abem Terrameter LS, Инструкция по эксплуатации

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ABEM Terrameter LS
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5 Measurement Preparation
5.1 Save Field Time by Doing the Right Preparations
Look through archive material for the area (topographical maps, geological maps,
aerial photographs, reports etc.), and consider whether resistivity surveying is a
suitable method for the current problem. If so, select possible profile lines.
Walk around the area to be surveyed with maps and/or aerial photographs at hand
(aerial photographs and a pocket stereoscope is often highly useful) to select the
optimal profile lines. Walk along the entire length of the planned profiles before
putting out any equipment, to ensure that the selected lines are practical.
Poor electrode contact is the most common reason for bad data. Bring suitable
hammers for installing the electrodes in the field, for instance polyurethane (PUR)
covered hammers that give good force without damaging the electrodes. It is also
often necessary to water the ground around the electrodes, sometimes with addition of
salt and sometimes a substance to make the water stay in place during measurements
(for instance drilling polymer or bentonite). In cases with paved surfaces it may be
necessary to drill holes for inserting the electrodes.
Electrical installations and grounded metal objects may disturb the measurements and
create noise, be observant and take notes of possible sources of disturbance.
5.2 Preparing Data Acquisition
5.2.1 Create Projects and Tasks
In order to prepare for data acquisition at least one Project with one or more Tasks
must exist. Chapters 3.6.1 Project and 3.6.2 Task explains how to create Projects and
Tasks .
Alternatively measurements can be added to existing Projects and Tasks .
All data from a Project is saved in a single database file. It is recommended not to
make the Project too large as it may become cumbersome and slow to handle. In large
data acquisition campaigns it may be suitable to make a new Project for every day in
the field.
Also see chapter 6.11 Full Waveform Data for more information about large amounts
of data.
5.2.2 Data Acquisition Settings
Data acquisition settings are controlled within the “Settings” Menu Item , under which
there are three Views : “Receiver” , “Transmitter” and “IP Window Settings” .