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
the California Geological Survey (CGS), and the USGS combined
efforts to create a unified seismic system for southern California. With
major funding provided by the Federal Emergency
Management Agency (FEMA), the
California Governor's Office of Emergency Services
(OES), and the USGS, the TriNet project provided
the opportunity to upgrade and expand the monitoring infrastructure, 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 eighth year of collaboration and its seventh year
of funding from the OES.
organizational goals, products, management, and responsibilities of the CISN
organizations are described in the founding MOU and in the
strategic and implementation plans.
To facilitate activities among institutions,
the CISN has formed three management centers:
Southern California Earthquake Management
Center: Caltech/USGS Pasadena
Northern California Earthquake Management
UC Berkeley/USGS Menlo Park
Engineering Strong Motion Data Center:
California Geological Survey/USGS National Strong Motion Program
The Northern and Southern California Earthquake Management
Centers are operating as twin statewide earthquake processing centers serving
information on current earthquake activities, while
the Engineering Strong Motion Data Center has the responsibility for
producing engineering data products and distributing them to the
The Steering Committee, made up of two
representatives from each core institution and a representative from OES, oversees CISN projects.
The position of chair rotates among the institutions;
Rob Clayton took over as chair of the Steering Committee in June 2008 from Jeroen Tromp to complete Caltech's tenure.
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 October 2007. Agendas from the meetings
and the resulting reports may be accessed through the CISN Web site
The Steering Committee has formed 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 enhances 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.
The USGS Advanced National Seismic System (ANSS) is being developed 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).
Over the past 9 years, ANSS funding in California has been directed
primarily to the USGS Menlo Park to expand the strong-motion instrumentation
in the San Francisco Bay Area. As a result, more than 100
sites have been installed or upgraded, significantly improving the
data available for ShakeMaps.
As the ANSS moves forward, committees and working groups are being
established to address issues of interest. BSL faculty and staff have
been involved in several working groups of the Technical
including Doug Dreger, Pete Lombard, Doug Neuhauser, Bob
Uhrhammer, and Stephane Zuzlewski.
The California Governor's Office of Emergency Services has
had a long-term 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, OES 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 OES.
Funding for 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,
OES support led to the establishment of 3-year contracts to the UC Berkeley,
Caltech, and the California Geological Survey for CISN activities. The first
multi-year award covered activities in 2002-2005. The three-year contract for 2006-2008 has just been completed.
Past CISN-related activities are described in previous annual reports.
In late 2003, the CISN concluded a memorandum of agreement with
the Incorporated Research Institutions in Seismology (IRIS) covering
the duration of the USArray project in California. As a result, data from 19 stations
operated by the
BSL and 41 stations operated by Caltech were contributed to USArray's travelling array (TA) during its
The BSL also provided accelerometers for use at TA sites which might be
of interest as future BDSN stations. We monitored the data
from these stations in real time and included the data in ShakeMaps and
moment tensors. In addition, data from these TA stations
were included in our development of new parameters that are valid statewide for determining (see Research Study 34.). The TA moved out of California during the fall of 2007, and the BSL adopted eight of the sites. Instrumentation has been installed at RAMR, HAST, HATC, HELL, and SUTB (see Section 1). Support for the equipment has come from FEMA Hazard Grant Mitigation Program Funds and from CISN funding. Vaults have been left open at P01C, S04C, and V03C, which the BSL will instrument when funding becomes available.
Map showing the geographical distribution of the CISN partners
and centers. The communications ``ring" is shown schematically with
installed links (solid lines).
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.
As part of their effort within the CISN, the BSL and the USGS Menlo
Park are implementing the new generation of the Northern
California joint notification system. Section 8
describes the operations of the existing Management Center and
reports on the design and implementation progress.
In order to move ahead with plans for restructuring the Northern
California earthquake monitoring system, the USGS Menlo Park
and BSL have been improving their communications infrastructure.
At present, the BSL and the USGS Menlo Park are 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 3.8)
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
has reconfigured this frame-relay circuit to serve as a second data
acquisition link. BDSN data acquisition is now 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
microwave or satellite service.
Unfortunately, we have not yet been able to obtain funding for such an
additional communication link.
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.
BSL staff are involved in many elements of the statewide integration
effort. The Standards Committee, chaired by Doug Neuhauser, continues to
define and prioritize projects important to the development and implementation 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 3.7).
The Northern California Earthquake Management Center (NCEMC)
is using data from the Southern California stations to estimate magnitudes on a routine basis.
A subset of these stations are being used for the moment tensor inversions,
a computation that is sensitive to the background noise level.
