Subsections


California Integrated Seismic Network



Introduction

Advances in technology have made it possible to integrate separate earthquake monitoring networks into a single seismic system as well as to unify earthquake monitoring instrumentation. In California, this effort began in the south with the TriNet Project. There, Caltech, the California Geological Survey (CGS), and the USGS created a unified seismic system for Southern California. With major funding provided by the Federal Emergency Management Agency (FEMA), the California Governor's Emergency Management Agency (CalEMA), and the USGS, monitoring infrastructure was upgraded and expanded, combining resources in a federal, state and university partnership. In 2000, the integration effort expanded to the entire state with the formation of the California Integrated Seismic Network (CISN, see 2000-2001 Annual Report). To this end, UC Berkeley and the USGS Menlo Park and Pasadena offices joined forces with Caltech and the CGS. The CISN is now in the tenth year of collaboration and its ninth year of funding from CalEMA.

CISN Background

Organization

The organizational goals, products, management, and responsibilities of the CISN member organizations are described in the founding memorandum of understanding and in the strategic and implementation plans. To facilitate activities among institutions, the CISN has three management centers:

The Northern and Southern California Earthquake Management Centers operate as twin statewide earthquake processing centers, serving information on current earthquake activities, while the Engineering Strong Motion Data Center is responsible for producing engineering data products and distributing them to the engineering community.

The Steering Committee, made up of two representatives from each core institution and a representative from CalEMA, oversees CISN projects. The position of chair rotates among the institutions; Barbara Romanowicz took over as chair of the Steering Committee in December 2009 from Rob Clayton.

An external Advisory Committee represents the interests of structural engineers, seismologists, emergency managers, industry, government, and utilities, and provides review and oversight. The Advisory Committee is chaired by Stu Nishenko of Pacific Gas and Electric Company. It last met in January 2009. Agendas from the meetings and the resulting reports may be accessed through the CISN Web site (http://www.cisn.org/advisory).

The Steering Committee has commissioned other committees, including a Program Management Group to address planning and coordination and a Standards Committee to resolve technical design and implementation issues.

In addition to the core members, other organizations contribute data that enhance the capabilities of the CISN. Contributing members include: University of California, Santa Barbara; University of California, San Diego; University of Nevada, Reno; University of Washington; California Department of Water Resources; Lawrence Livermore National Lab; and Pacific Gas and Electric.

CISN and ANSS

The USGS Advanced National Seismic System (ANSS) is developing along a regionalized model. Eight regions have been organized, with the CISN representing California. David Oppenheimer of the USGS represents the CISN on the ANSS National Implementation Committee (NIC).

This year, the CISN is benefiting from the America Recovery and Reinvestment Act (ARRA). The ANSS has received funds from the ARRA to improve seismic monitoring throughout the nation and the world. In California, these funds are being directed toward replacing old data loggers in both Northern and Southern California, as well as improving installations at individual stations and adding strong motion sites in the form of NetQuakes sensors. The BSL's ARRA-funded activities are described in Operational Sections 1, 4 and 3.

As the ANSS moves forward, committees and working groups are established to address issues of interest. BSL faculty and staff have been involved in several working groups of the Technical Integration Committee, including Doug Dreger, Peggy Hellweg, Pete Lombard, Doug Neuhauser, Bob Uhrhammer, and Stephane Zuzlewski. Last Fall, the BSL hosted two ANSS workshops. In October 2009, operators of ANSS Regional Seismic Networks met in the Hearst Mining Building at UC Berkeley for NetOps IV, a workshop to learn about the new version of the ShakeMap program. The next month, November 2009, the BSL hosted a one-day ANSS workshop on the future of the ANSS catalog (http://www.ncedc.org/anss/catalog-search.html), followed by a meeting of the ANSS National Implementation Committee (NIC).

