CN112734926B - Automatic generation method of geological profiles in loose layer covered areas - Google Patents

Abstract

The invention discloses an automatic generation method of a cut geological section facing to a loose layer coverage area, which comprises the following steps: (1) Loading a bedrock geological map, a regional geological map, section line data, DEM data and drilling data, and extracting geological boundary information data; (2) obtaining the intersection points of the section lines and all geological boundary lines; (3) Generating a bedrock map cutting section based on the bedrock geological map and the DEM; (4) Extracting a loose layer section line set based on the regional geological map; (5) Dividing the loose layer section line set into different groups based on stratum continuous relation; (6) acquiring the information of the burial depth of the adjacent borehole; (7) Generating a loose layer inferred bottom line of each layer, and constructing a loose layer profile; (8) And merging and constructing the cut geological section covered by the loose layer based on the loose layer section and the bedrock cut section. The method can effectively improve the modeling quality of the cut geological section and lay a good data foundation for three-dimensional modeling based on the sequence cut geological section.

Description

Automatic generation method of geological profiles in loose layer covered areas

Technical Field

The invention relates to the fields of geographic information and geology, and in particular to a method for automatically generating a geological profile cut in a loose layer covered area.

Background technique

The loose layer is a Quaternary and Neogene stratum composed of soil, sand, gravel, and pebble layers. The loose layer belongs to the overlying rock layer. The key lies in its loose medium characteristics, and its strength is far less than that of ordinary rock layers. A cut geological profile is a geological profile drawn by projection method in a certain direction on a geological map according to various geological and geographical elements and a certain scale. In the area covered by the loose layer, since its loose layer distribution information and bottom bedrock information come from the regional geological map and the bedrock geological map respectively, its cut geological profile generation method is relatively complicated, and the traditional cut geological profile generation method is difficult to directly apply.

Therefore, based on the stratigraphic distribution law of loose layers, the loose layers are constructed and the bedrock strata covered by the loose layers are reasonably inferred and modeled, and research on the automatic construction method of geological profiles in areas covered by loose layers is carried out, which has important research significance and practical value.

Summary of the invention

Purpose of the invention: In view of the problems existing in the prior art, the present invention provides a method for automatically generating a geological profile with high modeling quality for areas covered by loose layers.

Technical solution: The method for automatically generating a geological profile cut in a loose layer covered area according to the present invention comprises:

(1) Based on the regional geological map, DEM, borehole data and bedrock geological map of the study area, a set of regional geological boundaries GeoLine, a set of regional stratigraphic layers GeoPolygon, a set of bedrock geological boundaries BedrockLine, a set of bedrock stratigraphic layers BedrockPolygon, a set of borehole data Drills and a set of raster data GeoDEM are formed;

(2) Obtain the intersection points of the section line SL of the study area with each geological boundary line in the set BedrockLine and the set GeoLine, respectively, to form the bedrock surface intersection point set PA and the regional stratigraphic surface intersection point set PB;

(3) The bedrock surface intersection point set PA is used to segment the profile line SL to obtain the segment set SeLine. Then, the bedrock stratigraphic layer set BedrockPolygon and the raster data set GeoDEM are combined to extract the stratigraphic code set MK and the occurrence set AT on the profile line SL, and generate the bedrock geological profile SP and the surface line SurfaceLine.

(4) Use the regional stratigraphic surface intersection point set PB to segment the section line SL, obtain the segment set SbLine sorted from small to large, and then combine it with the regional stratigraphic surface set GeoPolygon to extract the loose layer section line set FL and the loose layer stratigraphic code set QC;

(5) Based on the formation continuity relationship, the loose layer section line set FL is divided into different groups and stored in the loose layer section line grouping set FG;

(6) Read any loose layer profile group fg _v from the set FG, obtain its adjacent drill hole drill from the drill hole set Drills, and obtain the loose layer thickness set DH of the group fg _v based on the loose layer stratigraphic code set QC;

(7) Based on the loose layer thickness set DH and the surface line SurfaceLine, the bottom lines of each loose layer are generated, and the loose layer profile is constructed and stored in the loose layer profile set QP;

(8) Execute steps (6)-(7) repeatedly until the set FG is traversed and all loose layer profiles are constructed;

(9) Based on all loose layer section geometries QP and bedrock cut geological sections SP, the cut geological sections of the loose layer covered area are constructed.

