Quarterly Newsletter Volume 4, Number 1 Southern California Earthquake Center

3 Precarious Rocks Record Seismicity

6 Interview: Jean-Bernard Minster

12 Research in Progress: San Joaquin Hills

16 SCEC News Briefs

21 1998 SCEC Research Program and Projects

26 Feature: Charles Richter

S C EE C Page 2 S C E C Southern California Earthquake Center

From the Center Directors . . . Earth Science Research Needed for Earthquake Hazard Reduction

Center Director Science Director

As the science director of SCEC, I am often asked what earthquake science can do to reduce earthquake hazards and what research tasks are most important in this endeavor. The statement below addresses those questions. Comments are welcome. Please bear in mind that this statement is not meant to represent the entire SCEC research agenda. The statement addresses a practical problem—how to protect lives and property. The SCEC research agenda must address this problem while also fostering fundamental discovery that may or may not reduce hazards. Furthermore, the practical agenda below must involve national and international partnerships well beyond the SCEC boundary. —David D. Jackson

ffective reduction of small and large earthquakes; have been sites of abnormally Progress requires close earthquake hazards and strain rate measurements severe effects in recent earth- cooperation between earth E requires assessment of with GPS and other techniques. quakes. However, we lack a scientists and engineers. Our the hazard, identifying options comprehensive theory that understanding suffers from A critical need is to test ideas for protecting people and explains why, and we cannot lack of specific knowledge of about earthquakes. For structures, assessing the yet distinguish well between ground motion at sites where example, the size of future effectiveness of these options, site effects and unique features damage has occurred. We have earthquakes may be limited by prioritizing mitigation, and of earthquake rupture. Some settled for overly simple readily measured quantities selling the program. First, we answers will come from descriptions of ground motion, like fault length. The earth- must attack the elements of the modeling the reverberation of such as Modified Mercalli quake potential may also be hazard that can be mitigated seismic waves in sedimentary Intensity or peak horizontal strongly affected by stresses most economically. This is basins. But we need many acceleration. Damage also from previous large earth- where the earth sciences play recordings of individual depends on the duration of quakes. We cannot adequately an essential role. Predicting earthquakes as well as record- strong shaking, its frequency test these ideas locally because times of individual earth- ings of many earthquakes at content, etc. large earthquakes are so rare. quakes does not appear individual sites to distinguish An effective strategy must possible in the foreseeable between source and site effects. To understand damage better, include international coopera- future, so an effective approach seismologists must provide a tion so that earthquakes Getting the necessary data will to risk reduction must focus on more complete description of everywhere on earth can be require new seismographs and long-term earthquake poten- motion, including a “time used to test the most important future earthquakes. We can tial. To fulfill their role, earth history” or seismogram, at sites hypotheses. accelerate our learning by scientists must answer three where damage has occurred international cooperation. important questions. What level of ground shaking, but no recordings were made— Helping to install modern i.e., interpolate readings from landslides, and liquefaction seismic arrays in Japan, New will these earthquakes cause? seismograph locations to the Where will earthquakes occur Zealand, and other hotspots locations of structures. and how large could they be? The effects of earthquake could bring us needed data An adequate solution requires shaking depend on the size Studies of active faults, records sooner. We cannot afford to new data on ground shaking and complexity of fault of past earthquakes, and waste a single earthquake. and building response. rupture, reverberation and measurements of distortion of Research is needed to develop focusing of seismic waves, and the earth’s crust help to define What is the relationship computer models of ground the local soil conditions. Earth earthquake potential. The between ground shaking and shaking, test them against scientists contribute greatly to greatest need in earthquake damage to structures? existing data, and apply them safety by identifying site hazard assessment is for basic Seismic wave trains are made to estimate the ground motion characteristics that contribute data on faults and earthquakes. complex by reverberations that caused damage. A strategy to damage, independent of the We need mapping and seismic within the crust. To develop to estimate ground motion and particulars of earthquakes. imaging of faults; fault and prioritize protective building response together will trenching to find dates and Young sedimentary sections, measures, we must know how vastly improve our ability to sizes of prehistoric earth- margins of sedimentary basins, long and how strong the waves optimize and sell an earth- quakes; seismic recordings of and other topographic features must be to cause damage. quake mitigation strategy.

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 3

Precarious Rocks May Help Estimate L.A. Basin’s Seismic Hazard By Jill Andrews

from data gathered on much earthquakes in northern What’s a Precarious Rock? smaller earthquakes—and are Nevada, no delicately balanced therefore uncertain. Various rocks were found. Rock Out in the field, the initial judgment of precariousness is hazard maps for California “aprons” on steep sidehills relatively easy: the rocks look as though they could be toppled (including the SCEC “Phase II” “showed instability, including by relatively low accelerations. hazard map) depend on these mixtures of rocks with fresh In addition, they have to be in uncertain extrapolations, and surfaces that lack desert a position so that once toppled, according to Brune, there are varnish, rocks that have been they would not return to an no known field methods other flipped over with dark varnish unstable position with further than the use of precarious on the bottom and red oxide shaking. In most cases, the rocks to test these extrapola- (typical of the underside of rocks are also not the result of tions. rocks) on the top, and abun- having recently fallen dant rocks with multiple Brune’s methods for studying downslope or accidentally impact marks.” precarious rocks use observa- ending up where they are. tions of rock varnish (a dark, Ground accelerations necessary Quantitatively, the acceleration uniform finish) to assess how to topple some precarious required to topple a rock is long they have been in place. rocks can be estimated with roughly proportional to the Rock varnish, combined with stability calculations, force tests tangent of the angle between local geomorphic evidence, can in the field, and artificially vertical and a line from the help establish the approximate induced ground motion. In center of mass to the base length of time precarious rocks addition, studies of areas of rocking point, multiplied by have been in their present recent high ground motion the acceleration of gravity positions. For example, in a further calibrate the methods (Wiechert, 1994). study he conducted in the (Brune, 1992). A statistical vicinity of known historic study of a number of rocks is

ames Brune’s 1998 SCEC- percent the force of gravity) or funded research project, less. Significant damage to About the researcher: James N. Brune is director of the Seismo- J“Study of the Toppling older buildings begins at this logical Laboratory at the Mackay School of Mines and professor of geophysics in the Department of Geological Sciences at the Accelerations of Precarious level. University of Nevada, Reno, a SCEC core institution. Brune is Rocks on a Profile Perpendicu- For comparison, the Southern the recipient of numerous honors and awards, including the 1997 lar to the San Andreas Fault for California Earthquake Center Seismological Society of America Medal, an award given for sci- Constraining Strong Motion produced a hazard map entific contributions that bolster the overall field of earthquake Attenuation Relationships for showing the number of times science and engineering. Great Earthquakes,” is an per century the shaking from innovative approach to earthquakes will exceed 20 When presenting the medal to Brune, Ralph Archuleta, president earthquake hazard assessment. percent the force of gravity. of SSA, pointed out that Jim’s mentors, colleagues, and students His studies of precariously Cast in probability terms, the have “universally commented on his deep intuitive approach to balanced rocks may provide same analysis predicts that the addressing fundamental problems. Phrases such as ’extraordi- important quantitative greater southern California nary intuitive sense,’ ’incredible strength of intuition and sharp- constraints on ground motion region should experience a ness of reasoning,’ and ’remarkable physical insight’ are used to from large earthquakes in the magnitude 7.0 or greater describe his approach to science.” last few thousand years (also earthquake about five times see Brune, 1994). each century. Brune and his colleagues recently submitted two papers to Seis- mological Research Letters: “Precarious Rocks Along the Mojave In several areas of Nevada and Since the most recent great Section of the San Andreas Fault, California: Constraints on California there are many strike-slip earthquakes along Ground Motion from Great Earthquakes,” and “Probabilistic Seis- precariously balanced rocks— the San Andreas fault occurred mic Hazard Analysis without the Ergodic Assumption” (with rocks that have been in place in 1857 and 1906, before the John Anderson). For this article, we’ve abstracted from the first for centuries and could be invention of strong motion paper (with Brune’s permission), including a few photos and fig- knocked down by earthquake instruments, estimates of the ures provided by Brune, to help our readers appreciate one of ground motion with peak earthquake hazard for Califor- the more innovative approaches to seismic hazard analysis. accelerations of about 0.2 g (20 nia depend on extrapolation

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 4 S C E C Southern California Earthquake Center

precarious rocks. The main precarious rocks still standing difference between the PSHA and fewer examples of rocks maps and Wesnousky’s map is that appear to have been that Wesnousky used only the dislodged. mean value for attenuation of Brune sees a clear transition peak ground acceleration with between precarious and semi- distance, whereas the PSHA precarious rocks as the distance maps added a statistical increases from the San Andreas (Gaussian) uncertainty to the fault. The same general ground motion for each conclusion, says Brune, applies magnitude and distance for the distribution of precari- (Stirling et al., 1997). ous and semi-precarious rocks For his SCEC project, Brune to the southwest in the San and his colleagues focused on Gabriel Mountains. rocks near the Mojave section The PSHA maps for the San of the San Andreas fault in the Gabriel Mountains southwest Mojave near Palmdale and in of the San Andreas are con- the adjacent San Gabriel trolled by ground motions Mountains. In these areas, from the San Andreas and the numerous balanced rocks, Sierra Madre frontal thrust estimated to be precarious and along the southern flank of the semi-precarious, were found at San Gabriels (northeast edge of distances between 11 and 35 the greater Los Angeles basin). km from the fault. As a consequence, the PSHA A considerable number occur values for the Frankel et al. at Lovejoy Buttes, 14 to 17 km (1996) and Ward (1996) maps from the San Andreas. An decrease to the south of the San accompanying figure gives the Andreas for distances of only locations of these rocks. At the 10 km, then flatten, and closer distances (Lovejoy increase as the effect of the Buttes and Alpine Buttes) the Sierra Madre fault, dipping rocks are less precarious northeast under the mountains, (“semi-precarious”—see Brune, begins to be felt (see accompa- 1996), and there are also nying figure). Photographs of the types of rocks that are being studied as precarious or semi-precarious. (Photos by numerous examples of rocks James N. Brune) that appear to have been There are three zones of semi- shaken down. At larger precarious rocks in the San necessary to eliminate the anced rocks are effectively distances there are numerous Gabriel Mountains that give influence of accidental occur- strong ground motion rences. More recently, Brune “seismoscopes” that have been and his colleagues have operating on solid rock concentrated on the quantita- outcrops for thousands of Map showing the locations of precarious rocks in James Brune’s study. tive aspects of understanding years, thus providing a limit on precarious rocks through the maximum ground motion comparative studies of that could have occurred numerical modeling and during that time. physical experiments (Baoping Shi et al., 1993). In a 1996 study, he and his colleagues found that the The term “precarious rocks” distribution of precarious rocks needs no explanation when in southern California was not linked to photographs like that consistent with the large values on the cover of this issue. Some of ground motion predicted by of these rocks have been in Probabilistic Seismic Hazard place for thousands of years Analysis (PSHA) studies. He and have remained intact found, with the exception of tesy of James Brune tesy of James through numerous historic and Wesnousky’s 1986 PSHA map, geologically recent earth- all PSHA maps predicted quakes. According to Brune, ground motions larger than

groups of precariously bal- those based on analyses of All figures cour

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 5

Society of America, Boulder, CO, balanced rocks by earthquake, abstract. Bull. Seism.. Soc. Amer., 86:1364– 1371. Bell, John W., J. N. Brune, Tanzhuo Liu, Marek Zreda, and James C. Yount Stirling, M. W., A. Anooshehpoor, J. N. (1998). Dating precariously Brune, and S. G. Wesnousky balanced rocks in seismically (1998), Assessment of site active parts of California and conditions of precariously Nevada, Geology in press. balanced rocks in southern California, Bull. Seism. Soc. Am., Bolt, B. A. (1993). Earthquakes, New submitted. York: W.H. Freeman and Company. Ward, S. N. (1995), A multi-disciplinary approach to seismic hazard in Brune, J. N., J. W. Bell, and A. southern California, Bull. Seism. Anooshehpoor (1996), Soc. Am., 85:1293–1309. Precariously balanced rocks and seismic risk, Endeavor, New Weichert, D. (1994). Omak Rock and the Series 20, No. 4, 1996. 1872 Pacific Northwest earthquake, Bull. Seism. Soc. Am., Brune, J. N. (1996), Precariously 84:2:444–450. balanced rocks and ground motion Above: Comparison of estimates of toppling accelerations of precarious rocks in the Mojave Desert with maps for southern California, Bull. Wesnousky, S. G. (1986), Earthquakes, PSHA estimates (from published PSHA maps) and with approximate mean of mean attenuation curves derived by various authors. Numbers in the circles are the number of rocks found to give reliable Seism.. Soc. Amer., 86:43–54. Quaternary faults, and seismic estimates of toppling acceleration. hazard in California, J. Geophys. Frankel, A., C. Mueller, T. Barnhard, D. Res., 91:12587–12631. Below: Same information for the San Gabriel Mountains. Perkins, E. V. Leyendecker, N. Dickman, S. Hanson, M. Hopper Wesnousky, S. G. (1994), The (1996). National Seismic Hazard Gutenberg-Richter or Maps, June 1996, U.S. Characteristic earthquake Department of the Interior, U.S. distribution—which is it?, Bull. Geological Survey, MS 966, Box Seism. Soc. Am., 84:1940–1959. 25046, Denver Federal Center, Denver, CO 80225. Working Group on California Earthquake Probabilities (1995), Seismic Shi, B., A. Anooshehpoor, Y. Zeng, and hazard in southern California: J. N. Brune (1996), Rocking and probable earthquakes, Bull. overturning of precariously Seism. Soc. Am., 85:1994–2024.

SCEC Workshop on Physics, Future The Southern California Earthquake Center is hosting a workshop on the physics governing the behavior of earthquakes and faults. The workshop will be in Utah from June 21 through June 23, 1998. The objective is to assess the current state of understanding of the earthquake process. There are many approaches to such problems including continuum mechanics, statistical physics, laboratory preliminary estimates of thrust, and also provide experiments, and field observation. By bringing together experts toppling accelerations. Brune’s important limits on ground in these various approaches, we hope to compare results and conclusion is similar to that for motion input for calculations of identify key problems for future research. the Mojave Desert data: the seismic response of the Los This workshop is timely as the staff works toward renewing SCEC disagreement with the “2% in Angeles basin. as the new California Earthquake Research Center. A primary 50 yr” maps. objective of the workshop will be to produce a list of key prob- Related Research lems and proposed methods of approach that can be incorporated His preliminary results from into the renewal proposal and guide the center’s strategic plan for Anderson, J. G., and J. N. Brune the San Gabriel Mountains earthquake physics research. A second objective will be to identify support the conclusion that the (1998a). Methodology for using precarious rocks in Nevada to test important directions and modes of interaction between the Frankel and Ward mapped various SCEC/CERC groups. accelerations are too high. seismic hazard models, submitted for publication. Further study of the precarious New Web Address for USGS Seismic Bulletins rocks in the San Gabriel Anderson, J. G., and J. N. Brune Mountains, says Brune, may (1998b), Non-ergodic probabilistic The web address for the Southern California Seismic Network provide important limits on seismic hazard analysis, annual Bulletins under the USGS Web Sites heading has changed slightly. ground motion from the frontal meeting of the Seismological It is now: HTTP://WWW-SOCAL.WR.USGS.GOV/LISA/NETBULLS.