CISN and CalEMA

CalEMA has long had an interest in coordinated earthquake monitoring. The historical separation between Northern and Southern California and between strong-motion and weak-motion networks resulted in a complicated situation for earthquake response. Thus, CalEMA has been an advocate of increased coordination and collaboration in California earthquake monitoring and encouraged the development of the CISN. In FY01-02, Governor Gray Davis requested support for the CISN, to be administered through CalEMA. Funding for the California Geological Survey, Caltech and UC Berkeley was made available in spring 2002, officially launching the statewide coordination efforts. Following the first year of funding, CalEMA support led to the establishment of 3-year contracts to UC Berkeley, Caltech, and the California Geological Survey for CISN activities. We have just completed the second year of the third three-year contract (2008-2011). Past CISN-related activities are described in previous annual reports.

2009-2010 Activities

We have just completed the first full year of operation in the NCEMC (Northern California Earthquake Management Center) with the new suite of earthquake monitoring software. In the past, we have called this system the CISN software. In 2008, it was adopted by the ANSS as the system to be used by the regional networks for their operations and earthquake reporting, and it is now called the ANSS Quake Monitoring System, or AQMS. The NCEMC made the switch to the AQMS software package in June 2009, and the software is now operating at the BSL and in Menlo Park. CISN funding from CalEMA contributed to this transition, and has supported a number of other activities at the BSL during the past year as well.

Figure 3.9: Map showing the geographical distribution of the CISN partners and centers. The communications ``ring'' is shown schematically with installed links (solid lines).
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Figure 3.10: Map showing the 30 stations selected to send data directly to the Northern and Southern California processing centers, and the 5 stations that send data directly to the Engineering Data Center and the Southern California processing center.
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Northern California Earthquake Management Center

As part of their effort within the CISN, the BSL and the USGS Menlo Park have completed implementation of the next generation Northern California joint earthquake information system, the AQMS software. Operational Section 8 describes the operation of this system and reports on implementation progress.

For monitoring earthquakes in Northern California, the USGS Menlo Park and BSL have improved their communications infrastructure. The BSL and the USGS Menlo Park are currently connected by two dedicated T1 circuits. One circuit is a component of the CISN ring, while the second circuit was installed in 2004-2005 (Figure 3.11) to support dedicated traffic between Berkeley and Menlo Park above and beyond that associated with the CISN.

The installation of the second dedicated T1 between Berkeley and Menlo Park freed up a frame-relay connection deployed by the BSL as part of the CalREN project in mid-1990s. The BSL now uses this frame-relay circuit as a second data acquisition link. BDSN data acquisition is distributed between two frame-relay T1 circuits, eliminating what had been a single point of failure. An additional Permanent Virtual Circuit (PVC) has also been implemented at each BDSN site so that each station has connections to both T1s. This has improved the robustness of data acquisition at the BSL by providing redundancy in the incoming circuit.

In the long term, the BSL and USGS Menlo Park hope to be connected by high-bandwidth microwave or satellite service. Unfortunately, we have not yet been able to obtain funding for such an additional communication link.

Figure 3.11: Schematic diagram illustrating the connectivity between the real-time processing systems at the USGS Menlo Park and UC Berkeley, forming the Northern California Management Center, and with other elements of the CISN.
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Statewide Integration

Despite the fact that AQMS software is now operating in both Northern and Southern California, efforts toward statewide integration continue. BSL staff are involved in many elements of these efforts. The Standards Committee, chaired by Doug Neuhauser, continues to define and prioritize projects important to the ongoing development and operation of the statewide earthquake processing system and to establish working groups to address them (see minutes from meetings and conference calls at http://www.cisn.org/standards/meetings.html).

Dual Station Feeds: Early in the existence of CISN, ``dual station feeds'' were established for 30 stations (15 in Northern California and 15 in Southern California) (Figure 3.10). Because of decreases in funding and other issues, Northern California now sends data from 13 stations to Southern California in real time, and Southern California sends data from 12 to Northern California. The Northern California Earthquake Management Center (NCEMC) is using data from the Southern California stations to estimate magnitudes on a routine basis. In addition, some of the stations are used in moment tensor inversions, a computation that is sensitive to the background noise level.

