Other Projects and Activities
August 30, 1996
3D Dynamic Rupture Problem and it's Implementation into Finite Difference Code, speaker: Raul Madariaga, Ecole Normale Superieure, Paris
November 18, 1996
ORBIT: NASA Astronauts Photograph the Earth, speaker Jay Apt, NASA
November 20, 1996
Role of Cross-Faults as Tears in Thrust Ramps in the Ventura and Santa Barbara Fold Belts, speakers: Larry Gurrola and Marc Kamerling, Institute for Crustal Studies
December 3, 1996
Pre-seismic Tilt and Triggered Reverse Faulting due to unloading in a Diatomite Quarry near Lompoc, California, speaker: Arthur Sylvester, Department of Geological Sciences and Institute for Crustal Studies
February 21, 1997
Faulting: Is Truth Stranger than Friction?, speaker: Richard Sibson, University of Otago
March 4, 1997
Physical and Numerical Modeling of Ground Motion from Thrust Faults and Normal Faults, speaker: Jim Brune, University of Nevada, Reno
March 14, 1997
The "Big Bend" of the San Andreas Fault: Hypothesis of Tectonic Extrusion, speaker: Ed Keller, Department of Geological Sciences and Institute for Crustal Studies
April 4, 1997
Contemporary Aseismic Uplift in the Transverse Ranges, speaker: Arthur Sylvester, Department of Geological Sciences and Institute for Crustal Studies
April 11, 1997
Three Dimensional Seismo-Tectonic Imaging of the Eastern Transverse Ranges: the Santa Monica Seismic Zone (SMSZ) and Evidence for Critical Wedge Tectonics, speaker: Pete Geiser, CogniSeis Development
May 9, 1997
Exploring the Crest of the Southern East Pacific Rise Using Deep-Towed Cameras and Sonars: Results of the Fall '96 Sojourn Expedition, speaker: Rachel Haymon, Department of Geological Sciences
May 21, 1997
New Perspectives on Peak Velocity Ground Motions from Earthquakes using Broad-Band Instruments, speaker: Dan O'Connell, US Bureau of Reclamation
June 13, 1997
Cretaceous and Tertiary tectonics of Western Marie Byrd Land, West Antarctica, speaker: Bruce Luyendyk, Department of Geological Sciences and Institute for Crustal Studies
Borehole Initiative Workshop, Host: Southern California Earthquake Center, University of Southern California; Los Angeles, California
SCEC Phase III Report, Hosts: Jamison Steidl, Institute for Crustal Studies; Santa Barbara, California
Campus-Laboratory Collaborative Workshop, Host: Lawrence Livermore National Laboratory; Ramona, California
3rd Annual BVDA-GVDA (Borrego Valley and Garner Valley Downhole Arrays) Data Utilization Meeting, Host: Jamison Steidl, Institute for Crustal Studies; Honolulu, Hawaii
The SCEC organization continues to award Summer internships to our undergraduate students. In the Summer of 1996 we had three: Erik Bartsch, Marcy Davis, and Gretchen Mullendore.
Erik studied the geology of the region immediately offshore UCSB. He was looking for expression of the North Channel fault on the sea floor there. He mapped the outcrop pattern of the Monterey and Sisquoc formations and found that it indicated where the fault was below the sea floor.
Marcy studied exposed marine terraces along the Santa Barbara Mesa. Her goal was to determine the uplift rate and whether the uplift is a result of block faulting or a combination of faulting and folding. She found that the Mesa rises at a rate of 0.6 meters per thousand years due to block faulting along the Mesa fault.
Gretchen examined a unique set of ground motion acceleration time histories from the 1994 Northridge earthquake. She analyzed the seismic data collected by the Los Angeles Department of Water and Power (LADWP) at their Van Norman Dam complex. All accelerometers were within an area 3 km in length by 1.5 km in width. In spite of the short distance between accelerometers there was significant variation in the maximum acceleration (factors of 2) between different stations. Part of the explanation was in the different soil response among the stations. There were also strong indications of nonlinear soil response at some stations.
Art Sylvester has involved many students in precise geological surveying. This year his students have resurveyed leveling lines in the Los Angeles and Ventura basins. Another group of students began work with recently acquired GPS equipment to measure the vertical movement of the Transverse Ranges in Southern California.
Hydrocarbon Seeps Project
Erik Bartsch worked as an assistant on Luyendyk's Santa Barbara Channel hydrocarbon seeps project. He made an independent study of the controls of offshore geological structure on the location of the seeps. He made a poster presentation on his work at the December, 1996 American Geophysical Union meeting in San Francisco.
Marine Geology Offshore Marie Byrd Land Antarctica
Several undergraduates worked on Luyendyk's project to map the geological structure of the continental shelf off Marie Byrd Land, Antarctica. Carmen Alex worked with Dr. Doug Wilson on marine gravity data mapping and interpretation. Marcy Davis worked with Geoff Ely on seismic data processing. Nathan Warmerdam produced a GIS for Marie Byrd Land with Kirsten Zellmer that incorporated archival and original data from Luyendyk's expedition.
