Method and system for analysis of mars surface degradation and erosion rates based on crater scaling

Abstract

This invention proposes a method and system for analyzing Martian surface degradation and erosion rates based on impact crater classification, relating to the fields of planetary remote sensing and planetary geology. The method includes classifying impact craters into degradation levels and calculating their absolute ages; calculating the average depth and average edge uplift of all impact craters at each degradation level within a defined diameter scale; calculating the impact crater degradation rate and impact crater erosion rate between any two degradation levels based on the absolute ages of impact craters at each degradation level; and fitting these curves to obtain impact crater degradation rate and impact crater erosion rate curves. This invention classifies impact craters into multiple degradation levels based on morphology and degree of damage. Combining the morphological parameters and absolute dating results of each level, it calculates two destructive factors—the surface degradation rate and erosion rate—of the Martian study area, and generates complete degradation rate and erosion rate curves that reflect the changes in the study area over time.

Description

Technical Field

[0001] This invention belongs to the fields of planetary remote sensing and planetary geology, and in particular relates to a method and system for analyzing Martian surface degradation and erosion rates based on impact crater classification. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Mars is the most Earth-like planet in our outer solar system and holds significant scientific value. The Martian surface morphology and climate differ greatly from Earth's, making Martian exploration and research crucial for understanding planetary formation, evolution, and the conditions necessary for life. Impact craters are the most prominent morphological features and structural objects on the Martian surface. Geological processes and atmospheric activity on Mars lead to the degradation and erosion of these craters. The morphology of small-scale (hundred-meter scale) impact craters is more sensitive to the strength of strata and surface modification, reflecting the spatiotemporal distribution of surface erosion and degradation rates in the study area.

[0004] Therefore, the study of impact crater morphology can be used to reveal the degradation and erosion rates of impact craters in different Martian environments, and thus to infer past Martian climate conditions and geological processes. Previous studies on Martian surface erosion and degradation rates based on impact crater morphology mainly suffered from the following two problems:

[0005] (1) Previous studies on the fracturing and burial process caused by geological and weathering processes on the Martian surface have only used the erosion rate as a general indicator, without distinguishing between the erosion rate and the degradation rate. The depth of Martian impact craters decreases over time. The decrease in impact crater depth is mainly due to the filling of Martian aeolian deposits, crater rim collapse, material slippage, and subsequent burial by impact ejecta. Therefore, the surface damage rate derived from the change in impact crater depth is defined as the degradation rate. On the other hand, the decrease in impact crater rim height over time is due to the rounding of the impact crater rim caused by atmospheric and geological processes (e.g., physical and chemical weathering and erosion, frost, micrometeorite impacts). This process can be more closely related to the true Martian surface erosion rate. Therefore, the rate derived from the change in impact crater rim height is defined as the surface erosion rate. The degradation rate and the erosion rate are two different factors for measuring the degree of damage to the Martian surface, with different calculation formulas and meanings, and should be distinguished, calculated, and discussed.

[0006] (2) Previous studies on the degradation of Martian impact craters classified them into two categories based solely on their morphology: fresh impact craters and obviously degraded impact craters. The average erosion thickness of the study area was obtained by calculating the filling volume of the degraded impact crater and then dividing it by the area of ​​the study area. This average erosion rate of the study area was then obtained by dividing it by the geological age of the study area.

[0007] However, the degradation of Martian impact craters is a continuous process. Due to changes in Martian climate and geological processes (volcanoes, glaciers, aeolian formations, etc.) over different eras, it is difficult to determine the rate of destruction of the Martian surface over time using a single erosion rate. Summary of the Invention

[0008] To overcome the shortcomings of the existing technology, this invention provides a method and system for analyzing Martian surface degradation and erosion rates based on impact crater classification. First, impact craters are divided into multiple degradation levels based on morphology and degree of damage. Combining the morphological parameters (depth and crater rim uplift height) and absolute dating results of each level of impact crater, the two destructive factors of surface degradation rate and erosion rate in the Martian study area are calculated, and complete degradation rate and erosion rate curves that can reflect the changes in the study area over time are generated, providing a tool for studying changes in Martian surface climate conditions and geological processes.

