sediment plumes have not been fully established. Summary of the invention

[0006] The purpose of the present invention is to overcome the above-mentioned defects of the prior art and propose an intelligent tracking and monitoring method for the migration process of marine sediment plumes, which can track the source of the sediment plume and track and monitor the diffusion process of the plume, thereby realizing the monitoring and tracing of the sediment plume.

[0007] The technical solution of the present invention is: an intelligent tracking and monitoring method for the migration process of marine sediment plume, which includes the following steps:

[0008] S1. placing a device for monitoring sediment plumes at a designated location in the ocean, recording the location and water depth information of the device, and measuring the interface location information of the sediment plumes;

[0009] S2. Monitor the plume concentration to obtain the sediment concentration in the cylindrical area, analyze the sediment concentration data to obtain the position of the highest sediment concentration, and move the monitoring equipment to the position of the highest sediment concentration;

[0010] S3, after the monitoring device is moved to the position, step S2 is repeated to find the position of the next maximum sediment concentration again, and the monitoring device is moved again to the position of the maximum sediment concentration obtained in this step;

[0011] Repeat the above operation, and move the monitoring equipment toward the area with narrower upper and lower cross-sections of the plume and higher plume concentration until the source of the sediment plume is found;

[0012] S4. After finding the source of the sediment plume, drive the device to move along the center line of the sediment plume diffusion from the source to monitor the diffusion process of the sediment plume.

[0013] In the present invention, the sediment plume monitoring device comprises:

[0014] The buoy mechanism is connected to the running mechanism below it through a cable, and a first multi-beam echo sounder with an opening downward is fixed on the bottom surface of the buoy mechanism;

[0015] A walking mechanism, a top surface of which is fixed with a third pressure sensor and a second multi-beam echo sounder;

[0016] The weight and float are located at the center of the device;

[0017] Monitoring mechanisms are respectively arranged on the cables between the buoy mechanism and the weight, and on the cables between the floating body and the walking mechanism bracket, and the monitoring mechanisms move up and down and rotate along the cables.

[0018] Monitoring agencies include:

[0019] The upper and lower moving parts include an upper cylindrical silo and a lower sealed silo. The cylindrical silo is open and an annular oil bag is arranged inside the cylindrical silo. The sealed silo is provided with a hydraulic drive component, a control component, a motor and a power supply. The hydraulic drive component is connected to the annular oil bag through an oil pipe.

[0020] The rotating part includes a rotating disc and a bearing located in the middle of the rotating disc, the rotating disc is rotatably connected to the bearing, a ring gear is fixed at the center of the top surface of the rotating disc, the ring gear and the pinion gear on the outside thereof are meshed with each other, the pinion gear is drivingly connected to the output shaft of the motor, and a pressure sensor, a turbidity meter, an angle sensor and an acoustic Doppler flow profiler are arranged on the top surface of the rotating disc;

[0021] Connecting rod, the bottom of the sealed chamber is fixedly connected to the bearing through the connecting rod, and the cable passes through the upper and lower moving parts, the connecting rod and the rotating part in sequence;

[0022] The monitoring mechanism between the buoy mechanism and the weight is the first monitoring mechanism, and the pressure sensor in the first monitoring mechanism is the first pressure sensor; the monitoring mechanism between the floating body and the walking mechanism is the second monitoring mechanism, and the pressure sensor in the second monitoring mechanism is the second pressure sensor.

[0023] In step S1, a three-dimensional coordinate system is established with the location of the buoy mechanism as the origin. The location coordinates of the monitoring device are (x0, y0). The first pressure sensor in the first monitoring mechanism, the second pressure sensor in the second monitoring mechanism, and the third pressure sensor on the walking mechanism respectively sense and record the current location P 01 , P 02 , P 03 , thus obtaining the seawater depth h0 and the depth h of the first monitoring mechanism 01 , and the depth h of the second monitoring mechanism 02 :

[0024] ,

[0025] ,

[0026] ;

[0027] The upper interface position information of the sediment plume is measured by the first multi-beam echo sounder, and the detected interface position information of the sediment plume is sent to the control component of the first monitoring mechanism; the lower interface position information of the sediment plume is measured by the second multi-beam echo sounder, and the detected interface position information of the sediment plume is sent to the control component of the second monitoring mechanism; the distance L between the first multi-beam echo sounder of the buoy mechanism and the upper interface of the sediment plume is 01 for:

[0028] ,

[0029] The distance L between the second multi-beam echo sounder of the walking mechanism and the lower interface of the sediment plume 02 for:

[0030] ,

[0031] Among them, C is the propagation speed of sound waves in seawater; t1 and t2 are the round-trip time of sound waves;

[0032] At this time, the depth of the upper interface of the sediment plume is H 01 for:

[0033] ,

[0034] Where D1 is the distance between the first multibeam echo sounder and the water surface, D1=h1+ l 1 , h1 is the draft of the buoy mechanism, l 1 is the length of the first multibeam echosounder;

[0035] The depth of the interface under the sediment-like flow is H 02 for:

[0036] ,

[0037] in, l 2 is the length of the second multibeam echosounder.

[0038] In step S2, the control component in the first monitoring mechanism controls the motor to rotate, driving the rotating part to rotate; at the same time, the control component controls the hydraulic chamber driving component to supply oil to the annular oil bag, so that the first monitoring mechanism moves upward along the cable, and the pressure value P is monitored in real time by the first pressure sensor in the first monitoring mechanism. 01 ', obtain real-time depth data from the first monitoring agency ;

[0039] When H 01 ≤h 01 '≤H 02 When h, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the first monitoring mechanism are controlled to work; until h 01 '> H 01 or 01When '= h1, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the first monitoring mechanism stop working, and the motor of the first monitoring mechanism stops rotating, the hydraulic drive component of the first monitoring mechanism draws oil from the annular oil bag, so that the oil in the annular oil bag flows back to the hydraulic drive component, and the first monitoring mechanism sinks to the initial position;

[0040] During the process of the second monitoring mechanism rising and rotating along the cable, the pressure value P is monitored in real time by the second pressure sensor in the second monitoring mechanism. 02 ', obtain real-time depth data from the second monitoring agency ;

[0041] When H 01 ≤h 02 '≤H 02 When h, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the second monitoring mechanism are controlled to work; until h 02 '> H 01 or 02 When '=0.5 h0, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the second monitoring mechanism stop working, and the motor of the second monitoring mechanism stops rotating, the hydraulic drive component of the second monitoring mechanism draws oil from the annular oil bag, so that the oil in the annular oil bag flows back to the hydraulic drive component, and the second monitoring mechanism sinks to its initial position.

