Resix
RESIX v3
1 D Forward and Inverse Modeling of DC Resistivity
General
RESIX is an interactive, graphically oriented, forward and
inverse modeling program for interpreting resistivity sounding data in terms of a layered
earth (1D) model. Sounding curves can be entered as a function of a for Wenner or
polepole soundings, AB/2 for Schlumberger soundings, R for dipole soundings or N for
dipoledipole or poledipole soundings.
Sounding curve values are entered as apparent resistivity as
a function of spacing. Forward modeling enables you to calculate a synthetic resistivity
sounding curve for a model with up to ten plane layers. Resistivity sounding curves are
calculated using linear filters.
Shifting of data with overlapping curve segments is handled
automatically by shifting the synthetic curve to match the offsets between segments in the
data. This is done by assuming the data for the longest spacings is correct and shifting
segments at shorter spacings to meet the data at longer spacings. Alternatively, you can
shift the data curve itself to meet either the longest or shortest spacing segment. This
can be done either automatically or manually in the interactive graphics mode using the
Shift Segments option.
Masking of data is achieved in the interactive graphics
interpretation module by pointing and clicking on data points. These points can be
unmasked or deleted according to the users needs. Masked points do not influence the error
or inversion calculations. Interactive model input via the mouse allows the user to see
changes in the calculated curve as he enters the model graphically. Graphic entities of
the plate output may also be resized and positioned using the mouse.
Inverse modeling allows you to obtain a model that best fits
the data in a least squares sense, using ridge regression to interactively adjust the
starting model parameters. You can constrain some of the starting model parameters so the
inversion will not adjust them. Starting models for inversion can have up to 8 layers.
Forward models can have as many as 10 layers. Constants can be applied by fixing (or
freezing) a parameter, or by imposing limits on a parameter. Parameters can be resistivity
thickness of layers, or resistivity/depth to bottom of layers.
Results from forward or inverse modeling can be directed to a
printer or plotter for report ready, hardcopy output. Results can also be saved in a
binary random access disk file for later retrieval. Inverse modeling can be carried out in
an unattended batch mode. Resix provides several options to present the observed data, the
theoretical (forward) data, and the geoelectrical model section used to calculate the
forward response. This information can be graphically presented individually on a dot
matrix printer, a laser printer, or a pen plotter. You can also print the data and model
section in a tabulated, paginated form directly to a text printer.
Data stroage is handled by a new data base file format that
holds up to 200 data sets (or sounding curves). This size of the file depends on the
number of sounding cureves it contains.
Standard Components
Resix v.3 software and instruction manual.
