Open AccessRésultats d'études théoriques et expérimentales concernant les phénomènes de polarisation provoquée dans le cadre d'applications géophysiques
Author(s) -
David Tournier
Publication year - 2011
Publication title -
annals of geophysics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.394
H-Index - 60
eISSN - 2037-416X
pISSN - 1593-5213
DOI - 10.4401/ag-5106
Subject(s) - depth sounding , analogy , polarization (electrochemistry) , physics , theoretical physics , statistical physics , mathematics , philosophy , epistemology , geography , cartography , chemistry
The present treatise can be subdivided into four sections.
The first is concerned with I. P. phenomena in general, the diverse ways
in which one may study such a phenomenon, the different parameters governing
it or permitting us to define it. A parallel is also drawn between the
induced polarization and resistivity methods.
The second section is essentially theoretical. An effort is made to schematize
as much as possible a certain number of idealized typical cases for
which the polarization produced by the passage of a continuous current may
be calculated with precision, for two- or three-dimensional structures. In
these calculations we assume that the duration of passage of the current is
sufficiently long for maximum polarization to be attained. These hypotheses,
necessarily and voluntarily oversimplified, have no other purpose than to
orient the person who is to interpret the phenomenon in question, to help
him to comprehend the mechanisms brought into play therein hence to
guide him when ho is confronted with the much more complex results yielded
by actual field surveys. One is thus obliged to recognize that despite a
certain parallel between the techniques of classical electrical sounding and
I. P. sounding, the analogy must by no means be drawn too closely. The
overall aspect of the two types of sounding is not at all the same.
Although such calculations are highly useful, there is, none the less, a
world of difference between highly simplified examples and actual problems.
This gives rise to the necessity for an intermediate stage for which only an
experimental study by analogy, carried out on models, can be taken under
consideration.
The third section is consequently experimental and deals precisely with
models
The first is concerned with I. P. phenomena in general, the diverse ways
in which one may study such a phenomenon, the different parameters governing
it or permitting us to define it. A parallel is also drawn between the
induced polarization and resistivity methods.
The second section is essentially theoretical. An effort is made to schematize
as much as possible a certain number of idealized typical cases for
which the polarization produced by the passage of a continuous current may
be calculated with precision, for two- or three-dimensional structures. In
these calculations we assume that the duration of passage of the current is
sufficiently long for maximum polarization to be attained. These hypotheses,
necessarily and voluntarily oversimplified, have no other purpose than to
orient the person who is to interpret the phenomenon in question, to help
him to comprehend the mechanisms brought into play therein hence to
guide him when ho is confronted with the much more complex results yielded
by actual field surveys. One is thus obliged to recognize that despite a
certain parallel between the techniques of classical electrical sounding and
I. P. sounding, the analogy must by no means be drawn too closely. The
overall aspect of the two types of sounding is not at all the same.
Although such calculations are highly useful, there is, none the less, a
world of difference between highly simplified examples and actual problems.
This gives rise to the necessity for an intermediate stage for which only an
experimental study by analogy, carried out on models, can be taken under
consideration.
The third section is consequently experimental and deals precisely with
models