[0042] During the rising process of the monitoring mechanism, the actual oil supply to the annular oil bag during the initial action of the monitoring mechanism is V1>V0′.

[0043] ,

[0044] After the monitoring mechanism has a rising speed value, the actual oil supply to the annular oil bag is V1=V0, so that the monitoring mechanism moves upward at a uniform speed along the cable.

[0045] ,

[0046] in, is the density of the liquid; m is the weight of the monitoring mechanism; V is the volume of the monitoring mechanism; g is the acceleration of gravity; v is the rising speed; k represents the resistance encountered by the monitoring mechanism during its rise and v 2 The proportionality coefficient between

[0047] When the monitoring mechanism starts to prepare to move downward, the actual oil pumping amount of the annular oil bag V3>V2',

[0048] ,

[0049] After the monitoring mechanism has a descending speed value, the actual oil pumping amount of the annular oil bag V3=V2, so that the monitoring mechanism sinks at a uniform speed along the cable.

[0050] ,

[0051] Among them, V m1 ' is the volume when the monitoring mechanism moves to the top.

[0052] During the floating process of the device, the turbidity meter inverts the measured turbidity at (x0, y0, z0), z0∈(H 01 , H 02 ) Sediment concentration SSC at any depth on the axis;

[0053] As the monitoring mechanism floats and rotates, the acoustic Doppler flow profiler is used to measure the flow velocity profiler outside the mechanism within the range r1 and the depth from H 01 To H 02 Sediment concentrations throughout the area;

[0054] The turbidity meter measurement results and the acoustic Doppler current profiler measurement results are integrated and processed to finally obtain (x0, y0, z0), z0∈(H 01 , H 02 ) is the sediment concentration in the cylindrical area formed by the axis and the surrounding radius r0+r1, where r0 is the radius of the disk in the monitoring mechanism and r1 is the horizontal monitoring range of the acoustic Doppler current profiler.

[0055] The first monitoring mechanism and the second monitoring mechanism analyze the sediment concentration in the cylindrical area and obtain the maximum sediment concentration SSCm. According to the angle α1 recorded by the angle sensor corresponding to SSCm, the distance R1 recorded by the acoustic Doppler flow profiler, and the depth h1' recorded by the pressure sensor, the coordinates of the position with the highest concentration (x1, y1, z1) are obtained as follows:

[0056] ,

[0057] ,

[0058] ,

[0059] According to the angle α1 and distance R1 of (x1, y1) relative to the original position (x0, y0), the walking mechanism is moved R1 distance in the direction of α1 so that the device reaches the position (x1, y1).

[0060] Repeat step S2 at the position (x1, y1), find the next position with the highest concentration (x2, y2, z2), and use the walking mechanism to move the device to the position (x2, y2);

[0061] Repeat step S2 for the nth time and get (x n ,yn , z n ), z n ∈(H n1 , H n2 ) (n=1,2,3,...) The axis and the surrounding radius are r0+r n The sediment concentration in the cylindrical area formed by the walking mechanism is α n Direction Movement R n distance, can reach the position (x n+1 ,y n+1 ), until the source of the sediment plume is finally traced;

[0062] Interpolation is performed on the upper and lower endpoints of every two adjacent axes to supplement the values. The axes obtained by interpolation are:

[0063] ;

[0064] The corresponding end points of the above adjacent axes are connected in sequence to form an upper and a lower curve, and the two curves constitute a longitudinal section from the initial point to the source of the sediment plume and close to the midline of the plume diffusion.

[0065] After finding the source of the sediment plume, the sediment plume diffusion curve is obtained through the following steps:

[0066] (i) Assume that the source of the sediment plume is point O, and the monitoring equipment is located at point O1 near the source. The monitoring equipment repeats step S2 to obtain the sediment concentration in the cylindrical area;

[0067] (ii) Connect OO1, the intersection of OO1 and the annular boundary of the cylindrical area is C1, and a perpendicular line is drawn through O1 to OO1. The intersection points of the perpendicular line and the annular boundary of the cylindrical area are A1 and B1 respectively. The monitoring agency calculates the average value of all concentration data of the fan-shaped area enclosed by A1O1C1 and the fan-shaped area enclosed by B1O1C1, and obtains SSC A1 and SSC B1 ;

[0068] 3. Determine SSC A1 and SSC B1 Compliance If it meets the requirements, the point is determined to be located on the midline of the sediment plume diffusion; if it does not meet the requirements, the monitoring device is driven several times to move to the position with the highest concentration within the monitoring range of the position, and the SSC is obtained again after the position is moved. A1# and SSC B1# , and determine whether it meets the above formula, until the position point O1 that meets the above formula is found;

[0069] (iv) driving the monitoring device to move to point O2 along the extension line of OO1, repeating steps (i) to (iii) to obtain point O2 located on the midline of the sediment plume diffusion;

[0070] (V) Repeat steps (I) to (IV) to obtain several points O q (q=1,2,3…), when the sediment plume concentration at the location reached by the monitoring equipment is so low that the instrument cannot measure it, the monitoring equipment stops operating;

[0071] The obtained points O q The sediment plume diffusion centerline is obtained by connecting them in sequence, and several axes (x q* ,y q* , z q* ), z q* ∈(H q1* , H q2* ) (q=1,2,3...), between every two adjacent axes, interpolation method is used to supplement the data according to the upper endpoints of the two adjacent axes and the lower endpoints of the two adjacent axes;

[0072] The corresponding endpoints of the above adjacent axes and the supplementary data are connected in sequence to form an upper and a lower curve. These two curves constitute the longitudinal section of the sediment plume from the source along the midline of the sediment plume diffusion to the end of the plume diffusion. In addition, the sediment concentration within the surrounding range of the longitudinal section can also be obtained.

[0073] The beneficial effects of the present invention are:

[0074] (1) This method can form a cylindrical three-dimensional monitoring space at a specified location to accurately capture the sediment plume and monitor the concentration of the sediment plume;

[0075] (2) In this method, the monitoring equipment can be controlled to continuously move toward the location with high sediment concentration. During this process, the monitoring equipment moves toward the area with narrower upper and lower cross-sections of the plume and higher plume concentration, and ultimately the source of the sediment plume can be tracked, thus achieving the tracing of the sediment plume.