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 6 S C E C Southern California Earthquake Center

Interview with SCEC scientist . . . Jean-Bernard Minster

SCEC Quarterly Newsletter in- physics, and geology led me to to the French Atomic Energy cludes interviews with SCEC geophysics. Commission. scientists to highlight the I graduated in 1969 from the SQN—Is that where interviewees’ research projects School of Mines of Paris with a you started your work with and interests. We also discuss degree in mining engineering nuclear test monitoring? other projects and subjects to and simultaneously from the give a view of the scientist as par- JBM—No, I started French Petroleum Institute, ticipant in the larger scientific that during my Ph.D. work. which I also attended in my Bernard Minster community and society in gen- Some of the applications of my last year, with a degree in eral. In this issue, SQN inter- Ph.D. research had to do with petroleum engineering. opportunity to join S-Cubed in views the vice-chair of SCEC’s nuclear monitoring. At that San Diego as Program Manager board of directors and eminent SQN—Why did you time I was already involved in for Theoretical Geophysics. geophysicist Bernard Minster. come to the U.S? joint research with Systems, Science and Software (S- SQN—Why did that JBM—Though my SQN—Will you Cubed), the company I joined draw you away from Caltech? professors in France tried to describe your educational in 1980. We did a lot of discourage me at the time, I felt JBM—I had always background in France? numerical modeling of ready to “see the world” and earthquake and explosion wondered whether I was the applied to graduate school in JBM—In the French sources. kind of person who could system, the best high school the U.S. I was turned down by make it in the private sector. I students have the option to Pittsburgh and Salt Lake City SQN—Did you return decided that that was the time take an extension of high but accepted by Caltech. At to the U.S. immediately after to try it rather than waiting school for two or three years Caltech I was introduced to your military duty? until I retired. Besides, the idea called “preparatory classes.” seismology by my advisor, of living near the beach in San JBM—After only one During that time, they take Prof. Charles Archambeau. Diego held considerable year in France, I decided that intensive math, physics, and attraction! As far as I am concerned, I was my sweetheart in the U.S. was chemistry, languages, and extremely lucky, not only to the girl to marry, and I asked other things to prepare for a SQN—Did you make have the kinds of professors her to wait an extra year for nationwide competitive it in the private sector? and mentors that the Caltech me. I came back a few days examination for engineering JBM—I did pretty schools. At the end of the well. However, after three second or third year, they take years, the company went the exam for admission to My experience in the private sector taught me that heavily into the “Star Wars” engineering schools. It’s very fundamental science and commercial interests are type of research. I thought that different from the standard geophysics and earthquakes university path. It’s very not altogether incompatible. It also taught me had little to do with that, so a competitive. something about myself: even though I can work couple of partners and I left the Out of 2,000 applicants, I was well in a commercial environment, I missed the company and formed Science one of 60 accepted to the Horizons, Inc. School of Mines of Paris. It, interaction with graduate students, the intellectual We worked for four years together with the Ecole challenge. together to develop a variety of Polytechnique and the Ecole things, but mostly database Normale Superieure, is one of and data analysis systems for the top engineering schools in treaty verification. Our main the country. They are also Seismological Lab has to offer, before Christmas in 1975. We business was twofold: (1) to located in Paris. but also the exceptional fellow were married in March 1976. I develop seismic data analysis graduate students at the lab was lucky enough to get a job systems on workstations (SUN SQN—What first who taught me how to do in the U.S. at the time. workstations were then interested you in earth science? research in cooperation with emerging as major players on others. These are friends I will SQN—Where did you the market) and (2) to develop JBM—I had a basic keep for life. work after returning? education in math and physics. real-time digital data transmis- At the School of Mines, I was I graduated in 1974 and had to JBM—I was an sion and acquisition systems exposed to geology, which I return to France to meet my assistant professor and then an for seismic stations and arrays loved. However, trying to military obligations. I served in associate professor at Caltech. (such as ARCESS in northern reconcile my interests in math, the French Air Force, detached In November 1980, I had an Scandinavia).

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 7

Our customers were primarily applied and was accepted, so I Professional Highlights DARPA and the U.S. Air Force, didn’t even have to move. I but we also had a few commer- was a visiting professor from BERNARD MINSTER cial customers—in spite of the 1987-89. In 1989, I applied for severe cutbacks in the oil and received a permanent industry at that time. faculty position with the Education University of California at B.S., Mathématiques—Académie de Grenoble We were using some of the first Scripps Institution of Oceanog- Graduate, Ingénieur Civil—École des Mines de Paris UNIX workstations. S-Cubed raphy (SIO). Graduate, Ingénieur du Pétrole—Institut Français du Pétrole bought one of the first models Ph.D., Geophysics—California Institute of Technology ever built by Sun SQN—Why Scripps? Doctorat d’État, Géophysique —Université de Paris VII Microsystems. It had serial What are your interests there? number 99. We got to demon- JBM—I am extremely Professional strate its use at the United interested in the University of Systemwide Director, Institute of Geophysics and Planetary Physics Nations in Geneva. It was California as a fundamental Professor, Scripps Institution of Oceanography, UCSD really exciting. It was a component of higher education Associate Professor, California Institute of Technology highlight of my life in the in the state of California and as private sector. the producer of a large work Honors SQN—Why did you force with an advanced Nordberg Lecturer, Goddard Space Flight Center leave the private sector? education. Fellow, American Geophysical Union Cecil and Ida Green Scholar, IGPP JBM—In 1987 I left I feel very fortunate to be a Science Horizons mostly member of SIO, the leading Recent Research Subjects because I missed the interac- institution of this kind in the • Determining the structure of the Earth’s interior from broadband seismic data; imaging the Earth’s mantle and crust using seismic waves. • Use of seismic means for verification of nuclear test ban treaties. I think it’s fair to say that nuclear treaty verification • Application of space-geodetic techniques to study tectonic and has been a tremendous boon to seismology since volcanic deformations of the Earth’s crust. • Ionospheric disturbances caused by earthquakes, rockets, mining the early 1960s in both fundamental research and blasts, and other explosions, using GPS. • Validation of earthquake prediction methods based on pattern the development of technology. recognition techniques. Recent Publications Ridgway, J. R., J. B. Minster, N. Williams, J. L. Bufton, and W. B. Krabill, tion with students. The U.S.—and the world. I feel a Airborne laser altimeter survey of Long Valley, California, Geophys. company has since continued profound allegiance to IGPP, a J. Int., 131, 267-280, 1997 to flourish and diversify. multi-campus research unit of Hofton, M. A., J. B. Blair, J. B. Minster, J. R. Ridgway, N. P. Williams, J. L. the University of California. It My experience in the private Bufton, and D. L. Rabine, Using laser altimetry to detect topographic embodies excellence in sector has been a very good change at Long Valley caldera, California, Earth Surface Remote research in all disciplines of the Sensing, SPIE, 3222, 295-306, 1997. one. It has taught me that geosciences, from the study of Shkoller, S. and J. B. Minster, Reduction of Dietrich-Ruina attractors to fundamental science and ancient life to the study of unimodal maps, Nonlinear Processes in Geophysics, 4, 63-69, 1997. commercial interests are not black holes, to archeology, Calais, E., J. B. Minster, M. A. Hofton and M. A. H. Hedlin, Ionospheric altogether incompatible. It also seismology, mantle convection, signature of surface mine blasts from Global Positioning System taught me something about ocean and atmospheres of measurements, Geophys. J. Int., 132, 191-202, 1998. myself: even though I can work various planets, magneto- Xu, H., S. M. Day and J. B. Minster, Model for nonlinear wave propaga- well in a commercial environ- spheres of planets and stars, tion derived from rock hysteresis measurements, J. Geophys. Res., ment and although I can and any number of intermedi- submitted, 1998. appreciate the drive surround- ate disciplines. ing a for-profit research endeavor, at the end of the day, blockbuster technique of the operating at both L and C band I prefer to work with students SQN—Do you still 1990s is Synthetic Aperture (hence the name ECHO-Elsie), in an academic environment. I have a connection with the Radar Interferometry. Our dedicated to the study of (1) missed the interaction with French space program? proposal is for the Earth the earthquake cycle, (2) the graduate students, the intellec- JBM—We have just Change and Hazard Observa- volcanic cycle, and (3) the tual challenge. submitted a “step 1” proposal tory Synthetic Aperture Radar cryosphere. Of course it will be I was lucky that a visiting to the NASA Earth System satellite. able to do a lot more. Our professorship opened at the Science Pathfinder (ESSP) intent is to build on the Institute of Geophysics and program of small low-Earth It is proposed as a bilateral phenomenally successful Planetary Physics (IGPP). I orbit observation satellites. The U.S.-French instrument European ERS 1 and 2,

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Japanese JERS, and Canadian the radar system. We would the Scripps Institution. In my SQN—How did your RadarSat missions, with a share the ground system and position at UCSD, I am private sector experience mission dedicated to science the data management and responsible to the branch influence your career and your applications. distribution system. It’s a very director. But when it comes to outlook on earth science? good arrangement. multi-campus research When we proposed this before, JBM—I think it gave authority, he’s responsible to we received a very good me a broader outlook. Some me. That’s what makes it people who function only complicated. within the academic environ- SCEC has been an incredibly successful en- SQN—You are ment do not necessarily have a described as a “founding realistic view of how the deavor. A lot more successful than I as an indi- father” of SCEC. Can you private sector works—the vidual had expected in the early years. I think that describe the early planning, the motivations, the procedures, issues you faced, the discus- and expertise available there. we, collectively, should be very proud of what we sions, the policies decided on In my case, it was a very useful back in the late 1980s? exposure to another side of the have wrought. world. JBM—SCEC was created at a time when “the SQN—To what extent idea was ripe and timely,” as is were the hardware and science review, but we were SQN—Can you the idea of a statewide effort software of treaty verification over the budget guidelines. briefly explain the relationship now. I was not part of the directly applicable to seismic This time, we are proposing it among the UCSD, Scripps, and earliest planning, because I was research? as a bilateral mission with the IGPP? out of town—at sea, actually— French Centre National JBM—It’s all very JBM—To an outsider, at the time. The important d’Etudes Spatiales (CNES). The much the same. It’s very it must seem incredibly discussions and policies had idea is to put together some- scientifically based. The complicated. The university mostly to do with the collec- thing patterned after TOPEX/ scientific researchers in the has nine campuses. UCSD is tion, management and distri- Poseidon, an oceanographic private sector and the scientific one of those campuses. UCSD bution of data, and with the altimetry mission that has been researchers in academia is divided into three major issues of making these data extremely successful. We’re exchange views and publish units—the Main Campus, the available to all and selecting proposing to do something papers together and do School of Medicine, and the research directions that would similar for land surfaces using research together. Ever since Scripps Institution of Oceanog- advance the science of earth- Synthetic Aperture Radar. the mid 1960s that’s been true. raphy. The graduate depart- quakes. In fact, I think it’s fair to say According to the rules of the ment of Scripps is an academic SQN—Can you that nuclear treaty verification ESSP program, I would be the department of UCSD. This is describe the early work on the has been a tremendous boon to PI, with deputy PIs Howard where my professorship is Master Model? seismology since the early Zebker at Stanford, Paul Rosen held. 1960s in both fundamental at JPL, and Didier Massonnet UC also has what are called at CNES. The cost to the U.S. Multi-Campus Research Units would be under $120 million, (MRUs) organized research which is far lower than any of We have such an excellent team, it would be sinful units that cover more than one the other missions I mentioned campus. IGPP is one of those. (each one cost well over half a for us not to come up with a very good proposal. IGPP has branches at UCLA, billion dollars). It would be less UCR, UCSD, and at Los than the movie Godzilla cost! Alamos National Laboratory research and the development And it would be dedicated to and Livermore National of technology. science. JBM—The basic idea Laboratory, which are man- behind the “Master Model” Our French partners are very aged by UC. Those five was Keiiti Aki’s. My only This is a model of how generously offering a launch branches make up IGPP. Each contribution was to devise a government and policy on an Ariane 5 booster. ECHO- branch has a branch director. I graphical representation that requirements can drive Elsie would be a piggyback am the systemwide director of people could relate to. This scientific research in a way mission on another French IGPP. happened in the course of a that’s extremely constructive. mission, so we can take two-hour discussion in Kei’s Specifically, we were working advantage of the enormous lift It becomes a little more office. This was one of these under the excellent guidelines capacity of the Ariane 5. The complicated at the level of the wonderful situations where all developed by the Department French would provide the UCSD campus. The IGPP of a sudden everything clicks of Defense to support and launch and the technology for branch at UCSD overlaps with and all the concepts come promote the interaction among a very precise orbit determina- Scripps. John Orcutt, the together into a paradigm that basic research, technological tion and control. The U.S. branch director of IGPP is all participants can understand development, and actual would provide the satellite and responsible to the director of and subscribe to. application.

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 9

From the time of my Ph.D. could we do a good job on a SQN—Time is right ingredients on the table, thesis work, I have had a more mysterious one? something that most SCEC you still need a good chef. continuing interest in treaty researchers seem to have little SQN—Is India, then, SQN—Who’s going verification. In the 1970s I of. Does that mean that more of a test case for international to be the chef? worked on source theory and the burden of keeping an eye verification? on attenuation of seismic on the big picture falls on you JBM—I believe that waves. In the 1980s I worked JBM—“Test case” is and others in administrative we have the leadership right on discrimination between not the term I would use. I positions? now, primarily Tom Henyey single explosions and so-called would say that this calibrates and Dave Jackson along with JBM—I think that’s a “ripple-fired” mine and quarry the challenge at hand in the the scientific leaders in fair description of the job of explosions. My colleagues context of a worldwide northern California. We have anyone who accepts that some Michael Hedlin and John comprehensive nuclear test ban such an excellent team, it fraction of his or her time will Orcutt have played a very treaty. would be sinful for us not to important role in this area. come up with a very good proposal. More recently, I have been working with colleague Eric The study of natural Earth systems is intimately Now whether this proposal Calais on the excitation of involved in public policy and the economy of the wins when compared with acoustic and gravity waves in competing proposals is an the ionopshere by seismic world. We cannot avoid that, but we have not quite unknown. There are many sources. It turns out that even a areas of science where we get moderate-sized quarry blast (3 come to grips with it. excellent people competing. It’s million pounds of ANFO OK to lose to excellent com- explosive, or about 1-2 Ktons) petitors. It’s not OK not to will excite ionospheric distur- SQN—You were a be devoted to administrative produce the best proposal we bances as strong as a fairly founder of SCEC and are vice- duties. It’s very true, for can. large shallow earthquake (e.g., chair of the board of directors. instance, of both directors of SQN—Will space- Northridge). This research is How does your IGPP work SCEC. based activities and research still very immature, but we interact with your SCEC Tom Henyey, for instance, is play a more prominent role in have shown that GPS signals participation? excellent at understanding the “see” these ionospheric waves the program of the new bits and pieces but also the very handily. In this respect the JBM—It’s all one big statewide earthquake center, if bigger picture and bringing it SCIGN network, which SCEC project. Intellectually, we want it is funded? to understand earthquakes in to the rest of SCEC. Tom is a spearheads, will provide us JBM—Definitely. I the sense of a process; if we superb director of SCEC, and if with critical data sets. think that remotely sensed data understand the process better, we ever have a California-wide are going to be critical in the maybe some day we can detect center, he would be an excel- SQN—Do events next generation of models for or identify aspects that have lent director for that center. such as the nuclear testing earthquake processes. precursory capabilities. recently done by India and Similarly, Dave Jackson, as Basically, what we want to do Pakistan have an effect science director of SCEC, has is to understand the physics of SQN—How do you ultimately in seismic research? given us a sense of scientific earthquakes. direction that is essential for see the future of the new JBM—What hap- center? What will it look like, Right now, we understand bits such a diverse center to pened in India is very challeng- what will it be doing, and what and pieces. As time goes by, we function well. He is devoting a ing. Though not a big event, it will it have accomplished in understand more bits and more considerable fraction of his life is located in an area that makes 2010? pieces. My view is that what to this endeavor, at substantial analysis very difficult because we want to do is understand personal cost. JBM—The new center the regional earth structure is the whole. will take advantage of major very complicated and the new advances in observational distribution of seismic stations SQN—Speaking of a technologies, computational is not ideal. SQN—Will the bits statewide center, do you think and pieces become a whole? there will be one? capabilities, and in digital Yet it is an extremely important communications. The data we event. There’s no question JBM—I wouldn’t be JBM—If the proposal have painstakingly collected about that. It gives us a wake- in this business if I didn’t looks good from a scientific over all these years will be up call: we have to keep believe that. It’s true in all the point of view, it would be assimilated in physically based working on improving the sciences that you always work reasonable for the National models, which will offer a technology, improving the on bits and pieces. The Science Foundation to fund it. mechanism for step-wise science, improving our ability important thing is that you We still have to write a very predictions of the state of the to detect, analyze, and identify devote some time to taking good proposal. That hasn’t yet geological systems, and such events. If we didn’t do a stock to see how the pieces fit been done. All the ingredients therefore offer a clear way to good job on this one, how in the bigger picture. are there, but even with all the test the hypotheses we can

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 10 S C E C Southern California Earthquake Center