Campus Laboratory Collaboration Project
Carmen Alex, Elizabeth Cochran and Todd Tyler helped shoot five 24 channel seismic lines at selected sites on the UCSB campus near Engineering I and Webb Hall.
Data for these refraction profiles was collected with a portable Strataview field instrument.
They ran preliminary velocity profiles on the Strataview which will be used for in-depth analysis of the mechanical properties of campus bedrock and overburden.
This information will be used for the project objective to determine the campus ground motion sensitivity from local and distant earthquakes.
Brownfields Project, Goleta-Santa Barbara
Steve Cullen and Lorne Everett collaborated with Santa Barbara County and consulting firms to submit a successful proposal to the EPA Brownfields Program. This program is aimed at funding the environmental characterization of land areas contaminated by hazardous waste releases in order to provide a basis for contaminated site remediation leading to the reclaiming of useful land.
Earthquake Outreach Activities
The 1996-97 year has been a successful year in disseminating our research on the earthquake hazards of Santa Barbara to students as well as local citizens. Our audiences have ranged from city geologists and county planning staff to the general public. Our objective is to disseminate research results to the scientific and consulting community as well as educate the general public on the focus of our research and state of knowledge on earthquakes in general and locally.
ICS earthquake hazard exhibits have been well-received in all forums. We have led well-attended field trips on the "Earthquake Hazards of the Santa Barbara Fold Belt" for undergraduates from the University of Arizona and new graduate students from UC Santa Barbara. We are currently revising our field trip guidebook to include additional field stops and expect to lead a two-day field trip in the Santa Barbara area during the Spring, 1998 GSA meeting.
Researcher Kim Olsen was interviewed by journalists from a TV station in Vienna, Austria, who were on a 3-week filming-and-interviewing tour in the US. The Discovery Channel used a 3-D simulation model from research done by Kim Olsen and Ralph Archuleta on a program about earthquakes. Ralph Archuleta was interviewed by KEYT news about local earthquakes and was also interviewed by the Santa Barbara News Press for his work on Earthquake Hazards in the Santa Barbara area. KEYT also interviewed Craig Nicholson about Tsunamis.
Professor Edward Keller and graduate student Larry Gurrola gave a presentation on local earthquakes to UCSB parents attending Parent's Day on campus in November. Larry Gurrola also participated in Kinko's "Earthquake Preparedness Day" at Kinko's corporate headquarters in Ventura.
Dr. Kim Olsen participated in "Microcomputers and Instructional Media Day" here at UCSB in the UCEN, demonstrating his computer simulations of earthquakes.
Researcher Craig Nicholson gave a talk to the International Boys and Girls Club and the Goleta Valley Optimist Club on earthquakes, earthquake hazard, and earthquake mitigation.
Ralph Archuleta was invited to give talks for a South Coast Geological Society meeting and the Ventura chapter of the Sigma Xi Engineering Society.
ICS students Larry Gurrola, Aaron Martin, Elizabeth Cochran, Kirsten Zellmer, Fabian Bonilla, and David Valentine participated in Santa Barbara's Earth Day '97 by setting up seismic equipment in De La Guerra Plaza downtown Santa Barbara and giving presentations and demonstrations throughout the day.
Public School Presentations:
ICS researchers and students made numerous presentations at public schools on earthquake issues. Aaron Martin and David Oglesby gave a talk on earthquakes at Santa Barbara Christian School to Ms. Krista Beard's 5th and 6th grade class. Aaron Martin and Jamison Steidl gave an earthquake presentation to an Isla Vista elementary school 5th Grade class who visited the Institute for Crustal Studies. Geoff Ely did a presentation on plate tectonics and seismicity for Peggy Lubchenco's La Colina Jr. High class. Following that, Aaron gave a brief presentation on modern data acquisition systems and recorded "stomps" for each of the students.
ICS also donated surplus Mac SE computers to Peabody Elementary School.
Jamie Steidl gave a presentation to the Community Awareness and Emergency Response organization for Ventura and Santa Barbara Counties. Both Jamie Steidl and Kim Olsen are part of a Los Angeles City Task Force Steering Committee providing estimates of ground motion from future damaging earthquakes which can be used by engineers in the retrofit design of vulnerable structures in the Los Angeles area.
Ralph Archuleta supplied the City of Los Angeles with earthquake simulation data to help develop a scenario for the city's annual earthquake exercise.
Ralph Archuleta organized a short course "Seismic Evaluation Using Site Specific Ground Motion" for the Federal Energy Regulatory Commission February 3-7, 1997. This course was attended by 30 professionals from six regional offices and their main headquarters in Washington DC. The material, centered on seismic evaluation of dams, was presented by Archuleta, Kim Olsen, Jamison Steidl, Alexei Tumarkin, David Oglesby, Fabian Bonilla, all of ICS, and Norm Abrahamson, a consulting engineering seismologist from Piedmont, Ca.