Furthermore, step (1) specifically includes:

(1-1) Extracting regional geological boundary data and regional stratigraphic layer data from the regional geological map of the study area, and storing them in the regional geological boundary set GeoLine and the regional stratigraphic layer set GeoPolygon respectively;

(1-2) Extracting bedrock geological boundary data and bedrock stratigraphic layer data from the bedrock geological map of the study area, and storing them in a bedrock geological boundary set BedrockLine and a bedrock stratigraphic layer set BedrockPolygon respectively. The bedrock stratigraphic layer data includes the stratigraphic unique number GID of the bedrock stratigraphic layer and the corresponding stratigraphic code;

(1-3) Store the drilling data of the study area into the drilling data set Drills;

(1-4) Extract raster data from the DEM of the study area and store it in the raster data set GeoDEM.

Furthermore, step (2) specifically includes:

(2-1) extracting the intersection point between the profile line SL and each bedrock geological boundary in the bedrock geological boundary set BedrockLine as the bedrock surface intersection point;

(2-2) The formation occurrence information of each bedrock surface intersection point is taken as the attribute of the point and stored in the bedrock surface intersection point set PA = {pa _i |i = 1, 2, ..., PI}, where pa _i represents the i-th bedrock surface intersection point and PI represents the number of bedrock surface intersection points;

(2-3) extracting the intersection points of the profile line SL and each regional geological boundary in the regional geological boundary set GeoLine as the regional stratigraphic surface intersection points;

(2-4) The stratigraphic occurrence information of each regional stratigraphic plane intersection is used as the attribute of the intersection and stored in the regional stratigraphic plane intersection set PB = {pb _j | j = 1, 2, ..., PJ}, where pb _j represents the jth regional stratigraphic plane intersection and PJ represents the number of regional stratigraphic plane intersections.

Furthermore, step (3) specifically includes:

(3-1) The formation attitude information of all points in the bedrock surface intersection set PA is stored in the attitude set AT = {α _i (ρ, θ, δ)|i = 1, 2, ..., PI}, where α _i (ρ, θ, δ) represents the formation attitude of the i-th bedrock surface intersection point, ρ is the formation dip, θ is the formation dip angle, δ is the formation strike, and PI represents the number of bedrock surface intersection points;

(3-2) Use the points in the bedrock surface intersection point set PA to split the profile line SL into PI segment lines and store them in the profile segment line set SeLine;

(3-3) Get the first endpoint of each segment line in the profile segment line set SeLine, store the unique stratigraphic number GID of the bedrock stratigraphic layer where the first endpoint is located as the attribute of the corresponding segment line, and establish the association between BedrockPolygon and SeLine;

(3-4) For each segment line in SeLine, find the stratigraphic code of the corresponding bedrock stratigraphic layer in BedrockPolygon according to its attribute GID, and store it in the stratigraphic code set MK = {mk _i |i = 1, 2, ..., PI}, where mk _i represents the stratigraphic code of the i-th segment line;

(3-5) Based on the bedrock surface intersection point set PA, the occurrence set AT and the raster data set GeoDEM, the bedrock geological profile SP and the surface line SurfaceLine are generated.

Furthermore, step (4) specifically includes:

(4-1) According to the geological map legend of the study area, establish a loose layer cover stratum code table PC from new to old;

(4-2) Use the points in the regional ground plane intersection point set PB to split the profile line SL into several segment lines and store them in the profile segment line set SbLine’;

(4-3) Obtain the first endpoints of all line segments in the section line segment set SbLine’, sort the line segments in ascending order according to the horizontal coordinates of the first endpoints, and obtain the section segment line set SbLine in an orderly arrangement;

(4-4) For each segment line in the profile segment line set SbLine, the unique stratigraphic number GID of the bedrock stratigraphic layer where its first and last endpoints are located is stored as its attribute, and an association is established between BedrockPolygon and SbLine;

(4-5) Get any segmented line in SbLine, and find the stratigraphic code of the corresponding regional stratigraphic layer in GeoPolygon according to its attribute GID;

(4-6) If the stratigraphic code of the segmentation line belongs to the loose layer cover stratigraphic code table PC, the stratigraphic code is stored in the loose layer stratigraphic code set QC, and the segmentation line is stored in the loose layer section line set FL;

(4-7) Loop through steps (4-5)-(4-6) until the set SbLine is traversed and the complete sets FL and QC are obtained.

Furthermore, step (5) specifically includes:

(5-1) According to the attribute GID of all segment lines in the segment line set SbLine, obtain the GID of each loose layer profile line in the loose layer profile line set FL;

(5-2) Based on the GID of the loose layer profile lines in the set FL, determine whether any two loose layer profile lines are continuous according to the following rules: if the GID difference between the two lines is 1, the two lines are determined to be continuous; otherwise, the two lines are determined to be discontinuous;

(5-3) All continuous loose layer profile lines are divided into a group and stored in the loose layer profile line grouping set FG = {fg _v |v = 1,2,...,vn}, where fg _v represents the vth loose layer profile line group, vn represents the number of groups, fg _v = {sg _v,w |w = 1,2,...,wn}, sg _v,w represents the wth loose layer profile line in the vth group, and wn represents the number of loose layer profile lines in the vth group.

