Method, storage medium and system for calculating fault characteristic data

Abstract

The present invention provides a method, storage medium, and system for calculating fault characteristic data. The method comprises: obtaining horizontal and vertical coordinate data and survey area contour data for each point of the fault polygon; obtaining elevation data for each point of the fault polygon based on the horizontal and vertical coordinate data and survey area contour data; and calculating fault parameters based on the horizontal and vertical coordinate data and elevation data for each point of the fault polygon. The parameters include at least: maximum fault distance, fault extension length, fault strike, fault dip, and fault inclination. The present invention solves the problem of cumbersome human-computer interaction and time-consuming manual fault data statistics. The method for calculating fault characteristic data provided by the present invention enables rapid acquisition of fault parameters, thereby improving work efficiency.

Description

Technical Field

[0001] The present invention relates to the field of software, and in particular to a method, storage medium and system for calculating fault characteristic data. Background Art

[0002] The calculation of fault characteristic data is crucial in seismic tectonic interpretation. This involves obtaining the maximum fault throw, fault extension, fault strike, fault dip, and fault inclination angle based on existing contour data within the survey area and the horizontal and vertical coordinates of each point on the fault polygon. However, existing techniques involve tedious statistical work and require extensive manual repetition, necessitating urgent improvements. Summary of the Invention

[0003] To address these challenges, the present invention proposes a method, storage medium, and system for calculating fault characteristic data. These methods address the time-consuming and tedious human-computer interaction associated with manually collecting fault data. The method for calculating fault characteristic data provided by the present invention enables rapid acquisition of fault parameters, thereby improving work efficiency.

[0004] The present invention provides a method for calculating fault characteristic data, comprising:

[0005] Obtain the horizontal and vertical coordinate data of each point of the fault polygon and the contour line data of the survey area;

[0006] Obtain elevation data of each point on the fault polygon according to the horizontal and vertical coordinate data of each point on the fault polygon and the contour line data of the survey area;

[0007] The parameters of the fault are calculated based on the horizontal and vertical coordinate data and elevation data of each point of the fault polygon. The parameters include at least: maximum fault distance, fault extension length, fault strike, fault dip and fault inclination.

[0008] In addition, the elevation data of each point of the fault polygon is obtained based on the horizontal and vertical coordinate data of each point of the fault polygon and the contour data of the survey area, including:

[0009] Establish an interpolation file, and write fault data into the interpolation file. The fault data includes the horizontal and vertical coordinate data of each point of the fault polygon;

[0010] Establish the survey area contour grid file based on the survey area contour data;

[0011] Three-dimensional data is generated based on the interpolation file and the survey area contour grid file. The three-dimensional data includes horizontal and vertical coordinate data and elevation data.

[0012] In addition, the fault polygon is divided into two plates, the hanging plate and the footwall, along its horizontal axis. The first (n-1) / 2 points are located in the hanging plate, and the last (n-1) / 2 points are located in the footwall.

[0013] The intersection points of the horizontal axis and the two ends of the fault polygon are set as end A and end B respectively, and the entire plane is the XOY plane.

[0014] In addition, |Z k -Z n-k | is the fault distance between fault point k and point nk, where point k and point nk are located in the hanging wall and footwall respectively, Z k is the elevation data of point k, then the maximum fault distance L MAX for:

[0015] L MAX =max[|Z k -Z n-k |], (k=1, 2,..., n-1).

[0016] In addition, the calculation formula for the extension length of the fault is:

[0017] X i , Y i are the horizontal and vertical coordinates of the points on the fault polygon, and X is the extension length of the fault.

[0018] In addition, the process of determining the direction of the fault is as follows:

[0019] The coordinates of the fault A end are (X1, Y1, Z1), and the coordinates of the fault B end are (X m , Y m , Z m ), then the plane vector on the XOY plane is:

[0020]

[0021] Define the unit vector in the east direction Calculate the vector and The angle O;

[0022] The direction of the cross product of vector a and vector b is perpendicular to the plane in which the two vectors lie and obeys the right-hand rule, so:

[0023]

[0024] If Y1-Y m >0, exist The left direction, The angle with the east direction is O; if Y1-Y m <0, exist to the right, The angle with the east direction is 360°-O;

[0025] Finally, the fault strike is divided according to the different intervals to which O belongs in the XOY plane.

