Gaiacode has just delivered 42 seismic broadband sensors of the Alpha Light family and the same number of 24-bit digitizers of our Tau product line to a customer in China. There these complete seismic recording systems will be used for a variety of mostly temporary and portable deployments. The projects in which these instrument sets will be used cover both fundamental Earth Science questions as well applied research topics, like the exploration for energy and mineral resources. Among others it is planned to use the Alpha Light - Tau instrument combination in the high altiudes of the Tibetan Plateau to investigate its deep crustal structure.
Truly Rugged Seismometers
The Alpha Light sensors are a derivative of our flagship Alpha family of seismic sensors. While both instruments are designed to have a flat and repeatable frequency response over the whole seismic band, the Alpha Lights delivered for this project have a flat repsonse from 60 sec (0.0166Hz) to 150 Hz. The sensor noise level of these instruments crosses below the New Low Noise Model (NLNM) in the frequeny range from 18 Hz to 45 seconds. The field worthiness of Alpha Lights is underlined by the fact that they are truly portable rugged seismometers with a power consumption of less than 1 Watt. They can operate within ±5.0 degrees of tilt and can be centered remotely through microprocessor controlled circuitry.
The equipment just delivered to China and the Gaiacode assembly team
The analogue output from the seismic sensors will be digitized in Gaiacode's newly developed Tau digitizer. In addition to the 8 high precision 24 bit main digitiser channels, there are a further 6 analogue input channels to monitor the station and other environmental parameters. The digitizers can produce two separate data streams, one generated by an acausal, the other generated by a causal FIR filter. The digital data are stored on-board and can be easily retrieved by swapping a large capacity micro-SD-Card.
The seismic instrumentation is conveniently packaged in a small pelican case, including a 10 m long seismometer cable, a GNSS receiver with a 15 m long cable. This compact rugged packing solution makes the deployment operation easier even under detrimental environmental circumstances.