Getting started

This short tutorial introduces you to the basics of a complete ERTdesign project through 3 quick steps.

Set the main survey parameters

The first thing to do to start working with ERTdesign is to define the survey area. The most convenient way to do this is to draw a profile or area - a polyline or polygon - in Google Earth TM and then to import the related KMZ or KML file. Don’t worry, however, if you miss a defined working area and you just need to perform a generic modeling task: ERTdesign allows you to define simple layouts from interface.

Select the Survey Design icon of the Menu Bar to the left of the screen and set the configuration parameters in the corresponding panel.

Survey design panel.

Fig. 2 Survey design panel.

  • In the Survey area section select the KML or KMZ file containing the area for the design project. The layout of the area to be investigated will be shown on the map of the Survey design summary tab (Fig. 3). Then define the desired depth of investigation in the corresponding text box.
  • In the Receivers section, set the spacing for the receiving electrodes of the V-FullWaver boxes. The geometry of the electrodes is defined for each box in a reference system local to the P2 electrode.
  • In the Run Generation section click on the Run arrow to generate the total set of receivers and transmitters. Appropriate advanced settings allow you to make more flexible the sensors generation.

Check and modify the survey project

You can analyze the details of the design project through the 3 main tabs of the software.

The Survey design summary tab shows the details of the set of sensors: the total number of V-FullWaver boxes needed to cover the survey area, the total number of receiving and transmitting electrodes, the total combinations of transmitting dipoles. This information is accompanied by a figure with the map of the sensors, which can be easily zoomed, panned or saved to file.

Survey design summary tab.

Fig. 3 Survey design summary tab.

The DOI/Vmn charts tab allows you to display plots of the maximum sensitivity and depth of investigation for different combinations of receiving and transmitting dipoles (left in Fig. 4) and to check how the Vmn signal changes when the background resistivity or the input current is modified (right section in Fig. 4).

Plots with maximum sensitivity, depth of investigation and expected Vmn signal.

Fig. 4 Plots with maximum sensitivity, depth of investigation and expected Vmn signal.

In the TX/RX schedules tab you find the sheets with coordinates of the generated transmitting and receiving electrodes and with the details on quadrupoles. In the bottom part of the tab you find the graphs with the measurements pseudo-plot and sensitivity plot for each quadrupole.

Tab with sensors schedules and pseudo-plots.

Fig. 5 Tab with sensors schedules and pseudo-plots.

The analysis of the above parameters allows you to eventually redesign the survey, by modifying one or more parameters of the design panel, and to re-evaluate the project.

Save the project

Select the Load and save icon of the Menu Bar to the left of the screen to access the panel with the saving functions.

Load and save panel.

Fig. 6 Load and save panel.

The Save Project command allows you to save three files with the project details:

  • the KML file contains the locations of all sensors (V-FullWaver box, receiving and transmitting electrodes, survey area). You can open this file in Google Earth TM , edit it and import it again into ERTdesign using the command Load project to check how signals and sensitivities change with the new geometry of the electrodes.
  • The DATA file contains the complete list of electrodes and quadrupoles. You can use this file to perform modeling tasks within the ERTLab64 TM and ViewLab3D tools.
  • The TXT file contains the full configuration used to generate the project. You can open this file to reload the settings for a new survey design.

The Export TX spreadsheet command allows you to save a HTML document to be used on site to keep track of transmitting activities, in order to control every step of the survey.