[0076] (3) This method can be used to obtain a longitudinal section from the initial point to the source of the sediment plume and close to the plume diffusion centerline, as well as the sediment concentration in the surrounding area of ​​the longitudinal section. This method can also be used to obtain a longitudinal section of the diffusion curve of the sediment plume along its diffusion centerline, as well as the sediment concentration in the surrounding area of ​​the longitudinal section, thereby characterizing the morphology of the plume diffusion, making up for the incomplete monitoring of the sediment plume diffusion process during the source tracing process, which is of great significance to the study of the property transformation, evolution law and final destination of the sediment plume. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 It is a state diagram of the monitoring equipment after it is released into the water;

[0078] Figure 2 It is a state diagram of the monitoring equipment recording its position and water depth information;

[0079] Figure 3 It is a state diagram of the upper and lower interfaces of the sediment plume detected by the monitoring equipment;

[0080] Figure 4 is a state diagram of a cylindrical monitoring area of ​​a sediment plume formed during the ascent and rotation of the first monitoring mechanism along the cable;

[0081] Figure 5 is a state diagram of a cylindrical monitoring area of ​​a sediment plume formed during the ascent and rotation of the second monitoring mechanism along the cable;

[0082] Figure 6 It is a state diagram of the downward movement of the cable when the monitoring agency completes the monitoring work;

[0083] Figure 7 It is a state diagram of the monitoring mechanism moving down along the cable to the initial state;

[0084] Figure 8 It is a state diagram of the entire monitoring equipment moving to the position with the highest sediment concentration;

[0085] Fig. 9 It is a schematic diagram of a longitudinal section from the initial point to the source of the sediment plume and close to the midline of the plume diffusion obtained by the method described in the present application;

[0086] Fig.10 It is a schematic diagram of the monitoring equipment moving to point O1 near the source when the sediment plume diffusion curve is obtained using this method;

[0087] Fig.11 It is a schematic diagram for redetermining the position of point O1;

[0088] Fig.12 It is a schematic diagram of the monitoring equipment moving along the extension line of OO1 to O2;

[0089] Fig.13 It is a schematic diagram for redetermining the position of point O2;

[0090] Fig.14 It is a schematic diagram of the whole process of monitoring equipment tracking and monitoring along the center line of sediment plume diffusion;

[0091] Fig.15 It is a schematic diagram of the structure of the monitoring equipment;

[0092] Fig.16 It is a structural schematic diagram of the buoy mechanism;

[0093] Fig.17 It is a schematic diagram of the structure of the monitoring organization;

[0094] Fig.18 is a schematic diagram of the cross-sectional structure of the upper and lower moving parts of the first monitoring mechanism;

[0095] Fig.19 is a schematic cross-sectional structural diagram of a rotating portion of a first monitoring mechanism;

[0096] Fig. 20 It is a structural diagram of the walking mechanism.

[0097] In the figure: 1 buoy mechanism; 2 walking mechanism; 3 cable; 4 weight; 5 floating body; 6 first monitoring mechanism; 7 second monitoring mechanism; 8 buoy body; 9 support frame; 10 solar panel; 11 GPS; 12 first multi-beam echo sounder; 13 up and down moving part; 14 rotating part; 15 connecting rod; 16 cylindrical silo; 17 sealed cabin; 18 annular oil bag; 19 hydraulic drive component; 20 control component; 21 motor; 22 power supply; 23 rotating disk; 24 bearing; 25 ring gear; 26 pinion; 27 first pressure sensor; 28 turbidity meter; 29 angle sensor; 30 acoustic Doppler flow profiler; 31 walking silo; 32 gear; 33 track; 34 third pressure sensor; 35 second multi-beam echo sounder. DETAILED DESCRIPTION

[0098] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0099] In the following description, specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of other ways than those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0100] The method for intelligent tracking and monitoring of the migration process of marine sediment plume described in the present invention comprises the following specific steps.

[0101] In the first step, the equipment for monitoring the sediment plume is dropped to a designated location in the ocean using the ship's lifting equipment.

[0102] For sea areas where sediment plumes are likely to exist during in-situ ocean observations or satellite remote sensing observations, sediment plume monitoring equipment can be deployed at a certain location in the area. The monitoring equipment is dropped into the ocean using the lifting equipment on the ship.

[0103] like Fig.15 As shown, the sediment plume monitoring device includes a buoy mechanism 1 and a walking mechanism 2. The walking mechanism 2 is located below the buoy mechanism 1. The buoy mechanism 1 and the walking mechanism 2 are connected by a cable 3. A weight 4 and a floating body 5 are fixed on the cable 3. A first monitoring mechanism 6 is provided on the cable between the buoy mechanism 1 and the weight 4. A second monitoring mechanism 7 is provided on the cable between the floating body 5 and the walking mechanism 2. Both the first monitoring mechanism 6 and the second monitoring mechanism 7 can move up and down along the cable 3.

[0104] like Fig.16 As shown, the buoy mechanism 1 includes a buoy body 8, a support frame 9 is provided on the top of the buoy body 8, and a solar panel 10 is arranged on the support frame 9. The solar panel 10 can convert solar energy into electrical energy, thereby providing electrical energy for the operation of the entire buoy mechanism. A GPS 11 for sensing the position coordinate information of the device is provided on the top of the support frame 9. A first multi-beam echo sounder 12 with an opening facing is provided at the bottom of the buoy body 8.

[0105] The structures of the first monitoring mechanism and the second monitoring mechanism are completely the same, so in this embodiment, the structure of the monitoring mechanism is specifically described by taking the first monitoring mechanism as an example. Figures 17 to 19 As shown, the first monitoring mechanism includes an up-and-down moving part 13 and a rotating part 14. The up-and-down moving part 13 is located above the rotating part 14, and the up-and-down moving part 13 and the rotating part 14 are connected by a connecting rod 15.

[0106] The upper and lower moving parts include an upper cylindrical silo 16 and a lower sealed silo 17. The cylindrical silo 16 is open, so it is connected to the seawater outside. An annular oil bag 18 is arranged in the cylindrical silo 16. A hydraulic drive component 19, a control component 20, a motor 21 and a power supply 22 are arranged in the sealed silo 17. The power supply provides electrical energy for the hydraulic drive component, the control component and the motor. The control component is connected to the hydraulic drive component, the motor and the power supply respectively. The oil outlet of the hydraulic drive component 19 is connected to the annular oil bag 18 through an oil pipeline.

[0107] The rotating part includes a rotating disc 23 and a bearing 24 located in the middle of the rotating disc. The bearing 24 is fixedly connected to the lower part of the connecting rod 15, and the rotating disc 23 and the bearing 24 are rotationally connected. A ring gear 25 is fixed to the middle of the top surface of the rotating disc 23. The ring gear 25 and the pinion 26 on the outside thereof are meshed with each other, and the pinion 26 is transmission-connected to the output shaft of the motor 21, that is, the motor can drive the gear to rotate during operation.