[0009] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0010] The first aspect of this invention provides a method for analyzing Martian surface degradation and erosion rates based on impact crater classification.

[0011] A method for analyzing Martian surface degradation and erosion rates based on impact crater classification includes the following steps:

[0012] The impact craters in the study area were classified into degradation levels, and the absolute age of each degradation level impact crater was calculated.

[0013] Calculate the average depth of all impact craters at each degradation level and the average edge uplift of all impact craters at each degradation level, based on the absolute age of impact craters at each degradation level. Calculate the impact crater degradation rate and impact crater erosion rate between any two degradation levels.

[0014] Nonlinear fitting was performed on the impact crater degradation rate and impact crater erosion rate between adjacent degradation levels to obtain impact crater degradation rate curves and impact crater erosion rate curves.

[0015] The second aspect of the present invention provides a system for analyzing Martian surface degradation and erosion rates based on impact crater classification.

[0016] A Martian surface degradation and erosion rate analysis system based on impact crater classification includes:

[0017] The absolute dating module is configured to classify the degradation levels of impact craters within the study area and calculate the absolute age of each degradation level impact crater.

[0018] The impact crater degradation rate and erosion rate calculation module is configured to: calculate the average depth of all impact crater depths at each degradation level and the average edge uplift height of all impact crater edges at each degradation level under a set diameter scale; and calculate the impact crater degradation rate and impact crater erosion rate between any two degradation levels based on the absolute age of the impact crater at each degradation level.

[0019] The fitting module is configured to perform nonlinear fitting on the impact crater degradation rate and impact crater erosion rate between adjacent degradation levels to obtain the impact crater degradation rate curve and impact crater erosion rate curve.

[0020] A third aspect of the present invention provides a computer-readable storage medium having a program stored thereon that, when executed by a processor, implements the steps in the method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in the first aspect of the present invention.

[0021] The fourth aspect of the present invention provides an electronic device including a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in the first aspect of the present invention.

[0022] The above one or more technical solutions have the following beneficial effects:

[0023] This invention provides a method and system for analyzing Martian surface degradation and erosion rates based on impact crater classification. It distinguishes between degradation rate and erosion rate, classifies Martian impact craters in detail (e.g., into seven categories), calculates the absolute age of impact craters with different degrees of degradation and their corresponding degradation and erosion rates, and generates complete degradation and erosion rate curves that reflect the changes in the study area over time. This provides a tool for studying changes in Martian surface climate conditions and geological processes.

[0024] This invention first classifies impact craters into multiple degradation levels based on their morphology and degree of damage. Combining the morphological parameters (depth and rim uplift height) of each level of impact crater with absolute dating results, it calculates two destructive factors: the surface degradation rate and erosion rate of the Mars study area. It then calculates the absolute age of impact craters with different degradation levels and their corresponding degradation and erosion rates, thereby generating a complete time-varying degradation and erosion rate for the study area.

[0025] The method of this invention revealed that fresh impact craters degrade rapidly in their early stages. Over time, the degradation rate decreases by two orders of magnitude and then stabilizes, possibly due to a weakened ability to trap sediments such as sand and dust in the later stages of degradation. The erosion rate of impact craters did not change significantly in the later stages, possibly because the crater filling process reduced the erosive effect of wind and sand on the crater edges. With the decrease in the amount of movable sediment and the reduction in the slope of the impact crater walls, the erosion rate at the crater edges also decreased slowly. Both the edge erosion rate and the depth degradation rate decreased with increasing time scale.

[0026] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0027] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0028] Figure 1 This is a spatial distribution map of impact craters classified by color coding within a study area of ​​approximately 134 square kilometers.

[0029] Figure 2 This is a cumulative size frequency distribution map of impact craters of degradation levels 1 to 7 within the study area.

[0030] Figure 3 This is a graph showing the ideal degradation rate and erosion rate based on a 100m diameter impact crater in the study area.

[0031] Figure 4 This is a flowchart of the method in the first embodiment.