[0026] In addition, the process of calculating the dip of the fault is as follows:

[0027] Sum the X, Y, and Z values ​​of the upper and lower plate points respectively:

[0028]

[0029]

[0030] The strike vector of the known fault is:

[0031]

[0032] The dip is perpendicular to the strike, and the direction vector of the dip is:

[0033]

[0034] Known Then x(X m -X1)+y(Y m -Y1)=0, if x represents y:

[0035]

[0036] but When x is not zero, the direction vector of the inclination is:

[0037]

[0038] If x is represented by y, the direction vector of the inclination is:

[0039]

[0040] The direction vector of the inclination and the unit vector of the east direction The angle between them is the dip of the fault.

[0041] In addition, the maximum dip of the fault is calculated:

[0042] Known|Z k -Z n-k | is the fault distance between fault point k and point nk, (X k ,Y k ,Z k ) and (X n-k ,Y n-k ,Z n-k ) are the corresponding points on the hanging wall and footwall of the fault, and the tangent of the dip angle is the ratio of the fault throw here to the distance between the two points on the XOY plane:

[0043] θ is the inclination angle;

[0044] The inclination angles of all corresponding points are calculated, and the maximum value is the maximum inclination angle of the fault.

[0045] The present invention provides a storage medium storing computer instructions. When a computer executes the computer instructions, the storage medium is used to execute any one of the above methods for calculating fault characteristic data.

[0046] The present invention provides a system for computing fault feature data, comprising at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the processor, and the instructions are executed by the at least one processor to enable the at least one processor to:

[0047] Obtain the horizontal and vertical coordinate data of each point of the fault polygon and the contour line data of the survey area;

[0048] Obtain elevation data of each point on the fault polygon according to the horizontal and vertical coordinate data of each point on the fault polygon and the contour line data of the survey area;

[0049] The parameters of the fault are calculated based on the horizontal and vertical coordinate data and elevation data of each point of the fault polygon. The parameters include at least: maximum fault distance, fault extension length, fault strike, fault dip and fault inclination.

[0050] The present invention solves the problem of tedious human-computer interaction and time-consuming manual statistics of fault data. The method for calculating fault characteristic data provided by the present invention can quickly obtain fault parameters, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A flowchart of a method for calculating fault characteristic data provided by one embodiment of the present invention;

[0052] Figure 2 A flowchart of a method for calculating fault characteristic data provided by one embodiment of the present invention;

[0053] Figure 3 A method for calculating the elevation of each point on a fault polygon by interpolation calculation provided in one embodiment of the present invention;

[0054] Figure 4 An example of a slice data format provided for one embodiment of the present invention;

[0055] Figure 5 An example of the interpolated data format provided for one embodiment of the present invention;

[0056] Figure 6A fault strike division rule provided in one embodiment of the present invention;

[0057] Figure 7 A fault dip division rule provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0058] The present invention is further described in detail below with reference to specific embodiments and accompanying drawings, which are intended only to elaborate on the specific embodiments of the present invention and do not impose any limitation on the present invention. The scope of protection of the present invention shall be subject to the claims.

[0059] Reference Figure 1 The present invention proposes a method for calculating fault characteristic data, comprising:

[0060] Step S001, obtaining the horizontal and vertical coordinate data of each point of the fault polygon and the contour line data of the survey area;

[0061] Step S002, obtaining elevation data of each point of the fault polygon according to the horizontal and vertical coordinate data of each point of the fault polygon and the contour data of the survey area;

[0062] Step S003, calculating the fault parameters according to the horizontal and vertical coordinate data and elevation data of each point of the fault polygon, the parameters at least including: maximum fault throw, fault extension length, fault strike, fault dip and fault inclination.

[0063] Obtain the horizontal and vertical coordinate data of each point of the fault polygon and the contour line data of the survey area, the horizontal and vertical coordinate data (X, Y) of each point of the fault polygon and the contour line data (X, Y, Z) of the survey area, where Z is the elevation data.

[0064] Obtain elevation data Z based on the horizontal and vertical coordinate data (X, Y) and the survey area contour data (X, Y, Z).

[0065] After the three-axis coordinates on the coordinate system are obtained, the parameters of the fault are calculated based on them for subsequent research and practical use.