Furthermore, step (6) specifically includes:

(6-1) Read any group of loose layer profile line groups fg _v in the loose layer profile line group set FG;

(6-2) Merge all the loose layer section lines in group fg _v to obtain a complete and continuous section line ft;

(6-3) According to the drill hole set Drills, obtain the neighboring drill hole drill that is closest to the section line ft;

(6-4) According to the loose layer stratum code set QC, the different loose layer strata in the group fg _v are obtained according to the relationship between the age of the strata;

(6-5) Read the thickness and lithology information of each layer in the adjacent drill hole, and according to the loose layer lithology classification in the regional geological map legend, integrate the thickness of each layer and store it in the loose layer thickness set DH = {dh(dc _o , _ho ) _o |o = 1,2,…,on}, where dc _o represents the oth loose layer layer, _ho represents the thickness of the oth loose layer layer, and on represents the number of loose layer layers.

Furthermore, step (7) specifically includes:

(7-1) Calculate the point drillPoint where the drill hole is projected onto the section line SL, convert it into a two-dimensional coordinate system, and obtain the horizontal and vertical coordinates (x _dp , y _dp ) of the point drillPoint;

(7-2) According to the loose layer thickness set DH, the lowest depth of each loose layer is obtained according to dh _o =y _{dp -ho} , and stored in the loose layer lowest depth set HP = {hp(dc _o , dh _o ) _o |o = 1, 2, ..., on}, where dc _o represents the oth loose layer, dh _o represents the lowest depth point of dc _o , and _ho represents the thickness of dc _o ;

(7-3) Read any stratum dc _o from the loose layer minimum depth set HP, extract the loose layer section lines with loose layer stratum code age less than or equal to dc _o from the group fg _v , and merge them into a section line fb;

(7-4) Get the two end points sp and ep of the profile line fb under the two-dimensional coordinates, and according to the lowest depth point dh _o of dc _o , get the bottom line of the loose layer stratum, and store it in the bottom line set QLine of the loose layer stratum;

(7-5) Loop through steps (7-3)-(7-4) until HP is completely traversed;

(7-6) Based on the surface line SurfaceLine and the loose layer bottom line set QLine, a surface element is constructed to generate a loose layer profile and store it in the loose layer profile set QP.

Further, step (7-4) specifically includes:

(7-4-1) Get the two end points sp and ep of the cross section line fb under the two-dimensional coordinates, and draw two perpendicular lines through the end points sp and ep;

(7-4-2) Read the lowest depth point dh _o of the formation dc _o , and draw a horizontal line that intersects the two vertical lines at points a _o and b _o ;

(7-4-3) Using the Bezier curve equation, generate two smooth curves between the three points sp, a _o , _dho and between the three points ep, b _o , _dho ;

(7-4-4) Merge the two curves as the bottom line of the loose layer stratum and store them in the loose layer stratum bottom line set QLine.

Furthermore, step (9) specifically includes:

(9-1) Assigning stratigraphic codes to the bedrock geological profile SP in sequence along the profile direction;

(9-2) Along the stratigraphic sequence, the stratigraphic codes are assigned to the loose layer section set QP in turn;

(9-3) The bedrock geological profile SP and the loose layer profile set QP are combined to obtain the geological profile of the loose layer covered area.

In the present invention, when bedrock geological map data is missing, bedrock stratum related information of the loose layer covered area can be obtained by the following method:

(1) Information on the occurrence of exposed bedrock strata and the surface intersection of strata and profile lines, obtained from regional geological maps;

(2) Inference of the location information of the bedrock strata in the area covered by the loose layer. If the exposed bedrock strata on the left and right ends of the loose layer are the same, it is inferred that the bedrock strata in the covered area are the same as the bedrock strata on the left and right ends; if the exposed bedrock strata on the left and right ends are different, the 1/2 point is taken as the dividing point between the two bedrock strata.

Beneficial effect: Compared with the prior art, the present invention has the following significant advantages: the present invention provides a method for automatically generating a cut geological profile in an area covered by a loose layer, which can effectively improve the modeling quality of the cut geological profile and lay a good data foundation for three-dimensional modeling based on sequence cut geological profiles.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a cross-section line, a regional geological map, and bedrock geological map data used in this embodiment;

FIG. 2 is the DEM data and drilling data used in this embodiment;

FIG3 is a flow chart of an embodiment of the present invention;

FIG4 is a bedrock geological profile generated in this embodiment;

FIG5 is a loose layer generated in this embodiment;

FIG6 is a cut geological section of loose layer cover generated in this embodiment;

FIG. 7 is a hand-drawn cut geological section in this embodiment.