[0032] Figure 5 This is a system structure diagram of the second embodiment. Detailed Implementation

[0033] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0034] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0035] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0036] The overall concept proposed in this invention is as follows:

[0037] Since degradation rate and erosion rate are two different factors for measuring the degree of damage to the Martian surface, with different calculation formulas and meanings, this invention distinguishes between degradation rate and erosion rate. After classifying Martian impact craters in detail (e.g., seven categories) based on morphology and degree of damage, the absolute age of impact craters with different degrees of degradation and their corresponding degradation rate and erosion rate are calculated respectively, thereby generating complete degradation rate and erosion rate of the study area over time.

[0038] Example 1

[0039] This embodiment discloses a method for analyzing Martian surface degradation and erosion rate based on impact crater classification.

[0040] like Figure 4 As shown, the method for analyzing Martian surface degradation and erosion rate based on impact crater classification includes the following steps:

[0041] The impact craters in the study area were classified into degradation levels, and the absolute age of each degradation level impact crater was calculated.

[0042] Calculate the average depth of all impact craters at each degradation level and the average edge uplift of all impact craters at each degradation level, based on the absolute age of impact craters at each degradation level. Calculate the impact crater degradation rate and impact crater erosion rate between any two degradation levels.

[0043] Nonlinear fitting was performed on the impact crater degradation rate and impact crater erosion rate between adjacent degradation levels to obtain impact crater degradation rate curves and impact crater erosion rate curves.

[0044] Analysis of Martian surface degradation and erosion rates based on impact crater classification and dating includes the following four steps:

[0045] Step 1: Determining the absolute age of Mars impact crater classification.

[0046] First, using high-resolution imagery of the study area as a base map, each impact crater was visually interpreted and manually digitized. Three points on the edge of each crater were selected to generate the corresponding boundary circle object. Then, the impact craters in the study area were classified into degradation levels. It is assumed that the impact craters in the study area are divided into n degradation levels based on morphology and degree of degradation, where i is the degradation level, i = 1, 2, ..., n. The number of impact craters in each degradation level is N. iThe diameter of the boundary circle is taken as the diameter of the corresponding impact crater. Impact crater diameter-frequency distributions are constructed for degradation levels 1-2, 1-3, ..., 1-n to determine the absolute age of impact craters at each degradation level. Taking the i-th degradation level impact crater as an example, its dating requires merging impact craters from degradation level 1 to i, statistically analyzing their diameter-number patterns, and then using the cumulative distribution function and impact crater production function to obtain the absolute age T of the i-th degradation level impact crater. i .

[0047] Step 2: Calculate the degradation rate of Martian impact craters. The degradation rate is the degree to which the depth of an impact crater changes over a certain period due to factors such as the migration and filling of aeolian sediments, impacts from small meteorites, gravity-driven material sloping, and the burial of ejecta from new impact craters. Because impact craters of different diameters take different amounts of time to degrade to the same degradation level, and therefore have different degradation rates, impact craters with a diameter of D are uniformly selected when calculating the degradation rate for different degradation levels to eliminate errors caused by differences in the crater's own diameter. Since smaller diameter impact craters are significantly eroded after formation, and some small impact craters have degraded to the point of complete disappearance, larger diameter impact craters should be selected when calculating the degradation rate of Martian impact craters.

[0048] Crater depth is the elevation difference from the top of the crater edge to the deepest point at the bottom of the crater. The average depth of all crater depths is calculated for each degradation level at the diameter D of the study area. Taking the i-th degradation level as an example, its average depth is dave. i :

[0049]

[0050] Where d j This represents the depth of the j-th impact crater at the i-th degradation level.

[0051] The absolute age and average depth of impact craters at each degradation level have been calculated above. Therefore, taking any two degradation levels u and v as examples (u = 1, 2, ..., n-1; v = 2, 3, ..., n, and v > u), the degradation rate Dr(u,v) between the two impact craters is equal to the difference in their average depths divided by the difference in their absolute ages. The formulas for the degradation rates are as follows:

[0052]

[0053] The unit of degradation rate is m / Myr, where Myr is a geoscientific unit of time, meaning millions of years. Where dave... u The average depth of the impact crater representing the uth degradation level, dave v T represents the average depth of the impact crater at the vth degradation level. uThe absolute age of the impact crater representing the uth degradation level in the study area, T v The absolute age of the impact crater representing the V-level degradation in the study area.

