A method and device for automatically identifying dome structures

Abstract

The present invention discloses an automatic recognition method and device for dome structure, the method comprising the following steps: (1) extracting bedrock strata with a ring number ≤ 2 from the stratum data to be recognized, and storing them in a stratum set D; (2) sequentially obtaining the stratum boundary ring number, envelope rectangle and area of ​​each stratum in the stratum set D, and storing them in a set Index; (3) identifying strata with ring structures from the set Index, and storing them in a stratum set Dtemp; (4) deleting strata that do not meet the dome structure characteristics in the set Dtemp according to the length-to-area ratio characteristics of the strata; (5) deleting strata that do not meet the dome structure characteristics in the set Dtemp according to the long-to-short axis ratio characteristics and the area ratio characteristics of the strata; (6) storing strata that meet the dome structure characteristics in the set Dtemp in the dome set Domes according to the occurrence characteristics of the strata. The recognition result of the present invention is relatively accurate and the degree of automation is high.

Description

Technical Field

[0001] The invention relates to geographic information technology, and in particular to an automatic recognition method and device for a dome structure. Background Art

[0002] Dome structure is an equiaxed anticline fold, which is a rock deformation caused by the movement of the earth's interior. The aspect ratio of the dome structure is less than 3:1, the rock layers are inclined to a certain extent, and the stratum boundaries are closed. The geometric shape is similar to an inverted rice bowl. When eroded, the older strata are exposed one after another starting from the core of the dome structure. On the plane geological map, it is roughly manifested as a ring of several strata, that is, the overlying strata surround the underlying strata. The dome structure is a favorable oil storage structure. The rapid identification and extraction of dome structures based on geological maps not only has certain application value in many fields such as resource exploitation, urban planning, and engineering construction, but also has certain research significance in regional tectonic evolution analysis, geological environment evaluation, and geological disaster prediction. Summary of the invention

[0003] Purpose of the invention: In view of the problems existing in the prior art, the present invention provides a method and device for automatically identifying a dome structure.

[0004] Technical solution: The automatic recognition method of the vault structure of the present invention comprises the following steps:

[0005] (1) Extract bedrock strata with ring numbers ≤ 2 from the strata data to be identified and store them in the strata set D;

[0006] (2) Obtain the number of boundary rings, the enveloping rectangle and its area of ​​each stratum in the stratum set D in turn, store them in the set Index, and then sort the Index from large to small according to the area of ​​the enveloping rectangle;

[0007] (3) Identify the strata with ring structure from the set Index and store them in the strata set Dtemp;

[0008] (4) According to the length-to-area ratio characteristics of the strata, delete the strata in the set Dtemp that do not meet the dome structural characteristics;

[0009] (5) According to the characteristics of the major-minor axis ratio and the area ratio of the strata, the strata that do not conform to the dome structural characteristics in the set Dtemp are deleted;

[0010] (6) According to the occurrence characteristics of the strata, the strata in the set Dtemp that meet the dome structural characteristics are stored in the dome set Domes, and the remaining strata are stored in the horizontal structure set HorizontalStructure.

[0011] Furthermore, step (1) comprises:

[0012] (1-1) Read the stratigraphic data to be identified into the stratigraphic set D. The attributes of each stratigraphic record in the set include ID, age attribute, stratigraphic boundary ring number and stratigraphic category;

[0013] (1-2) Delete the strata with loose layer age attribute in the strata set D;

[0014] (1-3) Delete the strata whose strata category is intrusive rock in the strata set D;

[0015] (1-4) Delete the strata with strata boundary ring number greater than 2 in the strata set D, and finally obtain the strata set D = {d i |i=1,2,...,SN},d i is the i-th stratum in D, and SN is the number of strata.

