Low Power Long Period Magnetotelluric System
Abstract
We have constructed a new MT system for periods longer than 1 second that uses substantially less power and is considerably easier to deploy than predecessors, such as the Geological Survey of Canada [GSC] Long Period Intelligent Magnetotelluric System [LIMS]. Technical aspects of these new systems include: Fully watertight; light weight [5 kg w/o magnetometer head], Eurocard card cage, 1.7 watt power consumption - 140mA @ 12vdc, built-in solar panel charge controller, GPS-disciplined timekeeping accurate to 1ms, 24-bit 8 Hz Analog to Digital conversion, data storage on a PCMCIA flash disk [85M and up], magnetic field: +/- 80,000 nT range with 10pT resolution, electric field ch: +/- 200 mv with sub-microvolt useful resolution. A setup program automatically handles most deployment tasks including recording site location and data start time. Data are logged in files that begin at hour marks and are of one-hour duration. They are thus automatically synchronous at an array of instruments. Data retrieval consists of moving a PCMCIA card from the data logger to a laptop computer. A revision of this system is already in progress. It will feature PC104 card formats and will be lighter, smaller and have even lower power consumption. Ten of these systems were deployed for the first time during August and September 2001, in Argentina. Sample data from these deployments will be shown.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2001
- Bibcode:
- 2001AGUFMGP21A0247N
- Keywords:
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- 0694 Instrumentation and techniques;
- 0925 Magnetic and electrical methods;
- 0994 Instruments and techniques;
- 1515 Geomagnetic induction;
- 1594 Instruments and techniques