PASI Polares 32, Руководство пользователя

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POLARES 32 7
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The real (in-phase) and imaginary (or quadrature) components of the complex resistivity
can be obtained from the following relationships:
Real resistivity is mainly related to electrolytic conduction phenomena (resistivity of rock
or soil, and even more so to the resistivity of pore-filling fluids), and to various aspects
of induced polarisation (surface polarisation, presence of metallic minerals, contaminants
and so on).
Many studies and works have shown a growing interest in AC geoelectric surveys, which
have demonstrated their effectiveness for mineral exploration, structural characterisation
of geological features and monitoring of contaminated sites.
For users who prefer to work with chargeability as an IP parameter, POLARES32
automatically stores the chargeability (in ms) associated with each measurement, thanks
to the relationships between phase shift (IP in the frequency domain) and chargeability
(IP in the time domain).
- SPEED: POLARES32 can be used to measure single high-frequency data sets (7 to
125Hz). In many common applications, ensuring good electrode-to-ground contact is
sufficient to acquire accurate datasets of apparent resistivity values, ready for subsequent
inversion using special external software.
The higher the frequency, the higher the speed: field data from moderately noisy sites can
be acquired at a rate of up to 3 measurements/second, in any measurement matrix. In
many cases, the time necessary to complete the series of measurements can be reduced
by a factor of 10 to 20 compared to traditional DC systems.
-
ACCURACY: the high resolution of the acquisition system (0.4 μA for current signal
and 1.5 μV for voltage signal) allows accurate interpolation of sin usoidal current and
voltage signals. This becomes even more important when POLARES32 is used for
spectrally-induced polarisation surveys, where phase shift values must be measured with
the highest level of accuracy.
For users requiring noise-free phase data, POLARES32 can be used with non-polarisable
electrodes to avoid any inductive EM coupling along the wires between the transmission
and measurement circuits.
- MODULARITY: POLARES32 contains, integrated in a robust Peli case, the
transmission and measuring system, all the necessary guards and also 2xMPX
(Multiplexer) with 16 electrodes each (for the first 32 electrodes). Additional external