[0108] The top surface of the rotating disc 23 is also provided with a pressure sensor 27, a turbidity meter 28, an angle sensor 29 and an acoustic Doppler flow profiler 30. The above sensors are used to monitor the sediment concentration.

[0109] like Fig. 20 As shown, the walking mechanism 2 includes a walking chamber 31 and crawler walking parts located on two symmetrical outer sides of the walking chamber. The crawler walking part includes several gears 32 and crawler tracks 33 wound on the gears. During the rotation of the gears 32, the crawler tracks 33 are rotated by the meshing between the gears 32 and the crawler tracks 33. During the simultaneous movement of the crawler walking parts on both sides, the crawler tracks on both sides rotate simultaneously, so that the walking mechanism drives the entire device to walk on the seabed. A third pressure sensor 34 and a second multi-beam echo sounder 35 with an opening upward are fixed on the top surface of the walking chamber.

[0110] like Figure 1 As shown in the figure, when the device sinks until the traveling mechanism contacts the seabed, the buoyancy of the buoy mechanism drives the entire device to stand upright in the seawater. In the initial state, the first monitoring mechanism 6 falls along the cable under the action of its own weight until it contacts the weight 4, and the second monitoring mechanism 7 falls along the cable under the action of its own weight until it contacts the traveling mechanism 2. The weight 4 and the floating body 5 are located in the middle of the entire device.

[0111] The second step is to operate the sediment plume monitoring equipment and record the location of the equipment and water depth information at all times.

[0112] like Figure 2 As shown, a three-dimensional coordinate system is established with the location of the buoy mechanism as the origin. The location coordinates (x0, y0) of the device at this time are recorded by GPS. At this time, the first pressure sensor in the first monitoring mechanism, the second pressure sensor in the second monitoring mechanism, and the third pressure sensor on the walking mechanism respectively sense and record the current location P 01 , P 02 , P 03 .

[0113] The relationship between water pressure P and depth h can be expressed as:

[0114] ,

[0115] Where ρ is the density of seawater and g is the acceleration due to gravity.

[0116] The above formula can be used to obtain the seawater depth h0 and the depth h of the first monitoring organization. 01 , and the depth h of the second monitoring mechanism 02 .

[0117] ,

[0118] ,

[0119] .

[0120] In the third step, the interface position information of the sediment plume is measured respectively by the first multi-beam echo sounder on the buoy mechanism and the second multi-beam echo sounder on the walking mechanism. The interface position information of the sediment plume monitored by the first multi-beam echo sounder is sent to the control component of the first monitoring mechanism, and the interface position information of the sediment plume monitored by the second multi-beam echo sounder is sent to the control component of the second monitoring mechanism.

[0121] In the present application, the first multi-beam echo sounder emits a sound wave pulse of a certain frequency into the seawater below it, and the second multi-beam echo sounder emits a sound wave pulse of a certain frequency into the seawater above it. When the sound wave encounters an obstacle, it is reflected. According to the round-trip time of the sound wave and the propagation speed of the sound wave in the measured water area, the distance L between the plume interface and the corresponding multi-beam echo sounder can be obtained as:

[0122] ,

[0123] Among them, C is the propagation speed of sound waves in seawater; t is the round-trip time of sound waves.

[0124] Therefore, the distance L between the first multibeam echo sounder with its opening downward and the upper interface of the sediment plume in the buoy mechanism is 01 for:

[0125] ,

[0126] The distance L between the second multi-beam echo sounder with its opening upward and the lower interface of the sediment plume in the walking mechanism 02 for:

[0127]

[0128] like Figure 3 As shown in Figure 2, when the sediment plume monitoring device is at position (x0, y0), the depth of the upper interface of the sediment plume is H 01 for:

[0129] ,

[0130] Where D1 is the distance between the first multibeam echo sounder and the water surface, D1=h1+ l 1 , h1 is the draft of the buoy mechanism, l 1 is the length of the first multibeam echo sounder.

[0131] The depth of the interface under the sediment-like flow is H 02 for:

[0132] ,

[0133] in, l 2 is the length of the second multibeam echosounder.

[0134] In the fourth step, based on the plume position information obtained in the third step, the monitoring mechanism moves up and down and rotates to monitor the plume concentration.

[0135] In the first monitoring mechanism, the control component controls the hydraulic drive component to operate and supply oil to the annular oil bag. The volume of the annular oil bag gradually increases. At this time, the volume of the first monitoring mechanism also increases, and the buoyancy of the first monitoring mechanism also increases, so that the first monitoring mechanism moves upward along the cable. In the process of the first monitoring mechanism moving upward, if it is to achieve a uniform rise, it needs to meet the following conditions:

[0136] ,

[0137] Right now: ,

[0138] in, is the liquid density; m is the weight of the first monitoring mechanism; V is the volume of the first monitoring mechanism; V0 is the oil supply; g is the gravitational acceleration; f is the resistance experienced by the first monitoring mechanism, which is proportional to the square of the rising speed v.

[0139] Therefore, the oil supply amount V0 to the annular oil bag during the ascending process of the first monitoring mechanism is:

[0140] ,

[0141] In the actual working process, when the first monitoring mechanism starts to move from rest, v=0, and the oil supply V0′ of the annular oil bag in the first monitoring mechanism is:

[0142] ,

[0143] In addition, the process of the first monitoring mechanism moving from rest to uniform motion requires an acceleration. Therefore, when the first monitoring mechanism initially moves, the actual oil supply to the oil bag is V1>V0′. After the first monitoring mechanism has a certain rising speed value, V1=V0 is made, so that the first monitoring mechanism floats up at a uniform speed.

[0144] When the first monitoring mechanism reaches the upper interface of the sediment plume or approaches the buoy system, it begins to prepare to move downward. At this time, the hydraulic drive component needs to extract oil from the annular oil bag to return the oil in the annular oil bag to the hydraulic drive component. During the oil return process, the volume of the annular oil bag gradually decreases, and the volume of the first monitoring mechanism decreases accordingly, and the buoyancy of the first monitoring mechanism also decreases accordingly, so that the first monitoring mechanism moves downward along the cable. During the downward movement of the first monitoring mechanism, if it is to achieve a uniform descent, it needs to meet the following requirements:

[0145] ,

[0146] Right now: ,

[0147] Among them, V m1 ' is the volume when the first monitoring mechanism moves to the top; V2 is the oil pumping volume.