Data Exchange: Pick exchange was initiated between the NCEMC and its Southern California counterpart in 2001-2002. The software CISN has developed to produce and exchange the reduced amplitude timeseries has also been completed.
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
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.
The Software Calibration & Standardization: CISN partners are working to standardize
the software used for automatic earthquake processing and earthquake review, as
well as to calibrate it. Currently,
the software implemented at the NCEMC and at the Southern California Earthquake Management
Center is very different. During the past year in the NCEMC, we have worked on preparing a version of the Southern California TriNet software for implementation as CISN software in
Magnitude: Calibrating magnitude estimates has proven to be
more difficult than originally anticipated. As described
in 2003-2004, evidence indicates that
there is a bias between the Northern and Southern California
estimates of local magnitude .
Efforts to understand this issue have been hampered by
the lack of a good
statewide dataset. Bob Uhrhammer has
selected data from
180 earthquakes distributed throughout the state
and comprising recordings from 976 horizontal components
from the AZ, BK, CI and NC networks (see Research Study 34.). In January 2007, we agreed
on a function suitable for statewide use.
Station-specific corrections for have now been defined for
most broadband/strong motion stations. We are working to develop station-specific corrections for strong motion only stations, and to tie the new system in with historical stations.
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 QDDS to provide the authoritative event
information for Northern and Southern California.
The dearth of stations in the near source region of the 2003 San Simeon
earthquake raised the issues of
how to measure the quality of a ShakeMap and how to quantify
the uncertainty. A subset of the Working Group
worked on this issue, based on the work of Hok and Wald (2003).
Lin et al (2006) presented progress toward quantifying
ShakeMap uncertainty, and ShakeMaps are now published with a grade.
A second goal of this effort was 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
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.
Leap second compatibility: Northern and Southern California databases handled leap seconds differently. A major software programming effort in the past year has been directed toward taking this into account. The data processing and analysis software now treats leap seconds consistently. All packages can be configured to pass the time information to the database in nominal or true time, as necessary.
Standardization: The CISN's focus on standardization of
software continues. For example, the BSL and the
USGS Menlo Park are adapting the software
running at the SCEMC for use at the NCEMC and are currently
testing its various elements.
The adoption of Jiggle in northern California in late November 2007 was
the first step in the implementation of the new software. Current efforts
are directed toward the implementation and testing of the complete system (see Section 8). This software will be offered to other regional neworks of the ANSS in the near future.
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
infrastructure, and emergency
responders are invited to register for an account at
The application provides users with maps of
real-time seismicity and automatically provides access to Web-related
products such as ShakeMaps. CISN Display also
offers an open source GIS mapping
that allows users to plot freely available layers of public highways,
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.
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.
the CISN Web site (www.cisn.org)
has been supported by two servers located
at Berkeley and Caltech. The Web servers are set up so that the
load can be distributed between them, providing improved access
during times of high demand.
With the increased robustness provided by the new servers,
the CISN provides 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.
The CISN continues to support the dedicated Web site for
emergency managers. Following a suggestion from the Advisory
Committee, we have designed a Web site to provide personalized
access to earthquake information. Known as ``myCISN," the Web site
is available at eoc.cisn.org. Access to the Web
site is limited
to registered users in order to provide highly reliable access.
At present, ``myCISN" is a single Web server located at UC Berkeley.
However, modifications to the database are underway to allow for
multiple servers in the future. A second computer, already purchased,
will either be installed in Sacramento or
in Southern California.
As part of the CISN, the BSL is contributing to efforts to raise
awareness of earthquakes and preparedness as
the 140 anniversary of the 1868 Hayward Fault earthquake approaches
on October 21, 2008. In particular, we will be co-hosting
the Third Conference on Earthquake Hazards in the Eastern Bay Area
as well as organizing and participating in other related activities.
CISN activities at the BSL are supported by funding from the
Governor's Office of Emergency Services.
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
Committee, which includes Peggy Hellweg, Pete Lombard,
and Stephane Zuzulevski
Because of the breadth of the CISN project, many BSL staff members have been involved,
Peggy Hellweg contributed to this section. Additional information about the
CISN is available through reports from the Program Management Group.
Hok, S., and D. J. Wald,
Spatial Variability of Peak Strong Ground Motions: Implications for
ShakeMap Interpolations, EOS. Trans. AGU, 84(46), F1121, 2003.
Lin, K-W., D. Wald, B. Worden and A.F. Shakal,
Progress toward quantifying CISN ShakeMap uncertainty,
Eighth National Conference on Earthquake Engineering,
San Francisco, California, April 18-21, 2006.