Minster on Space Geodesy

In the 1970s my best friend Tom Jordan (now a professor at MIT) aircraft navigated by GPS, the Space Shuttle, or a free-flying and I worked on the determination of plate motions from spacecraft. geological data, such as ocean floor magnetic anomalies, transform fault bathymetry, and earthquake fault plane solu- Precise laser altimetry is becoming a practical geodetic tech- tions. This work yielded plate kinematics models valid for the nique. It is much more effective than radar altimetry over land past 2-3 million years. because the slopes are much steeper than over water (which really hurts radar techniques) and because the footprint is much In the late 1970s and early 1980s, a new discipline came to the smaller (tens of meters instead of several kilometers). With fore: space geodesy. The techniques that were developed first precise GPS-determined orbits, we can now conceive of repeat- included Very Long Baseline Interferometry (VLBI) and Satellite pass crossover analysis that should detect slow changes in the Laser Ranging (SLR). When NASA started its Crustal Dynamics total volume of polar ice sheets, a proxy for global climate Project, we wrote a proposal that was accepted and we became warming. The Geoscience Laser Altimetry System, the instru- part of this tremendously exciting revolution in geodesy. The ment for the ICESAT mission to be launched in July 2001, will do magic of space geodesy is that you can “see” plate tectonics just that among other things. I am a member of the ICESAT essentially in real time and can compare the estimates of plate science team. motions for million-year averages and for 5-year averages. Airborne applications include mapping volcanic inflation. An In the late 1980s, a technique that was first proposed nearly a example is Long Valley Caldera, near Mammoth Lakes, CA, decade earlier by Peter McDoran and colleagues become a where we have been flying laser altimetry missions using NASA practical geodetic tool. GPS precise geodesy had come of age. It aircraft since 1993. Airborne experiments are a crucial part of blossomed in the early 1990s with the advent of the Permanent getting ready for a space mission like ICESAT. GPS Geodetic Array in southern California, as well as similar dense GPS networks in Japan, as well as with the creation of the So far, we have been able to demonstrate reliable altitude International GPS Geodetic Service (IGS) of the IAG. determination for well-surveyed surface features at the 2-3 cm level. For example, we can see the slope of the geoid in the I participated in these exciting endeavors with a sense of awe surface of Lake Crowley, over distances of 1-3 km. My colleagues that has not abated and feel that they have brought to the earth Jeff Ridgway, Michelle Hofton, and Nadya Williams have been sciences a remarkable injection of high-tech applications that instrumental in this effort, together with an entire crew of NASA have resulted in a thoroughly renewed outlook on earth defor- Goddard Space Flight Center and NASA Wallops Flight Facility mation measurements at all scales. The use of continuous GPS scientists and engineers. arrays for studying earthquakes is a major SCEC activity, with strong worldwide leadership from Yehuda Bock, Bob King, Dave The study of earthquakes should really involve all phases of the Jackson, Ken Hudnut, and Frank Webb, among many others. “earthquake cycle,” from the co-seismic, to post-seismic, to inter- Since 1993, I have also been involved in precise airborne and seismic, to pre-seismic portions of the cycle. Different physical spaceborne laser altimetry. We are talking about measuring the phenomena dominate different portions of the cycle. Seismology, altitude of the Earth’s surface to an accuracy of about 20 cm, per se, “sees” mostly the co-seismic phase. Geodesy and other over a footprint of 1 m to 70 m, by measuring the roundtrip measurements see the other portions, which are much subtler and travel time of a short pulse of light (1 nanosecond long) from an which involve much longer time scales.

derive from what we already to work on the same problem to start looking at probabilistic JBM—No, there is not know. from different angles—to listen hazard assessment, but the a single argument against that. and to hear from people in the logical evolution is toward a I think that everybody agrees SQN—Since you were other disciplines. SCEC also more profound understanding that it would be beneficial to involved with SCEC from the provides the infrastructure to of the physics that govern have a physical model. But not proposal stage to now, has deliver critical education and probabilistic assessment. That everybody agrees on the SCEC fulfilled your vision of outreach, linking the high-tech means moving toward what ingredients of a physical what it would and should be? side of the science to the we call a physical master model. JBM—SCEC has been practical side. I think that we, model. an incredibly successful collectively, should be very We have ideas. Some of us endeavor. A lot more successful proud of what we have have very strong ideas, but we than I as an individual had wrought. SQN—Is there any don’t know what the model expected in the early years. It disagreement among your will be ultimately. I think we all has brought people together It is, however, time for SCEC to colleagues about the need for a agree, though, that this is the from very different disciplines evolve. It was logical for SCEC physical model? natural evolution of our notion

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 11

The Trojan Horse of what a model should be to predictability. We came to SQN—Should Might Have Been an allow us to understand the understand this after we earthquake prediction be one earthquake phenomenon started looking at global of our goals? Earthquake better. modifications of the planetary system—due to natural causes JBM—It should most “Don’t blame sneaky Greeks in a SQN—What is your or possibly to anthropogenic emphatically be one of our hollow horse for breaching ancient current workload? causes. In that sense, our goals. If there is a chance of Troy’s defenses. Don’t look to besieg- JBM—Right now, I science has perhaps more success, we should pursue it ing armies to explain Jericho’s re- am spending a lot of time on profound implications in terms vigorously. peated destruction. Don’t ask who of public policy than most buried some of the Dead Sea scrolls. issues of the Senate of the There are many facets to this sciences have. It’s true in terms Impersonal earthquakes—not hu- University of California (I chair problem. For instance, we of how we deal with societal man violence—may have done the the systemwide Committee on know that someday there will response to natural disasters. job.” —Robert C. Cowen, Chris- Planning and Budget). I also be a large earthquake under spend much time on IGPP, tian Science Monitor Look, for example, at the Tokyo. The same is true with where I am the systemwide tremendous success of volca- Seattle, San Francisco, Los A recent article in The Christian director. This takes about 50% nology in the case of Mt. Angeles, Mexico City, and Science Monitor discussed of my time. Pinatubo. Look at the tremen- many other major metropolitan geophysicist Amos Nur’s new Then I am involved in develop- dous impact of natural areas. We don’t know how to look at ancient eastern Mediter- ing major proposals such as phenomena such as hurricanes say when, but we know that it ranean history. Where archae- ECHO-Elsie. In addition, I am Hugo and Andrew, or earth- will happen. In that sense, we ologists see mainly the remains a player in the “General quakes at Loma Prieta, have the responsibility to make of warfare and pillage, he sees Earthquake Model” (GEM) Northridge, and Kobe on the sure that we can clearly state seismic destruction. proposal to the NSF KDI insurance industry. You can see the consequences when large program and a co-investigator that the study of natural Earth earthquakes strike. He has also taken a new look at in another KDI proposal on systems is intimately involved the region’s seismicity. Accord- For instance, if there were a multisymplectic integrators to in public policy and the ing to conventional theory, large earthquake near deal with nonlinear natural economy of the world. We quakes occur independently Singapore, there would be systems. And, of course, I am cannot avoid that, but we have here and there along a fault major consequences—not only teaching and doing a bit of not quite come to grips with it. line as accumulated strain is for Singapore, but for the research (mostly through released in local areas. Instead, What we need to do is to come worldwide economy. There colleagues and students). This Dr. Nur sees evidence that to grips with this reality as a would be major consequences accounts for the other 100% of devastating quakes can occur community—a scientific for the enormous U.S. assets in my time. in swarms that can unzip an community—and identify the that city. We need to be entire fault line. Swarms would areas where we can have some SQN—You seem to sensitive to this and not think be separated by long periods of reasonable positive impact, have a view of earth sciences in just about seismology. quiescence, lulling inhabitants based on scientific discourse a larger context that includes into false security. and scientific facts. I think that this is where politics and economics. Can organizations like SCEC can Nur, who is chair of Stanford you explain your view in that help—SCEC can provide a sense? SQN—Are you University’s geophysics saying that scientists need to be bridge between pure seismo- department, says that such a JBM—Earth sciences aware of things beyond pure logical science and societal swarm may be what ended the in the general sense, by which I science? impact, political science, region’s Bronze Age, when mean the sciences that deal economy. These are not easy dozens of civilized centers— JBM— with Earth systems—the That’s abso- questions to answer or easy including Knossos, Mycenae, atmosphere, the ocean, the lutely right. We need to be goals to achieve. and Troy—were destroyed solid earth, perhaps also the aware of it, and we need to be within a 50-year period. I think we should have as magnetosphere and the sensitive to it. This is particu- broad a discussion as possible. ionosphere, interplanetary larly true in terms of natural If it happened then, it could Ultimately, this debate should space, life on other planets, disasters—hurricanes, torna- happen now. That makes this not be restricted to California— new planets in distant solar does, etc. When it comes to new look at ancient history or even to the borders of the systems—all that body of earthquakes, it becomes dicier. relevant to efforts to under- United States. This is a science has an enormous We can and should prepare for stand earthquake hazards in worldwide problem. Frankly, if amount of input to provide in the anticipated impact of large regions like the Middle East, we look at it on a worldwide policymaking. earthquakes. We have a very where large population centers difficult time when it comes to basis, we will likely make now lie along or close to This has been true ever since earthquake prediction. We progress faster and on a dangerous fault lines. we started understanding that can’t predict earthquakes—not broader front than if we stick to systems the size of a planet even on the short time scales a more parochial point of view. For the full story, see the behave according to laws that over which we can predict the January 6, 1998, Monitor or the give us some degree of impact of hurricanes. Interviewer: Ed Hensley web at WWW.CSMONITOR.COM.

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Featured Fault Seismic Potential of the San Joaquin Hills Research in Progress—An Interview with Lisa Grant

which has been carefully The hills were relatively Lisa Grant (Chapman University) is a mapped through engineering undeveloped then. I could see member of a team of researchers study- geology studies and by the that there was a series of what ing the earthquake potential of the San California Division of Mines appeared to be notches cut into and Geology (CDMG), goes the hillside. They looked like Joaquin Hills in Orange County. The offshore at Newport Beach, marine terraces cut by waves. team expects to submit its findings very where it becomes difficult to So it looked like the San soon after this newsletter goes to press. Dr. study because it is under water. Joaquin Hills had been rising Grant’s coauthors are Karl Mueller (Uni- out of the sea. I wondered SQN—What are the versity of Colorado), Eldon Gath (Earth whether that is true and how features of the area that drew Consultants International), Rosalind old those marine terraces are. your team’s attention to the Munro (Leighton and Associates), San Joaquin Hills? Around that time, many Larry Edwards (University of Min- scientists were trying to LG—There is a series nesota), Hai Cheng (University of understand the Palos Verdes of coastal mesas in the south- Minnesota), and George Kennedy fault. There is a series of ern part of the Los Angeles (San Diego State University). marine terraces—like bathtub basin. Beneath them is a thick rings—around the Palos Verdes Though the findings are not sequence of sediments. The peninsula. By looking at those final and therefore cannot be mesas have been associated terraces, it appeared that the published yet, Dr. Grant with uplift along the Newport- peninsula had been rising. The Photo: Ruth Wardwell Ruth Photo: agreed to an interview to dis- Inglewood fault zone. Farther big question was why was the north in Los Angeles County, cuss the process by which such a project begins and proceeds, as peninsula rising—was the they are localized right along an example of SCEC-funded and SCEC-facilitated interdiscipli- Palos Verdes a thrust or a the Newport-Inglewood fault nary research. strike-slip fault? zone. They’re clearly related to movement of the Newport- I was at Caltech at the time. It SQN—Would you focused not on those older Inglewood fault. was something we were discussing in seminars. Then I describe the area where your surface faults, but on whether As you get farther south, the would go home to the San team has been working? there might be one in the Newport-Inglewood fault goes Joaquin Hills and think that it subsurface. Initially, we had offshore, and the mesas get LG—The San Joaquin looked very similar. I asked, little to go on other than a broader and higher. Then they Hills are located in southern “What about the San Joaquin combination of intuition and turn into the San Joaquin Hills. Orange County at the south- Hills?” No one knew. No one circumstantial evidence. We That’s one of the first things I western margin of the Los had looked that closely. That were suspicious that something noticed when I moved to Angeles basin. Some of the spurred my first interest— was there. Orange County in 1991. most scenic real estate in casually wondering whether southern California is on the SQN—What other coastal side of the San Joaquin research has been done in that Hills near Newport Beach, area? Laguna Beach and Dana Point. LG—The main Geologic maps of the San structure in the area that has Joaquin Hills show many been studied well is the faults. The faults that reach the Newport-Inglewood fault. The surface have been examined by Holocene (active) strand is many geologists, and they fairly close to the coast line, but don’t appear to be active. Some there is a broader zone of older of the faults have moved in the faults that extends inland Quaternary, but apparently not through Costa Mesa and in the Holocene. That’s one of Huntington Beach. Their the reasons that the San locations are not very well Joaquin Hills have previously constrained. Those are mostly been dismissed as inactive mapped from ground water tectonically. Our research barriers. The active trace, Map courtesy Lisa Grant

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the San Joaquin Hills rose out 1993. By then, I was in consult- of the sea during the Quater- ing at Woodward-Clyde; I nary, and if so, why? didn’t think I’d pursue it as a research project. I thought that SQN—What were the if Roz and Eldon weren’t able first steps in finding out? to pursue it at the time, maybe LG—My working Karl would. hypothesis was that they were Then the Northridge earth- rising. To test that, the terraces quake hit. There had been would have to be mapped and subtle evidence that the dated to see whether they had Northridge blind thrust was truly risen relative to sea level. there. It’s not so subtle now, SQN—So you but nobody saw it until after suspected that something the earthquake. tectonic was happening instead In light of that experience and of just changes in sea level? Lisa Grant doing fieldwork in the San Joaquin Hills after the Laguna fire in October 1993. (Photo: Adrian increased sensitivity to blind Schneider, Woodward-Clyde Consultants) LG—Yes. Sea level thrusts, I became fascinated by They had an interest in the In some places mapping the has gone up and down. That what I saw around my own marine terraces; they had terraces was relatively easy. makes it complicated. I wanted home. I had a very personal published about them. Eldon They were all at the same to know if the terraces formed interest in it. I knew that it even had a license plate with a elevation and therefore by changing sea level alone, or would be very important to reference to marine terraces. correlated very well. In other by emergence of the hills due find out if a similar structure They had been collecting data places, mapping became more to tectonic uplift. exists under Orange County. in their project files, but it complicated. It was difficult to In 1992 I attended an AEG wasn’t collected for research. It tell which terraces correlated (Association of Engineering was in consulting reports and with which other ones. I couldn’t stop thinking about Geologists) meeting that in their personal notes. it. I saw clues everywhere. It SQN—How did you offered a field trip to Orange was driving my husband nuts. I asked them if they were assign ages to those marine County. I signed up and that’s willing to point me to the right terraces? data and let me compile it. I LG—That’s where the thought we could test my other coauthors come in. Eldon hypothesis. They were very Initially, we had little to go on other than a brought in George Kennedy interested. At the same time, because they had worked on combination of intuition and circumstantial Karl was independently the fossils in the area. Some of thinking that it was a good the marine terraces had warm- evidence. We were suspicious that something time to pursue the San Joaquin water fossils and some had Hills. We all decided that if we was there. colder-water fossils. In a place all put our heads together, it where we couldn’t tell which would be a better project than terrace was which, the idea any of us could do individu- where I met Rosalind Munro. was that George could look at Every time we went some- ally. And so we submitted She gave a presentation on the the fossils to help us in where, I was looking at companion proposals to SCEC marine terraces on the coastal correlating the terraces. roadcuts. He took me out to in fall 1995. side of the San Joaquin Hills. dinner for my birthday, and I SQN—After your I got very excited; here was just wanted to look at the proposals were approved, That helped us correlate them, someone else who had noticed exposure in the parking lot. He what came first? but we still couldn’t assign them. She’d written an abstract said, “You really have to make ages to them. We mapped and pointed me to another one this a research project. Other- them, but they were just that had been written by wise, it’s going to torment LG—First, we relative. We got stuck then. We several people at her company, you.” compiled the geologic data had to find a way to assign Leighton and Associates, SQN—That sounds about the terraces and mapped some absolute ages. One way is including Eldon Gath. like the turning point. What them. I worked with Eldon and using amino acid racemization did you do to avoid that Roz on the mapping. Karl of all these shells George was Karl Mueller was working on “torment”? compiled archival (before looking at. That process has some structures farther north— development) topographic been used in the San Joaquin the Compton-Los Alamitos LG—I started talking maps in digital form to use as a Hills, producing general ages, fault. I approached him and with Eldon and Roz. They had base for our mapping. He then but there are discrepancies and asked him whether he’d lots of knowledge of the area put our data into a database so disagreements about them. The considered looking at San since they had done much of that he could use it for struc- uncertainty was enough that it Joaquin Hills. That was late the grading for development. tural modeling. wasn’t helping us answer the