[0148] Therefore, the oil extraction amount V2 of the annular oil bag during the descent of the first monitoring mechanism is:

[0149] ,

[0150] In the actual working process, when the first monitoring mechanism starts to prepare to move downward, the oil extraction amount V2′ of the annular oil bag in the first monitoring mechanism is:

[0151] ,

[0152] When the first monitoring mechanism begins to prepare for downward movement, the actual oil pumping amount V3 of the oil bag is greater than V2′. After the first monitoring mechanism has a certain descending speed value, the actual oil pumping amount V3 is made equal to V2, so that the first monitoring mechanism sinks at a uniform speed.

[0153] Since the operating principles of the first monitoring mechanism and the second monitoring mechanism are the same, the operating principle of the first monitoring mechanism is taken as an example for detailed description in this embodiment, and the operating principle of the second monitoring mechanism is not repeated.

[0154] The float and weight are located at the center of the device, i.e. at a depth of 0.5 h0, i.e. at a depth of h 04 ≈0.5h0, the draft of the buoy system is h1.

[0155] like Figure 4 and Figure 5As shown, the first monitoring mechanism and the second monitoring mechanism both move upward along the cable. For the first monitoring mechanism, the control component controls the motor to rotate at a constant speed n, driving the rotating part to rotate. At the same time, the control component controls the hydraulic drive component to supply oil to the annular oil bag, and the oil supply volume is V1, so that the first monitoring mechanism moves upward at a constant speed along the cable. In this process, the first pressure sensor in the first monitoring mechanism monitors the pressure value P at its position in real time. 01 ',according to , real-time depth data of the first monitoring agency can be obtained 01 '.

[0156] When H 01 ≤h 01 '≤H 02 When h, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the first monitoring mechanism are controlled to work. 01 '> H 01 or 01 When '= h1, the turbidity meter, acoustic Doppler flow profiler, and angle sensor stop working, and the motor of the first monitoring mechanism stops rotating. At the same time, the hydraulic drive component pumps oil from the annular oil bag, so that the oil in the annular oil bag flows back to the hydraulic drive component. The amount of oil pumped is V3, so that the first monitoring mechanism sinks to the initial position at a uniform speed. Figure 6 and Figure 7 shown.

[0157] For the second monitoring mechanism, its control component controls the motor to rotate at a constant speed n, driving its rotating part to rotate, and at the same time controls the hydraulic drive component to supply oil to the annular oil bag of the second monitoring mechanism, and the oil supply amount is V1, so that the second monitoring unit moves upward at a constant speed. During this process, the pressure sensor in the second monitoring mechanism constantly monitors and records the pressure P at its position. 02 ',according to , real-time depth data of the second monitoring agency can be obtained 02 '.

[0158] When H 01 ≤h 02 '≤H 02 At this time, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the second monitoring mechanism work. 02 '> H 01 or 02 When '=0.5 h0, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the second monitoring mechanism stop working. At this time, the motor of the second monitoring mechanism stops rotating, and the hydraulic drive component is controlled to pump oil from the annular oil bag, and the oil pumping amount is V3, so that the second monitoring mechanism sinks to the initial position at a uniform speed.

[0159] Assume that in the first monitoring mechanism and the second monitoring mechanism, the turbidity meter measurement result is turbidity T, and the turbidity has a certain linear relationship with the concentration SSC, that is:

[0160] T = n·SSC + c,

[0161] Therefore, during the floating process of the device, the turbidity meter can invert the current at (x0, y0, z0), z0∈(H 01 , H 02 ) is the sediment concentration SSC at any depth on this axis.

[0162] The working principle of the acoustic Doppler current profiler to monitor sediment concentration is to calculate the water velocity by monitoring the sediment scatterers based on the Doppler effect. Since the scatterers used by the acoustic Doppler current profiler are mainly suspended particles in the water body, the echo intensity obtained can be inverted to obtain the change of suspended matter concentration. The relationship between backscattering intensity and suspended matter concentration can be expressed as:

[0163] ,

[0164] ,

[0165] Where, SSC is the suspended solids concentration; b is a constant, whose value is related to the sediment particle size, suspended solids density, acoustic wave number, and material constant; S is the backscattering intensity, and m is the wave number of the acoustic Doppler current profiler transmitting the acoustic wave; is the root mean square of the cube of the suspended matter particle size; is the suspended matter density; γ is defined as a material constant, which is a function of the elasticity and density of the particles.

[0166] Assuming that the particle size, density and other physical properties of the suspended matter remain stable during the observation period, and the volume backscattering intensity is linearly related to the logarithm of the suspended matter concentration, the concentration of sediment particles SSC can be obtained. At the same time, the acoustic Doppler current profiler is horizontally oriented to the outside of the monitoring mechanism, and the horizontal range that can be monitored is recorded as r1. The angle sensor always records the direction of the acoustic Doppler current profiler. As the monitoring mechanism floats and rotates, the acoustic Doppler current profiler can measure the range of r1 outside the monitoring mechanism and the depth from H 01 To H 02 Sediment concentrations throughout the area.

[0167] The data of the turbidity meter measurement results and the acoustic Doppler current profiler measurement results are integrated and processed, and finally (x0, y0, z0) can be obtained, z0∈(H 01 , H 02 ) The sediment concentration in the cylindrical area formed by the axis and the surrounding radius r0+r1 is as follows: Figure 5The cylindrical area in the figure is shown in Figure 1. Where r0 is the radius of the disk in the monitoring mechanism, and r1 is the horizontal monitoring range of the acoustic Doppler current profiler.

[0168] In the fifth step, the control components in the first monitoring mechanism and the second monitoring mechanism analyze the sediment concentration data, obtain the position with the highest sediment concentration within the range that it can monitor, record its distance and direction, and send control instructions to the walking mechanism.

[0169] The result obtained in the fourth step is (x0, y0, z0), z0∈(H 01 , H 02 ) The sediment concentration in the cylindrical area formed by this axis and the surrounding radius r0+r1. The control components of the first monitoring mechanism and the second monitoring mechanism compare all the data and analyze the maximum sediment concentration SSCm. According to the angle α1 recorded by the angle sensor corresponding to SSCm, the distance R1 recorded by the acoustic Doppler velocity profiler, and the depth h1' recorded by the pressure sensor, the coordinates of the position with the highest concentration can be obtained as follows:

[0170] ,

[0171] ,

[0172] .

[0173] Step 6: After receiving the control command, the walking mechanism drives the tracks to rotate and drives the entire device to move to the next position (x1, y1).

[0174] According to the angle α1 and distance R1 of the highest concentration position (x1, y1) relative to the original position (x0, y0) obtained in step 5, the tracked vehicle system needs to move R1 distance in the direction of α1 to reach the position (x1, y1), as shown in Figure 8 shown.