[0054] Impact craters degrade more rapidly and experience more dramatic depth decay in the early stages of crater formation. As time progresses, their ability to trap sand and other infill materials weakens, leading to slower degradation in the later stages of crater formation. Because the timescales for each crater class are typically unequal, the degradation rate exhibits a non-linear decline, and the degradation rate gradually decreases with increasing degradation class.

[0055] Step 3: Calculate the erosion rate of Martian impact craters. The erosion rate is typically the rate at which the crater's edge height changes over a given time due to surface processes (e.g., weathering, freeze-thaw cycles, dust storms, etc.). Because impact craters of different diameters take different amounts of time to degrade to the same degradation level, and therefore have different degradation rates, impact craters with a diameter of D are uniformly selected when calculating the degradation rate for different degradation levels to eliminate errors caused by variations in crater diameter. Since smaller diameter impact craters are significantly eroded after formation, and some small impact craters have already degraded to the point of complete disappearance, larger diameter impact craters should be selected when calculating the degradation rate of Martian impact craters.

[0056] The crater edge uplift height is the height difference between the top of the crater edge and the initial plain before impact. The initial plain before impact is represented by a range extending outward from the crater edge by approximately one crater diameter; the top of the crater edge is represented by a range extending inward and outward by 0.1 times the crater diameter, with this 0.2 times diameter range being the range extending inward and outward from the crater edge. First, two buffer zones are drawn: a circular buffer zone extending outward from the crater by one crater diameter (hereinafter referred to as the 2D buffer zone), and an annular buffer zone extending inward and outward by 0.1 times the crater diameter on each side (hereinafter referred to as the 0.2D buffer zone). Next, the boundary lines of the 2D buffer zone are converted into equally spaced points, and elevation values ​​are added to these points. Then, an irregular triangular mesh is constructed by intropolation to simulate the three-dimensional surface of the initial plain before impact, and this three-dimensional surface is converted into a raster surface with the same resolution as the existing elevation raster data (hereinafter referred to as raster A). The existing elevation values ​​within the 2D buffer zone are then extracted to obtain the post-impact raster surface (hereinafter referred to as raster B), and raster C is obtained by subtracting raster A from raster B. The elevation raster values ​​within the 0.2D buffer zone of raster C are extracted to obtain raster E. The maximum value of raster E is taken as the edge uplift height of the impact crater. The average edge uplift height of all impact craters at each degradation level is calculated at the study area diameter D scale. Taking the i-th degradation level as an example, its average edge uplift height has i The formula is as follows:

[0057]

[0058] Where h j This represents the edge uplift height of the j-th impact crater at the i-th degradation level.

[0059] The absolute age and average rim uplift height of impact craters at each degradation level have been calculated above. Therefore, the erosion rate Er(u,v) of any two degradation levels u and v is the difference in their average rim uplift heights divided by the difference in their absolute ages. The formulas for calculating the erosion rates are as follows:

[0060]

[0061] The unit of erosion rate is m / Myr. u The average edge uplift height of the impact crater, representing the uth degradation level, has v The average edge uplift height of the impact crater representing the vth degradation level.

[0062] The unit of erosion rate error is m / Myr. Compared with the depth-related degradation rate, the edge erosion rate of all impact craters is generally an order of magnitude lower in fresh impact crater class categories. The edge erosion rate of impact craters is generally less than the degradation rate, and the erosion rate gradually decreases with the increase of impact crater class.

[0063] Step 4: Generation of the degradation time sequence of impact crater morphology evolution.

[0064] Impact crater degradation sequence refers to the process of an impact crater from its formation to its complete disappearance under natural conditions, that is, it successively undergoes degradation processes from type 1 to type n. The time taken for the entire degradation process is the life cycle of the impact crater. Through the above steps, the absolute age of each degradation level of the impact crater and the degradation rate and erosion rate between two adjacent degradation levels can be obtained, namely Dr(1,2), Dr(2,3), ..., Dr(n-1,n); Er(1,2), Er(2,3), ..., Er(n-1,n).

