CN-120103495-B - Submarine sediment environment dynamic change characteristic inversion method based on three-phase potential

Abstract

The application provides a three-phase potential-based submarine sediment environment dynamic change feature inversion method which comprises in-situ data processing, electrical signal calibration, mathematical model establishment and dynamic change analysis. Signals such as natural potential, resistivity, oxidation-reduction potential and the like are acquired in real time by arranging the submarine electrode array, and the submarine sediment environment characteristics such as the seabed interface position, suspended particle concentration, sediment density, porosity, water content and the like are deduced by adopting an inversion algorithm. The method combines multi-frequency signal analysis, can monitor the submarine sediment environment change in real time, and identify sediment movement and the like. Compared with the prior art such as CN118153411B and CN110411923B, the application covers richer inversion content, the complementarity of potential signals improves the monitoring precision and efficiency, and has stronger adaptability and reliability. The method has lower equipment and maintenance cost, is suitable for large-scale and long-term monitoring, and can provide innovative solutions in the fields of deep sea monitoring, environment evaluation, resource exploration and the like.

Inventors

• PENG SHAOYUAN
• LV XIAOPING
• LIU JIANCHENG
• LI LEI
• Wu Sichuan
• MEI XIANZHI
• DONG FANG
• ZHU XIANMING
• JIA YONGGANG
• Quan Yongzheng

Assignees

• 招商局海洋装备研究院有限公司

Dates

Publication Date

20260505

Application Date

20250312

Claims (5)