[0175] Step 7. Repeat steps 2 to 6 at position (x1, y1) to find the next highest concentration position (x2, y2, z2), and use the walking mechanism to move the device to that position (x2, y2).

[0176] Next, the above steps are repeated. In the process of repeating the above steps, the walking mechanism drives the entire device to move toward the area with narrower upper and lower cross-section range of the plume and higher plume concentration until the source of the plume is found, thereby realizing the tracing of the sediment plume.

[0177] In the eighth step, interpolation is performed between each two adjacent axes according to the upper endpoints of the two adjacent axes and the lower endpoints of the two adjacent axes. By connecting the axis endpoints obtained by the interpolation method and the original axis endpoints in sequence, a longitudinal section from the initial point to the source of the sediment plume and close to the plume diffusion centerline can be formed, such as Figure 8 shown.

[0178] The ninth step is to find the source of the sediment plume and drive the monitoring equipment to move from the source along the center line of the sediment plume diffusion. Similarly, a longitudinal section of the plume diffusion center line and the sediment concentration within the surrounding area of ​​the longitudinal section can be formed, such as Fig.14 As shown. This depicts the morphology of plume diffusion, making up for the incomplete monitoring of sediment plume diffusion during the source tracing process. It is also of great significance to the study of the property transformation, evolution law and final destination of sediment plumes. Example 1

[0179] like Fig. 9 As shown, the first repetition of the above steps 2 to 6 results in (x1, y1, z1), z1∈(H 11 , H 12 ) The sediment concentration in the cylindrical area formed by the axis and the surrounding radius r0+r1. Then move R1 distance in the direction of α1 to reach the position (x2, y2).

[0180] Repeat the above steps 2 to 6 for the second time, and the result is (x2, y2, z2), z2∈(H 21 , H 22 ) The sediment concentration in the cylindrical area formed by the axis and the surrounding radius r0+r2. Then move R2 distance in the direction of α2 to reach the position (x3, y3).

[0181] By analogy, repeat the above steps 2 to 6 for the nth time to obtain (x n ,y n , z n ), z n ∈(H n1 , H n2 ) (n=1,2,3,...) This axis and its surrounding radius are r0+r n The sediment concentration in the cylindrical area formed by n Direction Movement R n distance, can reach the position (x n+1 ,y n+1 ) until the source of the sediment plume is finally traced.

[0182] At the same time, the interpolation method is used to supplement the values ​​between every two adjacent axis lines according to their upper and lower endpoints.

[0183] For example, the axis (x1, y1, z1), z1∈(H 11 , H 12 ) and the axis (x2, y2, z2), z∈(H 21 , H 22 ) by interpolation:

[0184] ;

[0185] The corresponding endpoints of the adjacent axes are connected in sequence to form an upper and lower curve. The two curves constitute a longitudinal section from the initial point to the source of the sediment plume and close to the midline of the plume diffusion, as shown in Fig. 9 It is of great significance to study the property transformation, evolution law and final fate of sediment plumes.

[0186] After finding the source of the sediment plume, assume that the source of the sediment plume is point O, and the monitoring equipment is located at point O1 near the source. At this time, the operating top view of the monitoring equipment is as follows: Fig.10 The hydraulic drive components and motor in the monitoring device act simultaneously, driving the monitoring mechanism to move upward along the cable and rotate simultaneously, forming a cylindrical monitoring area. The specific implementation process is as described in the fourth step above, which will not be repeated here.

[0187] Connect OO1, the intersection of OO1 and the annular boundary of the cylindrical monitoring area is C1. At the same time, draw a perpendicular line through O1 to OO1, and the intersection points of this perpendicular line with the annular boundary of the cylindrical monitoring area are A1 and B1 respectively. The monitoring agency calculates the average value of all concentration data of the fan-shaped area surrounded by A1O1C1 and the fan-shaped area surrounded by B1O1C1 to obtain SSC A1 and SSC B1 .

[0188] ;

[0189] Right now

[0190] ;

[0191] The meaning of the above formula is: according to the law of sediment plume diffusion, the interpolation of the average sediment concentration on both sides of the sediment plume diffusion centerline is within 10%.

[0192] If the SSC A1 and SSC B1 If the above formula is met, it can be determined that the location O1 of the monitoring device is basically located on the midline of the sediment plume diffusion. Record the location coordinates O1 (x1* ,y 1* ) and the measured value (x 1* ,y 1* , z 1* ), z 1* ∈(H 11* , H 12* ) The sediment concentration in the cylindrical area formed by the axis and the surrounding radius r0+r1 is as follows: Fig.10 shown.

[0193] If the SSC A1 and SSC B1 If it does not meet the above formula, the monitoring device is driven to move to the position with the highest concentration within its monitoring range. The specific implementation process is as described in the fifth step above and will not be repeated here. At this position, SSC is recalculated and obtained. A1’ and SSC B1’ , and confirm again whether it meets the above formula. If it meets the above formula, it is determined that the point is basically located on the midline of sediment plume diffusion; if it does not meet the above formula, continue to drive the monitoring equipment to move to the position with the highest concentration within the monitoring range of the position, and re-obtain SSC after moving the position A1# and SSC B1# , and determine whether it meets the above formula until the position point O1 that meets the above formula is found. Fig.11 shown.

[0194] After finding point O1 which is basically located on the midline of the sediment plume diffusion, drive the monitoring device forward along the extension line of OO1 to point O2. Repeat the specific implementation steps at point O1 at point O2 to obtain SSC A2 and SSC B2 .

[0195] judge If it is true, it can be determined that point O2 is basically located on the midline of sediment plume diffusion, and the position coordinates O2 (x 2* ,y 2* ) and the measured value (x 2* ,y 2* , z 2* ), z 2* ∈(H 21* , H 22* ) is the sediment concentration in the cylindrical area formed by the axis and the surrounding radius r0+r1.

[0196] If not, drive the monitoring device to move to the position with the highest concentration within the monitoring range at that position until an O2 point that meets the above formula is found, such as Fig.12 and Fig.13 shown.

[0197] Then, the monitoring device is driven to move forward a certain distance along the extension line of O1O2 to point O3, and the above operation is repeated to obtain several points O q (q=1,2,3...). When the sediment plume concentration at the location reached by the monitoring equipment is low enough and the instrument cannot measure it accurately, the monitoring equipment stops running. q By connecting them one by one, we can get the sediment plume diffusion centerline.

