Geophysical data in Micromine

kentbalas 7 years ago in Geology updated by Paul Hooykaas 7 years ago 25


, I have a CSV with X,Y,Z,conductivity,resistivity values. Is there a simple workflow to display these data in Micromine? I have imported the CSV with the text import tool and created a *.DAT, but struggling with where to go from here? Is the best way to use the block model tool? Any help people could offer would be appreciated.

Hi! Is this downhole data or it is planar survey?

Ok! you can use grids for data representation.

So I would import the CSV using the text import, the Grid -> create? The problem I'm having is I need to display multiple point levels - for example each X,Y point has ~10Z points representing the conductivity changing with depth. When I use the grid function in Micromine it only displays a single Z value - ie a single depth of conductivity. Below is a sample of the data format:

Line Location RL East North Resistivity_ohmm Log_Resistivity Conductivity_mS_m Log_Conductivity
100101 25 556.4 x y 654.29 2.82 1.53 0.18

so it is downhole data. do you have collars for this survey?

what do you want to see in the result? the downhole graphs? or the average value for the collar?

No it is not downhole - it is airborne electromagnetic data. I guess it could be thought of as downhole data. I want to load all of the X,Y,Z points and then use a interpolation method do create a 3D representation of conductivity values.

so you can use Point layer to display the survey in the Vizex forms, you will have the points cloud.

You can use color coding to display the values.

Sorry I didn`t know that we could have the airborn survey in such representation.

ah great, that worked. Can i then interpolate between the values of those points using Kringing? How would I do that?

If you want to interpolate these values you can use blank block model created in the specified limits. For interpolation you can use the Inverse distance weights method.

double click on the points layer, input your survey as file, enter coordinate fields.

Was the data was originally in UBC format?

No, it's an Intrepid Inversion

I was looking at the GeoModeller documentation http://www.intrepid-geophysics.com/ig/uploads/manuals/documentation_pdf_geomodeller/pdf_en/GeoModeller_Reference.pdf
and I see that they can Export to UBC format.

Micromine can import UBC (File | Import | Block Model) directly, so this might be something to look at if you have more of this type of data in the future.

Once you have the data in Block Model format (in Micromine) there are three useful things you can do. All assume that you have defined a sensible colour set for the conductivity and resistivity values:

The first is to use the Interactive Block Visibility option when displaying the BM. This is on the Display Options tab and the interactive slider is a really neat way to look at this sort of data and can very quickly determine the location and shape of interesting regions.

The second is to use the Wireframe | Block Model Grade Shells to create iso-surfaces of one (or more) of the conductivity or resistivity values.

Thirdly you can display the data as Points and turn on "Use Maximum Intensity Projection". This also lets you visualise the regions with high values.

yes you can, firstly you have to create blank block model through modelling - block model tools - create blank

Please, type the name of the output file and the name of the coordinate fields

enter the limits for the blank block model and the sizes for the blocks in block definitions tab

after the blank block model is created, you can interpolate all the data to it.

if you want to use Kriging method you have to do geostatistical analysis, You have to posses enough data for it, cause kriging doesn`t work with small number of points.

To do this analysis you have to use stats - semivariograms.

Which function do I use to interpolate the data to the blank block model?

After you made the analysis, you have to interpolate the values through the Modelling - 3d block estimate - Kriging

if you need any help in the analysis and interpolation, please let us know! we are ready to help!

You can also use IDW which doesn`t need the geostatistical analysis to be made,


Given that it's an inversion you don't need to re-interpolate the values.You've already indicated that the the X-Y and Z coordinates are spaced at regular intervals throughout the file, so you're good to convert the data directly to a block model.

After importing the file via File | Import | Text (which you've already done), you can convert it directly to a block model via two extra steps:

  1. Add dimension fields to your imported file, which tell Micromine how large each cell (block) in the model is. There is a simple rule for naming them: whatever your X, Y, and Z coordinate fields are called, you use the same name prefixed with a "_" to create the matching dimension field. So, if your X coordinate field is called EAST_UTM, then the dimension field will be called _EAST_UTM. You can give the dimension fields the same type, width and decimals as the original coordinate fields.

  2. Process the imported block model file via Modelling | Block Model Tools | Convert Imported Data to Block Model. This will take care of all of the numerical data and ensure the file is consistent.

From there you can display the model as a Block Model Vizex form.

I've created the dimension fields - do I leave the values here blank or should I enter the block size?

If you know the block sizes you may as well enter them.

So for example, I've created a file that looks like this with 50*100*100 blocks:

Is it correct if I then setup the create block model from imported data like this?: