“Advanced Settings” panel¶
The advanced settings panel allows the user to define some custom parameters to refine the survey design. Settings are divided into two sections, one for the parameters of the receivers and one for the transmitters.
Fig. 16 Advanced settings panel.
In order to make the modifications persistent, it is necessary to click on the arrow-button Apply at the bottom of the panel, which implements the changes e leads back to the main design window.
Receivers¶
The receiver section contains three configuration parameters.
RX sensor spacing¶
The value in the text box represents the distance between successive electrodes of two adjacent receiving boxes, as shown in figure Fig. 17.
Fig. 17 Spacing between the receivers.
When the auto checkbox is selected, the software automatically finds the spacing between the receivers, based on the geometry of the receiving electrodes. For in line configurations of the electrodes, the calculated distance will be equal to double of the width of the largest receiving dipole. In this way the transmitter placed between the two receivers has a distance from each adjacent RX electrode equal to the width of the receiving dipole. For not aligned electrodes the automatically calculated distance will be equal to the width of the largest RX dipole.
In/Out area tolerance¶
Defines the tolerance radius in meters for arranging the V-FullWaver boxes within the survey area and is useful to make the generation of receivers more flexible in case of complex geometries of the survey area. In the example of figure Fig. 18 the modification of the tolerance from 5 meters (a) to 20 meters (b) causes the insertion of five extra receivers to the project, with an extended coverage of the boundaries of the survey area.
Fig. 18 Example of generation of RX for different inside/outside tolerances: a) 5 m; b) 20m.
When the auto checkbox is selected, the software automatically calculates a tolerance equal to 20% of the width of the largest RX dipole.
% of RX getting max doi¶
Allows to configure the percentage of receivers for which the maximum depth of investigation is achieved. The 100% value implies that the algorithm generating the transmitters will try to guarantee the maximum depth of investigation to all receiving dipoles. To meet this requirement on the most external receivers of the survey area it will be necessary to enlarge the extension of the remote transmitters. Setting the parameter below 100% reduces the extension of the transmitters, with the effect of achieving the maximum depth of investigation only in the most central portions of the survey area.
Transmitters¶
Settings in this section refer to constraints on the properties of transmitters.
Max AB length for the TX dipoles¶
Defines the maximum width in meters that is allowed for the transmission dipoles. The preset value is 10 9 meters (infinite extension). Changing this parameter can be useful for planning surveys where impediments, such as the presence of rivers, busy roads, buildings or other, make it difficult laying down long cable extensions for the transmitters. In such situations, it is often preferable to make use of small transmitting dipoles and perform multiple movings of the transmission base in areas favorable from a logistic point of view.
Note
Limiting the AB width of the transmitting dipoles implies that the resulting quadrupoles are mainly of dipole-dipole type, in particular for those TX and RX combinations that are involved in the deeper prospection. As a consequence, at the same depth of investigation, the signal expected at receivers is much lower compared to unconstrained TX acquisition schemes, in which the measuring arrays belong to gradient, Schlumberger or pole-dipole schemes.
Allowed directions for remote TX¶
Inserts limits on the directions allowed for the arrangement of the TX electrodes outside the survey area. The [0, 360] setting indicates that all directions are allowed. In the example of figure Fig. 16 the setting allows the arrangement of remote TX only in the sector between 0 and 45 degrees of azimuth North and in that between 180 and 315 degrees of azimuth North.
The user can specify different sectors of the quadrant in which the arrangement of TX electrodes is allowed. The correct notation for definiing a list of sectors is made by comma separated elements (,). Each element is defined by the list of the two angles (minimum and maximum) enclosed in square brackets:
[alfa1, alfa2], [alfa3, alfa4], ...