[0065] If there is a lack of sufficient samples of relatively fresh Class 1 degradation impact craters in the study area, the degradation rate is calculated by subtracting the calculated average depth of the impact crater from the original impact crater depth (i.e., 0.2 times the impact crater diameter) and dividing by the age of the impact crater.

[0066]

[0067] D represents the diameter of the impact crater of the first degradation level.

[0068] The erosion rate was calculated by grouping all impact craters in the study area into groups with 10-meter diameter intervals. The result, h = c(D'), was obtained by least-squares fitting of the three impact craters with the largest edge heights in each diameter group. m The difference between the fitted edge height and the actual calculated edge height of a level 2 degradation impact crater is divided by the age of the impact crater.

[0069]

[0070] Where c and m are constants, D' is the diameter of the three impact craters with the largest edge height in each group, and h is the edge height of the impact crater in each diameter group.

[0071] By using the absolute age of each impact crater degradation level, and the corresponding impact crater erosion rate and degradation rate, nonlinear fitting was performed on Dr(1,2), Dr(2,3), ..., Dr(n-1,n); Er(1,2), Er(2,3), ..., Er(n-1,n) to obtain the impact crater degradation rate curve and impact crater erosion rate curve, respectively. This represents the ideal degradation time series of impact craters at the diameter D scale within the study area. The specific fitting formula is as follows:

[0072]

[0073]

[0074] Where A1, A2, b1, b2, C1, and C2 are the least squares fitting parameters, which are constants.

[0075] In this embodiment:

[0076] (1) Location of the landing area of ​​Tianwen-1

[0077] Tianwen-1 was launched in July 2020, successfully entered Mars orbit in February 2021, and landed on the southern part of Utopia Planitia on the Martian surface on May 15. The landing site is located at... Figure 1 The location of the "Zhurong" Mars rover is marked with a red five-pointed star. On May 22 of the same year, the "Zhurong" Mars rover safely drove off the landing platform and reached the surface of Mars to begin its exploration. Figure 1 The spatial distribution of impact crater levels, coded by hierarchical color, is shown within a study area of ​​approximately 134 square kilometers (HiRISE images ESP_069665_2055_RED and ESP_069876_2055_RED).

[0078] In this embodiment, the study area is selected from a 134-square-kilometer area around the "Zhurong" Mars rover. The resolution of the images obtained by the High Resolution Imaging Science Experiment Camera (HiRISE) is approximately 0.25 meters per pixel. This invention selects HiRISE images covering the study area to identify the original impact crater and classify its degree of degradation.

[0079] (2) Morphological characteristics and degradation level classification of impact craters in the study area

[0080] First, original impact craters with a diameter of 20 meters or more in the study area were identified and mapped. For example... Figure 1 As shown, the circles of different colors represent the identified impact craters. In this invention, a total of 2,625 impact craters were identified in the study area.

[0081] Then, through visual interpretation using ten descriptive factors and morphological features, the 2,625 identified impact craters were divided into seven degradation levels, including one Class 1 impact crater, 63 Class 2 impact craters, 123 Class 3 impact craters, 137 Class 4 impact craters, 225 Class 5 impact craters, 515 Class 6 impact craters, and 1,561 Class 7 impact craters.

[0082] (3) Dating of impact craters in the study area

[0083] The study area divides the impact crater into seven degradation levels.

[0084] Cumulative size frequency diagrams of impact craters at degradation levels 1-2, 1-3, 1-4, 1-5, 1-6, and 1-7 were constructed sequentially. Figure 2 ).like Figure 2 As shown, impact craters of degradation levels 1 to 2 are represented by red triangles, those of degradation levels 1 to 3 by orange squares, those of degradation levels 1 to 4 by yellow circles, those of degradation levels 1 to 5 by light blue triangles, those of degradation levels 1 to 6 by blue inverted triangles, and those of degradation levels 1 to 7 by dark blue pentagrams. Using pseudo-logarithms to group by diameter, the chronological functions of Hartmann and Neukum (2001) and the production function of Ivanov (2001) were plotted, with gray shaded areas representing chronological boundaries.

[0085] The age of impact craters was calculated using the cumulative distribution function and the impact crater production function, resulting in the model age of impact craters at each degradation level.

