WinDisp Drillhole Posting Menu

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WinDisp Drillhole Posting Menu

Drillhole Posting

This option produces a drillhole trace for each specified data value. The data values are plotted as bars starting at the drillhole trace. The height of the bar is proportional to the data variable assigned to that bar.

After selecting that the posting style is Drillhole, you need to define the coordinates to be used for plotting the drillholes. With Drillhole posting it is assumed that the data file includes x,y and z coordinates and that the aim is to plot a section through the drillholes. To do this you first need to specify the x and y coordinates for the drillhole traces. This is done on the Data Posting Coordinates form as follows:

The X and Y coordinates are the lateral coordinates in the drillhole data file. Generally the X coordinate will be the Easting coordinate and the Y coordinate will be the Northing.

Also on this form, you can specify which field in the drillhole data file contains the Drillhole name field. You do this by clicking on the text box next to the Line Variable label and selecting the required name field from the drop-down list that is displayed. If the name field contains values which are not numeric (or non-integer), then turn on the Line Variable is Text check box so that the names will be recognised and displayed correctly.

When Drillhole posting is selected the Data Posting Specification menu has the following form:

This menu display contains a number of standard items which are displayed for all menu styles and a number of items which are specific to the particular posting style.

General Posting Options

Drillhole Specific Specifications

With Drillhole posting up to 128 data values can be selected. These data values are chosen from the available data items by clicking in the grid cell under the column heading Name of Data Variable in the preferred row in the data definition grid. These rows must be defined contiguously. Clicking in any cell in the Name of Data variable column brings up a drop down box from which the desired data variable can be chosen.

Sampling Interval

With Drillhole plotting, all data is read from the drill xyz data file and saved in a temporary binary file. When the data is displayed, all samples within the specified sampling interval are averaged and a single bar is displayed using the average of these values.

Depth Variable

This field is used to select the depth data column from the drillhole data file. This value has to be supplied and it has to contain values that are positive up (ie RL values rather depth below surface).

Line Label Size

This field specifies the size in cm of the labels to be plotted at the start and end of the drillhole trace.

Start East, Start North

These fields specify the X and Y coordinates of a point on the section line to be displayed. The point does not have to be located at the start of the section, but the centre line of the section to be displayed passes through this point.

Section Azimuth

This field specifies the direction of the section through the specified Start East, Start North location. The azimuth is in decimal degrees measured from North. Thus 0 will be a section which heads north from the specified location and 90 is a section which heads east from the specified location. An azimuth of +/-180 gives a section which heads south from the specified location and an azimuth of -90 gives a section which heads west.

The actual X and Y coordinates read from the data file are converted to oriented distance from the specified starting point along the section. The displayed portion of the section can be controlled by changing the minimum and maximum X values on the Area Limits, Scale and Projection form, but the values need to be specified as oriented along line distances rather than the actual X,Y coordinates defined.

Similarly the depth limits can be controlled using the minimum and maximum Y values on the Area Limits, Scale and Projection form. These values specify the range of the Depth Variable values to be plotted.

Section Width

This field specifies the distance on either side of the section line within which drillhole data is to be displayed. If the value is zero, all drillhole data read from the file will be displayed. If the value is greater than zero, only those xyz values within the specified distance of the specified section line will be displayed.

Display Data Range button

Once the coordinates and required data variables have been defined, you can check the range of data values contained in the file by clicking on the Display Data Range button. Clicking on this button brings up the Data Range Menu. When this button is clicked for the first time, the currently selected data variables are read from the file and stored in a temporary binary file to speed future access to the data. This temporary file will be retained for the current WinDisp session or until it becomes invalid through a change to the data variables chosen or the line variable, so it is recommended that all data of interest are selected on first entering the Data Specification menu.

Define Data Variable

After specifying the coordinates and required data variables and the area limits and map scale, the parameters determining how the individual data values will be posted need to be specified. This is achieved by clicking on the Define Data Variable button. This will bring up the parameters for the currently selected line in the data definition grid, or the first variable specified in the grid if there is no currently valid selection. Clicking on the Define Data Variable button brings up the following form:

Data Variable

This displays the user name of the currently selected data variable.

Baseline Value

This value specifies the minimum data value for which the data bar will be displayed. If the data value is less than the minimum no bar will be displayed at that position on the drillhole trace.

Scale

This value represents the scale used to convert the data value into bar length. The value is interpreted as units/mm and so can be either positive, zero or negative. If the scale is zero, then only the drillhole trace will be displayed. If the scale is non-zero, the length of the bar plotted is computed using the formula:

length = ( max(value,minimum) - minimum ) / scale

If the computed value is positive, the bar is plotted to the right of the drillhole trace (in the oriented section). If the value is negative it is plotted to the left.

Null Value

This text box displays the null data value for the current data variable, this value is provided for information only and the null data value should be changed on the Specify Data Names menu

Logarithmic Scaling

This value is currently ignored.

Number of Decimals

This value is currently ignored.

Fill Style

This index specifies the type of fill to be applied to the bar for the currently selected data variable. A value of -1 indicates that no fill pattern should be used, a value of zero indicates that a solid fill, and values greater than 1 select various type of hatching fill patterns.

Fill Colour

This box displays the pen colour which will be used to display the perimeter and interior fill for the currently selected bar. In addition if the bar length is larger than the specified maximum radius the data value will be posted using this pen colour. If the colour needs to be changed, click on the colour box to bring up the Pen Colour Specification Menu.

Posting Preview Window

In the lower part of the Post Variable Definition menu is the Posting Preview Window. If the current display area limits and map scale are defined and valid, this window displays the currently defined posting style. As the posting specifications are changed, the suitability of the choices for the parameters can be checked by clicking on the Redraw and the Next and Previous buttons. The x, y and data values are also displayed in the text boxes on the right of the preview window.

Selected Data Variable Drop-down Box

At the bottom left hand corner of this form is a drop-down box containing a list of all data variables currently specified in the data definition grid. By selecting each of the data variables in this list, the parameters defining the posting of each data variable may be specified without returning to the main form.

Finally the Display Data Range menu is accessible from this menu by clicking on the Display Data Range button at the bottom of the screen.

Sample Data

Drillhole data and csf files (15KB)

Single Section

Multiple Sections