Detailed ways

The technical solution of the present invention is further described in detail below. In this embodiment, a 1:5 Wanning Town mountain area geological map, a 1:100,000 Nanjing bedrock geological map, a 30m resolution Nanjing DEM data and a Nanjing borehole are selected as experimental data, as shown in Figures 1 and 2, and the section line is drawn from Nanjing Zijin Mountain to Qinglong Mountain. The following is further described by combining the accompanying drawings and describing a specific embodiment.

As shown in FIG3 , this embodiment provides a method for automatically generating a geological profile of a loose layer covered area, including:

(1) Based on the regional geological map, DEM, borehole data and bedrock geological map of the study area, a set of regional geological boundaries GeoLine, a set of regional stratigraphic layers GeoPolygon, a set of bedrock geological boundaries BedrockLine, a set of bedrock stratigraphic layers BedrockPolygon, a set of borehole data Drills and a set of raster data GeoDEM are formed.

This step specifically includes:

(1-1) Extracting regional geological boundary data and regional stratigraphic layer data from the regional geological map of the study area, and storing them in the regional geological boundary set GeoLine and the regional stratigraphic layer set GeoPolygon respectively;

(1-2) Extracting bedrock geological boundary data and bedrock stratigraphic layer data from the bedrock geological map of the study area, and storing them in a bedrock geological boundary set BedrockLine and a bedrock stratigraphic layer set BedrockPolygon respectively. The bedrock stratigraphic layer data includes the stratigraphic unique number GID of the bedrock stratigraphic layer and the corresponding stratigraphic code;

(1-3) Store the drilling data of the study area into the drilling data set Drills;

(1-4) Extract raster data from the DEM of the study area and store it in the raster data set GeoDEM.

(2) Obtain the intersection points of the profile line SL of the study area with each geological boundary in the set BedrockLine and the set GeoLine, respectively, to form the bedrock surface intersection point set PA and the regional stratigraphic surface intersection point set PB.

This step specifically includes:

(2-1) extracting the intersection point between the profile line SL and each bedrock geological boundary in the bedrock geological boundary set BedrockLine as the bedrock surface intersection point;

(2-2) The formation occurrence information of each bedrock surface intersection position is used as the attribute of the point and stored in the bedrock surface intersection set PA = {pa _i |i = 1, 2, ..., PI}, where pa _i represents the i-th bedrock surface intersection point and PI represents the number of bedrock surface intersection points; in this embodiment, PI = 26;

(2-3) extracting the intersection points of the profile line SL and each regional geological boundary in the regional geological boundary set GeoLine as the regional stratigraphic surface intersection points;

(2-4) The stratigraphic occurrence information of each regional stratigraphic plane intersection is used as the attribute of the intersection and stored in the regional stratigraphic plane intersection set PB = {pb _j | j = 1, 2, ..., PJ}, where pb _j represents the jth regional stratigraphic plane intersection and PJ represents the number of regional stratigraphic plane intersections. In this embodiment, PJ = 18.

(3) The bedrock surface intersection point set PA is used to segment the profile line SL to obtain the segment set SeLine. Then, combined with the bedrock stratigraphic surface set BedrockPolygon and the raster data set GeoDEM, the stratigraphic code set MK and the attitude set AT on the profile line SL are extracted, and the bedrock geological profile SP and the surface line SurfaceLine are generated.

This step specifically includes:

(3-1) The formation attitude information of all points in the bedrock surface intersection set PA is stored in the attitude set AT = {α _i (ρ, θ, δ)|i = 1, 2, ..., PI}, where α _i (ρ, θ, δ) represents the formation attitude of the i-th bedrock surface intersection point, ρ is the formation dip, θ is the formation dip angle, δ is the formation strike, and PI represents the number of bedrock surface intersection points;

(3-2) Use the points in the bedrock surface intersection point set PA to split the profile line SL into PI segment lines and store them in the profile segment line set SeLine;

(3-3) Get the first endpoint of each segment line in the profile segment line set SeLine, store the unique stratigraphic number GID of the bedrock stratigraphic layer where the first endpoint is located as the attribute of the corresponding segment line, and establish the association between BedrockPolygon and SeLine;

(3-4) For each segment line in SeLine, find the stratigraphic code of the corresponding bedrock stratigraphic layer in BedrockPolygon according to its attribute GID, and store it in the stratigraphic code set MK = {mk _i |i = 1, 2, ..., PI}, where mk _i represents the stratigraphic code of the i-th segment line;

(3-5) Based on the bedrock surface intersection set PA, the occurrence set AT and the raster data set GeoDEM, the bedrock cut geological profile SP and the surface line SurfaceLine are generated, as shown in Figure 4. The generation method can be found in the document: Application No.: 202010242546.3 "A method for automatically constructing a three-dimensional cut geological profile".

