interpreting seam data

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Interpreting Seam Data Tutorial For Minex v5.3 April 2008

Table of Contents Introduction .............................................................................................................................. 3

Requirements ........................................................................................................................... 3

Objectives ................................................................................................................................. 4

Storing Seam Data in the Borehole Database ...................................................................... 5

Graphical Seam Input ............................................................................................................ 12

Validating Seam Intervals ..................................................................................................... 18

Seam Data Report .................................................................................................................. 19

Plotting seam correlation lines on borehole cross sections ............................................ 21

Collecting and Storing Seam Mapping Data ....................................................................... 22

Using 3D Sirovision Images to Input Seam Data ............................................................... 22

Importing and Displaying a 3D Sirovision Image ............................................................... 22

Digitising Seam Boundaries on a 3D Sirovision Image ..................................................... 24

Summary ................................................................................................................................ 25

Introduction

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Introduction Seam data can be in the form of borehole seam intervals and mapping data stored as strings and points in the geometry file. Borehole seam intervals are stored in the .B33 database file separate from the downhole sampling and geological logging data. They may be interpreted from borehole sampling information and added to the database at any time. These borehole seam intercepts may be used for reporting, plotting and correlating to form a bore seam model. Seams or layers that are interpreted are then entered into a seam sequence list (stored in the .B35 file) which defines them in stratigraphic order. These are also assigned flags which define them as COAL or WASTE material, a default density, a pen number used for graphics display and a related seam if a relationship exists.

Requirements For this tutorial you will need:

• To have a basic understanding of the Minex borehole database with the ability to create a new borehole database.

• To understand the concept of gridded seam modelling used to model coal seams in Minex.

The following files are required for this tutorial:

• ASHES.B31, ASHES.B32 and ASHES.B34 borehole database files – the borehole database created in the Tutorial “Loading Sampling Data into the Borehole Database”.

• ASHES_INPUT_PICKS.csv

• LITHOLOG.SYM – borehole geological symbols file

• LITHOLOG.DIC – borehole geological dictionary file

• SYMBOLS.PAR – colour and line patterns symbol file

• ASHES_HIGHWALL40_3D_Image.tif – 3D Sirovision image of highwall geology

• ASHES.mpf – parameter file

• THEDON.GM3 – geometry file

Objectives


To set the following local origin for this dataset, 1. Choose Tools > Options > Local Origin.

2. Click Ok.

Objectives From this tutorial you will learn to:

• Create a seam/layer sequence (*.B35) file • Interpret seam intervals interactively from a section showing sample data • Load and validate a seam interval data file • Run a stratigraphic check and correct any errors • Plot borehole data and seam intervals with seam correlation lines on cross section • Import a 3D Sirovision image of a highwall • Digitise seam boundary data using the 3D Sirovision image and store the data in the

geometry file to be used later in seam gridding.

Storing Seam Data in the Borehole Database


Storing Seam Data in the Borehole Database Seam models in Minex are created from seam intervals interpreted from borehole sampling data such as logged geology and downhole geophysics and from digitised seam data stored in the geometry file. Interpreted borehole seam intervals are stored separately from sample data in a borehole database file with .B33 suffix. These seam intervals maybe interactively interpreted from borehole profile or section displays or loaded from seam interval (known as “pick”) files. However before you can add seam picks to the borehole database, you need determine and store the correct stratigraphic sequence of the seams by creating a Seam/Layer Sequence List. This list will be stored as the .B35 file.

Interpreting Seam Stratigraphy The following is an extract from the pick file ASHES_INPUT_PICKS.csv supplied with this tutorial. Pick files contain FROM and TO depth intervals, a CLASS number and a SEAM name. By looking at the seam intervals in this pick file you should be able to work out the stratigraphic order of the seams in the ASHES coal deposit.

BOREID FROM TO SEAM CLASS SEAM NAME

BNBG1 74.28 75.966 1 SW1 BNBG1 75.966 77.652 1 SW2 BNBG1 210.684 211.714 1 ABU BNBG1 211.714 213.468 1 ABL BNBG1 283.764 286.704 1 ST BNBG1 289.332 291.324 1 DL BNBG1 304.116 306.06 1 UGB BNBG1 323.292 323.964 1 MGB1 BNBG1 324.888 325.836 1 MGB2 BNBG1 338.496 340.956 1 ULGB BNBG1 341.448 342.36 1 LLGB BNBG1 359.496 361.488 1 UDB BNBG1 375.852 378.264 1 LDB BNBG2 22.164 25.068 1 LDB BNBG2 43.92 45.6 1 WGG1 BNBG2 56.7 57.756 1 WGG2

The SEAM CLASS number is set to 1 when preliminary seam intervals are Input. The seam class number will be discussed later.

