1. Global Seismograph Network - GSN: IRIS -2 System

DATES OF OPERATION: 25 Aug 2001 to Present.

SEISMOMETER TYPE AND ADC:
Geotech KS54000 borehole seismometer for broad-band channels (00 location
code). Guralp CMG3-T-B borehole seismometer for higher frequency broad-band
channels (10 location codes). Kinemetrics FBA-23 Low-Gain sensor (20 channels).
ADC Quanterra Q-680, 12 channel system.

DIGITAL FORMAT:
24 bit integer data words for all broad-band (20 sps), long period (1 sps), very long
period (0.1 sps), and ultra long period (0.01) channels. Range: +8,388,607 to -8,388,608
counts.

EVENT DETECTOR ALGORITHM:
The Murdock/Hutt event detector (Murdock, 1991) is used for the HN? and HH? channels.