Geoscience Reference
In-Depth Information
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Figure 6.19
Distribution of the electrical potential, recorded at the electrode depicted by the large dot, for each point in the
scanning area. Each point corresponds to the electrical potential recorded at the electrode at the time of focusing
(the reference electrode is supposed to be at infinity). These electrical potential maps illuminate the heterogeneities in the vicinity
of the particular electrode of interest here. Seismoelectric responses that are too far from this particular electrode are too weak
(in a relative sense) to help image those relatively distant heterogeneities.
numerous techniques available to detect the edge, in this
work, we used a simple approach of image sharpening
(Figure 6.21). Once the boundaries are identified, we
discretize the domain between the two wells in
L
×
L
m
cells (based on the electrodes separation of
L
). All cells
that fall within the boundaries are considered to belong
to the same geological unit.
6.3.2.2 Introduction of structural information
into the objective function
We consider again our two vertical wells, A and B,
located 300 m apart with a depth of 1050 m. Within
each borehole, we have electrodes with
L
= 10 m spacing
(105 electrodes per borehole; see Figure 6.22). We simu-
late bipole
-
bipole data (one injection source and one
