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Converting one 2D geological section plot into 3D one

Robert 8 years ago in Vizex updated 8 years ago 1
Purpose:
Converting one 2D geological section plot into 3D one.


Background:
Most of Chinese geological exploration company draw a series of 2D geological section plot with AutoCAD or Mapgis , with these geological section plot ,geologist can interpret orebody and calculate volume and tonnage of ore block between two adjacent sections. Obvious this approach is very traditional and time-comsuming.
After some of geological exploration company bought 3D exploration software such as Micromine , they want toload and display their previous 2D section plot into 3D visualization environment . After loading into Vizex , the interpreting and wireframing and calculation process will become easier and quicker and intuitive than before.

Approach in MM:
Original data : 2D geological section plot which format is DXF ,which plot using AutoCAD ;

Steps:
1. In AutoCAD ,open 2D section plot :We need to check the coordinates of this plot , if there are recorded with plotting dimension which unit is millimeter , we need to translate and scale their coordinates to world coordinates in AutoCAD.
Then save this plot as DXF format which can be imported into MM later;

2. In MM ,import above DXF file as new MM string file, as below screen shot picture showed :
Image 534

After succeed to import DXF into MM file ,then open this mm file , you will find there are two columns which record 2D coordinates.
Actually ,in MM it will need three columns to record 3D coordinates. So we need to add a new field(column of North) in this file;

Meanwhile ,the previous “North” field in 2D plot is “RL” field in 3D plot , we need to rename the field of “North” as ”RL”.
As below picture showed:

Image 535

3. Calculate new values for field of “North” , in MM run functionality of Survey |Convert Coordinates Between | Plane Grids,In the form of this function , you need to specify angle of section plot in the plan view and add two new fields to store new calculated East/North coordinates value which will be used when display in Vizex;
If there are many 2D section plot which need to be converted ,we can use macro.
As below screen shot picture showed:
Image 536

4. After finished all of converting from 2D to 3D ,then we can display the real 3D geological section plot which used their converted coordinates in step3,As below picture showed:
Image 538
Image 537
5. Geologist continue to do future works: interpreting , wireframing ,resource estimation ,etc.

Continue ....

For vector format of geological section plots , we can deal with them as above doc said,
For raster formst of geological section plots, we can deal with them as below steps:


Background :
Sometimes  resource estimation company get geological section plots which stored as raster format ,such as bmp. tiff, png,etc. from his clients. Those images contain important geological information ,such as boundary of orebody , fault, drillhole trace, etc. How to ustilize those informaiton for future resource estimaiton work?

Steps:

1. load a image file into vizex by Vizex | image, as below showed




2. georeference above picture with four refereced points which geological section map showed,
In particular ,in china ,most of geological section map will disply 3D coordinates of two beginning and ending points of section line ,the point 1 and 2 on above picture ,which coordinates are knowned.
 We can also get other two  points of 3 and 4 on above picure ,which coordinates need to be calculated manually.

For a geological section plot , its dip is -90 and it is vertical .So the X and Y coodinates of Point 3 are same as X and Y of point 1 ,  Z coordinates of point 3 is equal to z coordinates of point1 - depth between point 1 and point 3 ,which we get from this plot. 

As the same approach ,we can also get coordinates of point4 from point 2.




3. georeferece four points , as below picture showed:




4. Display the georeferenced picture in Vizex with DTM , DrillHole trace ,ect.As below picture showed:




5. geologist continue to cut section , interpret based on informaiton on image , wireframing , modelling ,resource estimation ,etc. Below picture show a section with the picture :