In the third year (10/1/2001-9/30/2002) of ANSS funding the California Integrated Seismic Network (CISN) received equipment to install 30 digital seismic stations in the San Francisco Bay region (see Figure 1). As in the two previous years, the sites were chosen to address two critical seismic-monitoring needs in the region - construction of real-time ShakeMaps and monitoring of strong shaking in urban areas. To improve the ability of the CISN to create ShakeMaps, the USGS Northern California Seismic Network (NCSN) requested instruments to upgrade obsolete analog seismic equipment at 9 existing regional network sites and to install 2 new sites where seismic coverage for ShakeMap was poor. The data loggers for these 11 sites will digitize output from a tri-axial accelerometer (for strong motion) and a vertical seismometer (for monitoring microearthquakes. The remaining 19 sites requested from ANSS are new sites in urban regions of the San Francisco Bay region to be installed by the USGS National Strong Motion Program (NSMP). The urban sites will only have tri-axial accelerometers.
Installation of the equipment was not completed by the end of the fiscal year for two reasons. First, the ANSS procured a brand of datalogger with which the NCSN had little experience. While the dataloggers were received in late June, the final software release was not distributed from the manufacturer until mid October 2002. Thus, the NCSN was unable to begin software Q/C until after the end of the FY. As of the end of the FY we have confirmed that we can successfully record continuous seismic data but have not yet developed software to automatically assess datalogger state-of-health. Even so, the delivery of the dataloggers late in the summer field season conflicted with scheduled NCSN installation/maintenance operations at sites that experience severe winter weather conditions and which must be serviced in the summer months.
As of the end of the FY the NCSN has prepared 3 ANSS sites for installation pending checkout of the dataloggers. The NCSN has built all the battery boxes, cabling, communications equipment needed for all the ANSS sites to be deployed in the SF Bay Region (i.e., NCSN and NSMP sites). Permits are in process for the other 8 sites. The NCSN expects to install all of the ANSS sites before the end of the calendar year after completion of the conversion of 4 analog microwave telemetry nodes near/at Parkfield and Cape Mendocino to digital using satellite hardware and a remote Earthworm technology. The NSMP has received permits to install dataloggers at 9 urban sites but has not installed any dataloggers as of the end of the FY. All sites should be installed by the end of the calendar year.
The CISN transitioned from organizational activities in FY2001 to implementation activities in FY2002. The activities of the CISN are documented extensively at its website (http://www.cisn.org/). Notably, in April 2002 California Governor Gray Davis announced that the state would allocate $2.9 million for the integration and expansion of existing regional earthquake monitoring networks and production of data for online "ShakeMaps" and other rapid information to enhance the timeliness and efficiency of emergency response to devastating earthquakes. This funding was divided between Caltech, UC Berkeley, and the California Geological Survey. The CISN is using these funds to support ongoing operations in Southern California, upgrade strong motion and broadband instrumentation in northern California, integrate all monitoring operations into a highly robust monitoring network statewide, and implement an Engineering Data Center to rapidly distribute statewide strong-motion data.
The Advisory Committee met in Sacramento on 07/12/2002 to review CISN progress funded by the State and ANSS and to advise on future directions (see http://www.cisn.org/advisory/adv_report.2002.09.03.doc). The staff of the 5 member organizations of the CISN meet continually to develop standards, implementation plans, and software to meet the goal of an integrated statewide network. These activities are thoroughly documented at http://www.cisn.org/standards. As of the end of FY2002, the CISN has completed the installation of the physical T1 intranet ring connecting Pasadena, Menlo Park, Berkeley, Sacramento-CGS, and Rancho Cordova-OES and is configuring the network. Statewide integration of seismic networks, which is anticipated in FY2003, will enable the northern and southern California earthquake monitoring centers to have access to all seismic data in the state under normal operating situations and to have reasonable monitoring capability statewide (M>3) under abnormal situations.