[0066] The present invention solves the problem of tedious human-computer interaction and time-consuming manual statistics of fault data. The method for calculating fault characteristic data provided by the present invention can quickly obtain fault parameters, thereby improving work efficiency.

[0067] In one embodiment, obtaining elevation data of each point on the fault polygon based on the horizontal and vertical coordinate data of each point on the fault polygon and the contour data of the survey area includes:

[0068] Establish an interpolation file, and write fault data into the interpolation file. The fault data includes the horizontal and vertical coordinate data of each point of the fault polygon;

[0069] Establish the survey area contour grid file based on the survey area contour data;

[0070] Three-dimensional data is generated based on the interpolation file and the contour grid file of the survey area. The three-dimensional data includes horizontal and vertical coordinate data and elevation data. Figure 2 :

[0071] Step S101: Import prodata. The prodata includes the horizontal and vertical coordinates of each point on the prodata polygon. The first and second columns of the prodata are the horizontal and vertical coordinates of each point on the prodata polygon, respectively. The fifth column is the name of the prodata polygon to which the point belongs.

[0072] Step S102: import the interpolated data. The first three columns of the data are the horizontal and vertical coordinates and elevation of each point on the fault polygon.

[0073] Step S103, calculation.

[0074] Step S104: Get the result and choose to save the data.

[0075] Figure 3 This is a flowchart for calculating the elevation of each point on the fault polygon, which specifically includes the following steps:

[0076] Step S201: Create an interpolation file. First, create a .bln file. Write the first two columns of data from the prodata file starting from the second row into the first and second columns. The first column of the first row of the .bln data is the number of rows in the prodata file, that is, the length from the second row to the end of the data. The second column of the first row is 0.

[0077] Step S202: Create a contour grid file for the survey area. Use the contour data of the survey area as a table (where the 1st, 2nd, and 3rd columns are the horizontal and vertical coordinate values ​​and elevations of each point in the survey area, respectively). Grid this table in Surfer. Click 'Data' in 'Grid' on the Surfer main page, select this file, and in the Grid Line Geometry Properties box, set the spacing in the x and y directions to 10, set X to 'Column A', Y to 'Column B', and Z to 'Column C'. Select 'Kriging Interpolation Method' and click OK to generate a Surfer grid file.

[0078] In step S203, import the Surfer interpolation calculation. Click 'Section' in 'Grid' on the Surfer main page. First, select the Surfer grid file created in step S202, and then select the .bln file created in step S201. Surfer will generate a table file.

[0079] Step S204, deleting all data after the third column in the table file obtained in S203, and this file is the data file.

[0080] Figure 4 It is the data format of prodata. The first and second columns are the horizontal and vertical coordinates of each point on the fault polygon, and the fifth column is the fault number to which this point belongs.

[0081] Figure 5 The data format is data. The first three columns are the horizontal, vertical coordinates and elevation of each point in the fault polygon.

[0082] In one embodiment, the fault polygon is divided into two plates, a hanging plate and a footwall, along the horizontal axis of the fault polygon, the first (n-1) / 2 points are located in the hanging plate, and the last (n-1) / 2 points are located in the footwall;

[0083] The intersection points of the horizontal axis and the two ends of the fault polygon are set as end A and end B respectively, and the entire plane is the XOY plane.

[0084] For the purpose of subsequent calculations and descriptions, the horizontal axis of the fault polygon is used to divide the fault polygon into two disks.

[0085] In one embodiment, |Z k -Z n-k | is the fault distance between fault point k and point nk, where point k and point nk are located in the hanging wall and footwall respectively, Z k is the elevation data of point k, then the maximum fault distance L MAX for:

[0086] L MAX =max[|Z k -Z n-k |], (k=1, 2,..., n-1).