1. 1. The submarine sediment environment dynamic change characteristic inversion method based on the three-phase potential is characterized by comprising the following steps of: three-phase potential data acquisition pretreatment, three-phase potential and suspended particle concentration data processing, interface processing, and three-phase potential and sediment property processing; Determining submarine sediment environment data; Finally, realizing the dynamic description of the submarine sediment environment characteristics based on three-phase potential, and further implementing real-time dynamic monitoring; the submarine deposition environment data judgment comprises the steps of carrying out data judgment of submarine deposition environment dynamic change characteristics according to known monitoring data: Firstly, interface position determination is carried out, data of natural potential, resistivity and oxidation-reduction potential are preprocessed, an electrode determination direction is added based on a traditional variational point method model, the interface position can be determined, and the data of the natural potential is set as Assume at a certain moment that For data Vertical distribution data of three-phase potential by using seabed interface position m Is divided into two parts; ; Wherein, the Is a random error independent of each other, has an expected value of 0 and has a common variance Where m, a 1 、α 2 、σ 2 are unknown, a 1 is the natural potential difference of the sediment, a 2 is the natural potential difference of the sea water, Is the total number of the electrodes with the natural potential, Is the position of mutation of the potential difference value of the natural potential, in The mean change of the position is ; Wherein, the Obviously, when When the potential difference is similar in the sea water layer or sediment layer, Smaller or even 0 trending toward, when When the sea water is positioned at the sea bed position, the natural potential difference between the sea water and sediment can be generated Larger, so that, ; At this time, the I.e., the point of failure, i.e., the seabed interface location, To verify the level, the threshold value can be empirically chosen If not, the natural potential electrode is considered to be all in the sea water or sediment, Secondly, judging the concentration of suspended particles, according to the condition of in-situ monitoring data, Natural potential, namely filtering three-phase potential interpolation from top to bottom, wherein after filtering 1/2 of repeated values, the natural potential inversion model has strong correlation with suspended sediment concentration and accords with Gauss Amp function model, and an empirical formula can be obtained according to the natural potential inversion model: ; Wherein, the Represents the potential difference at the reference electrode in units of , Representing suspended particulate matter concentration, wherein the unit is g/L, y 0 、A、x c and omega are respectively stated variable quantities according to the range of potential difference values, assignment can be carried out among different regions, the suspended particulate matter concentration can be respectively judged and identified according to natural potential long-term monitoring data, the whole suspended sediment concentration profile structure is obtained, Resistivity inversion: ; oxidation-reduction potential inversion: ; ; ; ; According to the sediment type, the most suitable suspended particulate matter concentration inversion method is selected after the in-situ test data and the sediment property calibration, Finally, analyzing the basic property of the sediment, and establishing a multiple regression model according to the related data: ; Where a is a constant term, b 1 、b 2 、b 3 is the coefficient to be determined, Is an error term; modeling natural potential difference: ; ; ; Inverting the set of equations: ; ; ; Solving the equations by using an optimization algorithm to solve the unknown sediment density, water content and porosity, and synthesizing the equations to obtain a final model expressed as: ; ; ; the relation between the oxidation-reduction potential and the sediment is that the oxidation-reduction potential is related to the density, the water content and the porosity of the sediment to a certain extent, but the specific mathematical relation is greatly influenced by the environment and experimental conditions, and compared with the prior indoor test calibration, the formula is more accurate, is more suitable for the indoor test and in-situ monitoring, and has more comprehensive coverage; ; ; ; 。
2. 2. The method for inverting the dynamic change characteristics of the submarine sediment environment based on the three-phase potential according to claim 1 is characterized by comprising the steps of collecting and processing data, sequentially inverting submarine sediment, a seabed interface and suspended particulate matter concentration based on a natural potential difference value, resistivity and oxidation in-situ potential, and then processing the submarine sediment, the seabed interface and the suspended particulate matter concentration along with time change, preprocessing the data, namely, preprocessing the input data, further carrying out standard processing on each characteristic, carrying out data with larger distinguishing errors, reserving the data with good quality, carrying out analysis fitting on the data set and the measured data, and further preprocessing by means of neural network learning, wherein the three-phase potential processing is mainly carried out, so that the data accords with the in-situ monitoring; The method comprises the steps of firstly establishing an in-situ monitoring database set, wherein the in-situ monitoring database set comprises the steps of obtaining deep sea in-situ soil body and water body, and mainly comprises suspended particulate matter concentration of the water body, seabed interface position change and basic physical properties of seabed sediment, including basic parameters of density, water content and porosity; the three-phase potential data calibration comprises the steps of carrying out natural potential treatment, firstly analyzing the natural potential according to the obtained electrode parameters, establishing a first electrode ring to an nth electrode ring, carrying out main electrode difference treatment on n is more than or equal to 30, and obtaining a reference electrode difference SPd compared with each electrode ring, wherein each potential difference represents a potential characteristic value aiming at a reference electrode; ; In the formula, SPd is the potential difference value, For the actual measurement of the value of the quantity, For the reference electrode value, Amplification of electrode acquisition Doubling, i.e. shrinking in original value The real potential difference value can be obtained, so that the monitoring difference in the in-situ process is more obvious; the submarine resistivity calibration is carried out, namely a resistivity value is obtained according to in-situ monitoring, interval division processing is carried out, and an average apparent resistivity value in a certain distance is obtained; ; In the formula, the current Sum voltage of Constant of electrode Provided by the electrode manufacturer or calibrated by standard solutions The electrical resistivity of the material is determined by the electrical resistivity, Reference error resistivity; According to the formula, the resistivity value can be corrected, compared with the traditional resistivity value, the formula is newly added with error analysis, so that the data can be used for inverting the true submarine redox potential, wherein the redox potential is changed along with the change of temperature according to the current temperature, and the temperature compensation is carried out: ; Wherein ORP T is the corrected redox potential, ORP T0 is the corrected redox potential, alpha is the temperature coefficient, depending on the specific measurement system, the oxidation potential calibration of the measured temperature is increased, the oxidation in-situ potential treatment at the seabed stability monitoring temperature is measured, the influence of salinity on the redox potential is relatively small, but in high salinity water bodies, correction is also needed, and the salinity correction is performed by referring to the specific salinity-ORP relationship.