[0016] Furthermore, step (2) includes:

[0017] (2-1) For each stratum d in set D i , get the sequence ID of the stratum i 、Num of stratum boundary rings i , and extract the envelope rectangle and area of ​​each stratum i , stored in the collection Index = {s i (ID i ,Num i ,xmax i ,xmin i ,ymax i ,ymin i ,Area i )|i=1,2,...,SN},where s i is the i-th stratum in the set Index, {xmax i , xmin i ,ymax i ,ymin i} means s i The maximum value of the abscissa, the minimum value of the abscissa, the maximum value of the ordinate, and the minimum value of the ordinate of the enveloping rectangle, SN is the number of strata in the set D;

[0018] (2-2) Reorder the set Index in descending order of the area of ​​the enveloping rectangle.

[0019] Furthermore, step (3) includes:

[0020] (3-1) Read any unread stratum s from the collection Index i ;

[0021] (3-2) Get s i Number of rings Num i , if the number of rings is 1, return to step (3-1); otherwise, execute step (3-3);

[0022] (3-3) Read another layer s that has not been read from the collection Index j , and j>i, calculate s according to the following formula i and j The MBR contains the relation R(s i ,s j ):

[0023]

[0024] (3-4) If R(s i ,s j )=0, then return to step (3-3); if R(s i ,s j )=1, judge S i The inner ring and S j Are the outer ring areas of s equal? ​​If not, return to step (3-3). If they are equal, replace s i Serial number ID i ,s j Serial number ID j Deposit into the stratum collection Dtemp;

[0025] (3-5) Return to step (3-1) until all strata in the set Index are traversed and the strata set Dtemp = {temp k |k=1,2,...,TN},temp k is the kth annular formation in Dtemp, and TN is the number of annular formations.

[0026] Further, step (4) includes:

[0027] (4-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations;

[0028] (4-2) Read any group of stratigraphic combinations with adjacent relationships;

[0029] (4-3) According to the following formula, calculate the length-to-area ratio k1 of each stratum in the group of strata: ID The length-to-area ratio k0 to the circle of equal area ID Multiples of k ID ;

[0030]

[0031] In the formula, Length ID Size ID are the outer perimeter and the completed area of ​​the corresponding stratum, respectively;

[0032] (4-4) According to the k of all strata in this group of strata ID value, calculate the k value of this group of strata ID The variance of the value;

[0033] (4-5) If the k of this group of strata ID If the variance of the values ​​is greater than the preset threshold K, it is determined that the group of strata does not belong to the dome structure and the group of strata is deleted from Dtemp;

[0034] (4-6) Repeat steps (4-2) to (4-5) until all stratigraphic combinations have been traversed.

[0035] Further, step (5) includes:

[0036] (5-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations;

[0037] (5-2) Read any group of stratigraphic combinations with adjacent relationships;

[0038] (5-3) Calculate the ratio of the major and minor axes x of the stratum with the largest area in this group of strata ID , if its value is greater than the preset threshold value X, it is determined that the group of strata does not belong to the dome structure, it is deleted from the set Dtemp, and step (5-5) is executed, otherwise step (5-4) is executed;

[0039] (5-4) Calculate the complementary area ratio P of any two adjacent strata in this group of strata ID , if its value is greater than the preset threshold value P, it is determined that the group of strata does not belong to the dome structure and is deleted from the set Dtemp;

[0040] (5-5) Repeat steps (5-2)-(5-4) until all stratigraphic combinations have been traversed.

[0041] Further, step (6) comprises:

[0042] (6-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations;

[0043] (6-2) Read any group of stratigraphic combinations with adjacent relationships;

[0044] (6-3) For each stratum in the group of strata, extract the dip information of all occurrence points contained in the stratum range, and calculate the average dip angle avgDipAngle of the stratum;

[0045] (6-4) If the average dip angle avgDipAngle of all strata in the group of strata is less than the preset threshold a, the group of strata is stored in Domes; otherwise, it is stored in the horizontal structure set HorizontalStructure;

[0046] (6-5) Repeat operations (6-2)-(6-4) until all stratigraphic combinations in the set Dtemp are traversed, and the dome set Domes = {dome1|1 = 1, 2, ..., DN} and the horizontal structure set HorizontalStructure = {hs v |v=1,2,...,DH}, dome1 represents the lth dome structure, DN is the number of dome structures, hs v represents the vth horizontal structure, and DH is the number of horizontal structures.