Archuleta also gave an invited talk to the Interagency Committee on Dam Safety Technical Seminar, Feb. 19-20, Emmitsburg, Maryland: Development of Ground Motion Parameters for Dam Safety Evaluation. The title of the talk was Deterministic Sources and Theoretical Ground Motions.
ICS World Wide Web earthquake pages
The Institute for Crustal Studies (ICS) home page contains general information of public interest concerning California earthquakes. Highlights include:
Seismic Datasets and Technical Reports for the Alexandria Digital Library
David Valentine and Bruce Luyendyk of ICS and Terry Smith of the Alexandria project are collaborating on developing a set of information for incorporation into the Alexandria Digital Library (ADL), a distributed digital library for geographically-referenced information.
The ADL provides access over the World Wide Web to a subset of the UCSB Map and Imagery Libraries holdings, as well as other geographic datasets. When the Alexandria Digital Library (ADL) becomes available to University of California users in October of 1997, items of interest to the ICS community will be 15,000 references from the AGI GEOREF bibliography, a catalog of local digital datasets, scanned text documents, and information from the Southern California Earthquake Center.
Users will be able to select a region of interest and be able to browse through the results from their desktops. Some of the catalog files include: Southern California Earthquake Data Center (Earthquake Catalogs, GPS observations, GIS data, Weekly reports), 20,000 miles of single fold seismic reflection lines (GTS data set, including 600+ files for Santa Barbara and Ventura on-line), 50 Seismic Hazard Documents, and the Ventura Basin Geologic Study (Hopps data set).
David Valentine has been working with ADL on cataloging the information.
Collaboration with the U.S. Navy
Dr. Lorne Everett, Director of the ICS Vadose Zone Laboratory, played a big role in initiating an agreement to share personnel and facilities with the U.S. Naval facility at Port Hueneme. Dean David Chapman of Letters and Science was part of the negotiations that lead to this research pact that will bring over $500,000 of scientific equipment to the University. The equipment will be used by ICS, Geology, Geography and the School of Environmental Science and Management. The Navy has already delivered to the Vadose Lab a $250,000 mass spectrometer. This and other equipment gifted to the University will be used for collaborative research on environmental issues.
Seismic Hazards Consulting and Seismic Instruments
Three-Dimensional modeling of the seismic response of the Kanto Basin, Japan:
During the last week of July 1996 Bob Nigbor and Kim Olsen visited Kajima Corporation in Tokyo where Olsen implemented his 3-D finite-difference modeling code as well as trained the researchers in the use of it. The trip was sponsored by Agbabian Associates. They successfully simulated 3-D wave propagation in the Kanto Basin for a M 6.5 earthquake during their stay, and the code was later used by Kajima researchers to simulate the 1923 Kanto earthquake.
Three-Dimensional modeling of the seismic response of the Borrego Valley:
Agbabian Associates have assembled a 3D model of the Borrego Valley in Southern California. Kim Olsen and they used this model to simulate 2 Hz wave propagation for a M 4.8 aftershock of the 1992 Landers earthquake. The earthquake was recorded by a surface array of digital three-component instruments as well as a downhole array in the center of the valley. These data were compared to the results of 1-D, 2-D and 3-D simulations where they used the deepest borehole (rock) recording as an oblique-incident plane wave source. The main results include that the 3-D and 2-D but not 1-D simulations provide satisfactory fit to data, including anelastic attenuation is essential, and that 2 Hz topographic scattering is small compared to the basin response.
Shake-Table Comparison Tests of the Wilcoxon 731-4A and Kinemetrics FBA-23 Accelerometers:
The accelerometer manufacturer, Wilcoxon Research, Inc., has developed a piezoelectric accelerometer, the 731-4A, having sufficient sensitivity and low enough internal noise to be useful as a seismic instrument. Recently, Pete Rodgers and Scott Swain of ICS have incorporated this three component accelerometer into both a surface and borehole installation north of Webb Hall. The Wilcoxon is particularly useful in boreholes because the horizontal components do not require precise leveling.
In order to check the linearity of the Wilcoxon 731-4A versus acceleration amplitude, it was mounted on a shake-table together with the more familiar Kinemetrics FBA-23. The tests were conducted component by component, i. e. the two verticals were shaken together along their sensitive axes and the two horizontals were shaken together in the same fashion. The results were that in the range 0-0.5 g's both the vertical and horizontal Wilcoxons track the corresponding Kinemetrics to better than 1%.
In order to compare the dynamics of the two accelerometers, they were again mounted together on the shake-table.
As before, the verticals and the horizontals were tested separately as pairs.
The input excitation from the table was a random acceleration flat over the frequency range 1 Hz to 100 Hz with an rms amplitude of 0.1 g.
The similarity between the two outputs which resulted from the application of a random acceleration was measured by computing the normalized spectral coherence, r, as a function of frequency.
The fact that, for all the tests, r was nearly exactly equal to one indicate that the Wilcoxon 731-4A and Kinemetrics FBA-23 accelerometers yield nearly identical dynamics over the frequency range 1 Hz to 50 Hz.
Thus these results indicate the Wilcoxon 731-4A is a useful seismic sensor for many applications.
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