Enter channel survey
This function enables you to enter observations, bearing, dip and distance data, to locate strings representing channel sample strings in preparation for displaying in the Graphics module. You can then edit the strings to ensure the correct position for later loading to the Geological database.
To run this function: Choose Design > Grade control > Enter channel survey, or...
The channel samples are represented by a string of a single segment where each of the samples in the channel are represented by successive pairs of points in the string. The channel strings may be located relative to a Survey Station selected from the Survey Database, or relative to a known co-ordinate, even though it may be approximate. It is permissible to define the initial location relative to an approximate position. During the editing phase it is then possible to recall files of mine workings and adjust the position of the channel strings so that they are correct in relation to the mine workings.
If the channel strings are to be located relative to Survey Stations then you must ensure that you are already connected to a Survey Database. If you wish to locate the channel strings relative to an approximate position, i.e. X, Y, Z co-ordinates, then you should use the CLOSE SURVEY DB function if you are presently connected to a Survey Database.
Channel ID
Enter the channel identifier. This will be used when the channel data is loaded into the Geological Database for future reference. It is important that this name is not already present in the database.
Define the Channel reference point
Station ID and H.I.
These two fields will only be present if you are connected to a Survey Database. If these fields are displayed then you MUST enter the name of a station which exists in the survey database. After entering the Station ID and pressing enter, the database will be queried to retrieve the co-ordinates of the station. If the station does not exist an error will be displayed and you must re-enter the Station ID. If the station exists, the co-ordinates will be displayed in the adjacent Y, X and Z fields.
The H.I. is the height of instrument from the station mark to the point at which the Dip, or inclination from the station to the channel start point was measured. The convention for Height of Instrument is: distances measured down from the station are negative and distances measured up from the station are positive.
Y, X and Z
If you are connected to a Survey Database then the co-ordinates of the Survey Station will be displayed here, otherwise you must enter the co-ordinates of the point from which the bearing and dip to the channel start point were measured.
Note:Even if you are connected to a Survey Database, it is still permissible to alter the Y, X and Z values in the event that you were offset from the station position by some distance. Changing the co-ordinates does not effect the co-ordinates of the station in the database but it does guarantee that adjusted position will be used to calculate the co-ordinates of the channel string.
Define the channel start position Bearing, Dip and Slope Dist
The channel start position must be defined relative to the co-ordinates described above by entering the Bearing, Dip and Slope distance from the reference co-ordinates to the start of the channel. The convention for the DIP is that values > 0 are ascending while values < 0 are descending with 0 = horizontal lines of sight.
Note: Bearings and Dips must be entered in decimal degrees.
Define the channel orientation and length
Bearing, Dip and Sample range
The sample orientation must be defined by entering the Bearing and Dip to describe the orientation of the channel string. The number and lengths of samples in the channel string are defined by entering a range of sample end points.
Note: Bearings and Dips must be entered in decimal degrees.
To explain further, each sample within the channel is represented by successive pairs of points where the position of the second and successive points in the string are defined using a range. The range indicates the distance from the start of the string along the entered bearing and dip to the point of interest. You must ensure that the sample length range DOES NOT start with 0 (zero).
Calculations are performed using the entered observation data to create the strings which represent the channel samples. Each of the strings representing the channels are then drawn to permit you to edit the channel strings to ensure that the strings are correctly positioned relative to the mine workings, prior to committing the channel strings to the Geological Database by using the LOAD CHANNELS TO DATABASE function.
Each of the channel strings has the channel ID in the description field of the first point of the channel and the sample range in the description field of the last point of the string. This has been done deliberately as the LOAD CHANNELS TO DATABASE function is expecting the strings to contain the data in this manner.
The strings may be edited using any of the available Graphics edit functions, including the TRANSFORM CHANNELS function to ensure that the position with respect to surveyed mine workings is correct. To assist in this editing files may be recalled into other Graphics Layers as editing aids.
The strings may also be saved to a string file if necessary. Further editing can then be done later if it is not possible to complete the loading into the database at this time.
It should be further noted that the appearance of the strings for the displayed channels are defined in the Draw Styles file. If there is no Draw Styles file defined in the Default Preferences, then the channels are drawn as default lines.