[0086] from Figure 1As can be seen, impact craters with a diameter greater than 100 m are parallel to the isochrones, and their distribution follows a predetermined impact crater production function, resulting in smaller errors in the observation data at this scale. Since the degradation severity levels of impact craters at the 100 m diameter scale are preserved, impact craters with diameters in the 100 m range are more representative of the study area. For the overall cumulative distribution age fitting of impact craters with diameters ≥ 100 m, a total of 267 impact craters with diameters ≥ 100 m participated in the dating. Among them, degradation level 1 to 2 (5 impact craters) is 72±30 Ma, degradation level 1 to 3 (35 impact craters) is 300±50 Ma, degradation level 1 to 4 (67 impact craters) is 420±50 Ma, degradation level 1 to 5 (117 impact craters) is 590±50 Ma, degradation level 1 to 6 (174 impact craters) is 720±50 Ma, and degradation level 1 to 7 (267 impact craters) is 920±60 Ma. The degradation for each degradation category is roughly between 100 Myr and 200 Myr.

[0087] (4) Calculation of degradation rate and erosion rate in the study area

[0088] By measuring the depth and uplift height of impact craters at different degradation levels identified in the study area, and combining this with the dating results of impact craters at each degradation level, the degradation rate and erosion rate between impact craters at each degradation level can be determined. Table 1 shows the depth and uplift height of impact craters with a diameter of 100 meters in the study area, and Table 2 shows the degradation rate and erosion rate of impact craters with a diameter of 100 meters in the study area.

[0089] Table 1 shows the average depth and average uplift edge height of impact craters with a diameter of 100 meters.

[0090]

[0091] Table 2 shows the degradation and erosion rates of impact craters with a diameter of 100 meters (except for degradation levels 1 and 2).

[0092]

[0093] Since the statistical number of Class 2 impact craters is very small, it is not possible to effectively constrain the time intervals between different categories. Therefore, this example uses the average depth data of impact craters from Class 3 to Class 7 to calculate the degradation rates Dr(3,4), Dr(4,5), Dr(5,6), and Dr(6,7) between different degradation levels. That is, from level 3 to level 4, Dr(3,4) = 0.018 m / Myr; from level 4 to level 5, Dr(4,5) = 0.004 m / Myr; from level 5 to level 6, Dr(5,6) = 0.005 m / Myr; from level 6 to level 7, Dr(6,7) = 0.003 m / Myr; the degradation rate from level 4 to level 7 is stable between 0.003 and 0.005 m / Myr; similarly, the erosion rates Er(3,4), Er(4,5), Er(5,6), and Er(6,7) from level 3 to level 7 are calculated using the average uplift edge height data of the impact crater for each degradation level from level 3 to level 7. Specifically, the degradation rate from level 3 to level 4 is Er(3,4) = 0.008 m / Myr; from level 4 to level 5 is Er(4,5) = 0.006 m / Myr; from level 5 to level 6 is Er(5,6) = 0.005 m / Myr; and from level 6 to level 7 is Er(6,7) = 0.003 m / Myr. The degradation rate and erosion rate gradually decrease with increasing impact crater level.

[0094] (5) Generation of degradation time-series curves in the study area

[0095] In this example, actual measurements of the first and second-order impact craters are missing. The degradation rates of relatively fresh first and second-order impact craters are determined by subtracting the actual impact crater depth from the original crater depth (0.2 times the diameter) and dividing by the crater's age. Fresh impact craters degrade rapidly in the early post-impact period, possibly at a rate of 0.2 m / Myr. The erosion rate of the impact craters was determined by grouping all impact craters in the study area at 10-meter diameter intervals and performing a least-squares fit on the three impact craters with the largest edge heights within each diameter, resulting in a fit of h = 0.232D. 0.710 The early erosion rate of the new impact crater can be approximately 0.03 m / Myr, calculated by dividing the difference in edge uplift height between the first and second-level impact craters by the crater age.

