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ReflexW 2D GPR Data
Analysis Module

Example of the point mode display of 2 different
GPR-lines and the additional magnifying zoom option
GPR (Ground Penetrating Radar)
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Reflection Seismics
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Refraction Seismics
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Borehole-Borehole Wave Data
REFLEXW is the new WindowsNT/9X/2000
software generation of REFLEX for the 2-dimensional
processing and interpretation of Ground Penetrating
Radar (GPR), reflection and refraction seismic.

Example of the wigglemode display
of a seismic refraction section

Example of the plot options panel
This 2-D GPR Data Analysis Module
described below can be upgraded to perform 3-D Data
Interpretation
2D data-analysis
Import data
An import option allows the loading
of the data for almost all existing GPR and seismic data
formats. Single sections as well as a profile sequence
(automatic assembling and storing of the sections under
one single datafile or automatic generation of datafiles
for parallel and inline-sections) may be imported
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Display of the data either in
wiggle (see right figure above) or filled area point
mode
"Normal" reflection (time axis from top to bottom)
or refraction (time axis from bottom to top) display
Continuous display of the current mouse position
parameters including time, distance, amplitude and
depth
Zoom- and autoscroll possibilities
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Loading of a secondary profile,
horizontal or vertical split-mode or overlapping of
the profiles ==
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The user may switch between two
different scale modes:
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The data are completely
plotted into the actual window with subsequent free
zooming and moving possibilities
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Trace based scale: the user
chooses the pixel size for each trace. If the line
is not completely plotted into the window moving
possibilities are available
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Interactive magnifying glass
option (see left figure above) with choosable zoom
factor - a freely choosable data part is
continuously magnified when moving the mouse
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Interactive color amplitude
assignment for point mode - display of the profiles
in the point and wiggle mode
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Many different plot options,
e.g. rotated display, combination of wiggle and
point mode, free choosable axis and so on (see
central figure above)
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Easy transfer of the data to
the clipboard
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Printing out the data with
freely choosable scale either in cm or scale like
1:1000; support of banner output (continuous
printing on printers which support banner output,
e.g. HP Deskjet 1120 C)
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Stack printing of a complete
set of 2D-lines using the same printing parameters
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Oscilloscope-function - wiggle
plot of the actual trace with the indication of the
actual amplitude, time and frequency
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Comprehensive context sensitive online help
The data processing
possibilities
A single radargram or seismogram
section can be interactively processed. Primary and
secondary profiles are displayed simultaneously. The
batch mode allows the automatic processing for a
choosable number of lines. A sequence of processing
steps will be applied on an arbitrary number of
profiles. The batch mode runs totally automatically.
Primary and secondary profiles will be displayed,
whereby a direct control of the result is given. All
processing steps are stored for each profile and can be
edited at any time. The data processing is completely
interactive. The effect of the filter is online
controlled when changing the filter parameters by
showing both the original and filtered trace. All edit
inputs may be entered either interactively in the
original profile or using the table input.
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| Example of a processing function panel |
Example of a 1D-filter panel |
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An overview of the different
processing functions:
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Editing functions (like
removing, extracting of single traces/trace ranges,
muting, stacking, subtracting or adding of profiles
and much more).
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Horizontal scaling of the data,
automatically or manually or by a combination of
both.
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Flipping the profile in
x-direction or y-direction.
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Static correction (interactive
input of the correction values, slant stack
correction and so on).
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Gain-functions in horizontal
und vertical direction, AGC (Automatic Gain
Control), automatic trace balancing, linear and
exponential gain function, automatic gain based on
mean amplitude decay curve (see left figure on page
2)
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A great variety of 1D-filters
like bandpass, notch-filter, time dependent bandpass,
cross-correlation, arithmetic function, averaging,
median-filter, deconvolution, complex trace analysis
(instantaneous frequency, phase, envelope),
time-depth conversion, background removal,
declipping and so on.
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Spectral analysis - single
spectra, moving-window-analysis.
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Migration - 2D Kirchhoff, 2D fk-migration,
2D Finite Difference migration with lateral varying
velocities, 3D Kirchhoff.
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Some other 2D-filters like
subtracting average, running average, compress and
expand and so on.
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F-k-filter with the possibility
of manually input the filter range within the fk-
spectrum or by defining a velocity fan.
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Different tapers and taper
width are available.
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and much more possibilities
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All processing steps are stored
in the header of each profile and can be asked for
at any time
Velocity Analysis
An interactive hyperbola-adaptation
for a simple determination of the average velocity from
a zero-offset or CMP profile is integrated. It is
possible to adapt diffractions, reflections and straight
lines. You may change the velocity, the radius of the
target, the angle between the profile line and the
target and the width of the calculated diffraction or
reflection hyperbola. There is also the possibility of
fitting linear features either by changing a line
interactively or by setting two points. The option core
allows to vary interactively the velocities of the
single layers of the individual cores stored within an
ASCII-file. In addition an interactive use of the
intercept time method for seismic refraction data is
included. The option enables to get a first 1D-model
very quickly. The velocities may be stored on file and
may be reloaded at any time. The velocities are combined
into a 2D-model by using a special interpolation. Such a
2D-velocity distribution may be used in a subsequent
step for the migration or the time-depth conversion.

Example of a layer show

Picking of the first arrivals of a refraction data set
Picking the onsets/first
arrivals
The picking option allows to pick
the travel time and the amplitude of different onsets
like reflectors or hyperbola or the first arrivals. You
have the choice between manual picking, continuous
picking and a semi-automatic picking using a phase
follower (manual editing is always possible). The picked
values may be corrected to the extreme or the
zero-crossing. In addition a time/distance correction to
the maximum value within a given window is available.
This allows you for example to pick the hyperbola cusps
very quickly. It is possible to export the picks into an
ASCII-format together with the 3 space coordinates for a
subsequent interpretation. The so called layer-show
offers the possibility to combine individual pick files,
to plot them together with the wiggle-files and to
output them in report form on printer or file containing
the depths, velocities and amplitudes of the individual
layers. The time-depth conversion of the picks is either
based on a constant velocity for each layer or on a
2-dimensional velocity distribution allowing to take
into account vertical and lateral velocity changes.
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