Data Exchange: Part of the AQMS software allows reduced amplitude timeseries to be produced and exchanged. Currently, these timeseries are being exchanged at the NCEMC, but not yet statewide. Using a common format, the CISN partners continue to exchange observations of peak ground motion with one another following an event or a trigger. This step increases the robustness of generating products such as ShakeMap, since all CISN partners now exchange data directly with one another. This also improves the quality of ShakeMaps for events on the boundary between Northern and Southern California, such as the San Simeon earthquake, by allowing all data to be combined in a single map. Finally, this is a necessary step toward the goal of generating statewide ShakeMaps.

In the past year, we have also implemented the exchange of waveforms for event gathers. Since then, we have been working to implement statewide exchange of reduced amplitude data, including PGA, PGV, PGD and ML100 for use in real-time processing.

The Software Calibration & Standardization: CISN partners have calibrated and standardized much of the software used for automatic earthquake processing and earthquake review, now the AQMS software. The AQMS software now serves as the real-time system operating in the NCEMC. The transition was made in June 2009.

Local Magnitudes: Since the transition to the AQMS software in Northern California in June 2009, local magnitudes are calculated throughout the state using the new $logA_{o}$ function and the associated station-specific corrections for broadband/strong motion stations, and also for strong-motion only stations. We are now focusing magnitude development in two directions. First, we are investigating the discrepancy Southern California has discovered between $M_{L}$ and $M_{w}$ for events with magnitudes greater than $M_{L}$ 4. Second, we are working to tie the new local magnitude system to vertical components, whether short period or broadband. A final component of the magnitude efforts is the determination of a magnitude reporting hierarchy. For the near future, each region will continue to use its own preferences for magnitude reporting.

ShakeMap: At present, ShakeMaps are generated on 5 systems within the CISN. Two systems in Pasadena generate ``SoCal'' Shakemaps; 2 systems in the Bay area generate ``NoCal'' Shakemaps; and 1 system in Sacramento generates ShakeMaps for all of California. The Sacramento system uses EIDS ( Earthquake Information Distribution System) to provide the authoritative event information for Northern and Southern California.

For the past year, we have been evaluating the new release of the program, ShakeMap 3.5, before using it to publish ShakeMaps for new events and before recalculating the ShakeMaps for all events in the catalog. As part of the process to prepare for the recalculation, we have reviewed the magnitudes of many events with $M$ 3.5 or greater in the aftershock sequence of the 2003 San Simeon earthquake.

A second goal is to improve the robustness of ShakeMap generation and delivery by taking advantage of the fact that ShakeMaps are generated in the Bay Area, Pasadena, and Sacramento. Ongoing efforts in this direction will likely be based on the new USGS ShakeMap webpages at the National Earthquake Information Center.

Location Codes: The CISN adopted a standard for the use of ``location'' codes (part of the Standard for the Exchange of Earthquake Data [SEED] nomenclature to describe a timeseries based on network-station-channel-location) in the late fall of 2003. USGS and UC Berkeley developers modified the Earthworm software to support their use. After the transition at USGS Menlo Park away from the CUSP analysis system to Jiggle in late November 2006, all networks in the CISN implemented location codes in their systems. During the past year, as we deploy new data loggers using ARRA funding, we have begun the transition to non-blank location codes for the BDSN stations. When the data logger at a station is replaced with an ARRA-funded data logger, it receives the location code ``00.'' Borehole seismic stations will have the location code ``40.''

Metadata Exchange: Correct metadata are vital to CISN activities, as they are necessary to ensure valid interpretation of data. CISN is working on issues related to their reliable and timely exchange. The CISN Metadata Working Group compiled a list of metadata necessary for data processing and developed a model for their exchange. In this model, each CISN member is responsible for the metadata for its stations and for other stations that enter into CISN processing through it. For example, Menlo Park is responsible for the NSMP, Tremor, and PG&E stations, while Caltech is responsible for the Anza data. At the present time, dataless SEED volumes are used to exchange metadata between the NCEMC and the SCEMC. The Metadata Working Group is developing a Station XML format for metadata exchange. This vehicle is expandable, and will probably allow exchange of a more comprehensive set of metadata than dataless SEED volumes, some of which may be necessary for other systems, for example in V0 formatted data.