[0096] Using the degradation and erosion rates of fresh impact craters of levels 1 and 2 as described above, combined with the degradation and erosion rates of levels 3 to 7 in Table 2 and the absolute age of impact craters at each degradation level, the ideal degradation and erosion rates of impact craters with a diameter of 100 m in the study area were obtained by least-squares fitting of the degradation and erosion rates of each impact crater degradation level and their corresponding ages. The degradation rate curves and erosion rate curves are shown below (e.g., ...). Figure 3 As shown):

[0097]

[0098]

[0099] like Figure 3 The figure shows the ideal degradation rate and erosion rate curves based on the 100m diameter impact crater in the study area, where orange represents the degradation rate and blue represents the erosion rate.

[0100] This represents the ideal degradation time series of impact craters on a diameter scale (D) within the study area. It can be observed that fresh impact craters degrade rapidly in the early stages, with the degradation rate decreasing by two orders of magnitude over time before stabilizing. This may be due to a weakened ability to trap sediments and other infill materials in the later stages of degradation. The erosion rate of the impact craters in the later stages does not change significantly, possibly because the crater filling process reduces the erosive effect of wind and sand on the crater edges. With the decrease in the amount of movable sediment and the reduction in the slope of the impact crater walls, the erosion rate at the crater edges also decreases slowly. Both the edge erosion rate and the depth degradation rate decrease with increasing time scale.

[0101] Example 2

[0102] This embodiment discloses a Martian surface degradation and erosion rate analysis system based on impact crater classification.

[0103] like Figure 5 As shown, the Martian surface degradation and erosion rate analysis system based on impact crater classification includes:

[0104] The absolute dating module is configured to classify the degradation levels of impact craters within the study area and calculate the absolute age of each degradation level impact crater.

[0105] The impact crater degradation rate and erosion rate calculation module is configured to: calculate the average depth of all impact crater depths at each degradation level and the average edge uplift height of all impact crater edges at each degradation level under a set diameter scale; and calculate the impact crater degradation rate and impact crater erosion rate between any two degradation levels based on the absolute age of the impact crater at each degradation level.

[0106] The fitting module is configured to perform nonlinear fitting on the impact crater degradation rate and impact crater erosion rate between adjacent degradation levels to obtain the impact crater degradation rate curve and impact crater erosion rate curve.

[0107] Example 3

[0108] The purpose of this embodiment is to provide a computer-readable storage medium.

[0109] A computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps in the method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in Embodiment 1 of this disclosure.

[0110] Example 4

[0111] The purpose of this embodiment is to provide an electronic device.

[0112] An electronic device includes a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in Embodiment 1 of this disclosure.

[0113] The steps and methods involved in the apparatuses of Embodiments 2, 3, and 4 above correspond to those in Embodiment 1. For specific implementation details, please refer to the relevant description section of Embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood as including any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and enabling the processor to perform any of the methods in this invention.

[0114] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0115] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for analysis of Mars surface degradation and erosion rates based on crater counting, characterized in that, Includes the following steps: The impact craters in the study area were classified into degradation levels, and the absolute age of each degradation level impact crater was calculated. Calculate the average depth of all impact craters at each degradation level, and the average edge uplift of all impact crater edges at each degradation level, within a given diameter scale. Based on the absolute age of impact craters at each degradation level, calculate the impact crater degradation rate and impact crater erosion rate between any two degradation levels. The average depth of all impact craters at each degradation level is calculated using the following formula: in, d j Indicates the first i Degradation level j The depth of the impact crater; N i The number of impact craters within each degradation level; The impact crater degradation rate between any two degradation levels is calculated using the following formula: Dr ( u,v ) in, dave u Representing the u The average depth of impact craters of varying degradation levels dave v Representing the v The average depth of impact craters of varying degradation levels T u Representative of the research area u The absolute age of the impact crater of the class of degradation. T v Representative of the research area v The absolute age of the impact crater of the class of degradation; The average edge uplift height of all impact crater edge uplift heights for each degradation level is calculated using the following formula: in, h j Indicates the first i Degradation level j The edge of the impact crater rose in height; in, Er ( u,v The value represents the impact crater erosion rate between degradation levels u and v, expressed in m / Myr. have u Representing the u The average edge uplift height of impact craters of varying degradation levels. have v Representing the v The average edge uplift height of the impact crater of the degradation grade; Nonlinear fitting was performed on the impact crater degradation rate and impact crater erosion rate between adjacent degradation levels to obtain impact crater degradation rate curves and impact crater erosion rate curves.