[0198] At the same time, several axes (x q* ,y q* , z q* ), z q* ∈(H q1* , H q2* ) (q=1,2,3...). Between every two adjacent axes, interpolation is performed between the upper endpoints of the two adjacent axes and between the lower endpoints of the two adjacent axes to supplement the data. The corresponding endpoints of the above adjacent axes and the supplemented data are connected in sequence to form an upper and lower curve. These two curves constitute a longitudinal section of the sediment plume from the source along the sediment plume diffusion center line to the end of the plume diffusion. In addition, the sediment concentration within the surrounding range of the longitudinal section can be obtained, such as Fig.14 shown.

[0199] The longitudinal section data makes up for the incomplete monitoring of the sediment plume diffusion process during the tracing process, thereby completely depicting the morphology of the plume diffusion. It is also of great significance for the study of the property transformation, evolution law and final destination of the sediment plume.

[0200] The above is a detailed introduction to the intelligent tracking and monitoring method for the migration process of marine sediment plumes provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The above description of the disclosed embodiments enables professional and technical personnel in this field to implement or use the present invention. Various modifications to these embodiments will be obvious to professional and technical personnel in this field, and the general principles defined in this article can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this article, but will conform to the widest range consistent with the principles and novel features disclosed herein.

Claims

1. An intelligent tracking and monitoring method for the migration process of marine sediment plumes, characterized in that: The following steps are involved: S1. placing a device for monitoring sediment plumes at a designated location in the ocean, recording the location and water depth information of the device, and measuring the interface location information of the sediment plumes; In step S1, a three-dimensional coordinate system is established with the location of the buoy mechanism as the origin. The location coordinates of the monitoring device are (x0, y0). The first pressure sensor in the first monitoring mechanism, the second pressure sensor in the second monitoring mechanism, and the third pressure sensor on the walking mechanism respectively sense and record the current location P 01 , P 02 , P 03 , thus obtaining the seawater depth h0 and the depth h of the first monitoring mechanism 01 , and the depth h of the second monitoring mechanism 02 : Measuring the upper interface position information of the sediment plume by a first multi-beam echo sounder, and sending the detected interface position information of the sediment plume to the control component of the first monitoring mechanism; measuring the lower interface position information of the sediment plume by a second multi-beam echo sounder, and sending the detected interface position information of the sediment plume to the control component of the second monitoring mechanism; The distance L between the first multibeam echo sounder of the buoy mechanism and the upper interface of the sediment plume 01 for: The distance L between the second multi-beam echo sounder of the walking mechanism and the lower interface of the sediment plume 02 for: Among them, C is the propagation speed of sound waves in seawater; t1 and t2 are the round-trip time of sound waves; At this time, the depth of the upper interface of the sediment plume is H 01 for: Wherein, D1 is the distance between the first multi-beam echo sounder and the water surface, D1=h1+l1, h1 is the draft of the buoy mechanism, and l1 is the length of the first multi-beam echo sounder; The depth of the interface under the sediment-like flow is H 02 for: Wherein, l2 is the length of the second multibeam echo sounder; S2. Monitor the plume concentration to obtain the sediment concentration in the cylindrical area, analyze the sediment concentration data to obtain the position of the highest sediment concentration, and move the monitoring equipment to the position of the highest sediment concentration; In step S2, the control component in the first monitoring mechanism controls the motor to rotate, driving the rotating part to rotate; at the same time, the control component controls the hydraulic chamber driving component to supply oil to the annular oil bag, so that the first monitoring mechanism moves upward along the cable, and the pressure value P is monitored in real time by the first pressure sensor in the first monitoring mechanism. 01 ', obtain real-time depth data from the first monitoring agency When H 01 ≤h 01 '≤H 02 When h, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the first monitoring mechanism are controlled to work; until h 01 '>H 01 or 01 When '=h1, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the first monitoring mechanism stop working, and the motor of the first monitoring mechanism stops rotating, the hydraulic drive component of the first monitoring mechanism draws oil from the annular oil bag, so that the oil in the annular oil bag flows back to the hydraulic drive component, and the first monitoring mechanism sinks to the initial position; During the process of the second monitoring mechanism rising and rotating along the cable, the pressure value P is monitored in real time by the second pressure sensor in the second monitoring mechanism. 02 ', obtain real-time depth data from the second monitoring agency When H 01 ≤h 02 '≤H 02 When h, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the second monitoring mechanism are controlled to work; until h 02 '>H 01 or 02 When '=0.5h0, the turbidity meter, acoustic Doppler flow profiler and angle sensor of the second monitoring mechanism stop working, and the motor of the second monitoring mechanism stops rotating, the hydraulic drive component of the second monitoring mechanism draws oil from the annular oil bag, so that the oil in the annular oil bag flows back to the hydraulic drive component, and the second monitoring mechanism sinks to the initial position; During the floating process of the device, the turbidity meter inverts the measured turbidity at (x0, y0, z0), z0∈(H 01 , H 02 ) Sediment concentration SSC at any depth on the axis; As the monitoring mechanism floats and rotates, the acoustic Doppler flow profiler is used to measure and invert the external r1 range of the monitoring mechanism and the depth from H 01 To H 02 Sediment concentrations throughout the area; The turbidity meter measurement results and the acoustic Doppler current profiler measurement results are integrated and processed to finally obtain (x0, y0, z0), z0∈(H 01 , H 02 ) Sediment concentration in the cylindrical area formed by the axis and the surrounding radius r0+r1, where r0 is the radius of the disk in the monitoring mechanism and r1 is the horizontal monitoring range of the acoustic Doppler current profiler; The first monitoring mechanism and the second monitoring mechanism analyze the sediment concentration in the cylindrical area and obtain the maximum sediment concentration SSCm. According to the angle α1 recorded by the angle sensor corresponding to SSCm, the distance R1 recorded by the acoustic Doppler current profiler, and the depth h1' recorded by the pressure sensor, the coordinates of the position with the highest concentration (x1, y1, z1) are obtained as follows: x1=(r0+R1)cosα1, y1=(r0+R1)sinα1, z1=h'1, According to the angle α1 and distance R1 of (x1, y1) relative to the original position (x0, y0), the walking mechanism is moved R1 distance in the direction of α1, so that the device reaches the position (x1, y1); Repeat step S2 at position (x1, y1) to find the next position with the highest concentration (x2, y2, z2), and use the walking mechanism to move the device to position (x2, y2); S3, after the monitoring device is moved to the position, step S2 is repeated to find the position of the next maximum sediment concentration again, and the monitoring device is moved again to the position of the maximum sediment concentration obtained in this step; Repeat the above operation, and move the monitoring equipment toward the area with narrower upper and lower cross-sections of the plume and higher plume concentration until the source of the sediment plume is found; Repeat step S2 for the nth time and get (x n ,y n , z n ), z n ∈(H n1 , H n2 )(n=1,2,3,……) the axis and the surrounding radius are r0+r n The sediment concentration in the cylindrical area formed by the walking mechanism is α n Direction Movement R n Distance, can reach the position (x n+1 ,y n+1 ) until the source of the sediment plume is finally traced; S4. After finding the source of the sediment plume, drive the device to move along the center line of the sediment plume diffusion from the source to monitor the diffusion process of the sediment plume.

