WARNING--PROVISIONAL DATA, SUBJECT TO REVISION
The data displayed on these recent earthquakes pages are preliminary.
They are largely computer generated and may not have received
human review or official approval. Inaccuracies in the data
may be present because of instrument or computer malfunctions.
Subsequent review may result in significant revisions to the
data. Data users are cautioned to consider carefully the provisional
nature of the information before using it for decisions that
concern personal or public safety or the conduct of business
that involves substantial monetary or operational consequences.
People - Northern California Seismic
Net - USGS
The web pages you are viewing are the end result of the
efforts of many individuals. At the USGS in Menlo Park, California,
the process begins with the installation and operation of
seismometers and associated telecommunications equipment throughout
the state. The following individuals designed, installed and
continue to maintain these instruments: Jerry Eaton, John
VanSchaack, Wes Hall, Grey Jensen, Dave Reneau, Dave Croker,
John Kempe, John McClearn, Gonzalo Mendoza, Tom Burdette,
Don Farrell, Sam Rodriguez, Daisy Hom, Don Ritchey, Fred Fischer,
Bob Somera, and Lester Sutherland.
The computer systems that detect the occurrence of earthquakes,
locate their hypocenters, estimate their magnitude, and compute
their focal mechanisms were developed by Rex Allen, Jim Ellis,
Alex Bittenbinder, Barbara Bogaert, Lynn Dietz, Will Kohler,
Carl Johnson, Bill Ellsworth, David Oppenheimer, Paul Reasenberg,
Al Lindh, and Fred Klein. The alarm software that notifies
the seismologists by pager, creates the maps, archives the
earthquake data, and issues e-mail about earthquakes was written
by Bruce Julian and Andy Michael. The computers are maintained
by Greg Allen.
The seismologists who are on-call 24 hours/day to review
the data from significant events are Rick Lester, Fred Klein,
Steve Walter, Jim Luetgert, and David Oppenheimer.
People - Northern California Seismic
Net - UC Berkeley
At the Berkeley Seismological Laboratory, many people contribute
to the earthquake monitoring program. Rich Clymer, John Friday,
Marvin Hilger, Bill Karavas, David Rapkin, and Russel Sell
have been responsible for the design, installation, and maintenance
of the Berkeley Digital Seismic Network. The software that
handles the data acquisition and processes earthquakes for
the determination of location, magnitude, and seismic moment
tensors was developed by Doug Dreger, Joe Durek, Steve Fulton,
Lind Gee, Tom McEvilly, Doug Neuhauser, Mike Pasyanos, Barbara
Romanowicz, and Bob Uhrhammer.
Additional data analysis and data archiving are performed
by Rick McKenzie and Doug Neuhauser. The computer systems
are maintained by Doug Neuhauser and Charley Paffenbarger.
Maintenance of web pages is performed by Lind Gee and Doug
Seismologists who are on-call 24 hours/day to review data
and ensure the smooth operation of the earthquake monitoring
system are Mike Antolik, Ludovic Breger, Joe Durek, Steve
Fulton, Lind Gee, Peg Johnson, John Lynch, Charles Megnin,
Doug Neuhauser, Charley Paffenbarger, and Paul Parker.
People - Southern California Seismic
Network - USGS & Caltech
(A cooperative project of the U.S.Geological Survey & the
Seismological Laboratory at Caltech).
At the SCSN in Pasadena, California the detection and processing
of earthquake data presented in these Web pages involves the
following individuals. Wayne Miller, Dave Johnson, Chuck Koesterer,
Gary Cone, Bob Taylor, Bob Cone, Scott Lydeen, Alberto Devora,
Mike Watkins, Carl McCaughey, and Bill Curtis are responsible
for the design, installation, and maintenance of seismometers
in Southern California. The software that detects the occurrence
of earthquakes,and determines preliminary hypocenters and
estimates of magnitude was developed by Bob Dollar, Doug Given,
Allan Walter, Phil Maechling, Hiroo Kanamori, Sam Stewart,
Peter Johnson, Carl Johnson, and Jim Mori. The alarm software
that notifies the seismologists by pager, and issues e-mail
about earthquakes was written by Doug Given, Steve Bryant,
and Phil Maechling. The computers are maintained by Stan Schwarz,
Katrin Hafner, and Phil Maechling and Bob Dollar.
Operation of data processing systems and further data analyses
are done by Kate Hutton, Bob Dollar, Nick Scheckel, Karen
Kahler, Joe Franck, Paul Roberts, and Mandy Johnson. Maintenance
of web pages and data archiving are done by Lisa Wald, Katrin
Hafner, John Marquis, and Karen Kahler.
The seismologists who rotate call duty are on-call 24 hours/day
to review the data from significant events. They are Egill
Hauksson, Kate Hutton, Lucy Jones, Bob Dollar, Doug Given,
and Nick Scheckel.
California highways were extracted and compiled by volunteer
Kirstin Mortensen and Carl Mortensen. Nevada placenames were
supplied by Ken Smith and David Vonseggern at UNR, Nevada
roads by Robert Miller at USGS.
Faults for the index map were provided by Art Frankel and
Jim Lienkaemper. Faults on the zoomed-in maps came from C.W.
Jennings, 1992, California Division of Mines and Geology Open-File
Report 92-03. (This map has been superseded by Jennings, C.W.,
1994, Fault activity map of California and adjacent areas,
with locations and ages of recent volcanic eruptions: California
Division of Mines and Geology, Geologic Data Map No. 6, map
Andy Michael wrote the programs to prepare the earthquake
data. Doug Neuhauser and Steve Malone assisted with advice
and examples in the construction of the catalog merging software.
Bob Simpson - with lots of help and suggestions from Bill
Ellsworth, Dave Oppenheimer, and Andy Michael - designed the
base maps, links, and programs that update the web pages.
Jim Luetgert designed and programmed the waveforms pages for
northern California. In addition Carl Mortensen, Steve Malone,
Lind Gee, Lucy Jones, Stan Silverman, Paul Reasenberg, sharp-eyed
Lynn Dietz and many others offered valuable ideas and suggestions.
The appearance of these pages was greatly improved with
help and suggestions from Sara Boore. (She bears no responsibility
for the remaining defects!) Paul Reasenberg helped select
colors that would be distinguishable by color-blind viewers.
Barbara Simpson offered advice on colors, and suggested ways
to make the earthquake lists more readable.
Maps are updated using the subroutine library gd
written by Thomas Boutell,
and the gd interpreter tgd
written by Bradley
K. Sherman. Program XV
by John Bradley and xpaint by David Koblas were used extensively
in the preparation of the basemaps. Many thanks to these gentlemen
for their nifty programs!
The earthquake location data, seismologist comments, and
additional information (e.g., seismogram images and mechanisms)
are distributed among various operators of the recenteqs software
using a program called QDDS written by Stephen Jacob and Alan Jones.
A single, authoritative catalog of earthquake locations
is generated from all of the various conflicting reports about
an earthquake contributed by different seismic networks using
a program called CNSSmerge written by Andy Michael and re-written in Java
by Alan Jones.