[0087] Let the first point in the fault polygon data represent one end of the fault as end A, and the other end as end B, (X i , Y i , Z i )(i=1,2,...,n-1) are the coordinates of each point of a fault polygon. i=1 and i=n are the endpoints of fault A (the same point). That is, there are (n-1) / 2 points on each side of the fault. The first (n-1) / 2 points are from fault A to fault B, arranged in order. The last (n-1) / 2 points are from fault B to fault A, arranged in order. The last point is a repetition of the endpoint of A. Therefore, the corresponding point of the kth point on the other side is the nkth point. k -Z n-k | is the fault throw at this point, where the maximum value is the maximum fault throw of the fault:

[0088] L MAX =max[|Z k -Z n-k |]

[0089] (k=1, 2, ..., n-1)

[0090] In one embodiment, the calculation formula for the extended length of the fault is:

[0091] X i , Y i are the horizontal and vertical coordinates of the points on the fault polygon, and X is the extension length of the fault.

[0092] Calculate the plane distance between every two points in the fault polygon and sum them up. The extended length of the fault is half of the result.

[0093] In one embodiment, the process of determining the direction of the fault is as follows:

[0094] The coordinates of the fault A end are (X1, Y1, Z1), and the coordinates of the fault B end are (X m , Y m , Z m ), then the plane vector on the XOY plane is:

[0095]

[0096] Define the unit vector in the east direction Calculate the vector and The angle O;

[0097] The direction of the cross product of vector a and vector b is perpendicular to the plane in which the two vectors lie and obeys the right-hand rule, so:

[0098]

[0099] If Y1-Y m >0, exist The left direction, The angle with the east direction is O; if Y1-Y m <0, exist to the right, The angle with the east direction is 360°-O;

[0100] Finally, the fault strike is divided according to the different intervals to which O belongs in the XOY plane.

[0101] The coordinates of the fault A end are (X1, Y1, Z1), and the coordinates of the fault B end are (Xm , Y m , Z m ), then the plane vector on the XOY plane:

[0102]

[0103] In the actual data, the east direction of the survey area coincides with the X-axis direction of the coordinate system, and the unit vector in the east direction is defined as Calculate the vector and The angle O.

[0104] From the definition of curl, we know that the direction of the vector product of vector a and vector b is perpendicular to the plane in which the two vectors are located and obeys the right-hand rule, so:

[0105] If Y1-Y m >0, exist All left direction, The angle with the east direction is O; if Y1-Y m <0, exist All right direction, The angle with the east direction is 180°-O; then it is divided into different directions according to different angles, and the division rules are as follows Figure 6 As shown, when 0-30 degrees, it is NEE direction, 30-45 degrees is NE direction, 45-90 is NNE direction, and so on.

[0106] In one embodiment, the process of calculating the inclination of a fault is as follows:

[0107] Sum the X, Y, and Z values ​​of the upper and lower plate points respectively:

[0108]

[0109]

[0110] The strike vector of the known fault is:

[0111]

[0112] The dip is perpendicular to the strike, and the direction vector of the dip is:

[0113]

[0114] Known Then x(X m -X1)+y(Y m -V1)=0, if x represents y:

[0115]

[0116] but When x is not zero, the direction vector of the inclination is:

[0117]

[0118] If x is represented by y, the direction vector of the inclination is:

[0119]

[0120] The direction vector of the inclination and the unit vector of the east direction The angle between them is the dip of the fault.

[0121] Given that the calculated angle between the fault strike and the due east direction is 0, the first (-1) / 2 points are points on one plate of the fault polygon, and the next (-1) / 2 points are points on the other plate. The sum of the X, Y, and Z values ​​of each point on both plates is:

[0122]

[0123]

[0124] The vector of the known fault direction is:

[0125]

[0126] The dip is perpendicular to the strike, and the direction vector of the dip is:

[0127]

[0128] Known Then x(X m -X1)+y(Y m -Y1)=0, use x to represent y:

[0129]

[0130] but When x is not zero (the fault strike is not completely due east):

[0131]

[0132] It can be used as the direction vector of inclination, d = ±1.

[0133] The fault dip is the direction from the hanging wall to the footwall. The hanging wall of a normal fault has a lower elevation, while the footwall of a reverse fault has a lower elevation. Here, the direction from the higher elevation to the lower elevation is uniformly given as the dip. This direction is 180 degrees different from the direction of the normal fault and is the same as the reverse fault direction:

[0134] When ZZ1 > ZZ2, XX1 < XX2 or ZZ1 < ZZ2, XX1 > XX2:

[0135] The projection vector of the direction from the block with a higher fault elevation to the block with a lower elevation on the x-axis is greater than zero, so d = 1.