2. The method for intelligent tracking and monitoring of marine sediment plume migration process according to claim 1, characterized in that: The sediment plume monitoring equipment comprises: The buoy mechanism is connected to the running mechanism below it through a cable, and a first multi-beam echo sounder with an opening downward is fixed on the bottom surface of the buoy mechanism; A walking mechanism, a top surface of which is fixed with a third pressure sensor and a second multi-beam echo sounder; The weight and float are located at the center of the device; Monitoring mechanisms are respectively arranged on the cables between the buoy mechanism and the weight, and on the cables between the floating body and the walking mechanism bracket, and the monitoring mechanisms move up and down and rotate along the cables.

3. The intelligent tracking and monitoring method for marine sediment plume migration process according to claim 2 is characterized in that: Monitoring agencies include: The upper and lower moving parts include an upper cylindrical silo and a lower sealed silo. The cylindrical silo is open and an annular oil bag is arranged inside the cylindrical silo. The sealed silo is provided with a hydraulic drive component, a control component, a motor and a power supply. The hydraulic drive component is connected to the annular oil bag through an oil pipe. The rotating part includes a rotating disc and a bearing located in the middle of the rotating disc, the rotating disc is rotatably connected to the bearing, a ring gear is fixed at the center of the top surface of the rotating disc, the ring gear and the pinion gear on the outside thereof are meshed with each other, the pinion gear is drivingly connected to the output shaft of the motor, and a pressure sensor, a turbidity meter, an angle sensor and an acoustic Doppler flow profiler are arranged on the top surface of the rotating disc; Connecting rod, the bottom of the sealed chamber is fixedly connected to the bearing through the connecting rod, and the cable passes through the upper and lower moving parts, the connecting rod and the rotating part in sequence; The monitoring mechanism between the buoy mechanism and the weight is the first monitoring mechanism, and the pressure sensor in the first monitoring mechanism is the first pressure sensor; the monitoring mechanism between the floating body and the walking mechanism is the second monitoring mechanism, and the pressure sensor in the second monitoring mechanism is the second pressure sensor.

4. The method for intelligent tracking and monitoring of marine sediment plume migration process according to claim 1, characterized in that: During the rising process of the monitoring mechanism, the actual oil supply to the annular oil bag during the initial action of the monitoring mechanism is V1>V0'. After the monitoring mechanism has a rising speed value, the actual oil supply to the annular oil bag is V1=V0, so that the monitoring mechanism moves upward at a uniform speed along the cable. Wherein, v is the density of the liquid; m is the weight of the monitoring mechanism; V is the volume of the monitoring mechanism; g is the acceleration of gravity; v is the rising speed; k represents the proportional coefficient between the resistance encountered by the monitoring mechanism during its ascent and v2; During the descent of the monitoring mechanism, when the monitoring mechanism begins to prepare for downward movement, the actual oil pumping amount of the annular oil bag V3>V2', After the monitoring mechanism has a descending speed value, the actual oil pumping amount of the annular oil bag V3 = V2, so that the monitoring mechanism sinks at a uniform speed along the cable. Among them, V m1 ' is the volume when the monitoring mechanism moves to the top.

5. The method for intelligent tracking and monitoring of marine sediment plume migration process according to claim 1, characterized in that: Interpolation is performed on the upper and lower endpoints of every two adjacent axes to supplement the values. The axes obtained by interpolation are: The adjacent axes, and (x n ,y n , z n ), z n ∈(H n1 , H n2 ) are connected in sequence to form an upper and a lower curve. The two curves constitute a longitudinal section from the initial point to the source of the sediment plume and close to the midline of the plume diffusion.

6. The method for intelligent tracking and monitoring of marine sediment plume migration process according to claim 1, characterized in that: After finding the source of the sediment plume, the sediment plume diffusion curve is obtained through the following steps: (i) Assuming that the source of the sediment plume is point O, the monitoring equipment is located at point O1 near the source, and the monitoring equipment repeats step S2 to obtain the sediment concentration in the cylindrical area; (ii) Connect OO1, the intersection of OO1 and the annular boundary of the cylindrical area is C1, and at the same time, a perpendicular line is drawn through O1 to OO1, and the intersection points of the perpendicular line with the annular boundary of the cylindrical area are A1 and B1 respectively. The monitoring agency calculates the average value of all concentration data of the fan-shaped area surrounded by A1O1C1 and the fan-shaped area surrounded by B1O1C1, and obtains SSC A1 and SSC B1 ; (III) Determine SSC A1 and SSC B1 Compliance with |SSC A1 -SSC B1 |≤5%(SSC A1 +SSC B1 ), if it meets the requirement, the point is determined to be located on the midline of sediment plume diffusion; if it does not meet the requirement, the monitoring device is driven several times to move to the position with the highest concentration within the monitoring range of the position, and the SSC is obtained again after the position is moved. A1# and SSC B1# , and determine whether it meets the above formula, until the position point O1 that meets the above formula is found; (iv) driving the monitoring device to move along the extension line of OO1 to point O2, repeating steps (i) to (iii) to obtain point O2 located on the midline of the sediment plume diffusion; (V) Repeat steps (I) to (IV) to obtain several points O q (q=1,2,3,……), when the sediment plume concentration at the location reached by the monitoring equipment is so low that the instrument cannot measure it, the monitoring equipment stops operating; The obtained points O q The sediment plume diffusion centerline is obtained by connecting them in sequence, and several axes (x q* ,y q* , z q* ), z q* ∈(H q1* , H q2* )(q=1,2,3,……), between every two adjacent axes, interpolation method is used to supplement data according to the upper endpoints of the two adjacent axes and the lower endpoints of the two adjacent axes; The corresponding endpoints of the above adjacent axes and the supplementary data are connected in sequence to form an upper and a lower curve. These two curves constitute the longitudinal section of the sediment plume from the source along the midline of the sediment plume diffusion to the end of the plume diffusion. In addition, the sediment concentration within the surrounding range of the longitudinal section can also be obtained.

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