2. The method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in claim 1, characterized in that: Based on morphology and degree of degradation, the impact craters in the study area were divided into... n Class of degradation level, i The degradation level, i =1, 2, ..., n Among them, Class 1 is the freshest impact crater, and Class n impact craters have the highest degree of degradation; Degradation levels 1 to 2, 1 to 3, ..., 1 to n The diameter-frequency distribution of impact craters of different degradation levels was used, and the absolute age of impact craters of each degradation level was determined by employing the cumulative distribution function and the impact crater production function.

3. The method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in claim 1, characterized in that, If there is a lack of sufficient samples of relatively fresh Class 1 degraded impact craters within the study area, then: The degradation rate is calculated as follows: Dr (1,2)= Dr (1,2) represents the impact crater degradation rate between degradation levels 1 and 2; D This represents the diameter of an impact crater of the first degradation level. dave 2 represents the first 2 The average depth of impact craters of varying degradation levels T 2 represents the research area. 2 The absolute age of the impact crater of the class of degradation; The erosion rate is calculated as follows: Er (1,2)= in, Er (1,2) represents the impact crater erosion rate between the first and second degradation levels; h =c( D’ ) m To group all impact craters in the study area according to a set diameter interval, the edge height results were obtained by performing least-squares fitting on multiple impact craters with the largest edge heights in each diameter group. c , m It is a constant. D’ The diameter of the three impact craters with the largest edge height in each group; have 2 represents the average edge uplift height of the impact crater in the second degradation level.

4. The method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in claim 1, characterized in that, The fitting formulas for the impact crater degradation rate and impact crater erosion rate between adjacent degradation levels are as follows: in, A 1 ，A 2 ，b 1 ，b 2 ，C 1 ，C 2 represents the least squares fitting parameters, which are constants.

5. The method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in claim 1, characterized in that, The degradation rate and erosion rate of impact craters gradually decrease as the degradation level of impact craters increases.

6. A Martian surface degradation and erosion rate analysis system based on impact crater classification, characterized in that: include: The absolute dating module is configured to classify the degradation levels of impact craters within the study area and calculate the absolute age of each degradation level impact crater. The impact crater degradation and erosion rate calculation module is configured to: calculate the average depth of all impact crater depths at each degradation level and the average edge uplift height of all impact crater edges at each degradation level, based on the absolute age of impact craters at each degradation level; calculate the impact crater degradation rate and impact crater erosion rate between any two degradation levels; the average depth of all impact crater depths at each degradation level is calculated using the following formula: in, d j Indicates the first i Degradation level j The depth of the impact crater; N i The number of impact craters within each degradation level; The impact crater degradation rate between any two degradation levels is calculated using the following formula: Dr ( u,v ) in, dave u Representing the u The average depth of impact craters of varying degradation levels dave v Representing the v The average depth of impact craters of varying degradation levels T u Representative of the research area u The absolute age of the impact crater of the class of degradation. T v Representative of the research area v The absolute age of the impact crater of the class of degradation; The average edge uplift height of all impact crater edge uplift heights for each degradation level is calculated using the following formula: in, h j Indicates the first i Degradation level j The edge of the impact crater rose in height; in, Er ( u,v The value represents the impact crater erosion rate between degradation levels u and v, expressed in m / Myr. have u Representing the u The average edge uplift height of impact craters of varying degradation levels. have v Representing the v The average edge uplift height of the impact crater of the degradation grade; The fitting module is configured to perform nonlinear fitting on the impact crater degradation rate and impact crater erosion rate between adjacent degradation levels to obtain the impact crater degradation rate curve and impact crater erosion rate curve.

7. A computer-readable storage medium having a program stored thereon, characterized in that, When executed by the processor, the program implements the steps in the method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in any one of claims 1-5.

8. An electronic device, comprising a memory, a processor, and a program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the method for analyzing Martian surface degradation and erosion rate based on impact crater classification as described in any one of claims 1-5.

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