[0047] The automatic recognition device for the dome structure of the present invention comprises a processor and a computer program stored in a memory and executable on the processor, and the above method is implemented when the processor executes the program.

[0048] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: based on the morphological characteristics and spatial structural characteristics of the dome structure on the geological map, the present invention realizes the automatic recognition of the dome structure. The method has a good recognition effect and a high degree of automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is the regional geological map data of the embodiment;

[0050] Figure 2 is a flow chart of the automatic identification method of the vault structure provided by the present invention;

[0051] Figure 3 This is the result diagram after loose layer screening;

[0052] Figure 4 This is the result diagram after intrusive rock screening;

[0053] Figure 5 This is the result diagram after screening based on the number of rings;

[0054] Figure 6 This is the recognition result diagram after filtering the ring structure;

[0055] Figure 7 This is the recognition result diagram after screening based on the length-to-area ratio;

[0056] Figure 8 This is the identification result map after screening based on the ratio of the major and minor axes and the formation area ratio;

[0057] Fig. 9 It is the dome structure that is finally identified after screening based on its occurrence. DETAILED DESCRIPTION

[0058] The technical solution of the present invention is further described in detail below. In this embodiment, a 1:50,000 regional geological map of Nanjing City, Jiangsu Province is selected as experimental data ( Figure 1 ). The projection coordinate system used in the geological map is the 92 Nanjing local coordinate system. The following is further explained by describing a specific embodiment in conjunction with the accompanying drawings.

[0059] This embodiment provides a method for automatically identifying a dome structure. Figure 2 As shown, the specific steps include:

[0060] (1) Extract bedrock strata with ring numbers ≤ 2 from the stratum data to be identified and store them in the stratum set D.

[0061] This step specifically includes:

[0062] (1-1) Read the stratigraphic data to be identified into the stratigraphic set D. The attributes of each stratigraphic record in the set include ID, age attribute, stratigraphic boundary ring number and stratigraphic category;

[0063] (1-2) Delete the strata with loose layer age attribute in the strata set D (specifically, the elements with strata codes starting with Q); the results after screening are shown in Figure 3 ;

[0064] (1-3) Delete the strata whose strata are intrusive rocks in the strata set D; the results after screening are shown in Figure 4 ;

[0065] (1-4) Delete the strata with strata boundary ring number greater than 2 in the strata set D, and finally obtain the strata set D = {d i |i=1,2,...,SN},d i is the i-th stratum in D, SN is the number of strata, and its value in this embodiment is 5341. Figure 5 .

[0066] (2) The number of stratum boundary rings, the enveloping rectangle and its area of ​​each stratum in the stratum set D are obtained in turn, and stored in the set Index. Then, the Index is sorted from large to small according to the area of ​​the enveloping rectangle.

[0067] This step specifically includes:

[0068] (2-1) For each stratum d in set D i , get the sequence ID of the stratum i 、Num of stratum boundary rings i , and extract the envelope rectangle and area of ​​each stratum i , stored in the collection Index = {s i (ID i ,Num i ,xmax i ,xmin i ,ymax i ,ymin i ,Area i )|i=1,2,...,SN},where s i is the i-th stratum in the set Index, {xmax i ,xmin i ,ymax i ,ymin i} means s i The maximum value of the abscissa, the minimum value of the abscissa, the maximum value of the ordinate, and the minimum value of the ordinate of the enveloping rectangle, SN is the number of strata in the set D;

[0069] (2-2) Reorder the set Index in descending order of the area of ​​the enveloping rectangle.

[0070] (3) Identify the strata with a ring structure from the set Index and store them in the strata set Dtemp.