Standardization: The CISN's focus on standardization of software continues. The complete system is now implemented and providing real-time earthquake information in the NCEMC (see Operational Section 8). The software is currently being implemented at other regional networks of the ANSS.

CISN Display

CISN Display is an integrated Web-enabled earthquake notification system designed to provide earthquake information for emergency response at 24/7 operations centers. First responders, organizations with critical lifelines and infrastructure, and emergency responders are invited to register for an account at http://www.cisn.org/software/cisndisplay.htm.

The application provides users with maps of real-time seismicity and automatically provides access to Web-related earthquake products such as ShakeMaps. CISN Display also offers an open source GIS mapping tool that allows users to plot freely available layers of public highways, roads and bridges, as well as private layers of organizational-specific infrastructure and facilities information. The current version of CISN Display is 1.4. Its primary enhancement over the previous version is the development of a kiosk mode for public display purposes.

Earthquake Information Distribution

The USGS hosted a workshop in October 2004 to develop plans for the installation and use of the EIDS software. Doug Neuhauser and Pete Lombard participated in this workshop, which resulted in a document outlining the steps necessary for the installation and migration of the earthquake notification system from the current Quake Data Distribution Services (QDDS) to EIDS. During the past year, the NCEMC transitioned to using the EIDS system for publishing earthquake information.

Outreach

Starting in FY05-06, the CISN Web site (www.cisn.org) was been supported by two servers located at Berkeley and Caltech. The Web servers were set up so that the load could be distributed between them, providing improved access during times of high demand. With these servers, the CISN provided access to certain earthquake products directly from www.cisn.org. For example, ShakeMaps are now served directly from the CISN Web site, in addition to being available from several USGS Web servers and the CGS. The design and content of http://www.cisn.org continues to evolve. The Web site is an important tool for CISN outreach as well as for communication and documentation among the CISN partners. Unfortunately, the Caltech server died during the past year, and only the Berkeley server is online providing information to the public and emergency responders.

The CISN supports a dedicated Web site for emergency managers. This Web site provides personalized access to earthquake information. Known as ``myCISN,'' the Web site is available at eoc.cisn.org. To provide highly reliable access, the Web site is limited to registered users.

As part of the CISN, the BSL contributed to efforts in 2009-2010 to raise awareness of earthquakes and earthquake preparedness. The BSL is a member of the Earthquake Country Alliance, a state-wide organization of people, institutions and agencies associated with earthquake response and research. In the past year, we publicized the state-wide ShakeOut on October 15, 2009 and participated in it. We are now working toward a statewide California ShakeOut on October 21, 2010 at 10:21 (see http://www.shakeout.org for more information and to sign up).

Acknowledgements

CISN activities at the BSL are supported by funding from the California Emergency Management Agency, CalEMA.

Barbara Romanowicz and Peggy Hellweg are members of the CISN Steering Committee. Peggy Hellweg is a member of the CISN Program Management Group, and she leads the CISN project at the BSL with support from Doug Neuhauser. Doug Neuhauser is chair of the CISN Standards Committee, which includes Peggy Hellweg, Pete Lombard, Taka'aki Taira, and Stephane Zuzulewski as members.

Because of the breadth of the CISN project, many BSL staff members have been involved, including: John Friday, Jarrett Gardner, Peggy Hellweg, Bill Karavas, Oleg Khainovski, Rick Lellinger, Pete Lombard, Doug Neuhauser, Charley Paffenbarger, Taka'aki Taira, Stephen Thompson, Bob Uhrhammer, and Stephane Zuzlewski. Peggy Hellweg contributed to this section. Additional information about the CISN is available through reports from the Program Management Group.

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