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specific questions that we History Foundation of Orange Frank’s coral specimen was a LG—The key to needed for our project. County. He had listed a coral in good large specimen and figuring this out is the one of his species lists. In fact, enabled us to establish absolute multidisciplinary work. I think Because he has done a great he could show me the collec- dates. The amazing thing is that the result is much greater deal of this kind of dating, I tion site since it’s been pre- that the date came out exactly than the individual contribu- asked Dan Ponti of USGS served as a greenbelt. There are consistent with our hypothesis. tions. Each of us has a particu- whether there is another way. still some shells in it, but it is That’s never happened to me lar expertise or knowledge He said that if we could find a probably going to be graded before. base that is complementary to coral, we would have our within the next year. the others. Rosetta Stone. We could date George was able to get another coral with uranium series I asked him if he’d be willing coral but the date came out so Only by all working together methods. We could then tie all to give it to me. He said that far off that we could not think on this were we able to the amino acid data in with accomplish what we did. SCEC some well-constrained dates. facilitated that with its basic working group structure. The But nobody had found corals. Earthquake Geology Working He and his coworkers had been Group talked about various looking for years. That became research problems and my mission. formulated ideas for how to It was like looking for a needle pursue them. I can’t think of a in a haystack. I kept coming up better infrastructure for empty-handed. George knew conducting this work than of some corals, but there was a what SCEC has provided. question about whether they SCEC’s method of funding could be used for dating since projects also helped. We were they are part of a museum able to submit complementary collection. Lisa Grant’s daughter Erika stands at the contact between marine terrace sediments (above) and proposals and have them After my son was born, I had Monterey shale (below). Erika was born during the Landers aftershock sequence. (Photo: Lisa Grant) considered as a package. Other funding agencies have mecha- to spend more time around he’d received several requests of any possible explanation for nisms for doing that, but it’s home and couldn’t do field- for it before and hadn’t let it it. It caused a major problem. been easier through SCEC. work for a while, so I got on out, but he decided that he The coral was so young that it the phone and found out about would give it to me because he made no sense. There are many ways that the a network of private collectors was also curious about how SCEC structure supports this in the area, some of whom had We were very concerned about old it is. kind of work. For example, the published their work. I found this. It prevented us from field trip at the SCEC annual Frank Peska, a collector who publishing our work since we meeting was a vehicle for us to had this internal inconsistency. get a peer review of our work, Hai Cheng spent a lot of time which was very valuable. in the lab and was able to show The key to figuring this out is the that there was contamination SQN—Speaking of of the sample. We think there working together, did you ever multidisciplinary work. The result is much was a mix-up in labeling sit in the same room as an during curation or collection of entire team? greater than the individual contributions. the sample. LG—Roz and Eldon The pieces were so small that a are in consulting. Eldon is group of them was used for working on a Ph.D. on a had a very nice coral from an dating rather than a single different topic. Karl is in area that we really wanted to SQN—Such dating is specimen. Apparently, what Colorado. George is in San date. He had published a paper not an everyday lab technique. happened was that two Diego and does a lot of on other aspects of the site. How did you get that work different kinds got into the paleontological consulting. Kanakoff and Emerson did the done? sample. We were finally able to Larry and Hai are in Minne- benchmark scientific work on prove with the lab work that sota. that fossil locality. After that LG—That’s how there was no geological initial work, the area was Larry Edwards came in. Kerry significance and therefore we graded for development and Sieh intervened on our behalf I have never met Larry could throw them out. Frank Peska collected as that and asked Larry if he’d be Edwards and Hai Cheng. I work was being done. willing to do it for us. He and don’t think that the rest of us Hai Cheng, a post-doc working have all been in the same room He had documented all this. I with Larry, did the dating. SQN—That’s quite a at the same time. That’s been found out about it because of They used high-precision team effort. Did SCEC have a one of the difficulties. Any his write-up for the Natural thorium methods. role other than funding? project where you have so

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many people involved and all can’t stop them? Our response LG—I’m not sure aspects of it. For example, Karl portions are very important, should be based on solid that’s the case. My motivation, is doing a very detailed and the people are spread out, science. my interest is hazard-oriented, structural analysis of the area. there can be some logistical but I think most of what I’ve I was at Caltech working on For now, we want to put difficulties. done is pure science. I think the earthquake geology under together all the pieces of the hazard drives my interest in SQN—Can you Kerry Sieh when I got inter- puzzle and show that bigger the science. Most of my time I describe the interplay between ested in the San Joaquin Hills. I picture to the world. We’ll spend teaching. If I had more your role as scientist, teacher, wanted to know what kind of build on that later. time for research, I might work mother, ordinary citizen, and hazards might affect me, my more directly with hazard- SQN—Do you think oriented work than just pure publishing this work will lead science. to opportunities for public awareness and education? SQN—Are there I hope that when we publish our work, it will be knowledge transfer implica- LG—I would be a reminder that southern California is tions of the technical work pleased if that’s an outcome. It your group is doing on the San would be nice if I could work seismically active and that if you’re a resident, Joaquin Hills? with SCEC’s Outreach Program to make that happen. I see it as it’s something you should be concerned about LG—I think that the a public education opportunity. thorium dating will be helpful and you should support mitigation activities. I think that’s partly just my in evaluating other structures perspective as a professor. in the L.A. basin. Whenever you’re dealing with Quater- your early training as an family, my house—backyard Here in Orange County, the nary structures, dating is very environmental engineer? geology, basically. prevailing attitude is that we important. One of the ways it’s don’t have damaging earth- LG—Being broadly Originally, I studied environ- been done is to date fossils quakes. The last significant trained as an environmental mental engineering at Caltech. using amino acid methods, earthquake here was on the geologist, I have an unusual I had identified a Ph.D. thesis which are very good but not as Newport-Inglewood fault in perspective on earthquakes as topic on the transport of precise. There haven’t been 1933. To most, it’s ancient an environmental problem. My inorganic contaminants very many corals available to history. I hope that when we primary interest is in earth- between a stream and its bed. I calibrate the amino acid dates publish our work, it will be a quake geology. I’m fascinated was working on experiments in in the fossil assemblages. I’ve reminder that southern by the problem of earth- a hydraulics laboratory, quakes—what causes them. collecting data for my Ph.D. candidacy exam. That’s the basic science, but the reason I’m fascinated is that I was minoring in geology . I can’t think of a better infrastructure for con- they affect me. I see earth- because I had long had the quakes as the ultimate environ- twin interests and because I ducting this work than what SCEC provides. mental problem. We can’t like to see environmental control them. I’m fascinated by problems from an earth science the science: what causes perspective. In my first week at earthquakes, where are they graduate school, the Whittier been talking with Dan Ponti, likely to strike, how are they Narrows earthquake hit. I was California is seismically active who has done a lot of this kind likely to affect us. But I also see seduced by the earthquake and that if you’re a resident, of work, to help find some it as an environmental prob- science that was going on. I it’s something you should be calibration that will allow more lem: the interaction between took a class from Kerry Sieh, concerned about and you precision in estimates of uplift people and the physical and I was hooked. should support mitigation rates and deformation rates environment. activities. How many people had died farther north in the L.A. basin. I don’t know of any other from contaminated water in That’s a side story to what we The research we do is ulti- earthquake scientist who was California compared with the were doing in the San Joaquin mately funded by taxpayers. If in labor during the Landers potential for all-out catastrophe Hills, but I think that’s going to they’re not aware of the earthquake. I was vulnerable from an earthquake? It seemed be of value to other research- problem and supportive of our and very frightened. I missed a more important problem to ers. work, we won’t have the the scientific opportunities, but work on. funding for the long term. So I got a powerful experience of All the authors on this current the education aspect is very the human impact of earth- work have other interests in important. That’s why I am quakes. SQN—Does your this project. I suspect that once happy to do this interview. background give more of a we publish our combined How do we respond to hazard focus than other earth work, there will be a sequence earthquakes, given that we scientists? of papers building on different Interviewer: Ed Hensley

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 16 S C E C Southern California Earthquake Center

SCEC News Briefs • SCEC News Briefs

Plans to Make a Lasting Impact Earthquake Fair ANNA-SCEC Partnership Concludes The successful partnership culminated with the ANNA-SCEC Earthquake Prepared- Over the past year, the Los Angeles area Adams-Normandie ness Fair on Saturday, April 18. The fair Neighborhood Association (ANNA) has partnered with the was billed as a “one-stop learning and Southern California Earthquake Center to elevate earthquake shopping center” featuring vendors awareness and preparedness on a communitywide scale. The who displayed their products. The partners developed a model program for seismic safety to create a locally famous “Quake Cottage” culture of sustainable, uniform community preparedness for a gave community members a damaging urban earthquake. The partners believe the model can chance to safely experience a be cost-effectively replicated in vulnerable neighborhoods simulated magnitude 8 earth- anywhere. quake. Food was provided by McDonalds and by a neighbor- Last year, ANNA president Marianne Mullerleille, a resident of hood chef who put his barbecu- the Adams-Normandie neighborhood, submitted a proposal to ANNA President Marianne Mullerleille was a ing skills to the test—explaining the University of Southern California’s Neighborhood Outreach popular figure, especially during the raffles. that this is the ideal way to cook Program. The Outreach Program is a nonprofit corporation with a after an earthquake. Fun and games were provided for the kids mission to enhance the quality of life in the neighborhoods (young and old)—there were clowns, balloon animals, a moon- surrounding USC’s University Park and Health Sciences cam- bounce, and even the “Earthquake Game” at the SCEC exhibit. puses. It was created in 1993 to provide financial support to USC- community partnership projects and programs that make a USC’s School of Letters and Department of Psychology provided visible, positive impact in our neighborhoods. Donations from expertise for the required “objective evaluation.” Dr. Margaret university faculty and staff through the USC Good Neighbors Gatz, professor and practicing clinical psychologist, has com- Campaign are the sole source of USC Neighborhood Outreach pleted extensive research in the funding. field of earthquake prepara- tion. In her work, she examines The ANNA-SCEC Project partners identified several objectives multi-generational predictors addressing the overall education and safety of the community it of earthquake impact and reaches out to. Through the ANNA after-school program, the preparedness. At the beginning project emphasized the improvement of the quality of K-12 of the yearlong program, Dr. education and the quality of life for children who attend neigh- Gatz, with the assistance of borhood schools. The program included a community initiative to graduate student Kecia Watari, improve public safety through natural disaster education and assessed the community’s mitigation strategy planning aids reduction of crime and violence. attitudes toward earthquakes SCEC assisted with projects to improve the neighborhood’s economic development by helping families build preparedness kits, retrofit their homes, and offering low-cost gas shut-off valves The ANNA-SCEC Earthquake Fair emphasized a from the Gas Company. combination of fun and education. Outreach Director Jill Andrews played the Earthquake Game with neighborhood kids. Others took advantage of the face painting and balloon hats. ANNA photos by Jill Andrews & Sara Tekula & Sara Jill Andrews ANNA photos by

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 17

SCEC News Briefs • SCEC News Briefs and measured its reliance on SCEC Shares Its Experience at PEER preparedness and mitigation strategies. Those who com- Education Program Meeting pleted the surveys were given a complementary one-day On May 1, 1998, Pacific Earthquake Engineering Research (PEER) earthquake preparedness kit. hosted a meeting on its Education Program. SCEC’s Outreach Team reported on its education program and activities, especially Results of the study were changes that have taken place at SCEC in the past few months. compiled for future compari- son to a post-test, and were Outreach Director Jill Andrews outlined the current education reported at an ANNA monthly projects, emphasizing the web-based education modules now meeting. A post-test conducted under development. Outreach Specialist Mark Benthien spoke at the completion of the about SCEC’s internship program for undergraduates, and Outreach Specialist Sara Tekula reported on the IRIS Education partnership (immediately after Outreach Specialist Sara Tekula welcomes the fair), measured the same Michael Essing (L) and Rick Smalling, of Safe-T- and Outreach Planning Meeting (see story in this issue). factors in the community. The Proof Disaster Preparedness Company. Their “Quake Cottage” simulates an M 8 earthquake. results are being compiled and The Education Program is directed by Gerry Pardoen (UC Irvine) will be compared to the pre-test. The partnership sparked interest and coordinated by Carrie Lincourt (UC Irvine). The education in future community projects that may examine social applica- subcommittees are chaired by Scott Ashford (K-12), Abe Lynn tions of earthquake-related research. Finally, a community (Undergraduate Interns), Jon Stewart (Undergraduate Scholars), guidebook is under construction by SCEC. The book will be Ronnie Borja (Graduate Fellowships), Kurt McMullin (Continuing mounted on the World Wide Web as a guide to other communi- Education), Gerry Pardoen (Minority/Outreach Programs), and ties. Watch for an announcement about December in SCEC Dave McClean (Affiliates Scholarships and Fellowships). publications list and web site: WWW.SCEC.ORG. Scott Ashford, with SCEC’s former director of education Curt SCEC Presence at TechEd 98 Abdouch as a consultant, addressed how new Education Program could meet the needs of the K-12 community. Scott and Curt On May 4, 1998, SCEC representatives presented Web-based discussed internships for high school students, development of instructional modules to a convention of community college hands-on activities for teachers, links to the Future Scientists and educators. The event was the Community College Foundation’s Engineers of America (FSEA), and a partnership with the Irvine Technology in Education Conference in Santa Clara, California. Unified School District (using UC Irvine as a gateway).

Outreach Specialist Sara Tekula, SCEC Data Center Manager Other topics addressed included PEER’s successful Undergradu- Katrin Hafner (Caltech), and SCEC Web author/developer John ate Internship Program and a commitment to conduct workshops Marquis (Caltech) presented the SCEC education module “Inves- to educate those in business and industry. tigating Earthquakes through Regional Seismicity.” PEER brings together the premier earthquake engineering In the one-hour presentation, Tekula gave an overview of the research universities in the western U.S. to develop technologies SCEC Outreach program. Hafner and Marquis then walked and implementation strategies to reduce the life-safety and attendees through portions of the module, allowing time for economic risks of major earthquakes. Center researchers have questions during the demonstration and at the end of the work- expertise in diverse areas including earthquake hazards, analysis, shop. design, risk and reliability, and economics and policy planning. Hafner, who also teaches at two Los Angeles area community The objectives of PEER’s educational program are to raise the colleges, felt that the module received “positive feedback on its awareness of the effects of earthquakes in urban regions and to usability in the community college setting.” Hafner is the man- stimulate interest in earthquake engineering among students, ager of SCEC’s Data Center at Caltech. The module uses the Data with a special emphasis on underrepresented minorities. Center’s real-time data to create a dynamic learning experience, thus also advertising the many types of data presentations PEER programs include a public education program for teachers available on the Data Center’s Web pages (WWW.SCECDC.SCEC.ORG). and students as well as the general public; an undergraduate Hafner noticed that “people are really excited about real-time data summer intern program to attract and retain earthquake engineer- and how it can tie into education.” ing undergraduates; the Earthquake Engineering Undergraduate The SCEC Outreach Program has formally named Scholars Course; Earthquake Engineering Graduate Fellowship its Web-based education project Program to recruit and support excellent Ph.D. students; and continuing professional education courses. DESC Online For more information about the PEER Education Program, email Development of Earth Science Curricula Online Carrie Lincourt at [email protected], or visit the PEER web site: HTTP://PEER.BERKELEY.EDU/.

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 18 S C E C Southern California Earthquake Center

SCEC News Briefs • SCEC News Briefs

SCEC Represented at National Science The course was limited to local government reviewers of the seismic hazard reports mandated by the Seismic Hazards Map- Teachers Association Convention ping Act. Dr. Ray Seed, course organizer and head of the Civil and Environmental Engineering Group at UC Berkeley, said the course Las Vegas, a city well known for lively entertainment, became a was “designed to present a concise but practical discussion of city filled with lively science teachers between April 16 and 19. alternative approaches and controversial topics related to hazard The Las Vegas Hilton and the Las Vegas Convention Center evaluation and mitigation.” served as headquarters for the 46th Annual National Conference of the National Science Teachers Association. On the first day, speakers covered the selection and use of strong motion data, including an overview of the Statewide Probabilistic SCEC Outreach Education Specialist Sara Tekula joined thousands Ground Motion maps, along with seismic/dynamic soil proper- of educators at the convention, where seminars, workshops, and ties and their evaluation. The second and third days were devoted exhibits helped bring attendees up to date on course content, to the evaluation and mitigation of soil liquefaction hazard and teaching techniques, and new technology applications. A primary seismic slope instability and deformation, respectively. function is simply to give them a chance to network with others who focus on the same area of interest. More such courses for consultants and geotechnical practitioners are planned. To find out more about them, contact the UC According to Sara, the convention was a “great chance for Berkeley Geotechnical Engineering Program at (510) 642-1262. teachers from all over the country to share ideas and experiences within their domains of expertise.” She spoke with many earth

SCEC-USGS Workshop on LARSE II On April 21 a science seminar, sponsored by SCEC and the USGS,

Photo: Sara Tekula Sara Photo: was held at UCLA. The goals of the meeting were to review the current state of knowledge on the deep structure of the Los Angeles Region, determine how previous phases of LARSE (Los Angeles Region Seismic Experiment) have contributed to this knowledge, and identify how the next phases will contribute more data for study. Over 60 scientists attended the meeting organized by Paul Davis (UCLA), Gary Fuis (USGS), and Rob Clayton (Caltech). A total of 18 presentations were given. The morning focused on the Santa Monica area, which received higher than expected damage during the Northridge earthquake (1994) compared to other areas at the same distance from the epicenter. Several overview presentations were given as an introduction to the area, including evolution at Pictured here are teachers during an earth science workshop at the NSTA Convention. In this session, the edge of the Transverse Range rotation, and more recent the teachers were able literally to play with (i.e., learn about) dirt. seismicity and structure along the Santa Monica fault. science teachers about the integration of earthquake science into Several theories were then presented as to the cause of the curricula and heard suggestions on how to make the SCEC web- damage, including a possible deep structure related to the based science education modules (currently under development) southern Santa Monica fault, which acted as a “lens” to focus more user-friendly. Sara attended two Earth Science Share-A- seismic energy in the damaged region. Other studies were Thons, where teachers demonstrated successful methods to presented that argued that the strong shaking could have resulted actively engage science students through hands-on activities. by focusing much nearer to the surface related to the northern Santa Monica fault. Seismic Hazard Evaluation and The LARSE II experiment is designed to resolve the controversy. It is expected that results of the Santa Monica study will be appli- Mitigation Short Course cable to other areas where seismic energy can be focused to cause unusual damage. A short course for geotechnical professionals on evaluation and mitigation of seismic hazards associated with slope instability and The afternoon was devoted to the broader goals of LARSE II. As soil liquefaction was held in Los Angeles in January. The Califor- in the morning session, several overview presentations were nia Division of Mines and Geology, in partnership with SCEC and given detailing the evolution, structure, and seismicity of the area UC Berkeley’s Department of Civil and Environmental Engineer- to be studied. Results from Northridge earthquake studies and ing, sponsored the event. LARSE I were presented to show what is already known.