[0071] This step specifically includes:

[0072] (3-1) Read any unread stratum s from the collection Index i ;

[0073] (3-2) Get s i Number of rings Num i , if the number of rings is 1, return to step (3-1); otherwise, execute step (3-3);

[0074] (3-3) Read another layer s that has not been read from the collection Index j , and j>i, calculate s according to the following formula i and j The MBR contains the relation R(s i ,s j ):

[0075]

[0076] (3-4) If R(s i,s j )=0, then return to step (3-3); if R(s i ,s j )=1, judge S i The inner ring and S j Are the outer ring areas of s equal? ​​If not, return to step (3-3). If they are equal, replace s i Serial number ID i ,s i Serial number ID j Deposit into the stratum collection Dtemp;

[0077] (3-5) Return to step (3-1) until all strata in the set Index are traversed and the strata set Dtemp = {temp k |k=1,2,...,TN},temp k is the kth annular formation in Dtemp, TN is the number of annular formations, and its value is 59 in this embodiment. The formation set Dtemp result is shown in Figure 6 .

[0078] (4) According to the length-to-area ratio characteristics of the strata, the strata in the set Dtemp that do not conform to the dome structural characteristics are deleted.

[0079] This step specifically includes:

[0080] (4-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations;

[0081] (4-2) Read any group of stratigraphic combinations with adjacent relationships;

[0082] (4-3) According to the following formula, calculate the length-to-area ratio k1 of each stratum in the group of strata: ID The length-to-area ratio k0 to the circle of equal area ID Multiples of k ID ;

[0083]

[0084] In the formula, Length ID Size ID are the outer perimeter and the completed area of ​​the corresponding stratum, respectively;

[0085] (4-4) According to the k of all strata in this group of strata ID value, calculate the k value of this group of strata ID The variance of the value;

[0086] (4-5) If the k of this group of strata IDIf the variance of the values ​​is greater than a preset threshold value K, which is 0.1 in this embodiment, it is determined that the group of strata does not belong to the dome structure and the group of strata is deleted from Dtemp;

[0087] (4-6) Repeat steps (4-2) to (4-5) until all stratum combinations are traversed. The result of Dtemp is shown in Figure 7 .

[0088] (5) According to the characteristics of the major-minor axis ratio and the area ratio of the strata, the strata in the set Dtemp that do not conform to the dome structural characteristics are deleted.

[0089] This step specifically includes:

[0090] (5-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations;

[0091] (5-2) Read any group of stratigraphic combinations with adjacent relationships;

[0092] (5-3) Calculate the ratio of the major and minor axes x of the stratum with the largest area in this group of strata ID , if its value is greater than the preset threshold value X, which is 3 in this embodiment, it is determined that the group of strata does not belong to the dome structure, and it is deleted from the set Dtemp, and step (5-5) is executed, otherwise step (5-4) is executed;

[0093] (5-4) Calculate the complementary area ratio P of any two adjacent strata in this group of strata ID , if its value is greater than a preset threshold value P, which is 5 in this embodiment, it is determined that the group of strata does not belong to the dome structure and is deleted from the set Dtemp;

[0094] (5-5) Repeat steps (5-2) to (5-4) until all stratum combinations are traversed. The result of Dtemp is shown in Figure 8 .

[0095] (6) According to the occurrence characteristics of the strata, the strata in the set Dtemp that meet the dome structural characteristics are stored in the dome set Domes, and the remaining strata are stored in the horizontal structure set HorizontalStrucmre.

