“Survey Design” panel

The “Survey Design” panel (Fig. 11) allows to manage the multisource survey project, by defining the survey area, the configuration of transceivers and the combinations of transmitters.

Survey design panel.

Fig. 11 Survey design panel.

The panel is made of five sections and the configuration parameters are usually specified following a top-to-bottom order.

“Survey area” section

Contains the commands to define the layout of the area or profile to be investigated. In the drop-down menu you can choose between two options.

1. Load from KMZ/KML file

Opens the dialog to select a KML or KMZ file with the area (polygon) or the profile (polyline) for the project design. If multiple graphic objects are stored into the file, only the first occurrence will be taken into account. The layout of the survey area will be shown on the map of the Project summary tab. The map makes use of UTM coordinates, with conversion based on the ellipsoid defined in the Preferences panel (default is WGS84).

2. Define the survey area geometry

When a KMZ or KML file is missing, use this command to access the Define survey area panel to generate simple linear or rectangular survey geometries.

“Transceivers” section

In this section it’s possible to specify the total number of boxes to arrange in the two directions and/or the spacing of the electrodes for each device.

  • If only the total number of boxes is specified, the electrode spacing is automatically derived and vice versa.
  • If both parameters are defined, the tool stops the sensors generation when reaching the specified number of boxes, which can lead to cover only partially the survey area.

Use the X (max side) textbox to specify the number of boxes in the direction of the survey area with the major extension. Use the Y (min side) textbox to specify the number of boxes in the direction of the survey area with the minor extension.

The geometry of the electrodes is defined for each box in a reference system local to the P2 electrode, which has always (0.0, 0.0) coordinates. The logic of the P1-P3 electrodes arrangement is based on the following convention:

  • the x axis of the local reference system is aligned along the direction of the survey area with the major extension;
  • the y axis of the local reference system is aligned along the direction of the survey area with the minor extension.

For example, setting P1 coordinates to (-15.0, 0.0) and P3 to (15.0, 0.0) will arrange the three electrodes along the direction of the survey area with the larger extension, as displayed in Fig. 12.

Transceiver geometry aligned along the larger area dimension: P1(- 15.0, 0.0) and P3(15.0, 0.0).

Fig. 12 Transceiver geometry aligned along the larger area dimension: P1(- 15.0, 0.0) and P3(15.0, 0.0).

Setting P1 coordinates to (0.0, -15.0) and P3 to (0.0, 15.0) will arrange the three electrodes along the direction of the survey area with the minor extension, as displayed in Fig. 13.

Transceiver geometry aligned along the smaller area dimension: P1(0.0, -15.0) and P3(0.0, 15.0).

Fig. 13 Transceiver geometry aligned along the smaller area dimension: P1(0.0, -15.0) and P3(0.0, 15.0).

Similarly, setting P1 coordinates to (15.0, 0.0) and P3 to (0.0, 15.0) will arrange the three electrodes according to an “L-shaped” geometry, with alignment of P1-P2 along the direction of the survey area with the larger extension, as displayed in Fig. 14.

"L-shaped" geometry for transceivers with P1(15.0, 0.0) and P3(0.0, 15.0).

Fig. 14 “L-shaped” geometry for transceivers with P1(15.0, 0.0) and P3(0.0, 15.0).

Any other combination of coordinates is allowed in order to create dipolar geometries of any kind.

“TX combinations” section

In this section you can define how many transmission dipoles you want to use, based on two distribution modes: alignment of the dipoles along a given direction or parallel arrangement (side-by-side spread of TX dipoles).

  • Insert in the TX in-line textbox the number of aligned TX dipoles to be used.
  • Insert in the TX cross-line textbox the number of TX dipoles to arrange parallel between adjacent lines. This option is only available if the multisource boxes are distributed over areal geometries.

“Advanced Settings” section

The specific section with the advanced settings allows to perform more flexible generations, by modifying configuration parameters of both transceivers and transmitter combinations.

Run generation

Once the survey configuration parameters have been defined, it is possible to proceed to project generation by clicking on the “Run” arrow icon of this section.

The generate transceivers only checkbox performs the simple generation of sensors and skips the n-poles sequence generation.

Note

The “generate transceivers only” option is strongly recommended at the first generation of the project, in order to quickly check the distribution of the transceivers on the survey area and compare the design results with the area coverage needs and with the total number of Multisource boxes available in the field.

Once a satisfactory distribution of the transceivers has been defined, it will be possible to proceed to a new generation that excludes the “generate transceivers only” option and produces the global set of measurements to be acquired.