3. 3. The three-phase potential-based submarine sediment environment dynamic change characteristic inversion method is characterized by comprising the steps of data calibration, namely firstly selecting monitoring data of a target area, and performing numerical fitting according to natural potential interpolation and suspended particulate matter concentration, wherein the concentration change of plume suspended particulate matters is remarkable in the deep sea mining process; natural potential processing, namely, dynamic indoor data change of a submarine sediment environment, wherein the maximum concentration of submarine suspended sediment in a tidal range can reach 8.69 g/L according to the maximum concentration of the suspended sediment in a estuary in still water, the maximum concentration of the submarine suspended sediment in a tidal range can reach 14.2 g/L, the concentration of the submarine suspended sediment in a typhoon in a storm surge period can be increased by 30 times, the concentration range of a suspended sediment solution is 0-20 g/L, the test interval is 0-20 g/L, the precision is 1g/L, and a correlation is established: ; Wherein the method comprises the steps of The concentration of suspended sediment is g/L, SP is natural potential, and the unit is , For the test of the water level height, the unit is cm, Is the salinity of the water, the water is the salt, Temperature in DEG C, DO in mg/L, dissolved oxygen; ; SPM represents the sediment mass of the submarine suspended sediment, RR tests the sediment resistivity reduction, and the unit is% and further analyzed according to the resistivity reduction to obtain a reference resistivity value; And then the resistivity correction is tested indoors: ; Wherein the method comprises the steps of The unit is g/L for suspending sediment concentration, Is resistivity in unit of , Is the salinity of the water, the water is the salt, The specific resistance has a certain logarithmic relationship for the concentration identification of suspended particles for the temperature in DEG C; the relation between oxidation-reduction potential and suspended particulate matter concentration is analyzed by adopting the mass of suspended sediment of the seawater of the south China sea, and the relation analysis of the oxidation-reduction potential of the sediment is: ; ; ; ; Wherein, the Indicating suspended particulate matter concentration, dissolved oxygen concentration C DO , organic matter concentration C OM , ORP representing oxidation-reduction potential, TOC being total organic carbon in the sediment, TN being total organic nitrogen, then the oxidation-reduction potential being related to the total organic carbon and total organic nitrogen of the sediment, a, b being the coefficient of the relationship, the pH is the pH value of the solution, the relative solution concentration of C TOC 、C TN , and the formula indicates that the oxidation-reduction potential is mainly influenced by sediment compared with the traditional indoor test, and the oxidation-reduction potential and the pH of the solution have a negative proportion relationship, so that the nonlinear relationship of the oxidation-reduction potential relative to the solution is obtained.
4. 4. The method for inverting the dynamic change characteristics of the submarine sediment environment based on the three-phase potential according to claim 1, wherein the processing of the three-phase potential and sediment property parameter data comprises the steps of establishing a mathematical relationship among sediment density, water content, porosity and natural potential, wherein the sediment density is determined by the relative proportion of solid particles and pore water; The natural potential is expressed by the following formula: ; Wherein, the Is the density of the solid particles and, Is the water density of the pores, Is porosity, mainly according to the pore water content in sediment The water content is ; Porosity is of ; Wherein, the Is the density of the solid particles and, Is the density of the solid particles and, Is the total volume, and compared with pore water among sediments, the method focuses more on the sediment pore density in the in-situ environment of the submarine sediment compared with the traditional calculation method; and establishing a mathematical model with sediment density, water content and porosity: ; The resistivity and sediment porosity and water content build a mathematical model: ; is the sediment resistivity , Is the resistivity of water , It is the porosity of the deposit that, Is the porosity of saturated water ; Is the sediment resistivity , Is the resistivity of the dried deposit , Is the density g/cm 3 of the deposit mineral, Is the overall density of the deposit, g/cm 3 ; The common effect of porosity, water content and density on resistivity is comprehensively considered through the following model, and sediment property and resistivity fitting calibration is carried out on clay property of a submarine mining area compared with the data of the previous indoor test: ; ; ; ; the oxidation-reduction potential comprehensively considers the common influence of porosity, water content and density on resistivity, Indicating the degree of compaction of the deposit, a higher density may result in lower porosity, which in turn affects the diffusion rate of oxygen and other oxidants, in relation to the content of organic matter, minerals and the degree of compaction of the deposit, and therefore, a higher deposit density tends to correspond to a lower redox potential, ; A, b are empirical constants, the specific value depends on the environment and the type of deposit; Moisture content Directly affecting the availability and diffusion rate of oxygen in the deposit, a higher water content indicates a lower oxygen content, and therefore, ORP tends to decrease with increasing water content, a common empirical formula: ; Indicating the proportion of void volume in the sediment to the total volume, high porosity means that oxygen diffuses faster, ORP is higher, oxygen is difficult to enter at low porosity, ORP is lower, a reducing environment is easy to form, ; Finally, the model is integrated ; The oxidation-reduction potential is associated with the density, the water content and the porosity of the sediment to a certain extent, but the specific mathematical relationship is greatly influenced by the environment and experimental conditions.
5. 5. The three-phase potential-based seafloor depositional environment dynamic change characteristic inversion method as set forth in claim 1, wherein the implementation method comprises: (1) Arranging an electrode array, and acquiring natural potential, resistivity and oxidation-reduction potential electrical signals in real time through the electrode array arranged on the sea bottom; (2) Inverting the electrical signals, processing the electrical signals by using the inversion algorithm, deducing a seabed interface of a deposition environment, and determining the seabed interface according to the combination of three potentials; according to the seabed interface of the deposition environment, the concentration of suspended particles in the deposition environment is calibrated according to the combination of natural potential, resistivity and oxidation-reduction potential; (3) The multi-frequency signal analysis and the noise reduction filtering multi-frequency signal analysis method of the three-phase potential are combined, so that the resolution and the accuracy of inversion are improved; (4) Dynamic monitoring and identification, namely, based on the change of an electrical signal, monitoring the dynamic change characteristics of the submarine deposition environment in real time, and identifying the environment change and the sediment movement.