(4) The regional stratigraphic surface intersection point set PB is used to segment the profile line SL, and a segment set SbLine sorted from small to large is obtained. Then, combined with the regional stratigraphic surface set GeoPolygon, the loose layer profile line set FL and the loose layer stratigraphic code set QC are extracted.

This step specifically includes:

(4-1) According to the legend of the geological map of the study area, a loose layer covering strata code table PC with the stratigraphic age from new to old is established; the loose layer covering strata code table PC established in this embodiment is shown in Table 1.

Table 1 Code table of loose layer covering strata PC

(4-2) Use the points in the regional ground plane intersection point set PB to split the profile line SL into several segment lines and store them in the profile segment line set SbLine’;

(4-3) Obtain the first endpoints of all line segments in the section line segment set SbLine’, sort the line segments in ascending order according to the horizontal coordinates of the first endpoints, and obtain the section segment line set SbLine in an orderly arrangement;

(4-4) For each segment line in the profile segment line set SbLine, the unique stratigraphic number GID of the bedrock stratigraphic layer where its first and last endpoints are located is stored as its attribute, and an association is established between BedrockPolygon and SbLine;

(4-5) Get any segmented line in SbLine, and find the stratigraphic code of the corresponding regional stratigraphic layer in GeoPolygon according to its attribute GID;

(4-6) If the stratigraphic code of the segmentation line belongs to the loose layer cover stratigraphic code table PC, the stratigraphic code is stored in the loose layer stratigraphic code set QC, and the segmentation line is stored in the loose layer section line set FL;

(4-7) Loop through steps (4-5)-(4-6) until the set SbLine is traversed and the complete sets FL and QC are obtained.

(5) Based on the stratigraphic continuity relationship, the loose layer section line set FL is divided into different groups and stored in the loose layer section line grouping set FG.

This step specifically includes:

(5-1) According to the attribute GID of all segment lines in the segment line set SbLine, the GID of each loose layer profile line in the loose layer profile line set FL is obtained;

(5-2) Based on the GID of the loose layer profile lines in the set FL, determine whether any two loose layer profile lines are continuous according to the following rules: if the GID difference between the two lines is 1, the two lines are determined to be continuous; otherwise, the two lines are determined to be discontinuous;

(5-3) All continuous loose layer profile lines are divided into a group and stored in the loose layer profile line grouping set FG = {fg _v |v = 1,2,...,vn}, where fg _v represents the vth loose layer profile line group, vn represents the number of groups, fg _v = {sg _v,w |w = 1,2,...,wn}, sg _v,w represents the wth loose layer profile line in the vth group, and wn represents the number of loose layer profile lines in the vth group.

(6) Read any loose layer profile group fg _v from the set FG, obtain its adjacent drill holes from the drill hole set Drills, and obtain the loose layer thickness set DH of the group fg _v based on the loose layer stratigraphic code set QC.

This step specifically includes:

(6-1) Read any group of loose layer profile line groups fg _v in the loose layer profile line group set FG;

(6-2) Merge all the loose layer section lines in group fg _v to obtain a complete and continuous section line ft;

(6-3) According to the drill hole set Drills, obtain the neighboring drill hole drill that is closest to the section line ft;

(6-4) According to the loose layer stratum code set QC, the different loose layer strata in the group fg _v are obtained according to the relationship between the age of the strata;

(6-5) Read the thickness and lithology information of each layer in the adjacent drill hole, and according to the loose layer lithology classification in the regional geological map legend, integrate the thickness of each layer and store it in the loose layer thickness set DH = {dh(dc _o , _ho ) _o |o = 1,2,…,on}, where dc _o represents the oth loose layer layer, _ho represents the thickness of the oth loose layer layer, and on represents the number of loose layer layers. In this embodiment, the loose layer lithology classification is shown in Table 2 Loose Layer Lithology Table, and the number of layers of the two continuous section line groups is 2, and they are Q ₃ ^a1 and Q ₄ respectively.

Table 2 Loose layer lithology

(7) Based on the loose layer thickness set DH and the surface line SurfaceLine, the bottom lines of each loose layer are generated, and the loose layer profile is constructed and stored in the loose layer profile set QP.