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 19

Also Of Interest . . .

IRIS News recognize earth science as a formal category of study. Issues of IRIS Plans New E&O Program scale, span, and context of projects were overarching concerns. After ideas were compiled and presented, the group broke up About two years ago, the Incorporated Research Institutions for again and wrote the first drafts of a formal plan addressing (1) Seismology (IRIS) Consortium created its Education and Outreach rationale, scope, and purpose; (2) objectives and plan; (3) relations Program, aiming at improving seismology and related earth with other science education and national programs; and (4) science education in K-12 schools, colleges, universities, and adult evaluation and assessment. education. IRIS’s E&O Program has the potential to reach the entire nation through its 91 member institutions. Although still in the planning stages, the program has achieved a sense of direction through this workshop. For more information, To create a framework for the program, IRIS formed the Educa- please refer to the IRIS web site: WWW.IRIS.EDU. The SCEC Commu- tion and Outreach Committee and named Catherine Johnson nity would like to extend best wishes and offers the hand of (formerly of Scripps Oceanographic Institute) E&O program partnership to this effort. manager. Members of the committee include Karen Fischer (Brown), Glenn Kroeger (Trinity University), Guust Nolet USGS News (Princeton), Michelle Hall-Wallace (Arizona), Jeff Barker (SUNY Group to Reevaluate SF for Quakes Binghamton), Bob Hutt (USGS-ASL), and Larry Braile, Chair (Purdue). These and other experts in education attended the IRIS The USGS at Menlo Park is beginning Working Group 99, a E&O planning workshop in April in Warrenton, VA. reevaluation of Bay Area earthquake probabilities. The group’s report will be issued in October 1999—the tenth anniversary of The workshop opened with a presentation on the background of the Loma Prieta earthquake. There will be working groups on the IRIS E&O Program, and selected attendees gave brief presen- source characterization, moment budget/background earth- tations on their education programs at their organizations and quakes, time dependence, and calculations. Tom Henyey, SCEC’s institutions. SCEC Outreach Education Specialist Sara Tekula center director, will represent southern California in this effort. spoke on behalf of SCEC’s Outreach Program and made recom- mendations to the IRIS committee. These presentations, high- FEMA News lighted by contributions from Robert Ridky, Mike Mayhew, Leonard Johnson, Trish Morse, and Nora Sabelli, all of the NSF, Earthquake Protection Grant for added insight on planning for and focusing its efforts. Southern California Schools Approved The large group (approximately 30 people) broke up into smaller FEMA recently announced that it will provide more than $10.7 brainstorming groups, using what had been presented as a guide million for school mitigation projects to protect children and to outline the most significant tools IRIS can use to make a lasting reduce damage from future earthquakes in southern California. impact on seismology and earth science education. Addressing The funds, allocated from the FEMA Hazard Mitigation Grant IRIS’s strengths and capabilities, the group documented a list of Program, are targeted to seismically retrofit and strengthen public possible endeavors in the areas of teacher preparation and and private facilities qualifying for the program. To date a total of professional development, data accessibility, internship programs, more than $360 million in federal disaster money has been development of web materials, and the support of the National approved for earthquake preparedness projects throughout Science Education Standards. For the first time, the standards southern California as a result of the 1994 Northridge earthquake. The serene Airlie Resort was the host site for the IRIS education and outreach workshop. The FEMA mitigation grant program provides 75-percent funding to state and local entities for cost-effective projects that help to make communities safer from future disasters. More information is available on the FEMA Web site: WWW.FEMA.GOV. New Name, New Logo NCEER Is Now MCEER

MCEER (formerly NCEER) recently unveiled its new logo, reflecting both the nature of its work and the

Photo: Sara Tekula Sara Photo: fact that it is no longer the only national center for the support of earthquake engineering.

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 20 S C E C Southern California Earthquake Center

Eight Undergraduate Scholars Chosen for SCEC Summer

nternship Program Coordinator Mark Benthien recently am looking forward to the opportunity to improve my under- announced the newly selected participants for the SCEC standing of geology and experience in research with this project. I ISummer Internship Program, now entering its fifth year. We enjoy independent study and application of my undergraduate highlight here the students, their research mentors, project titles, training. Furthermore, this project encompasses a field of study and personal goals. Unless otherwise noted, the mentor and I’m interested in—structural geology. Thus, my personal goal is to student are at the same institution. learn as much about geology as I can and contribute to science and education.” Safaa Dergham, geology major at California State University Long Beach Jacqueline Moccand, environmental will be working with Sally McGill, CSU studies major at USC, will be working San Bernardino. The name of Safaa’s with Ann Blythe. The name of project is “Paleoseismic Studies of the San Jacqueline’s project is “Geomorphic Andreas Fault in the San Bernardino Mapping and 3-He Chronology of Rock Area.” Safaa writes, “My plan is to get a Slide Scarps along the Oak Ridge Fault.” masters degree in geology with a geo- Jacqueline applied for the internship “to physical and seismological emphasis. gain hands-on experience in the field of Once I receive my degree, I would like to geology, especially to gain a greater get a job that allows me to apply and knowledge in the area of seismology and expand my knowledge in the field, and geochronology, both of which I am most get some real-life practice. However, my interested in. I believe the experience of a ultimate and eventual goal is to get a Ph.D. in seismology and SCEC internship will make me a better find cheaper ways to study and predict earthquakes and their scientist and give me a greater understanding of how the system behavior.” works and what is required in the research arena—not to mention make me more marketable for a future job linked to geology.” Leland Green, geological sciences major at UC Santa Barbara, will be working with Tracy Pattelena, geophysics major at Craig Nicholson. The name of Leland’s Pasadena City College, will be working project is “Development of an Interface with David Okaya and Nikki Godfrey of for 3-D Visualization of SCEC Earthquake USC. The name of Tracy’s project is Data on the World Wide Web.” Leland “Velocity Structure in the Los Angeles writes, “I have realized over the past few Basin from Tomographic Inversion of years that in order to succeed, I must Active Source Data.” Tracy writes, “My develop a variety of skills. Keeping this in academic goals are to obtain my BS in mind, I have tried to learn skills that are geophysics from UC Santa Barbara and outside the field of geology but still have then to proceed to graduate school, relevance to geology. This project will possibly at USC or Caltech. My career allow me to apply the skills that I learned goal is to do what I love—study earth- in Java programming class last quarter to my field of study. It will quakes, ground motion, perhaps even also give me a chance to learn more about seismology and the volcanoes. My ideal job title would be Research Geophysicist. My ways in which information can be presented to educate others personal goal is to contribute to geology through research, about geologic processes. Eventually I would like to become a discovering what we don’t yet know and further investigating professor. This project will be an important part of achieving this what we think we do know, assessing hazards and monitoring goal because it will show my ability to use what I have learned to potential dangers, to keep the public informed. It is my true educate others. It will also increase my knowledge of computer passion for this science that drives me.” applications used in geology and ways in which these applica- Justin Rubinstein, applied geophysics tions can be used for education.” major at UCLA, will be working with Lowell Kessel, geological sciences major Paul Davis. The title of Justin’s project at UC Santa Barbara, will be working is “A Study of the Azimuthal Depen- with Arthur Sylvester. The name of dence of Seismic Focusing Experienced Lowell’s project is “Folding and Faulting within Sherman Oaks.” Justin writes, along the San Andreas Fault, Palmdale, “Through this project I hope to create a California: Implications for Simple Shear stronger understanding of geophysical Mechanics and Education of the Public.” research methods, as well as better my Lowell writes, “My goal is to contribute research skills. Professionally, I intend to science and public education and my to pursue a Ph.D. in geophysics. I am own curiosity by describing the geology, interested specifically in seismology. structure, and tectonic evolution of the Upon completion of my degree, I hope fault zone within the Palmdale area. I to find a job in the southern California

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 21

Internship Program Research Program and Funding area, preferably a job in academia. I then plan to continue research 1998 SCEC Research Projects involving seismic hazards and the possibility of dependable by John McRaney seismic prediction.” he SCEC board has completed its review of proposals Javier Santillan, geological sciences submitted in response to the 1998 RFP. A list of research major at UC Santa Barbara, will be projects supported by SCEC in 1998 is shown at the end of working with Jaime Steidl. The name of T this article. SCEC received 150 proposals requesting more than Javier’s project is “Understanding $7.8M. Most were from scientists long involved with SCEC. SCEC Ground Motion Variations at the Van has $4.29M in funding for 1998 ($400K less than 1997)—$3.04M Norman Dam Complex Site.” Javier from NSF, $1.0M from the USGS, and $250K from Caltrans. writes, “My personal goal is to become proficient in the research process. I have SCEC’s Scientific Mission learned that academic research is very difficult and is a skill that must be The center’s research objectives are to develop and improve the continually refined. Undertaking this scientific basis of earthquake hazard estimation. The primary project will allow me to learn many emphases are (1) earthquake potential, or the probability of research skills, most notably the use and earthquake occurrence as a function of location, magnitude, and care of seismic data collection instruments as well as the use of the time; (2) rupture dynamics; and (3) ground motion, or complete UNIX operating system for data analysis software. My ultimate theoretical seismograms for any earthquake at any site. academic goal is to earn a Ph.D. in the geological sciences. I plan Earthquake potential studies include studies to identify active to attend graduate school in the fall of 1999. I am very interested faults and to estimate their maximum magnitudes and slip rates; in structural geology and metamorphic petrology. I believe this geodetic studies to measure regional and local strain rates; project will help me to better understand the research process and seismicity observations and focal mechanism studies; theoretical broaden my knowledge in the geological sciences. My career studies that relate earthquake potential to tectonic setting and goals at present are varied. After completing a Ph.D., I plan to observable quantities; and hypothesis testing. apply for a research position with the petroleum industry or perhaps even do some work with an academic research unit. I am Rupture dynamics research includes theoretical and numerical even interested in teaching geology at some point.” studies of rupture initiation, propagation, and arrest. It includes studies of energy flux, interaction with pre-stress and dynamic stresses, and the stress changes resulting from rupture. Rupture Lisa Sarma, civil engineering major at dynamics also includes observation and interpretation of rupture Columbia University School of Engineer- propagation using seismic, geologic, and geodetic data. ing and Applied Science, will be working Ground motion studies have the objective of predicting the full with Thomas Heaton at Caltech. Lisa’s theoretical seismograms (“time histories”) for any combination of project is “Investigation of the Coupling earthquake and site. Our objective is to explain the relevant between Structures and Ground Vibra- seismic records for past earthquakes, and develop a capability for tions and the Implications on Damping in predicting ground motions from hypothetical future earthquakes. Buildings.” Lisa writes, “I want to apply Ground motion calculations should account for complexities in my knowledge of geophones and geo- rupture dynamics, wave propagation, and nonlinear site effects. physics and make a contribution to In its research plans for 1998, SCEC will emphasize the interdisci- something useful. I like the idea of getting

Intern photos: Mark Benthien Intern photos: plinary tasks described below. hands-on exposure to the actual applica- tions and use of the subjects that I have Seismic Hazard Estimation studied in class. As a future civil engineer, I plan to develop and use environmentally sensitive building techniques and, in doing The Phase III report (to be completed this year) will describe a so, increase others’ awareness of the importance of conserving the suite of seismic source models for southern California, examine balance between humans and our habitat. I am currently majoring models for local site effects, describe the effect of 3-D wave in civil engineering and minoring in earth and environmental propagation in sedimentary basins, show representative seismo- engineering. I hope to acquire as much knowledge as I can about grams for scenario earthquakes, and discuss uncertainties and both engineering and the environment to make the most positive sensitivity to assumptions in seismic hazard estimation. In impact in my work. I intend to pursue a master’s degree immedi- addition, the report will present several data bases, including an ately after I finish my undergraduate education to deepen my earthquake catalog, fault slip rate table, soil map, and theoretical understanding of engineering and to concentrate on my areas of seismograms. interest. These include green building, responsible design, and sustainable development. Following my graduate work, I intend 3-D Seismic Velocity Model to start a company where I will apply civil engineering to the Calculation of complete seismograms requires a model to evaluate mutual benefit of humankind and the environment.” P and S velocities at any point in the medium through which

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 22 S C E C Southern California Earthquake Center seismic waves propagate. Rob Clayton of Caltech will organize an the horizontal crustal deformation map determined from geodetic interdisciplinary project to construct a standard seismic velocity observations, provide relevant constraints for models of stress model that satisfies a range of geophysical and geological evolution. Research on this subject may include calculation of observations, including strong motion seismograms, earthquake time-dependent stresses, comparison of earthquake occurrence travel times, and borehole geologic data. The model will include (including aftershocks) with the local stress field, and testing of the effects of sedimentary basins and near-surface sediments. The hypotheses following from the models. model will be used to calculate theoretical seismograms and stress increments from earthquakes and tectonic motions. Theoretical studies may involve construction of theoretical models of stress evolution and adjusting parameters for agree- ment with geologic, geodetic, and seismic data. Observational Stress Evolution studies may involve in-situ stress measurements; geological Earthquakes result from stress release on faults, and one desired measurements of displacement patterns in past earthquakes; feature of the Master Model is a facility for calculating the stress geodetic measurements of strain rate to reveal stress interactions; accumulation from past earthquakes, tectonics, and viscoelastic and measurements of earthquake locations, focal mechanisms, stress relaxation. Recent SCEC products, including a catalog of and other observables revealing the relationship between stress earthquake focal mechanisms for M 6 earthquakes since 1850 and and earthquakes.

Southern California Earthquake Center 1998 Funded Projects

Principal Investigator Affiliation Group Project

Mark Abinante & Leon Knopoff ...... UCLA ...... G ...... Model of Dynamic Fractures in a Continuum Duncan Agnew ...... UC-San Diego ...... E ...... Estimating the Velocity and Strain Field in Southern California Using Gridded Splines Duncan Agnew ...... UC-San Diego ...... E ...... Fault-Zone Interaction: A Study of the San Jacinto Fault John Anderson ...... Nevada-Reno ...... B ...... High Frequency Ground Motion by Regression and Simulation Jill Andrews ...... USC ...... I ...... SCEC Education and Knowledge Transfer Program Ralph Archuleta ...... UC-Santa Barbara ...... I ...... Portable Broadband Instrumentation Ralph Archuleta and Alexei Tumarkin ...... UC-Santa Barbara ...... I ...... SCEC Strong-Motion Database SMDB and Empirical Green’s Functions Library EGFL Ramon Arrowsmith and Lisa Grant ...... Arizona State ...... C ...... Historic and Paleoseismic Behavior of the South-Central San Andreas Fault Between Cholame and the Carrizo Plain—Cont Yehuda Ben-Zion ...... USC ...... G ...... Coupled Self-Organization of Seismicity Patterns and Networks of Faults, and Basis for Evaluating Seismic Risk and Precursors Yehuda Ben-Zion ...... USC ...... D ...... High Resolution Imaging of Fault Zone Properties Yehuda Bock ...... UC-San Diego ...... E ...... Infrastructure Support for Southern California Integrated GPS Network (SCIGN)/Permanent GPS Geodetic Array (PGGA) James Brune ...... Nevada-Reno ...... B ...... Study of the Topping Accelerations of Precarious Rocks in a Profile Perpendicular to the San Andreas Fault for Constraining Strong Motion Attenuation Relationships for Great Earthquakes Robert Clayton ...... Caltech ...... B/D ...... Using Reciprocal Green’s Functions to Model Strong Ground Motion Robert Clayton ...... Caltech ...... D ...... Real Time Back-Projection of Seismic Array Data Robert Clayton ...... Caltech ...... I ...... SCEC Data Center Operation Paul Davis ...... UCLA ...... D ...... Management of LARSE II (UCLA) Stress Modeling and Data Analysis Paul Davis ...... UCLA ...... D ...... LARSE II: High Resolution Santa Monica Experiment Paul Davis ...... UCLA ...... B ...... Analysis of Northridge Aftershock Amplitudes and Damage and Santa Monica High Resolution Experiment Steve Day and Ruth Harris ...... San Diego State ...... G ...... Dynamic Modeling of Earthquakes on Inhomogeneous Faults Steve Day ...... San Diego State ...... B ...... Effects of Low Velocity Near-Surface Sediments on Long Period Basin Response Steve Day and Jeffry Stevens ...... San Diego State ...... B ...... Three-Dimensional Simulation of Long Period Ground Motion in L.A. Basin James Dolan ...... USC ...... C ...... Identification of Potential Paleoseismologic Trench Sites on the San Andreas Fault Between Palmdale and Gorman James Dolan ...... USC ...... C ...... Paleoseismologic and Slip Rate Study of the Raymond Fault Danan Dong ...... JPL ...... E ...... Optimal Separation of Coseismic and Postseismic Deformations from Secular Tectonic Motion Ned Field ...... USC ...... A/B ...... Phase III Summary, PHSA Source Model, and Ground Motion Simulation Comparisons Bill Foxall ...... LLNL ...... A ...... Epistemic Uncertainty in Geologic Source Chacterization for Probabilistc Seismic Hazard Analysis Nikki Godfrey, David Okaya, Tom Henyey ...... USC ...... D ...... 3-D Contribution from LARSE 1 Data to the SCEC 3-D Velocity Model Lisa Grant ...... Chapman ...... C/A ...... Neotectonics and Holocene Paleoseismology of the San Joaquin Hills Rob Graves, Arben Pitarka, Dave Wald ...... Woodward-Clyde/USGS... B/D ...... Ground Motion Validation Studies on the Southern California 3D Velocity Model