Description

Submarine sediment environment dynamic change characteristic inversion method based on three-phase potential Technical Field The application relates to the technical field of submarine exploration and ocean engineering geology, in particular to a three-phase potential-based submarine sediment environment dynamic change characteristic inversion method. Background The development of submarine mineral resources and the emission of plumes have led to the dynamic change of the submarine deposition environment. The submarine deposition environment is a transition area between a water body and submarine sediments, and the processes of the submarine sediments, seawater flow and the like in the layer have important influences on a marine ecosystem, resource distribution and engineering structure stability. However, conventional monitoring means (e.g., acoustic, optical, seismic detection, etc.) are often limited by signal attenuation, low resolution, etc. in turbid environments, and it is difficult to obtain accurate data, especially in complex sedimentary layer structures. In contrast, the electrical-based detection method (such as conductivity, resistivity, natural electric field detection and the like) can directly reflect the change of electrical parameters of the submarine sediment, has stronger penetrating power, and can obtain stable measurement results in high-turbidity and deep-layer environments. Along with the fusion development of ocean dynamics, sedimentology and electromagnetic detection technology at present, the promotion of inversion algorithms (such as machine learning and introduction of Kalman filtering) also enables the application of electrical inversion in boundary layer monitoring to be more real-time and accurate. Therefore, the technology for inverting the dynamic change characteristics of the submarine sediment environment based on the electrical method is becoming an important direction in the submarine environment monitoring field, and the deep research of submarine sediment processes, material transportation, engineering geological conditions and the like is promoted. However, the existing inversion method for the submarine sediment environment aiming at the electrical signals is limited by multi-medium uncertainty, the single natural potential signal processing cannot meet the requirement of the existing inversion method, the submarine interface change caused by mining disturbance cannot be uniformly analyzed, and a method capable of carrying out inversion aiming at the submarine sediment environment comprising the concentration of suspended particles, the submarine interface and the uniformity of sediment properties is urgently needed. Disclosure of Invention In order to make up for the defects of the prior art, the application provides a three-phase potential-based submarine sediment environment dynamic change characteristic inversion method. The application provides a three-phase potential-based seabed sediment environment dynamic change characteristic inversion method, which specifically comprises the following steps: three-phase potential data acquisition pretreatment, three-phase potential and suspended particle concentration data processing, interface processing, and three-phase potential and sediment property processing; Determining submarine sediment environment data; finally, the dynamic description of the submarine sediment environment characteristics based on the three-phase potential is realized, and then the real-time dynamic monitoring is implemented. Optionally, three-phase potential data acquisition preprocessing mainly comprises data acquisition and processing, and sequentially inverting the concentration of submarine sediments, seabed interfaces and suspended particles based on a natural potential difference value, resistivity and oxidation in-situ potential, and then processing along with time change; The data preprocessing, which adopts different value ranges for the characteristics of the data, so that the input data needs to be preprocessed, the data with large value ranges is processed, each characteristic is marked for further standard processing, the data with large difference errors are processed, and the data with good quality is reserved; And (3) carrying out analysis fitting on the data set and the measured data, and further carrying out pretreatment, mainly carrying out three-phase potential treatment, so that the data set and the measured data are in line with the corresponding in-situ monitoring. The method comprises the steps of firstly establishing an in-situ monitoring database set, wherein the in-situ monitoring database set comprises the steps of obtaining deep sea in-situ soil and water, and mainly comprises suspended particulate matter concentration of the water, seabed interface position change and basic physical properties of seabed sediment, including basic parameters of density, water content and porosity. The three-phase potential data calib