Creating a Seam/Layer Sequence List To create your own seam sequence scroll through the ASHES_INPUT_PICKS.csv file and write down all the seams available in the file (e.g. SW1, SW2, ABU etc) and write them in the order they occur in within each borehole: Top seam SW1 Seam 2 _______ etc Bottom seam WGG2 You have now defined a stratigraphic list of seams.



To create a Seam/Layer Sequence List in Minex as a framework for the .B35 file:

1. Choose BoreholeDB > File > Edit > Create/Edit Seam Sequence. In the Seam code column enter the seam sequence you obtained from the .A33 text file.

2. Press F7 to copy lines.

3. Leave the Father code field blank and tick the Father From Seam check box. When you save the list, the software will assign the Seam code to the Father code. The Material code field gives the type of material within that seam e.g. COAL, WASTE, ORE etc. All the seams you will be entering are coal seams.

4. In the Density field column add the default density of coal to 1.4.

5. Choose colours based on the seam groupings so you can visually differentiate between seams of different seam groupings.

6. Set the Priority field for all seams to 1. Priority is set for the interpolation phase of the seam modelling. It allows you to set seams with more information to have a greater priority when interpolating seams than those with little data.

7. Leave the Expansion field blank. This field is used as a tool for describing seams or inputting actual seam names.

8. Select the Create Pick File check box. This will create a .B33 file using the seam sequence you have specified.

9. Click Save. You may be prompted by the software if you want to delete the seam picks for the seam(s) you are deleting,

10. Select NO. Go to the Minex Explorer and click on the cross and drill down to the Seam Interval and Stratigraphic Sequence menu. Under the Stratigraphic sequence you will see all the seams you have just entered in the appropriate stratigraphic sequence as shown below.



You have just set up the .B35 file which stores all the data relating to stratigraphic order, default density, colour, priorities and material, of seams. To save the borehole database,

11. Choose File > Save > Save Borehole DB.

Now check your seam sequence against the following and make any edits required:

SW1 SW1 COAL 1.40 1 1WARNE SEAM1

SW2 SW2 COAL 1.40 1 1WARNE SEAM2

ABU ABU COAL 1.40 1 1UPPER BORDER SEAM

ABL ABL COAL 1.40 1 1LOWER BORDER SEAM

ST ST COAL 1.40 1 1TENDULKAR SEAM

UDL DL COAL 1.40 1 1UPPER LILLIE SEAM

DL DL COAL 1.40 1 1LOWER LILLIE SEAM

UGB UGB COAL 1.40 1 1UPPER BOYCOTT SEAM

MGB1 MGB1 COAL 1.40 1 1MIDDLE BOYCOTT 1SEAM

MGB2 MGB2 COAL 1.40 1 1LOWER BOYCOTT SEAM

ULGB ULGB COAL 1.40 1 1UPPER LOWER BOYCOTT SEAM

LLGB LLGB COAL 1.40 1 1LOWER LOWER BOYCOTT SEAM

LLGB1 LLGB COAL 1.40 1 1LOWER LOWER BOYCOTT SEAM

LLGB2 LLGB COAL 1.40 1 1LOWER LOWER BOYCOTT SEAM

UDB UDB COAL 1.40 1 1UPPER BRADMAN SEAM

UDBS UDB COAL 1.40 1 1UPPER BRADMAN SPLIT

LDBS LDB COAL 1.40 1 1LOWER BRADMAN SPLIT

LDB LDB COAL 1.40 1 1LOWER BRADMAN SEAM

WGG1 WGG COAL 1.40 1 1UPPER GRACE SEAM

WGG2 WGG COAL 1.40 1 1LOWER GRACE SEAM



Loading Seam Interval Data Now that you have set up the .b35 seam sequence file you can load the seam interval data into Minex. However you first need to set the Seam Interval File to Read/Write.

1. Highlight Interval under the Borehole Database in the Minex Explorer window.

2. In the Properties window change the Read Only field from True to False.

Now the Seam Interval file is editable you can load your Seam Interval data into the database.

3. Choose BoreholeDB > Load > Load Seam/Layer ASCII.

4. Select ASHES_INPUT_PICKS.csv from your working directory.



5. Click the Create/Edit button to create a Format File, then display the Variable setup tab to see that the .csv file has the correct headers: BOREID, FROM, TO, SEAM CLASS and SEAM NAME:

6. Click Ok to save the format file and return to the load menu.

This command creates a file called ASHES_INPUT_PICKS.sff and stores it in your nominated working directory.



You may be prompted to Over write Existing file.

7. Select Overwrite Existing Data or choose Yes. This will avoid duplicating data that may already exist in the database. Leave the remaining window settings as they are.