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 23

Rob Graves ...... Woodward-Clyde ...... B/D ...... Setup of 3D Velocity Model: Version 1 Katrin Hafner, John Marqui, Egill Hauksson ...... Caltech ...... E ...... Earthquake-Related SCEC Educational Modules for the WWW Brad Hager ...... MIT ...... E ...... Continuum Mechanics Models of Blind Thrusts in the LA Basin Jeanne Hardebeck, Jishu Deng, Egill Hauksson .. Caltech ...... A ...... Tectonic Stress and Earthquake Hazards Egill Hauksson ...... Caltech ...... D ...... 3-D Velocity Models and Focal Mechanisms Don Helmberger ...... Caltech ...... B ...... Basin-Edge Structures from Waveform Modeling Tom Henyey, Paul Davis, Rob Clayton ...... USC ...... D ...... LARSE II Tom Henyey ...... USC ...... I ...... 1998 SCEC Management Operations Tom Henyey ...... USC ...... I ...... 1998 SCEC Visitors Program Tom Henyey ...... USC ...... I ...... 1998 SCEC Workshops Tom Herring ...... MIT ...... E ...... Geodetic Constraints on Interseismic, Coseismic, and Postseismic Deformation in Southern California Gene Humphreys ...... Oregon ...... A ...... Fully 3-D Visco-Elastic Faulting Response Dave Jackson ...... UCLA ...... I ...... Management and Public Relations Dave Jackson, Yan Kagan, Z. Shen, L. Sung ...... UCLA ...... A ...... Seismic Hazard Estimation Hadley Johnson ...... UC-San Diego ...... E ...... Geodesy Infrastructure: GPS Data Archiving Yan Kagan, Dave Jackson, and Z. Shen ...... UCLA ...... A ...... Stress Modeling Hiroo Kanamori ...... Caltech ...... D ...... Determination of the Slip Plane of Mid-Crustal Earthquakes in Southern California Hiroo Kanamori & Egill Hauksson ...... Caltech ...... I ...... Enhancement of TERRAscope Ed Keller ...... UC-Santa Barbara ...... C ...... Earthquake Hazard of the Santa Barbara Fold Belt, Santa Barbara, California Keith Kelson & John Baldwin ...... William Lettis & Assoc .... C ...... Paleoseismic Investigation of the Northridge Hills Fault, Northridge Park Robert King ...... MIT ...... E ...... Support for GPS Analysis Leon Knopoff ...... UCLA ...... G ...... Model of the Southern California Fault Network Leon Knopoff ...... UCLA ...... G ...... Nucleation and Breakout of Large Earthquakes Monica Kohler ...... UCLA ...... D ...... I. Subsurface Imaging of Lithospheric Structures Using Dense Array Data. II. Site Preparation for the Los Angeles Region Seismic Experiment. II Passive Phase Scott Lindvall ...... William Lettis & Assoc .... C ...... Paleoseismic Study of the San Andreas Fault at Frazier Mountain Bruce Luyendyk ...... UC-Santa Barbara ...... A ...... SCEC Standing Committee on Electronic Communication Mini-Workshop: Cataloging and Archiving Information in a Digital Library Harold Magistrale ...... San Diego State ...... B/D ...... 3D Seismic Velocity Models of Populated Southern California Basins Harold Magistrale ...... San Diego State ...... D ...... Integrated Los Angeles Area Velocity Model Harold Magistrale ...... San Diego State ...... D ...... Setup of 3-D Velocity Model Version 1 Mehrdad Mahdyiar ...... VortexRock Consultants .. A ...... Probabilistic Seismic Hazard Analysis of Southern California Sally McGill ...... Cal State San Bernardino . C ...... Paleoseismic Studies of the San Andreas Fault in the San Bernardino Area Bernard Minster ...... UC-San Diego ...... A ...... Use of Evolutionary Strategies in Seismicity Pattern Analysis Karl Mueller ...... Colorado ...... C ...... Determining the Geometry of the San Joaquin Hills Blind Thrust: Implications for Earthquake Source Characteristics Karl Mueller ...... Colorado ...... C ...... Structural Analysis of Active Blind Thrusts and Folds in East Los Angeles Kim Olsen ...... UC-Santa Barbara ...... A/B ...... Ground Motion Modeling in Los Angeles Kim Olsen ...... UC-Santa Barbara ...... G ...... 3-D Elastic Finite-Difference Simulation of a Dynamic Rupture James Rice ...... Harvard...... G ...... Elastodynamic Simulations of Rupture Propagation and Earthquake Sequences along Complex Fault Systems James Rice ...... Harvard...... G ...... New Methodology in Computational Seismology for Dynamic Rupture along Complex Fault Systems Tom Rockwell ...... San Diego State ...... C ...... Paleoseismic Study of the San Andreas Fault at Frazier Mountain Charlie Rubin ...... Central Washington Univ. C ...... Hydraulic Trench Shoring for Paleoseismic Studies in Southern California Charlie Sammis ...... USC ...... G ...... Fault Zone Physics Nano Seeber and John Armbruster ...... Columbia ...... A/D ...... Earthquakes, Faults and Stress in Southern California John Shaw ...... Harvard...... D/B ...... Velocity Structure of the L.A. Basin from Sonic Logs and Stacking Velocities Peter Shearer ...... UC-San Diego ...... D ...... Precision Relocation of Los Angeles Region Seismicity Zheng-Kang Shen and L. Sung ...... UCLA ...... E ...... Crustal Deformation Velocity Map Kerry Sieh and Egill Hauksson ...... Caltech ...... C/D ...... Relationship of Aftershocks to Mainshock Rupture of the Landers Earthquake Kerry Sieh ...... Cal Tech ...... C ...... Characterization of Active Faults in East Los Angles Kerry Sieh ...... Cal Tech ...... C ...... Characterizing Seismogenic Sources Associated with the Uplift of the San Bernardino Mountains Kerry Sieh and Doug Yule ...... Caltech ...... C ...... Neotectonic and Paleoseismic Investigation of the San Andreas Fault System, San Gorgonio Pass Jamie Steidl and Ralph Archuleta ...... UC-Santa Barbara ...... B ...... SCEC Borehole Instrumentation Initiative Jamie Steidl ...... UC-Santa Barbara ...... A/B ...... Site Response: Completion of Phase III and Beyond Ross Stein and Dave Jackson ...... USGS/UCLA ...... I ...... SCEC/USGS Workshop on Stress Transfer L. Sung and Dave Jackson ...... UCLA ...... E ...... Regional GPS Surveys Lynn Sykes and Jishu Deng ...... Columbia ...... A ...... Development of a Physical Model of Stresses in Southern California Alexei Tumarkin and Ralph Archuleta ...... UC-Santa Barbara ...... B ...... Integrated Approach to Time Histories Prediction Mladen Vucetic ...... UCLA ...... B ...... Utilization of the Low-frequency Bedrock Motions Calculated by 3-D Linear Methods in the 1-D Nonlinear SCEC SITE-EFFECTS GIS Steve Ward ...... UC-Santa Cruz ...... A/E ...... Research toward the Master Model Ray Weldon ...... Oregon ...... C ...... Analysis of San Andreas Fault Paleoseismic Events at Wrightwood, California Frank Wyatt and Duncan Agnew ...... UC-San Diego ...... E ...... Pinon Flat Observatory: Continuous Monitoring of Crustal Deformation Yue-Hua Zeng and John Anderson ...... Nevada-Reno ...... B ...... Simulation of Ground Motion in the Los Angeles Basin

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 24 S C E C Southern California Earthquake Center SCEC Research Publications & Abstracts

The following is a list of recent updates to the SCEC database of publications based on SCEC-funded research. SCEC authors must obtain a SCEC contribu- tion number to acknowledge SCEC funding, and in return the paper is added to the SCEC Publication Database. This database is reported to the NSF during each SCEC evaluation. To receive a SCEC contribution number for a recently submitted paper (or for a published paper that did not originally receive a SCEC number), email Mark Benthien ([email protected]) with the authors, title, publication name, abstract (very important), and any other bibliographic information. The SCEC number will be returned via email along with the proper NSF/USGS/SCEC acknowledgment statement. The SCEC Quarterly Newsletter now publishes the references only for published articles, no longer listing ones that are submitted, in review, or in press.

207. Abercrombie, R. E., Near Surface Attenuation and Site Effects from of combining space and terrestrial geodetic data to obtain the Comparison of Surface and Deep Borehole Recordings, Bulletin of deformation field in southern California. the Seismological Society of America, 87, pp. 731–744, 1997. 366. Souter, B. J., and B. H. Hager, Faults propagation fold growth 209. Abercrombie, R. E., The Magnitude-Frequency Distribution of during the 1994 Northridge, California, earthquake, Journal of Earthquakes Recorded with Deep Seismometers at Cajon Pass, Geophysical Research, 102, pp. 11931–11942, 1997. Southern California, Tectonophysics, 261, pp. 1–7, 1996. Geological models of buried thrust faults indicate that fault 266. Dolan, J., K. Sieh, T. Rockwell, P. Guptill, and G. Miller, Active propagation folds (FPF) form and grow with a geometry that Tectonics, Paleoseismology and Seismic Hazards of the Hollywood depends on that of the fault (Suppe, 1985; Suppe and Mendeweff, Fault, Northern Los Angeles Basin, California, Geological Society of 1990). The displacement gradient fields for faults and kink folds America Bulletin, 109, pp. 1595–1616, 1997. are very similar, and both can be modeled using dislocations. In this paper we test a geological model of the FPF associated with Data from geotechnical boreholes and trenches, in combination the January 17, 1994, Northridge, California, earthquake to with geomorphologic mapping, indicate that the Hollywood fault determine whether folding along axial planes inferred from is an oblique, reverse-left-lateral fault that has experienced at least geologic models accounts in part for the coseismic surface one surface-rupturing earthquake during latest Pleistocene to mid- displacements measured with Global Positioning System (GPS). or late Holocene time. Geomorphologic observations show that the We test for coseismic deformation on both the main rupture plane fault extends for 14 km along the southern edge of the eastern and active axial planes of related folds by inverting for the Santa Monica Mountains, from the Los Angeles River westward displacements on dislocation planes in an elastic half-space. A through downtown Hollywood to northwestern Beverly Hills, model incorporating two axial planes is preferred to a model with where the locus of active deformation steps 1.2 km southward a single rupture plane in a normalized root mean square (NRMS) along the West Beverly Hills lineament to the Santa Monica fault. sense; however, the distribution of axial plane displacements does Rupture of the entire Hollywood fault, by itself, could produce a not correlate with the displacements on the main rupture plane in M ~6.6 earthquake, similar in size to the highly destructive, 1994 w the way expected for a fault propagation fold. Our results indicate Northridge earthquake, but even closer to more densely urbanized that the deformation associated with folding is too distributed to areas. Assuming a 0.35 mm/yr minimum fault slip rate consistent be resolved on a discrete plane, that the deformation occurs with available geologic data, we calculate an average maximum interseismically, or that one or both of the kink bands does not recurrence interval for such moderate events of *~4,000 years. exist. A model of a single elevated plane, which is parallel to, but Although occurrence of such moderate events is consistent with not coplanar with, the aftershocks, is better in a NRMS sense than the elapsed time since the poorly constrained age of the most the FPF model, indicating that anelastic deformation in the recent surface rupture, the data do not preclude a longer quiescent hanging wall may be distributed. interval suggestive of larger earthquakes. If earthquakes much

larger than Mw ~6.6 have occurred in the past, we speculate that 374. Day, S. M., G. Yu, and D. J. Wald, Dynamic Stress Changes During they may have been generated by the Hollywood fault together Earthquake Rupture, Bulletin of the Seismological Society of America, with other faults in the Transverse Ranges Southern Boundary 88, pp. 512–522, 1997. fault system. We assess two competing dynamic interpretations which have 318. Ni, S.-D., R. Siddharthan and J. G. Anderson, Characteristics of been proposed for the short slip durations characteristic of Nonlinear Response of Deep Saturated Soil Deposits, Bulletin of the kinematic earthquake models derived by inversion of earthquake Seismological Society of America, 87, pp. 342–355, 1997. waveform and geodetic data. The first interpretation would require a fault constitutive relationship in which rapid dynamic 356. Dong, D., T. A. Herring, and R. W. King, Estimating regional restrengthening of the fault surface occurs after passage of the deformation from a combination of space and terrestrial geodetic rupture front, a hypothesized mechanical behavior which has been data, Journal of Geodesy, 72, pp. 200–214, 1998. referred to as “self-healing”. The second interpretation would An approach of efficiently combining various types of geodetic require sufficient spatial heterogeneity of stress drop to permit data to estimate a crustal deformation field is discussed. Three- rapid equilibration of elastic stresses with the residual dynamic step analysis procedures, quasi-observations and general friction level, a condition we refer to as “geometrical constraint.” constraints (“soft” constraints) are employed to ensure both rigor These interpretations imply contrasting predictions for the time and efficiency of the combination solution. The corresponding dependence of the fault-plane shear stresses. statistical tests for checking the compatibility between different We compare these predictions with dynamic shear stress changes data sets and for calculating normalized root-mean-square (nrms) for the 1992 Landers (M 7.3), 1994 Northridge (M6.7), and 1995 are developed and addressed. An empirical non-integer degree of Kobe (M6.9) earthquakes. Stress changes are computed from freedom is defined to handle the case of general constraint and kinematic slip models of these earthquakes, using a finite stochastic perturbation in parameter space, and the increment of difference method. For each event, static stress drop is highly “weighted sum of squared residuals” is defined in the form of variable spatially, with high stress drop patches embedded in a Kalman filtering. With these developments, we show an example background of low, and largely negative, stress drop. The time histories of stress change show predominantly monotonic stress

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 25

change after passage of the rupture front, settling to a residual 3634 Kobe aftershocks and local microearthquakes recorded by level, without significant evidence for dynamic restrengthening. both permanent seismic networks and portable stations that were set up following the Kobe mainshock. Significant velocity The stress change at the rupture front is usually gradual rather variations of up to 6% are revealed in the aftershock area. We than abrupt, probably reflecting the limited resolution inherent in found that areas with high aftershock activity are generally the underlying kinematic inversions. On the basis of this analysis, associated with low Poisson’s ratio, which may be the strong and as well as recent similar results obtained independently for the competent parts of the fault zone and were apt to generate Kobe and Morgan Hill earthquakes, we conclude that, at the aftershocks. The Kobe mainshock hypocenter is located in a present time, the self-healing hypothesis is unnecessary to explain distinctive zone characterized by low P and S wave velocities and earthquake kinematics. a high Poisson’s ratio. This anomaly exists in the depth range of 16 377. Ryberg, T., and Fuis, G. S., The San Gabriel Mountains bright to 21 km, and extends 15 to 20 km laterally. This anomaly may be reflective zone: possible evidence of young mid-crustal thrust due to a fluid-filled, fractured rock matrix that contributed to the faulting in southern California, Tectonics, 286, pp. 31–46, 1998. initiation of the Kobe earthquake. Our interpretation has been supported by many pieces of evidence from hydrological, During the Los Angeles Region Seismic Experiment (LARSE), a geochemical, seismological and geophysical investigations reflection/refraction survey was conducted along a line extending conducted at the Kobe earthquake region. northeastward from Seal Beach, CA, to the Mojave Desert, crossing the Los Angeles basin and San Gabriel Mountains. Shots and 399. Donnellan, A., and F.H. Webb, Geodetic observations of the M 5.1 receivers were spaced most densely through the San Gabriel January 29, 1994 Northridge aftershock, Geophysical Research Mountains to obtain a combined reflection/refraction image of the Letters, 25, pp. 667–670, 1998. crust in that area. A stack of common-midpoint (CMP) data reveals 437. Zhao, D., Seeking the cause of earthquakes, Science Spectra, 11, pp. a bright reflective zone, 1-s thick, that dominates the stack and 6–10, 1998. extends throughout most of the mid-crust of the San Gabriel Mountains. The top of this zone ranges in depth from 6 s (~18-km High-resolution seismic tomography detects weak sections of the depth) in the southern San Gabriel Mountains to 7.5 s (~23-km seismogenic crust, facilitating the assessment and mitigation of depth) in the northern San Gabriel Mountains. The zone bends earthquake hazards. The crustal weakening may be caused by downward beneath the surface traces of the San Gabriel and San active volcanoes, magma chambers, and overpressurized fluids in Andreas faults. It is brightest between these two faults, where it is fault zones. given the name San Gabriel Mountains “bright spot” (SGMBS), and becomes more poorly defined south of the San Gabriel fault and north of the San Andreas fault. The polarity of the seismic signal at the top of this zone is clearly negative, and our analysis OFF-SCALE suggests it represents a negative velocity step. The magnitude of the velocity step is approximately 1.7 km/s. In at least one READINGS FROM AUTHORS WHO ARE NOT location, an event with positive polarity can be observed 0.2 s EARTH SCIENTISTS BUT WISH THEY WERE beneath the top of this zone, indicating a thickness of the order of 500 m for the low-velocity zone at this location. “A Bad Earthquake at Once Destroys Several factors make the preferred interpretation of this bright reflective zone a young fault zone, possibly a “master” Our Oldest Associations” decollement: (1) It represents a significant velocity reduction. If the rocks in this zone contain fluids, such a reduction could be caused A bad earthquake at once destroys our by a differential change in fluid pressure between the caprock and the rocks in the SGMBS; near-lithostatic fluid pressure is required oldest associations: the earth, the very in the SGMBS. Such differential changes are believed to occur in emblem of solidity, has moved beneath our the neighborhood of active fault zones, where “fault-valve” action feet like a thin crust over a fluid; one second has been postulated. Less likely alternative explanations for this velocity reduction include the presence of magma and a change in of time has created in the mind a strange composition to serpentinite or metagraywacke. (2) It occurs at or idea of insecurity, which hours of reflection near the brittle/ductile transition, at least in the southern San Gabriel Mountains, a possible zone of concentrated shear. (3) A would not have produced. In the forest, as a thin reflection rising from its top in the southern San Gabriel breeze moved the trees, I felt only the earth Mountains projects to the hypocenter of the 1987 M 5.9 Whittier Narrows earthquake, a blind thrust-fault earthquake with one tremble, but saw no other effect. In the city, focal plane subparallel to the reflection. Alternatively, one could the houses, from being built of wood, did argue that the bends or disruptions in the reflective zone seen at the San Gabriel and San Andreas faults are actually offsets and not fall; they were violently shaken, and the that the reflective zone is therefore an older feature, possibly an boards creaked and rattled together. The older fault zone. people rushed out of doors in the greatest 390. Zhao, D. and H. Negishi, The 1995 Kobe Earthquake: Seismic alarm. It is these accompaniments that Images of the Source Zone and Implications for the Cause of Rupture Initiation, Journal of Geophysical Research, 103, pp. 9967– create that perfect horror of earthquakes, 9986, 1998. experienced by all who have thus seen, as To understand what may have triggered the 1995 Kobe, Japan, well as felt, their effects. earthquake (M 7.2) and how the rupture proceeded after initiation, Charles Darwin we determined high-resolution 3-D P and S wave velocity and Poisson’s ratio structures in the Kobe epicentral area, and Voyage of the Beagle relocated the aftershocks with the obtained 3-D velocity model. We February 20, 1845 used 64,337 P and 49,200 S wave high-quality arrival times from

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 26 S C E C Southern California Earthquake Center

Charles Richter Part Two by Michael R. Forrest

Fear is the fate of those who come to creep— Some herded by the local imps, like sheep. Not mine; I know my way, and have no fear; I have an errand and a purpose here.

Photo courtesty California Institute of Technology Photo courtesty Institute of California —CHARLES RICHTER, 1937

In the first part of our two-part chronicle of the life of seis- The earthquake and its deploy more seismometers as mologist Charles Richter, Dr. Forrest looked at Richter’s child- aftershocks damaged hundreds well as to analyze, interpret, hood, his education, and the development of the Richter scale. of buildings, twisted rail lines, and archive the accumulating In this final installment, he shows both the man and the sci- and devastated farmland by data. Though Richter generally breaking irrigation channels was enthusiastic about entist in his prime and beyond. Dr. Forrest drew heavily on and changing groundwater fieldwork, his coworkers on the Richter papers held by the California Institute of Tech- flow. The rupture area still has this and other trips would nology Archives, which generously gave permission for use slightly higher-than-average sometimes steer him to other of the material here. background seismicity, which tasks, such as making dinner. may be due to continuing “Charles may have been a n his youth, Charles assistant professor of seismol- aftershocks. The earthquake genius in many ways, but he Richter was a nervous and ogy at Caltech from 1937-47. was the first of three (including was anything but a mechanical Ishaky-handed farmboy After the war, he was pro- the 1987 Whittier Narrows and genius,” said Clarence Allen of who found most human moted to associate professor. It 1994 Northridge events) in the his mentor, remembering (from interaction painful. During the wasn’t until 1952 that Richter second half of this century to later fieldwork in Mexico) second half of his life, he became a full professor. demonstrate the possibility of “several bright blue flashes in developed into one of the Coincidentally, because the M damaging earthquakes on his attempts to get various nation’s best-known seismolo- 7.5 Kern County earthquake hit faults with little or no surface wires connected.” gists. that same year, funds appropri- expression. ated for earthquake science at The shy farmboy went on to Business of Earthquakes Caltech were greatly increased. “This event had the normal become president of the Years later in a letter to Hugo effect of earthquake disasters In 1957, Frank Press became Seismological Society of Benioff, he asked, “Wonder on seismology; after it, means director of Caltech’s seismo- America. He received fellow- what we would be doing now became available to expand logical laboratory. Because of ships from the Geological without the Kern County both in terms of equipment the growth in staff and Society of America, American earthquake in 1952.” and of personnel,” wrote equipment following the Kern Geophysical Union, Royal Richter of the event. Fortu- County earthquake, the lab Astronomical Society, Royal nately for the seismologists of was moved into the Thorsen Society of New Zealand, and The Kern County event that time, they were deploying Mansion in San Rafael. The American Academy of Arts occurred on July 21 on the left- field instruments to monitor a new lab was actually a true and Sciences. He received the lateral oblique reverse White nearby quarry blast when the millionaire’s Spanish house. It Medal of the Seismological Wolf fault, 23 miles south of earthquake hit. “In a few had decorated ceilings, marble Society of America. He was Bakersfield. It was the largest weeks, more significant data floors, wrought-iron balus- author or coauthor of about 100 earthquake in southern bearing on earthquake mecha- trades, and flagstone court- scientific papers. California since the 1872 nism and local structures were yards. The dining room became Owens Valley earthquake. It accumulated than in the a library. Blackboards were Richter’s rise in academia was shook Reno, San Francisco, Los preceding 20 years.” affixed to the walls of former slowed first by the Great Angeles, and San Diego, bedrooms. Bathtubs were Depression and then by World causing twelve deaths and $50 Immediately after the earth- covered with plywood so that War II. He worked as an million in property damage. quake, Richter rushed to records could be stored there.

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 27

A tunnel under the house was stations give three compass In the lab’s early days, there compendium of almost converted to an instrument settings and pinpoint the were maybe 15 seismometers everything seismological, with vault. Benioff and Press both epicenter. More than three is recording earthquakes for all of a strong emphasis on field converted bedrooms into better.” When it was readable, southern California. The data aspects of the science. Is there a offices. Kei Aki, SCEC’s Richter and his crew also read from all the stations were not seismologist in the world who cofounder and first science the amplitude, or peak always available quickly. In does not have this book on his director, used the kitchen. A deflection, of each quake at those conditions, his estimating or her shelf? And is there breakfast room was converted each station. This was the basis skills were more important anyone among us who does into Richter’s office. A note for the magnitude scale. Each than they would be today. not refer to it occasionally, attached to the front of his desk of the stations was equipped despite its present 30 year In the same way that the read “You have a theory, I have with at least one Wood- age?” wrote Clarence Allen southern California public a hypothesis, but he is just Anderson seismograph, which some years after Richter’s today has grown comfortable guessing!” was the standard of the day for death. hearing from Lucy Jones recording the high-frequency Not the tidiest man, Richter (USGS) or Kate Hutton “Richter was a keen observer, energy of local earthquakes. was said to have the habits of a (Caltech) after a significant a man of letters, an excellent teenager. According to one “Aside from magnitude he also earthquake, Richter was the linguist,” says Kei Aki, who colleague, “He works at a looked at different phases. He seismologist of choice in the believes the book is one of the cartoonist’s idea of a desk.” best ever written on earth- However, Richter always quakes. The book, originally seemed to know in which stack “In one sense, we can already predict earth- written from Richter’s intro- and at roughly what level to quakes sufficiently for practical purposes. We ductory earthquake letters, find a paper he needed. reflects both his voracious know where the areas of danger are and what reading habits and consider- The new laboratory staff had able writing experience. It was its first meeting in December 2, structures in those areas are unsafe.” (Richter) used for many years in 1957. Its first lunch was held in Richter’s elementary seismol- a beautiful convention hall, the was very good at looking at the 1950s and 1960s. Old-time ogy classes and after he retired, decor of which suggested a different wiggles coming in,” Angelino earthquake fans will but it is no longer in wide- meal of “champagne and recalls USC seismology tell you—with great passion— spread use. Compared to more caviar” to one attendee. In professor Leon Teng. “He that he was actually more modern texts, it reads like an reality, everyone ate what they would take the seismograms of famous throughout the encyclopedia, and, of course, always ate: sack lunches. a large earthquake—M 6 or southland in his day than any seismology has exploded with Richter would work at this M 7—with a very long time seismologist is now. new data and information mansion-lab until his retire- series, and he would be able to since Richter’s day. ment. The public and the press loved say ‘this is PKP’ or ‘this seems him. The media generally Richter—as a child—read Richter’s primary job in the lab to be exactly the same seismo- didn’t want to hear from everything he could get his was to archive earthquake gram as one I saw five years anyone other than Richter. hands on. He read in English data. He worked in a large ago.’” Teng also remembers With his facial twitch, bird-like and seven other languages. He measuring room studying that Richter could tell that an nervous energy, odd voice, particularly loved science seismogram after seismogram, event was caused by a blast serious demeanor, dry wit, fiction. Richter himself wrote a hour after hour. from a certain quarry or encyclopedic memory, absolute significant body of poems, originated in the south mastery of the seismogram, essays, letters, and journals “He read the arrival times of Pacific—all by looking at intense eyes, and his sharp, from his twenties. Richter even the earthquake waves at each squiggly lines. station off the seismograms flawless, definitive pronounce- worked on several novels, with a ruler and magnifier, and ments on things seismological, including House on a Bridge— who’d want to hear anyone which he wrote the results on 5-by-8 When large earthquakes else? Even after he retired, the index cards specially printed occurred, Richter would sit in a press preferred calling Richter with a form to receive the data. chair with the lab’s telephone after a big earthquake to hear We have about 30 file cabinets in his lap so that only he could his pontifications. full of these, covering the answer the calls. Some detrac- period 1932 through some time tors suggested he did this to in the 1980s.” says Caltech promote himself. Actually he One of the Best Books Ever seismologist Kate Hutton. was doing his job: gathering In 1958, Elementary Seismology information, locating earth- by Charles Richter was “The earthquakes were located quakes, and making the data published. “In my opinion, HENSLEY on a map, using a compass. available as fast as possible. He Charles’ greatest contribu- JIM

Measurements from each also didn’t think that anyone tion to science is his book. It is : recording station tell the else armed with only prelimi- sometimes thought of as a distance from the quake to the nary information could answer textbook, but it is far more than station, so readings from three calls from the press as well. that; it is a truly remarkable ILLUSTRATOR

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remembers a colleague from change, and as time went by, or radio rather than watching that time. when Richter saw what could an orchestra because he could be done with computer control and focus on the Richter, nevertheless, enjoyed analysis, he became more musical experience more the trip immensely. “There is a comfortable with the ever- successfully. “Watching the great deal in Japan that is very growing steel, concrete, and motions in the orchestra may beautiful, and the Japanese glass towers. indeed have a hypnotic effect themselves have a strong sense resulting in increased sensibil- of beauty and tend on the whole to preserve it. They have a tradition of courtesy that “Toward the mitigation of the disastrous conse- makes any contact with the quences of earthquakes, there could be no more older generation pleasant, whereas contact with the promising step than to organize an international younger generation was apt to be less so.” The Tokyo home of exchange of experience and ideas.” (Richter) the Richters was across the street from Premier Kishi’s, A Private Life ity and even bringing about a where students rioted to In the mid 1930s, Richter and feeling of enthusiasm which his wife, Lillian, joined the may or may not be justified,” Fraternity Elysia, a nudist wrote Richter in a letter to organization, beginning a Leon Knopoff in 1963 (it’s hobby he would combine for unclear whether it was ever many decades with another sent). “I recall a Heifitz recital activity he loved—hiking. In in Los Angeles when he and I the tradition of Whitman, were much younger. His Richter would don his back- presentation was utterly cold, pack and hike for weeks at a technical and supercilious [as if time in the high Sierra. On to say] ‘anything is good these rambles, he would write enough for these peasants’— poetry and reflect on life, and he was right; they ap- science, and nature. plauded anything and every-

Photo courtesty California Institute of Technology Photo courtesty Institute of California thing. I could not get out of the Charles Richter demonstrating his low-tech methods of measuring the world. In the 1960s, as Richter was hall soon enough.” becoming the grand old man of envisioned as one of a quartet. protest a proposed visit to seismology, he had a seismo- Retirement Japan by President Eisenhower. graph installed in the living The book follows four charac- Though Richter was still room of his house. Lillian “was ters through life. Unfortu- When Richter came back from subject to bouts of almost a little upset at first,” said nately, he never finished his Japan, he was so enthusiastic debilitating depression, which Richter, “but it was received novels. about his visit and Japanese had plagued him for much of enthusiastically by her girl culture in general that he spent his life, many people perceived Some who heard Richter friends. It makes a wonderful an entire lecture of his gradu- a mellowing once he retired in lecture publicly on seismology conversation piece at parties. ate seismology class discussing 1970. They found him more remember him fondly. He Now, she wouldn’t be without the Japanese language and approachable. He is said to could make wry comments that one.” would send audiences into fits characters, writing many on have laughed a bit more. He of laughter. Others remember the blackboard. The seismograph was a became a beloved elder his seismology classes in the convenience for Richter. statesman of seismology, and the role suited him. 1960s, when he had tenure and In the early 1960s, Richter gave Reporters would call him after a tremor, and he could simply was getting a bit older, as dry a number of talks to different His retirement party at Thorsen amble into the living room, and somewhat disorganized. groups in which he said that Mansion included the faculty look at the seismograph, and buildings in Los Angeles and staff at the time, very few tell the reporter something In 1959, Richter traveled to shouldn’t be built over ten or old timers. As with most about the shock. Tokyo University, where he 12 stories (also more recently retirements, it was a bit was a Fullbright research suggested by Caltech’s Tom anticlimactic and predictable, scholar for a year. It was the Heaton). At the time, there Music was a great love of except for a clever song sung only time he left Caltech. He were no real high-rise build- Richter’s. Though some of his by colleagues and students. never took another sabbatical. ings in downtown Los Angeles. contemporaries report that “The Richter Scale” was “He was worried during the Our skyline would look Richter had no feel for music— written by Caltech professor J. whole time he was away in radically different had even disliked it—he was Kent Clark. The song infuri- Japan. He thought California Richter’s ten-story ceiling been passionate about it. He seemed ated Richter, who had a well- couldn’t do without him,” heeded. The skyline began to to prefer listening to a record developed, if dry, sense of

