DC2DInvRes - Show Menu


The model display shows the resistivity of the model section. There are a lot of options for that descibed in the options menue. By clicking on model cells the cell boundaries and the resistivities are displayed. This mode can also be used for interactive modelling by typing a resistivity value into the edit window and clicking on model cells or drawing ragged boxes.

Hotkey: Shift+M


The Coverage is defined by the sum of the (absolute values of) sensitivities over all measurements and can be displayed like a model section.

In analogy to ray path tomography it's something like total raypath and gives information on how well the model cells are "covered" by the data set. It is used for alpha mapping the model section to avoid over-interpretation of anomalies in bad covered regions such as near the model boundaries.


Furthermore, it is possible to display the sensitivity for every single datum point. A positive sensitivity(red) leads to an increased apparent resistivity when the cell resistivity is rised, negative sensitivity(blue) lower the apparent resistivity. The measurement is insensible to regions of zero sensitivity(white).
Regarding this we have a first concept of detectability and resolveability of underground structures.

By moving the slider (or typing datum number) we can switching to all data points.

Display data points

To display the complete data set it is useful to plot every datum point with a single block. The following section shows a dipole-dipole dataset (21 electrodes, a=2m) dipole length as a function of midpoint (x) and separation (dipole distance by dipole length).

By clicking on a single datum point a dialog shows its electrode positions and the measured resistivity. The user is able to delete this datum point clicking on "yes".

Hotkey: Shift+D


In the same manner as for plotting the data one can display the (measured or estimated) standard deviations of each datum point.

Forward Response

The forward response of the current model ist diplayed in the same way like the data.

Hotkey: Shift+R

Data Misfit

Watching the data misfit (difference between datum point and forward response in percent) it is possible to see how the data are fitted by the model. Ideally, the data are fitted giving a misfit of gaussian errors showing no significant function of space.

Misfit per Error

To estimate, how well the data are fitted, the misfit is divided by the standard deviation and plotted.
Ideally, the misfit per error is (again) randomly distributed and near +/- 1 at the end of inversion process.

Compare data

To have an overview on fitting the data it is useful to see data, forward response and misfit in one window. Data points and forward response are plotted using the same colorbar. The plots are placed in a seperate window, which keeps updated if the model (and thus its response) is changing. It is recommended to create the window at the beginning of the inversion.

Hotkey: Shift+C


If present, the measured (or in the error GUI estimated) voltage (absolute) is displayed in data type (logarithmic colorbar).


If currents are present in the data, they are displayed in mA with log-scaled colors.

IP Data

If the data file contains IP data, they can be displayed and used for inversion of chargeabiliy.

IP Model

Once a chargeability model has been derived by the IP data, it can be displayed.

Compare IP data

In the same way we look at data, model response and misfit we can fo for ip date after running the ip inversion.