[0096] This step specifically includes:

[0097] (6-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations;

[0098] (6-2) Read any group of stratigraphic combinations with adjacent relationships;

[0099] (6-3) For each stratum in the group of strata, extract the dip information of all occurrence points contained in the stratum range, and calculate the average dip angle avgDipAngle of the stratum, specifically the average value of all dip angles;

[0100] (6-4) If the average dip angles avgDipAngle of all strata in the group of strata are less than a preset threshold a, in this embodiment, the threshold a is set to 5°, then the group of strata is stored in Domes; otherwise, it is stored in the horizontal structure set HorizontalStructure;

[0101] (6-5) Repeat operations (6-2) to (6-4) until all stratum combinations in the set Dtemp are traversed, and the dome set Domes = {dome l |l=1,2,...,DN} and HorizontalStructure={hs v |v=1,2,...,DH},dome l represents the first dome structure, DN is the number of dome structures, and its value in this embodiment is 11, hs v represents the vth horizontal structure, and DH is the number of horizontal structures. The final recognition result is shown in Fig. 9 .

[0102] After verification by experts, 3 of the 4 dome structures identified were correct and 1 was wrong. The reason for the error was that the stratigraphic coding in the original data was wrong. This embodiment shows that the method can meet the work needs of automatic identification of dome structures in practical applications.

[0103] This method can also be applied to the identification of horizontal structures. Horizontal structural landforms refer to landforms in which the layers of original sedimentary strata remain or are close to horizontal and have no fold changes under the vertical movement of the earth's crust. The inclination of the rock strata is usually less than or equal to 5°. Structural square mountains and structural stone pillars belong to horizontal structures. They are a type of discretely distributed mountain formed by the continuous erosion of soft and hard original sedimentary strata. The stratigraphic boundaries of structural square mountains and structural stone pillars are also in the form of mutually contained rings. On the plane geological map, their morphology is similar to that of dome structures, but the stratigraphic occurrence is different. This method is based on the ring inclusion feature and is suitable for the identification of these two types of horizontal structures.

[0104] This embodiment also provides an automatic recognition device for a dome structure, comprising a processor and a computer program stored in a memory and executable on the processor, wherein the processor implements the above method when executing the program.

[0105] The above disclosure is only a preferred embodiment of the present invention, which cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for automatically identifying a dome structure, comprising the following steps: (1) Extract bedrock strata with ring numbers ≤ 2 from the strata data to be identified and store them in the strata set D; (2) Obtain the number of boundary rings, the enveloping rectangle and the area of ​​each stratum in the stratum set D in turn, and store them in the set Index. Then sort all the strata in Index from large to small according to the area of ​​the enveloping rectangle. (3) Identify the strata with ring structure from the set Index and store them in the strata set Dtemp; (4) According to the length-to-area ratio characteristics of the strata, delete the strata in the set Dtemp that do not meet the dome structural characteristics; (5) According to the characteristics of the major-minor axis ratio and the area ratio of the strata, the strata that do not conform to the dome structural characteristics in the set Dtemp are deleted; (6) According to the occurrence characteristics of the strata, the strata in the set Dtemp that meet the dome structural characteristics are stored in the dome set Domes, and the remaining strata are stored in the horizontal structure set HorizontalStructure; in, Step (2) specifically includes: (2-1) For each stratum d in set D i , get the sequence ID of the stratum i 、Num of stratum boundary rings i , and extract the envelope rectangle and area of ​​each stratum i , stored in the collection Index = {s i (ID i ,Num i ,xmax i ,xmin i ,ymax i ,ymin i ,Area i )|i=1,2,…,SN}, where s i is the i-th stratum in the set Index, {xmax i ,xmin i ,ymax i ,ymin i } means s i The maximum value of the abscissa, the minimum value of the abscissa, the maximum value of the ordinate, and the minimum value of the ordinate of the enveloping rectangle, SN is the number of strata in the set D; (2-2) Rearrange all strata in the set Index according to the area of ​​the enveloping rectangle from large to small.

2. The method for automatically identifying a vault structure according to claim 1, characterized in that: Step (1) comprises: (1-1) Read the stratigraphic data to be identified into the stratigraphic set D. The attributes of each stratigraphic record in the set include ID, age attribute, stratigraphic boundary ring number and stratigraphic category; (1-2) Delete the strata with loose layer age attribute in the strata set D; (1-3) Delete the strata whose strata category is intrusive rock in the strata set D; (1-4) Delete the strata with the number of strata boundary rings > 2 in the strata set D, and finally obtain the strata set D = {d i |i=1,2,…,SN},d i is the i-th stratum in D, and SN is the number of strata.