8. Click Ok to Import Seam/Layer Interval (Pick) Files. The seam load report (see below) will be sent to the Output window:

9. Click Cancel to close the dialogue.

Graphical Seam Input


Graphical Seam Input Borehole seam intervals can be interactively added and edited via screen digitising using single hole, profile, section or 3D borehole display of sample data such as geological logging, geophysical and coal quality data. As example the seam load report shown above shows line 668 in the pick file ASHES_INPUT_PICKS.csv shows that hole BNBY50C has an undefined seam name ULGBX from 27.27 to 30.44 m. Hole BNBY50C was one of the holes you displayed with geology and downhole geophysics in the tutorial “Loading Sample Data Into the Borehole Database”. So you can use that display of data now to try the graphical seam input function. Plot holes BNBY50C and BNBG23 (an adjacent hole) using the Profile Plot function via the menu path:

1. Choose BoreholeDB > Plot > Profile

2. Choose the tabs as shown below and enter the values into the dialogue boxes as shown in the images below:



3. Click Ok to produce a graphical image as shown below.



Now access the Seam Input menu

4. Choose BoreholeDB > Edit > Add/Edit Seam Intervals. Ensure the borehole BNBY is selected.

5. Click Pick button to digitise any where in the trace of BNBY50C to select the hole.

From the comparison with hole BNBG23 you can see that the missing seam is ULGB, so

6. Enter <ULGB> in the Seam Name field.



7. Click Input Seam Extents button and digitise in the trace of hole BNBY50C the roof and floor points such that the mid point on the sloping sides of the red histogram of the DENLS values are intersected by the cross hairs. The depths should be approximately 27m to 30m depth down the hole.

8. Click Ok. The graphical image will be redrawn with the new pick for ULGB shown and the Update Table in the Seam Input menu will show the composite values for other variables for the new pick in hole BNBY50C.

9. Now save the borehole database so that the pick is saved in the .B33 database file.

Validating Seam Intervals


Validating Seam Intervals The process of seam validation checks each individual borehole and produces a report which lists the:

• Borehole Processed - those boreholes selected and processed, • Barren Boreholes - those holes which have no seam pick intervals, • Negative Thickness - those holes which, due to error in data entry, have a seam floor

above the seam roof, • Undefined From/To - where a seam name (ID) has been input, but where the seam roof

and/or floor depth has not been defined, • Missing Seams in Whole Borehole - lists the seams from the Stratigraphic Sequence

which have not been defined in the seam pick for a borehole, • Missing Seams inside known Borehole - lists the seams which have not been defined

between known picks for a borehole., and • Missing Seams outside known Intervals - lists the seams which have not been defined

above the uppermost known seam pick as well as below the lowermost known seam pick for a borehole.

The report obtained from this process will change as further Bore Seam Modelling processes are performed. Therefore, it is recommended that validation should be checked on a regular basis.

Run the Seam Validation report and correct any errors To access the seam validation report menu

1. Choose BoreholeDB > Reporting > Report Seam Validation.

2. Click Ok to produce the Seam Validation report in the Output window. ======================== Borehole Seam Validation ======================== Barren boreholes ---------------- Borehole BBNB0 has no seams defined Borehole BBNB1 has no seams defined Borehole BCNB1 has no seams defined Borehole BNBY92 has no seams defined Borehole BNBYC100 has no seams defined Borehole BNBYC98 has no seams defined Borehole BNBYC99 has no seams defined Negative thickness ------------------ Negative interburden thickness ------------------------------ Undefined FROM or TO Variables: ------------------------------

Seam Data Report


Seam Data Report The Seam Data Report can be used to summarise on a seam basis how many picks have been input both by pick file loading and by interactive seam input. To access this reporting function:

1. Choose BoreholeDB > Reporting > Report Seam Data

2. Select the Summary Only and Seam Name options and the seam thickness variable SEAMTH.

3. Click Ok and see the report in the output window. As the example below shows, you can use this report to compile a summary of the “input” picks for each seam using CTRL+C and CRTL+V into a MS Excel spreadsheet.

========================= Borehole Seam Data Report ========================= -------------------------------- Borehole Seam Name Thick -------------------------------- ---- Seam :UGB : Report ---- -------------------------------- BNBY23 3.12 -------------------------------- Mean_Value : 3.12 Max_Value : 3.12 Min_Value : 3.12 No. Samples : 1 -------------------------------- ---- Seam :MGB1 : Report ---- -------------------------------- BNBY23 1.08 BNBY50C 0.23 -------------------------------- Mean_Value : 0.66 Max_Value : 1.08 Min_Value : 0.23 No. Samples : 2 --------------------------------

Seam Data Report


SEAM Av.