This step specifically includes:

(7-1) Calculate the point drillPoint where the drillhole is projected onto the section line SL, convert it into a two-dimensional coordinate system, and obtain the horizontal and vertical coordinates (x _dp , y _dp ) of the point drillPoint; for the specific method, see the document: "A method for automatically constructing a three-dimensional geological section" Application No.: 202010242546.3;

(7-2) According to the loose layer thickness set DH, the lowest depth of each loose layer is obtained according to dh _o =y _{dp -ho} , and stored in the loose layer lowest depth set HP = {hp(dc _o , dh _o ) _o |o = 1, 2, ..., on}, where dc _o represents the oth loose layer, dh _o represents the lowest depth point of dc _o , and _ho represents the thickness of dc _o ;

(7-3) Read any stratum dc _o from the loose layer minimum depth set HP, extract the loose layer section lines with loose layer stratum code age less than or equal to dc _o from the group fg _v , and merge them into a section line fb;

(7-4) Get the two end points sp and ep of the profile line fb under the two-dimensional coordinates, and according to the lowest depth point dh _o of dc _o , get the bottom line of the loose layer stratum, and store it in the bottom line set QLine of the loose layer stratum;

(7-5) Loop through steps (7-3)-(7-4) until HP is completely traversed;

(7-6) Based on the surface line SurfaceLine and the loose layer bottom line set QLine, ArcEngineAPI is used to construct surface features, generate loose layer profiles, and store them in the loose layer profile set QP.

Wherein, step (7-4) specifically includes:

(7-4-1) Get the two end points sp and ep of the cross section line fb under the two-dimensional coordinates, and draw two perpendicular lines through the end points sp and ep;

(7-4-2) Read the lowest depth point dh _o of the formation dc _o , and draw a horizontal line that intersects the two vertical lines at points a _o and b _o ;

(7-4-3) Using the Bezier curve equation, generate two smooth curves between the three points sp, a _o , _dho and between the three points ep, b _o , _dho ;

(7-4-4) Merge the two curves as the bottom line of the loose layer stratum and store them in the loose layer stratum bottom line set QLine.

(8) Execute steps (6)-(7) repeatedly until the set FG is traversed and all loose layer profiles are constructed. , as shown in Figure 5.

(9) Based on all loose layer section geometries QP and bedrock cut geological sections SP, the cut geological sections of the loose layer covered area are constructed.

This step specifically includes:

(9-1) Assigning stratigraphic codes to the bedrock geological profile SP in sequence along the profile direction;

(9-2) Along the stratigraphic sequence, the stratigraphic codes are assigned to the loose layer section set QP in turn;

(9-3) Call ArcEngine API to merge the bedrock cut geological profile SP and the loose layer profile set QP to obtain the cut geological profile of the loose layer coverage area, as shown in Figure 6.

In the embodiment of the present invention, some GIS operations are provided based on ArcGIS Engine API, and the relevant steps can also use the API of software such as SuperMap and ArcGIS Object to perform corresponding GIS operations.

In the present invention, when bedrock geological map data is missing, bedrock stratum related information of the loose layer covered area can be obtained by the following method:

(1) Information on the occurrence of exposed bedrock strata and the surface intersection of strata and profile lines, obtained from regional geological maps;

(2) Inference of the location information of the bedrock strata in the area covered by the loose layer. If the exposed bedrock strata on the left and right ends of the loose layer are the same, it is inferred that the bedrock strata in the covered area are the same as the bedrock strata on the left and right ends; if the exposed bedrock strata on the left and right ends are different, the 1/2 point is taken as the dividing point between the two bedrock strata.

The automatically generated cut geological profile of the loose layer covered area (as shown in Figure 6) is compared with the manually hand-drawn cut geological profile (as shown in Figure 7). The results show that the similarity is high and the error is small. The experiment shows that the generation method has a high degree of automation and good recognition effect, which can meet the needs of automatic generation of cut geological profiles in loose layer covered areas.

The above disclosure is only a preferred embodiment of the present invention, and 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 (10)

1. An automatic generation method of a cut geological section facing to a loose layer coverage area is characterized by comprising the following steps:

(1) Forming a regional geological boundary set GeoLine, a regional stratigraphic surface set GeoPolygon, a bedrock geological boundary set BedrockLine, a bedrock stratigraphic surface set BedrockPolygon, a borehole data set Drills and a raster data set GeoDEM according to the regional geological map, the DEM, the borehole data and the bedrock geological map of the research region;

(2) Respectively acquiring intersection points of a section line SL of a research area and each geological boundary line in the aggregate BedrockLine and the aggregate GeoLine, and correspondingly forming a bedrock surface intersection point aggregate PA and an area ground surface intersection point aggregate PB;

(3) Dividing a section line SL by adopting a bedrock surface intersection point set PA to obtain a separated section set SeLine, and then combining the bedrock stratum surface set BedrockPolygon and the raster data set GeoDEM, extracting a stratum code set MK and a yield set AT on the section line SL, and generating a bedrock graph cut geological section SP and a ground surface line SurfaceLine;

(4) Dividing section lines SL by using a regional stratum intersection point set PB to obtain a branching section set SbLine which is ordered from small to large, and extracting a loose stratum section line set FL and a loose stratum code set QC by combining the regional stratum intersection point set GeoPolygon;