3. The automatic identification method of the vault structure according to claim 1, characterized in that: Step (3) includes: (3-1) Read any unread stratum s from the collection Index i ; (3-2) Get s i The number of stratum boundary rings Num i , if the number of rings is 1, return to step (3-1); otherwise, execute step (3-3); (3-3) Read another layer s that has not been read from the collection Index j , and j>i, calculate s according to the following formula i and j The MBR contains the relation R(s i ,s j ): (3-4) If R(s i ,s j )=0, then return to step (3-3); if R(s i ,s j )=1, judge S i The inner ring and S j Are the outer ring areas of s equal? ​​If not, return to step (3-3). If they are equal, replace s i Serial number ID i ,s j Serial number ID j Deposit into the stratum collection Dtemp; (3-5) Return to step (3-1) until all strata in the set Index are traversed and the strata set Dtemp = {temp k |k=1,2,…,TN},temp k is the kth annular formation in Dtemp, and TN is the number of annular formations.

4. The automatic identification method of the vault structure according to claim 1, characterized in that: Step (4) comprises: (4-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations; (4-2) Read any group of stratigraphic combinations with adjacent relationships; (4-3) According to the following formula, calculate the length-to-area ratio k1 of each stratum in the group of strata: ID The length-to-area ratio k0 to the circle of equal area ID Multiples of k ID ; In the formula, Length ID Size ID are the outer perimeter and the completed area of ​​the corresponding stratum, respectively; (4-4) According to the k of all strata in this group of strata ID value, calculate the k value of this group of strata ID The variance of the values; (4-5) If the k of this group of strata ID If the variance of the values ​​is greater than the preset threshold K, it is determined that the group of strata does not belong to the dome structure and the group of strata is deleted from Dtemp; (4-6) Repeat steps (4-2) to (4-5) until all stratigraphic combinations have been traversed.

5. The automatic identification method of the vault structure according to claim 1, characterized in that: Step (5) comprises: (5-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations; (5-2) Read any group of stratigraphic combinations with adjacent relationships; (5-3) Calculate the ratio of the major and minor axes x of the stratum with the largest area in this group of strata ID , if its value is greater than the preset threshold value X, it is determined that the group of strata does not belong to the dome structure, it is deleted from the set Dtemp, and step (5-5) is executed, otherwise step (5-4) is executed; (5-4) Calculate the complementary area ratio p of any two adjacent strata in the group of strata ID , if its value is greater than the preset threshold value P, it is determined that the group of strata does not belong to the dome structure and is deleted from the set Dtemp; (5-5) Repeat steps (5-2)-(5-4) until all stratigraphic combinations have been traversed.

6. The automatic identification method of the vault structure according to claim 1, characterized in that: Step (6) comprises: (6-1) Divide the strata with adjacency relationship in the set Dtemp into a group to obtain several groups of strata combinations; (6-2) Read any group of stratigraphic combinations with adjacent relationships; (6-3) For each stratum in the group of strata, extract the dip information of all occurrence points contained in the stratum range, and calculate the average dip angle avgDipAngle of the stratum; (6-4) If the average dip angle avgDipAngle of all strata in the group of strata is less than the preset threshold a, the group of strata is stored in Domes; otherwise, it is stored in the horizontal structure set HorizontalStructure; (6-5) Repeat operations (6-2) to (6-4) until all stratum combinations in the set Dtemp are traversed, and the dome set Domes = {dome l |l=1,2,…,DN} and HorizontalStructure={hs v |v=1,2,…,DH},dome l represents the lth dome structure, DN is the number of dome structures, hs v represents the vth horizontal structure, and DH is the number of horizontal structures.

7. An automatic recognition device for a dome structure, comprising a processor and a computer program stored in a memory and executable on the processor, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 6 is implemented.

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