SEAMTH No.

Samples SW1 3.16 9 SW2 3.22 9 ABU 0.94 24 ABL 1.77 31 ST 2.68 57 UDL 0.68 9 DL 2.04 55 UGB 2.65 61 MGB1 0.96 76 MGB2 1.11 77 ULGB 2.52 83 LLGB 1.14 68 LLGB1 0.54 17 LLGB2 0.5 17 UDB 1.72 100 UDBS 1.25 53 LDBS 1.06 42 LDB 2.89 98 WGG1 1.13 27 WGG2 0.85 25 Total 938 From this seam summary you can see some important aspects of the seam correlation for the deposit such as the abundant picks for seams ULGB (83), UDB (100) and LDB (98), whilst UDL has only 9 picks.

Plotting seam correlation lines on borehole cross sections


Plotting seam correlation lines on borehole cross sections Refer to the section Preparing a Borehole Section Plot in the Tutorial “Loading Sample Data into the Borehole Database”. Turn on the Plot Seam/layer IDs and Plot Correlation Lines in the ID’s tab of the Borehole Section Plotting menu. To plot correlation lines connecting seam intervals on a borehole section plot tick the Plot Correlation Lines option in the ID’s tab of the Borehole Section Plotting menu.

Collecting and Storing Seam Mapping Data


Collecting and Storing Seam Mapping Data Most seam mapping data is collected as surveyed seam roof and floor strings from exposed geology on highwalls or on the wall and roof of underground openings. In most open cut mines the seam roof boundary is typically cleaner and better exposed than seam floor boundaries. These strings are typically collected by the mine surveyor and stored in the geometry file in a map name such as SEAM. Each string and point is assigned an identifier which conforms to the naming conventions for seam grids – UDBSF for example would be used for structure floor data for seam UDB.

Using 3D Sirovision Images to Input Seam Data Sirovision, an innovative software program developed by the CSIRO in Australia, uses digital cameras and terrestrial photogrammetry to produce accurately surveyed 3D images of highwalls which can be directly input and used in Minex. Once displayed in the 3D design window, you can digitise seam boundaries on the 3D surface using the photographic image detail.

Importing and Displaying a 3D Sirovision Image To import the Sirovision image file ASHES_HIGHWALL40_3D_Image.tif

1. Right-click on the file name in the Minex Explorer window,

2. Choose Save Tif as Triangle.

Then in the Save Tif as Triangle menu name the .TR5 and .TRN registration files to be saved.

3. Click Ok.

Importing and Displaying a 3D Sirovision Image


To view the image in the 3D Design window you may have to delete other objects and reset the 3D area. Then drag and drop the .trn file ASHES_HIGHWALL40_3D_Image.trn into the 3D design window and reset the 3D area to view the highwall image. To locate the position of the image you can plot boreholes.

Hint: To be able to rotate the highwall image easily, digitise the centre of rotation by clicking on the image using the “snap to solid” option.

Digitising Seam Boundaries on a 3D Sirovision Image


Digitising Seam Boundaries on a 3D Sirovision Image Whether you are digitising seam boundaries on Sirovision images or importing boundary strings picked up by a mine surveyor, it is important that you store the strings in the geometry file in such a way as to use them easily for gridding. It is recommended that you store all seam mapping data in the one map eg. SEAMS and that you name each string according to the seam name it will be used to create ie. Seam name plus SR for roof, SF for floor and ST for thickness. To digitise the seam roof boundary on the Sirovision 3D image make sure you will store the resulting string in the map name SEAMS and the appropriate ident name (seam name plus SR for seam roof or SF for seam floor) eg. UDBSF

Each imported Sirovision creates a triangle surface and it is this triangle surface that you will use to digitise seam boundaries. Make sure then that you are in “Snap to point” mode before you start digitising and that you have selected the appropriate map (SEAMS) and ident name (UTBSF).

Summary


Summary You should now be familiar with the way seam intervals are loaded and stored in the borehole database. You are now ready to progress to the next tutorial “Modelling Topography and Weathering”. You have learned how to:

• Create a seam/layer sequence (.B35) file • Format the seam interval (.A33) data file • Load and validate the seam interval data • Input seam interval data interactively by screen digitising on a profile plot • Run a stratigraphic check and correct any errors • Report a seam thickness summary showing average thickness and number of picks for each

seam. • Plot borehole data and seam intervals with seam correlation lines on cross section. • Digitise seam boundary data using a 3D Sirovision image of a highwall and store the data in

the geometry file to be used later in seam gridding.

interpreting seam data

Documents

3d design window

choose boreholedb

3d sirovision image

storing seam data

3d sirovision images

digitising seam boundaries

seam correlation lines

borehole cross sections