50 years of global seismology: USGS Albuquerque Seismological Lab

GSN ANSS The WWSSN  100+ analog station network  Provided data for monitoring nuclear tests and seismological research  Contributed to fundamental observations to plate tectonics

GSN ANSS GSN

ANSS Iceland KNTN - Kanton Island KOWA - Mali SAML - Brazil QSPA - South Pole Station examples ENH - China

GSN ANSS Then and now Shallow seismic vaults

GSN ANSS Then and now System assembly

GSN ANSS Then and now Repair and testing

GSN ANSS Then and now Instrument shop

GSN ANSS Then and now Instrument testing

GSN ANSS Then and now Data Quality Control

GSN ANSS Instrumentation Wish List Low power  Locations are often very remote Light weight  Carrying heavy equipment long distances makes field engineers grumpy Modular  Useful to be able to send individual components Remote diagnostics  Improved tools for troubleshooting sensors & data acquisition units And …. inexpensive (Budgets are tight!)

GSN ANSS Instrumentation Wish List Observational capabilities - sensors GSN requires very broadband, low noise sensor  360 s to 50 Hz  Below GSN low-noise model to 10 Hz Currently use two sensors to cover the band of interest  Increases expense … but provides a backup Some options for vault sensors on the horizon Need improved borehole sensor performance

GSN ANSS Exciting developments Metrozet surface vault sensor Quanterra STS-2.5 deployed in a borehole UCSD iSeis

GSN ANSS Instrumentation Wish List Observational capabilities – dataloggers Option for 9- and 12- channel systems Wider range of calibration frequencies Robust telemetry support  Including TCP/IP  Developments with Linux boxes are interesting … but may create IT security issues 4 Q330s at QSPA

GSN ANSS Instrumentation Pet Peeves Cables and connectors Reduce leakage  Need better sealed connectors Improve reliability  Recent experience with a spate of bad cables (manufacturer-made) Increase flexibility  Many cables are extremely stiff Thoughtful connector location  Some locations are better for borehole/post installation; others for surface sensor

GSN ANSS Instrumentation Pet Peeves Sensor orientation/leveling Ease of orientation  Many different approaches: rods, feet, alignment pins –Success depends on application  Some are easier than others – standardization desirable  Add a North-finding capability (export allowable)? Manufacturers need to specify accuracy: –Of axis orientation with respect to marks on the case –Of vertical orientation when the leveling bubble is centered

GSN ANSS Instrumentation Pet Peeves Accuracy of sensitivity & transfer function Manufacturers should specify accuracy  We have found problems with a number of sensors! Retrievable parameters Manufacturer name, model number, serial number, and factory calibration parameters sufficient to reconstruct the sensitivity and transfer function of that particular sensor and/or data acquisition unit