GSSI SIR 4000, Manual

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Geophysical Survey Systems, Inc. SIR® 4000
Manual
MN72-433 Rev F 117
Step 4: Set Grid Limits
Under the Grid Menu, set your grid limits, line
spacing, and orientation.
Start/End Values:
Typically, the X Start Value
and the Y Start Value should both be set to 0. If
the grid does not start at (0,0) put in the
coordinates of the origin point. This occurs when
the grid is part of a larger site grid, or you are
surveying along a previously-established grid. If
combining grids in RADAN using Super3D, you
can just leave this number at (0,0) and add real
coordinates later. Enter your X End Value and Y
End Value coordinates and remember that these
are not line lengths.
In the example below, the grid measures 10m x
10m. Its starting coordinates are X Start Value =
0 and Y Start Value = 0, therefore the X End
Value = 10 and the Y End Value = 10.
Line Spacing:
If collecting data in both the X
and Y directions then include line spacing in each
direction. If only collecting in one direction then
only include line spacing for the direction in
which you’re surveying and set the other to the maximum overall grid dimensions.
Line Order:
Decide if you’re going to collect the lines using Forward, Zigzag, or Reverse Line Order.
Forward and Reverse will take longer to collect. However, these have potential for fewer offset errors
created by an uneven ground surface or a slightly misshapen grid. Potential offset errors created by
collecting in Zigzag can be corrected in RADAN.
Step 5: Enter Collection Screen
Once you are satisfied with the grid and settings press the green Start button on the SIR 4000. This will
open the 3D Collection Screen. Once in the 3D Collection Screen you will have access to three menus:
Process, Output, and System. These are explained below. There are also four different ways to view the
2D profiles and 3D slice maps during collection and you can toggle through them by pressing the View
Toggle control button.
Grid Display:
Shows the full 3D grid and your current grid location. There are three possible views.
2D Profile:
Shows just the 2D profile and can be used to perform a hyperbola fitting on the data. This
view is only available from Line 1.
The grid coordinates are displayed at the bottom left and top right corners of the grid. The X and Y line
lengths appear on the bottom and left side of the grid. At the top of the screen the following appears:
•
Total number of lines
•
Number in both the X and Y directions
•
Estimated file size
•
Current Slice Depth and Slice Thickness