[0136] When ZZ1 > ZZ2, XX1 > XX2 or ZZ1 < ZZ2, XX1 < XX2: Similarly, d = -1.

[0137] Similarly, if y is used to represent x:

[0138]

[0139] y is not zero, and the fault strike is not exactly due north.

[0140] The direction from the block with a larger elevation to the block with a smaller elevation is uniformly given as the dip direction:

[0141] When ZZ1 > ZZ2, YY1 < YY2 or ZZ1 < ZZ2, YY1 > YY2: d = 1.

[0142] When ZZ1 > ZZ2, YY1 > YY2 or ZZ1 < ZZ2, YY1 < YY2: d = -1.

[0143] When d = 1, it is a reverse fault; when d = -1, it is a normal fault.

[0144] The vector representing the fault dip direction is obtained, the angle between the fault dip and the due east direction is obtained, and finally, it is divided into different dips according to different angles. The division rules are as Figure 7 shown, and all four quadrants of the coordinate axes are divided.

[0145] In one of the embodiments, the maximum dip angle of the fault is calculated:

[0146] It is known that |Z k -Z n-k | is the fault displacement between point k and point n - k of the fault, (X k , Y k , Z k ) and (X n-k , Y n-k , Z n-k ) are the corresponding points on the hanging wall and footwall of the fault respectively. The tangent value of the dip angle is the ratio of the fault displacement here to the distance between the two points on the XOY plane:

[0147] θ is the dip angle;

[0148] The dip angles of all corresponding points are calculated, and the maximum value is taken as the maximum dip angle of the fault.

[0149] It is also possible to calculate the average tilt angle from all tilt angles.

[0150] The present invention further provides a storage medium storing computer instructions. When a computer executes the computer instructions, the storage medium is used to execute any of the above methods for calculating fault characteristic data.

[0151] The present invention further provides a system for computing fault feature data, comprising at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the processor, and the instructions are executed by the at least one processor to enable the at least one processor to:

[0152] Obtain the horizontal and vertical coordinate data of each point of the fault polygon and the contour line data of the survey area;

[0153] Obtain elevation data of each point on the fault polygon according to the horizontal and vertical coordinate data of each point on the fault polygon and the contour line data of the survey area;

[0154] The parameters of the fault are calculated based on the horizontal and vertical coordinate data and elevation data of each point of the fault polygon. The parameters include at least: maximum fault distance, fault extension length, fault strike, fault dip and fault inclination.

[0155] The above description is only the principle and preferred embodiment of the present invention. It should be noted that for those skilled in the art, several other variations can be made based on the principle of the present invention, which should also be considered as the scope of protection of the present invention.

Claims

1. A method for calculating fault characteristic data, characterized in that: include: Obtain the horizontal and vertical coordinate data of each point of the fault polygon and the contour line data of the survey area; Obtain elevation data of each point on the fault polygon according to the horizontal and vertical coordinate data of each point on the fault polygon and the contour line data of the survey area; Calculating fault parameters based on horizontal and vertical coordinate data and elevation data of each point of the fault polygon, the parameters at least including: maximum fault throw, fault extension length, fault strike, fault dip and fault inclination; The elevation data of each point on the fault polygon is obtained based on the horizontal and vertical coordinate data of each point on the fault polygon and the contour data of the survey area, including: Establish an interpolation file, and write fault data into the interpolation file. The fault data includes the horizontal and vertical coordinate data of each point of the fault polygon; Establish the survey area contour grid file based on the survey area contour data; Generate three-dimensional data based on the interpolation file and the survey area contour grid file. The three-dimensional data includes horizontal and vertical coordinate data and elevation data. The fault polygon is divided into two plates along its horizontal axis, the hanging plate and the footplate. The first (n-1) / 2 points are located in the hanging plate, and the last (n-1) / 2 points are located in the footplate. The intersection points of the horizontal axis and the two ends of the fault polygon are set as end A and end B respectively, and the entire plane is the XOY plane; The process of determining the direction of the fault is as follows: The coordinates of the fault A end are (X1, Y1, Z1), and the coordinates of the fault B end are (X m , Y m , Z m ), then the plane vector on the XOY plane is: Define the unit vector in the east direction Calculate the vector and The angle o; The direction of the cross product of vector a and vector e is perpendicular to the plane in which these two vectors lie and obeys the right-hand rule, so: If Y1-Y m >0, exist The left direction, The angle between Y1 and due east is o; if Y1-Y m <0, exist to the right, The angle with the east direction is 360°-O; Finally, the fault strike is divided according to the different intervals to which o belongs in the XOY plane.