(5) Dividing the loose layer section line set FL into different groups based on stratum continuous relation, and storing the loose layer section line set FL into a loose layer section line grouping set FG;

(6) Reading any loose layer section line group FG _v from the set FG, acquiring adjacent drilling drill from the drilling set Drills, and obtaining a loose layer thickness set DH of the group FG _v based on a loose layer stratum code set QC;

(7) Generating a loose layer bottom line of each layer based on the loose layer thickness set DH and the surface line SurfaceLine, constructing a loose layer profile, and storing the loose layer profile into a loose layer profile set QP;

(8) Circularly executing the steps (6) - (7) until the set FG is traversed, and completing construction of all loose layer sections;

(9) And merging and constructing the cut geological section of the coverage area of the loose layer based on all the loose layer section geometries QP and the bedrock cut geological section SP.

2. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (1) specifically comprises:

(1-1) extracting regional geological boundary data and regional stratigraphic data from the regional geological map of the research region, and storing the regional geological boundary data and the regional stratigraphic data into a regional geological boundary set GeoLine and a regional stratigraphic set GeoPolygon respectively;

(1-2) extracting bedrock geological boundary data and bedrock stratum surface data from a bedrock geological map of the research area, and respectively storing the bedrock geological boundary set BedrockLine and the bedrock stratum surface set BedrockPolygon, wherein the bedrock stratum surface data comprises a stratum unique number GID and a corresponding stratum code of the bedrock stratum surface;

(1-3) storing borehole data for the investigation region into a borehole data set Drills;

(1-4) extracting raster data from the DEM of the investigation region, and storing the raster data into a raster data set GeoDEM.

3. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (2) specifically comprises:

(2-1) extracting intersection points of the section line SL and each bedrock geological boundary in the bedrock geological boundary set BedrockLine as bedrock surface intersection points;

(2-2) storing formation occurrence information of each bedrock face intersection position as an attribute of the point into a bedrock face intersection set pa= { PA _i |i=1, 2, …, PI }, wherein PA _i represents an ith bedrock face intersection point, and PI represents the number of bedrock face intersection points;

(2-3) extracting intersection points of the section line SL and each regional geological boundary in the regional geological boundary set GeoLine as regional ground plane intersection points;

(2-4) storing the formation occurrence information of each regional formation intersection position as an attribute of the intersection, and storing a regional formation intersection set pb= { PB _j |j=1, 2, …, PJ }, wherein PB _j represents the jth regional formation intersection, and PJ represents the number of regional formation intersections.

4. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (3) specifically comprises:

(3-1) storing formation occurrence information of all points in the bedrock surface intersection point set PA into an occurrence set at= { α _i(ρ,θ,δ)|i＝1,2,…,PI},α_i (ρ, θ, δ) representing formation occurrence of the ith bedrock surface intersection point, ρ being formation tendency, θ being formation inclination angle, δ being formation trend, and PI representing the number of bedrock surface intersection points;

(3-2) dividing the section line SL into PI section lines by using points in the bedrock surface intersection set PA, and storing the PI section lines into the section line set SeLine;

(3-3) acquiring a head point of each section line in the section line set SeLine, storing a stratum unique number GID of the bedrock stratum where the head point is located as an attribute of the corresponding section line, and establishing the association between BedrockPolygon and SeLine;

(3-4) for each segment line in SeLine, finding the stratum code of the bedrock stratum level corresponding to the stratum code in BedrockPolygon according to the attribute GID, and storing the stratum code into a stratum code set mk= { MK _i |i=1, 2, …, PI }, wherein MK _i represents the stratum code of the ith segment line;

(3-5) generating a bedrock diagrammatical profile SP and a surface line SurfaceLine from the bedrock surface intersection set PA, the occurrence set AT, and the raster data set GeoDEM.

5. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (4) specifically comprises:

(4-1) establishing a stratum code table PC of loose stratum coverage stratum from new stratum to old stratum according to a geological map legend of a research area;

(4-2) dividing the section line SL into a plurality of section lines by points in the regional ground plane intersection point set PB, and storing the section lines in the section line set SbLine';

(4-3) acquiring the head points of all the parting lines in the parting line segment set SbLine', and sequencing the parting lines from small to large according to the abscissa of the head points to obtain a orderly arranged parting line segment set SbLine;

(4-4) for each segment line in the set SbLine of section segment lines, storing a stratum unique number GID of the bedrock stratum level where the head end point is located as an attribute thereof, and establishing an association between BedrockPolygon and SbLine;

(4-5) obtaining SbLine any segment line, and finding out stratum codes of the regional stratum surface corresponding to the segment line in GeoPolygon according to the attribute GID;

(4-6) if the stratum code of the segment line belongs to the loose layer coverage stratum code table PC, storing the stratum code into a loose layer stratum code set QC, and simultaneously storing the segment line into a loose layer section line set FL;

(4-7) steps (4-5) - (4-6) are performed in a loop until set SbLine is traversed, resulting in complete sets FL and QC.

6. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (5) specifically comprises:

(5-1) obtaining the GID of each loose layer section line in the loose layer section line set FL according to the attribute GID of all the section lines in the section line set SbLine;

(5-2) determining whether any two loose layer section lines are continuous according to the GID of the loose layer section lines in the set FL and the following rule: if the GID difference between the two lines is 1, judging that the two lines are continuous; otherwise, judging that the two lines are discontinuous;

(5-3) grouping all consecutive loose layer section lines into a group, storing the loose layer section line grouping set fg= { FG _v |v=1, 2,.. where FG _v represents the v-th loose layer section line grouping, vn represents the number of groupings, FG _v＝{sg_v,w|w＝1,2,...,wn},sg_v,w represents the w-th loose layer section line in the v-th group, and wn represents the number of loose layer section lines in the v-th group.

7. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (6) specifically comprises:

(6-1) reading any one of the loose layer section line groupings FG _v within the loose layer section line grouping set FG;

(6-2) merging all loose layer section lines in the group fg _v to obtain a complete continuous section line ft;

(6-3) obtaining adjacent drill holes drill closest to the section line ft according to the drill hole set Drills;

(6-4) acquiring different loose stratum in the group fg _v according to the loose stratum code set QC and the new-old relation of stratum ages;

(6-5) reading the thickness and lithology information of each layer of the stratum in the adjacent borehole drill, and classifying the lithology of the unconsolidated layers according to the legend of the geological map of the region, integrating and storing the layer thicknesses into a unconsolidated layer thickness set dh= { DH (dc _o,h_o)_o |o=1, 2, …, on }, wherein dc _o represents the o-th unconsolidated layer stratum, h _o represents the thickness of the o-th unconsolidated layer stratum, and on represents the number of unconsolidated layer strata.

8. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (7) specifically comprises:

(7-1) calculating a point drillPoint of the drill hole drill projected to the section line SL, and converting the point drillPoint into a two-dimensional coordinate system to obtain an abscissa (x _dp,y_dp) of the point drillPoint;

(7-2) obtaining the lowest depth of each stratum of the loose layer according to DH _o＝y_dp-h_o from a loose layer thickness set DH, and storing into a loose layer lowest depth set hp= { HP (dc _o,dh_o)_o |o=1, 2, …, on }, wherein dc _o represents the o-th loose layer stratum, DH _o represents the lowest depth point of dc _o, and h _o represents the thickness of dc _o;

(7-3) reading any stratum dc _o from the lowest depth set HP of the loose layers, extracting the section line of the loose layers with the stratum code time less than or equal to dc _o from the group fg _v, and merging the section lines into a section line fb;

(7-4) acquiring the end points sp and ep of the section line fb under the two-dimensional coordinates, obtaining a unconsolidated formation bottom line according to the lowest depth point dh _o of dc _o, and storing the unconsolidated formation bottom line set QLine;

(7-5) cyclically performing steps (7-3) - (7-4) until HP is traversed;

(7-6) constructing planar elements from the surface lines SurfaceLine and the loose layer formation bottom line set QLine, generating a loose layer profile, and storing the loose layer profile set QP.

9. The automated generation method of a cut geological profile for a loose layer coverage area of claim 8, wherein: the step (7-4) specifically comprises:

(7-4-1) obtaining the end points sp and ep of the head and tail of the section line fb under the two-dimensional coordinates, and drawing two perpendicular lines passing through the end points sp and ep;

(7-4-2) reading the lowest depth point dh _o of the stratum dc _o, and making horizontal lines to respectively cross two perpendicular lines at a point a _o、b_o;

(7-4-3) generating two smooth curves between sp, a _o、dh_o three points and ep, b _o、dh_o three points using a bezier curve equation;

(7-4-4) combining the two curves as unconsolidated formation bottom lines and storing the unconsolidated formation bottom line aggregate QLine.

10. The method for automatically generating a cut geological profile for a coverage area of a loose layer according to claim 1, wherein the method comprises the following steps: the step (9) specifically comprises:

(9-1) sequentially giving stratum codes to the bedrock graphic geological section SP in the section direction;

(9-2) sequentially assigning a stratigraphic code to the set of loose layer profiles QP along the stratigraphic sequence;

(9-3) combining the bedrock cut geological section SP and the loose layer section set QP to obtain the cut geological section of the loose layer coverage area.