ABEM Terrameter SAS 1000 / SAS 4000
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GENERAL
The Terrameter SAS system consists of a basic unit called the Terrameter SAS 1000 or SAS
4000 which can be supplemented as desired with accessories such as the ABEM LUND
electrode systems and the ABEM SAS LOG 300 borehole logging unit. This manual covers
the operation of SAS 1000 and SAS 4000 as well as these accessories.
SAS stands for Signal Averaging System - a method whereby consecutive readings are taken
automatically and the results are averaged continuously. SAS results are more reliable than
those obtained using single-shot systems.
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SAS 1000 / 4000 can be used for resistivity surveys, IP surveys and self-potential surveys.
•
The ABEM LUND system is an automatic electric imaging system, suited for automatic
resistivity, IP and SP profiling.
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The SAS Log 300 (optional) provides an efficient, simple way of extending your survey
into wells and drill holes. It consists of a 300m cable with logging probe, electrodes,
temperature transducer, water level indicator and resistivity cell, all mounted on a
backpacking frame.
The applicability of the different resistivity and IP methods supported by the SAS 1000 /4000
is summarized in table 2-1 below.
Object of search or investigation
SP
VES
Imaging
IP
Archeological sites
x
Cavities in subsurface
x
Clays, peat and soil
x
x
Dam safety and leakage
x
(x)
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Fissures in rock
x
Fracture zones in rock
x
Groundwater in crystalline rock
x
Groundwater in sedimentary areas
x
x
Groundwater / clay distinction
x
x
Groundwater flow
x
Ores in hard rock areas
x
x
x
Overburden thickness
x
x
Pollution of soil and groundwater
x
Saltwater invasion
x
x
x
Waste mapping / characterisation
x
x
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Monitoring.
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Parasnis, D. S., Principles of Applied Geophysics, 5 edition, 1997. Chapman & Hall.
Table 2-1: Applicability of different resistivity and IP methods. Modified from Parasnis
(1997)
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. SP=Self Potential, VES=Vertical Electrical Sounding, Imaging=Profiling
(with different electrode separations), IP=Induced Polarization.