2. The method for calculating fault characteristic data according to claim 1, characterized in that: |Z k -Z n-k | is the fault distance between fault point k and point nk, where point k and point nk are located in the hanging wall and footwall respectively, Z k is the elevation data of point k, then the maximum fault distance L MAX for: L MAX =max[|Z k -WITH n-k |],(k=1,2,...,n-1)。 3. The method for calculating fault characteristic data according to claim 1, wherein: The calculation formula for the fault extension length is: X i ,Y i are the horizontal and vertical coordinates of the points on the fault polygon, and X is the extension length of the fault.

4. The method for calculating fault characteristic data according to claim 1, wherein: The process of calculating the dip of a fault is as follows: Sum the X, Y, and Z values ​​of the upper and lower plate points respectively: The strike vector of the known fault is: The dip is perpendicular to the strike, and the direction vector of the dip is: Known Then x(X m -X1)+y(Y m -Y1)=0, if x represents y: but When x is not zero, the direction vector of the inclination is: If x is represented by y, the direction vector of the inclination is: The direction vector of the inclination and the unit vector of the east direction The angle between them is the dip of the fault.

5. The method for calculating fault characteristic data according to claim 1, wherein: Calculate the maximum dip of the fault: Known|Z k -Z n-k | is the fault distance between fault point k and point nk, (X k , Y k , Z k ) and (X n-k ,Y n-k ,Z n-k ) are the corresponding points on the hanging wall and footwall of the fault, and the tangent of the dip angle is the ratio of the fault throw here to the distance between the two points on the XOY plane: θ is the inclination angle; The inclination angles of all corresponding points are calculated, and the maximum value is the maximum inclination angle of the fault.

6. A storage medium, characterized in that The storage medium stores computer instructions, and when a computer executes the computer instructions, it is used to execute the method for calculating tomographic characteristic data according to any one of claims 1 to 5.

7. A system for calculating fault characteristic data, characterized in that: The invention comprises at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the one processor, and the instructions are executed by the at least one processor to enable the at least one processor to: Obtain the horizontal and vertical coordinate data of each point of the fault polygon and the contour line data of the survey area; Obtain elevation data of each point on the fault polygon according to the horizontal and vertical coordinate data of each point on the fault polygon and the contour line data of the survey area; Calculating fault parameters based on horizontal and vertical coordinate data and elevation data of each point of the fault polygon, the parameters at least including: maximum fault throw, fault extension length, fault strike, fault dip and fault inclination; The elevation data of each point on the fault polygon is obtained based on the horizontal and vertical coordinate data of each point on the fault polygon and the contour data of the survey area, including: Establish an interpolation file, and write fault data into the interpolation file. The fault data includes the horizontal and vertical coordinate data of each point of the fault polygon; Establish the survey area contour grid file based on the survey area contour data; Generate three-dimensional data based on the interpolation file and the survey area contour grid file. The three-dimensional data includes horizontal and vertical coordinate data and elevation data. The fault polygon is divided into two plates along its horizontal axis, the hanging plate and the footplate. The first (n-1) / 2 points are located in the hanging plate, and the last (n-1) / 2 points are located in the footplate. The intersection points of the horizontal axis and the two ends of the fault polygon are set as end A and end B respectively, and the entire plane is the XOY plane; The process of determining the direction of the fault is as follows: The coordinates of the fault A end are (X1, Y1, Z1), and the coordinates of the fault B end are (X m ,Y m ,Z m ), then the plane vector on the XOY plane is: Define the unit vector in the east direction Calculate the vector and The angle O; The direction of the cross product of vector a and vector e is perpendicular to the plane in which these two vectors lie and obeys the right-hand rule, so: If Y1-Y m >0, exist The left direction, The angle between Y1 and due east is o; if Y1-Y m <0, exist to the right, The angle with the east direction is 360°-O; Finally, the fault strike is divided according to the different intervals to which o belongs in the XOY plane.

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