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 29 humor about a great number of that suggestion at the time. Machines and a friend of Abe Lincoln. things—except his own science Today, scientists who study the Grind angrily Richter’s plot lies far from the apparently: area concur on a probabilistic Beyond a flimsy fence. ornate nineteenth-century analysis that reflects Richter’s Too much, already, that they scare gravestones and mausoleums. It measured 1.2 on the Richter Scale, The birds. A shabby little shiver; earlier hypothesis. Richter probably had enough money to have his wife and 1.2 on the Richter Scale— One of many anecdotes Gardens himself placed in a prominent A queasy little quiver . . . Lindvall remembers as typical Should range abroad, Not be confined like this— spot in the cemetery. Instead, of Richter occurred in the 1970s This jeweled island in a sea he chose a private, nondescript when the city of Downey asked In 1972, Richter helped found Of dust. corner for his bones to be him to about whether a fluid- Lindvall, Richter and Associ- rattled by the P, S, and L waves injection oil-recovery project ates. The consulting firm was he loved to study. Unlike many would cause earthquakes. In his later years, Richter the brainchild of Eric Lindvall, of the nearby grave markers— father of SCEC scientist Scott seemed to have had few regrets He gave them a concise which are covered with mud Lindvall and son of the dean of other than a common one—not answer: it wouldn’t—it’s too and overgrown grass—it engineering at Caltech. “It having made the most of time shallow. When he finished, one appears as though someone became obvious to me that spent with old friends and of the council members said, visits his plot, trims the grass, something should be done mentors. For example, he “Thank you, but could you put and wipes the earth off his about earthquake protection,” regretted not having attended it in terms that we can under- name. says Lindvall after the 1971 as many lectures at Caltech as stand. Is it 90 percent sure that Sylmar earthquake. possible in his younger days— nothing would happen, or how such as those given by Albert EPILOGUE LR&A would complete seismic would you phrase it?” After 10 Einstein. hazards analyses for building seconds, 20 seconds, Charlie Richter and Northridge Richter wrote warmly of such sites or act as consultants in said, “If I told you that it was In a little-known jest of fate, figures from his past as Hugo litigation involving earthquake 95 percent, you wouldn’t know Richter became a victim of the Benioff, Harry Wood, and the damage. “Richter was active in what that meant either.” There Northridge earthquake. After mathematician Harry Bateman, the firm until the last year or wasn’t another question about he died, his nephew inherited of whom Richter tells several two before his death. He’d be earthquakes. many of Richter’s personal in the office two or three times humorous stories that demon- Lindvall still misses his old belongings. They included rare a week. When we’d have a strate both Bateman’s feats of colleague. “Personally, we books of science, art, and review of existing facilities or mathematical genius and weren’t very close. But from a literature; a beautiful cherry- of a seismic hazard, he would Richter’s appreciation. scientific, technical, and wood desk; and irreplaceable write a chapter on the seismol- Gutenberg does not fare as well professional standpoint there objects like home movies and a ogy. When Dr. Richter said in Richter’s writings. was always something new.” diary that described Richter’s something, there weren’t many On the last day of September meeting with Einstein. people who would argue with Reflection 1985, Richter died in a conva- Richter’s nephew thought he him,” recalls Lindvall. lescent home from congestive “I’ve been working fewer was prepared for an earth- heart failure. He was 85. From With regard to his science, hours since retirement, though quake, his awareness height- an Ohio farm to Caltech, from Richter was incorruptible. not by choice. I’ve found ened by many interactions reciting the names on his Because of this, lawyers Father Time has caught up with his uncle. The house was mother’s flash cards in three avoided using him as an expert with me,” said Richter of his stocked with emergency food languages to co-inventing the witness. He never took sides; retirement. After retiring, and water and covered by field of seismology, from he would present his findings Richter, using the penname earthquake insurance. After the painful shyness to meeting and analyses. When lawyers John Florio, published quite a 1994 Northridge earthquake, a Einstein and Millikan—a tried to shape his testimony bit of his poetry in a small local quake-related fire burned remarkable journey. The fire into a more favorable presenta- newspaper. down the nephew’s Granada and the fury of a passionate, tion, Richter would refuse to Hills home. The family His poetry mirrored the more brilliant, wise, unconventional change a word. escaped, but Richter’s belong- whimsical and philosophical man passed into ings were destroyed. Richter’s method was at least corners of his psyche, at times silence. two decades ahead of his time. displaying the sentiments most Unlike most scientists involved people would not have thought The author is deeply indebted to in hazard analysis at that time, him capable of feeling, much the Caltech Archives for access to he wouldn’t consider only the less expressing, as in “City the Richter papers and permission known faults and the earth- Park in April” (1973): to quote and refer to them quakes they might produce in He was throughout both articles. The author also thanks a great number buried in Moun- his analyses. Richter always Always, of people who prefer not to be assumed one of M 6 or greater The tiny fears— tain View Cemetery near mentioned as well as those quoted. could occur directly under a Will there be daffodils? Lillian who had died of cancer Additional thanks to Mary Melton given site on an unknown Have tulips been set out again in 1972. In the same cemetery and Ann Connors of the Los fault. Most developers rejected This spring? are a governor of California Angeles Times Sunday Magazine.

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Foreign Earthquake Studies Central American Workshop in

By Hugh Cowan Panama border in southern damage associated with the Hazard Assessment and Costa Rica. The recent Man- rupture of this local fault Urban Planning agua workshop involved a system. In the years following the 1972 work session in larger number of participants On March 31, 1931, a shallow earthquake, considerable work paleoseismology was from all countries in Central earthquake of M 5.3-5.9 was undertaken to map the recently held in America. We were fortunate to A produced surface rupture local faults and evaluate the Nicaragua as part of a seismic attract several experienced along a NNE-trending fault seismic hazard in Managua microzonation project in the instructors from the U.S. and (Falla Estadio) in the western and nearby centers. Consult- capital, Managua. Seismic Europe. part of Managua. The urban ants performed much of that microzonation for Managua Additional sponsorship and population at that time was work, incorporating state-of- forms part of a Central logistic support was provided around 40,000. About 1,000 the-art industry practices. people were killed. Central Significant accomplishments districts were severely dam- during the 1970s included the The recognition of prehistoric surface ruptures on aged due to the collapse of identification and mapping of buildings and by the fires that major faults in metropolitan faults with no historic record of movement repre- followed (Sultan, 1931). Managua and the development sents an important contribution to the local per- of a logical framework for fault Forty years later, the popula- hazard evaluation in urban ception of seismic hazard, which hitherto has tion of Managua had swelled planning (Woodward-Clyde to around 500,000, and the city Consultants, 1975; Dames and been strongly influenced by the historic events. was struck again by an Moore-Lamsa Consortium, earthquake (M 5.6, M 6.2) on b s 1978). December 23, 1972. The impact American regional program of of the 1972 event was devastat- Many of the consultants’ by the International Lithos- earthquake hazard reduction, ing. Structural collapse and fire recommendations were phere Program (ILP) and the which is funded by the destroyed the western sector of enshrined in local planning local host organization— Norwegian Agency for the city, including the down- regulations, but in subsequent Instituto Nicaraguense Development Cooperation town area: 11,000 people died years competing priorities (and Estudios Territoriales. (NORAD) and coordinated through a regional secretariat, Centro de Coordinacion para la Why Managua? Managua, with a current population estimated at Prevencion de Desastres The capital of Nicaragua, 1,000,000, is one of the most vulnerable urban Naturales en America Central Managua, is located at the (CEPREDENAC). Central American volcanic centers in Latin America. Since the late 1980s, the chain on the southern shores of countries of Guatemala, El Lake Managua. The NW-SE and 20,000 were injured. More relative seismic quiescence) Salvador, Honduras, Nicara- trending volcanic chain than 200,000 people were left meant that little new work was gua, Costa Rica, and Panama exhibits a pronounced offset of homeless, and the economic undertaken to evaluate active have collaborated in a program about 15 km to the south across cost in that year alone ex- faulting. More recently, of natural hazard assessment Managua—from Volcan ceeded 40% of the GNP. however, both the and disaster preparedness, Momotombo on the northwest CEPREDENAC program and which is intended to avert shore of Lake Managua to local institutions have refo- future suffering and economic Masaya Caldera southeast of The 1972 earthquake ruptured cused on natural hazard and losses such as those caused by the metropolitan area. four NNE-trending faults, of vulnerability assessment. earthquakes in El Salvador which the largest is Falla Managua, with a current (1986), Guatemala (1976), and Within the step-over region, Tiscapa. The sense of displace- population estimated at Nicaragua (1972). which includes metropolitan ment was left-lateral oblique- Managua, a closely spaced slip, with aggregate horizontal 1,000,000, is one of the most A recent component of the system of strike-slip and movements in the range 2 to 38 vulnerable urban centers in CEPREDENAC program has oblique-normal faults shows cm, and a minor vertical Latin America. been the introduction of cumulative evidence of component on three of the four paleoseismology to seismic repeated late Quaternary faults (Brown et al, 1973). Paleoseismology Work hazard assessment of major movement along a north- Aftershocks defined a rupture active faults. The first study of northeast trend. Twice during zone extending several Session that kind was conducted in this century, Managua has kilometers beneath Lake The 1931 and 1972 earthquakes April 1997, adjacent to the suffered severe earthquake Managua, <8-10 km deep. were associated with fault Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 31

New Quake Concerns at Nuclear Paleoseismology Dump Site ruptures in the western part of shoreline of Lake Managua, eologist Brian and the U.S. Nuclear Regula- Managua, but the longest which is offset vertically about Wernicke (Caltech) and tory Commission, Wernicke identified surface faults (Falla 2 m across the fault. Ghis colleagues have and his colleagues set up ten Aeropuerto, >20 km, and Falla discovered that Nevada’s Global Positioning Satellite Cofradia, about 40 km) are, in Yucca Mountain, a proposed (GPS) receivers among the two fact, located in the eastern part The People site for a federally run nuclear California fault zones and five of the graben. Neither fault has The participants worked long waste dump, is at least ten receivers in a line that cut been associated with historic days in intense heat with great times more likely to experience across Yucca Mountain. Based rupture, yet both Falla enthusiasm. There was broad an earthquake or volcanic on GPS information from the Aeropuerto and Falla Cofradia participation among physics, satellites alone, the crust near were recently observed to engineering, and geoscience displace young sediments close graduates. The fieldwork was to the Lake Managua shoreline. supplemented with evening Furthermore, Falla Aeropuerto lectures on a variety of topics, offsets both the modern including site selection criteria, Based on GPS information from the satellites shoreline and a prehistoric field techniques, dating alone, the crust near the mountain is heading shoreline of Lake Managua. methods, recognition of faulting styles, seismic hazard west-northwest at nearly 2 mm a year—roughly The Fieldwork analysis, and sensitivity testing. We concluded a busy three to four times the average for the Basin and Our fieldwork focused on Falla week with a tour of the Range region in which Yucca Mountain sits. Aeropuerto in an attempt to surroundings of Managua, quantify the ages of landforms including the Masaya and and sediments along the Apollo calderas. northern section of the fault. The workshop commenced In summary, the work session eruption than previously the mountain is heading west- with air-photo analysis of was very rewarding both as a thought. northwest at nearly 2 mm a several localities, followed by scientific investigation and as a year—roughly three to four walk-over surveys to select training exercise. Furthermore, The findings, published in a times the average for the Basin suitable localities for excava- the recognition of prehistoric recent edition of Science, come and Range region in which tion. Three trenches were surface ruptures on a fault with at a time of intense debate in Yucca Mountain sits. subsequently opened along a no historic record of movement Washington over high-level 300-m section of the fault, and (Falla Aeropuerto) represents radioactive waste from the Wernicke acknowledges that leveling profiles were con- an important preliminary nation’s 109 commercial answers to questions about the structed across all surfaces. contribution to the local nuclear plants. sources of the strain including where and how the strain is The kinematics of faulting perception of seismic hazard, Federal courts have ruled that most likely to be released appeared to be dominantly which hitherto has been the U.S. Department of Energy would require additional strike-slip, probably left-lateral, strongly influenced by the must take the waste, but the measurements. with a component of normal historic events. DOE counters that it can’t take offset down to the east. Two any before the President paleoearthquakes are inferred Training opportunities in approves a permanent site. Planned seismic- and volcanic- from the composite stratigra- paleoseismology and Quater- hazard assessments for the phy that includes volcanic nary tectonics for young To speed the hand-over of DOE’s Yucca Mountain project agglomerate, lacustrine, and Nicaraguan graduates should waste, both houses of Congress have already been completed, fluvial sediments and peat. be required as follow up in have passed bills that would says Richard Quittmeyer, a order to consolidate the designate Yucca Mountain as a seismologist involved with the Dating of several organic benefits of the workshop. temporary storage site despite Yucca Mountain project- samples is pending, but the Similar needs exist throughout President Clinton’s threat to management team. Yet the faulted horizons in all trenches Central America. We would be veto any such measure. The study could reopen the contained Pre-Colombian interested to hear from persons study could become the latest discussion about seismic risks pottery (of unknown age), or institutions that could assist rallying point for opposition to at the site. For more informa- whereas unfaulted horizons in in meeting these needs. For Yucca Mountain as a perma- tion on Yucca Mountain site all trenches contained ceramics more information concerning nent nuclear-waste facility. and the issues and studies inferred to be of Spanish-colonial participants and references, concerning it, refer to the age. We hope to be able to contact Hugh Cowan: Financed with grants from the following web site: bracket the age of a paleo- [email protected]. National Science Foundation WWW.YMP.GOV. Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Page 32 S C E C Southern California Earthquake Center

Calendar July 15—Newsletter 4.3 articles and [email protected]; web: copy due to editor. Contact Ed WWW.GEOSOCIETY.ORG. June 8-12—IRIS meeting, Santa Cruz: Hensley, 916/353-9996. 21-23—SCEC workshop held in contact Susan Strain: 21-25—International Association of November Utah on the physics governing [email protected]. Tentative: SCEC- Engineering Geologists & the behavior of earthquakes and sponsored education modules to be 11-15—Fourth International Canadian Geotechnical Society: 8th faults. demonstrated in workshop Conference on Corporate “Seismo Software for the Class- Congress of IAEG and the Earthquake Programs, Shizuoka, 24-26—Western United States room.” Environment. Vancouver, BC. Japan. Contact Steve Vukazich, Earthquake Insurance Summit, Theme: A Global View of the 10-23—Summer school in “Active conference chair, San Jose State Sacramento, CA. For informa- Pacific Rim. Contact: Faulting and Paleoseismology,” University, 408/924-3858 or email tion, contact Western States [email protected]; or Luxemburg. Contact Dr. M. [email protected]. Seismic Policy Council: 415-974- WWW.BCHYDRO.BC.CA/IAEG/. 15—Newsletter 4.4 articles and 6435 or [email protected]. Meghraoui, email: [email protected]. 21-25—Earthquake Prognostics copy due to editor. Contact Ed 26-July 1—Disaster Forum ‘98: World Forum: Seismic Safety of Big 15—Newsletter 4.2 articles and Hensley, 916/353-9996. Global Partnerships Creating Cities, Istanbul. Contact Dr. M. copy due to editor. Contact Ed Solutions, Edmonton, Alberta, Hasan Boduroglu, Istanbul Hensley, 916/353-9996. December Canada. For information, email Technical University, [email protected] [email protected]. 7-10—American Geophysical or visit the web site: August Home page: WWW.INS.ITU.EDU.TR/ Union Annual Meeting, San Francisco, California. WWW.FREENET.EDMONTON.AB.CA/ 23-28—The XXVI General EAEE/BIGCITIES98.HTML. DISASTER. Assembly of the European 28-July 3—Gordon Research Seismological Commission (ESC), October January 1999 Tel Aviv. Conference home page: Conference on the “Interior of 17-20—SCEC Annual Meeting, 10-14—Session planned for the HTTP://WWW.GEO.IPRG.ENERGY.GOV.IL/ the Earth” at New England Palm Springs, CA. Contact John World Archaeological Congress, SD/ESC2.HTML. ESC home page: College in Henniker, NH. McRaney, SCEC Administration, Cape Town, South Africa. HTTP://WWW.GSRG.NMH.AC.UK/ESC/. Contact Mike Gurnis 213/740-5843. “Catastrophism, Natural [email protected] or John Disasters, and Cultural Change.” 22-23—Institute for Business & Vidale [email protected]. Interior September Info: WWW.UCT.AC.ZA/DEPTS/AGE/ Home Safety 1998 Congress. of the Earth web page: WAC/ 15-18—Western States Seismic Orlando, FL. Contact: Karen WWW.GPS.CALTECH.EDU/~GURNIS/ Policy Council 20th Annual Gahagan at [email protected] or see 15—Newsletter 5.1 articles and GORDON.HTML. Web page for the Conference, Pasadena, California. web: WWW.IBHS.ORG. copy due to editor. Contact Ed GRC: WWW.GRC.URI.EDU/ See WSSPC for more information: Hensley, 916/353-9996. 26-29—Geological Society of email [email protected] or web America Annual Meeting. Toronto, WWW.WSSPC.ORG Canada. Contact: (800) 472-1988;

SCEC Notes • SCEC Notes • SCEC Notes • SCEC Notes • SCEC Notes

Bob Yeats of Oregon State Dapeng Zhao used to be a Congratulations, Sara. On Sergio Chavez-Perez University is the 1998 recipient member of the research faculty May 8, SCEC Outreach graduated last December with of the Michel T. Halbouty in earth sciences at USC. Now Education Specialist Sara a Ph.D. in geophysics from the Human Needs Award from the he’s in Japan as of February Tekula was recognized at UNR. He’s working now at the American Association of 1998 as a tenured associate USC’s commencement. Mexican Institute of Petroleum Petroleum Geologists. The professor at Ehime University. Although she officially as a research geophysicist award, presented at the annual Update your address books for completed her undergraduate specializing in seismic imaging meeting of AAPG at Salt Lake the new associate professor in studies in December of 1997 and migration. Email him at City in May, is in recognition of Matsuyama: [email protected] with a B.A. in psychology, this [email protected] Bob’s use of geological data U.AC.JP. And on the web: HTTP:// made it “official.” Family from petroleum-industry well PRECISION.ENG.SUNYSB.EDU/DALIAN4. members traveled from New logs and seismic profiles in York to share the experience. Mark Stirling successfully earthquake hazard mitigation Sara is the first in her immedi- defended his Ph.D. in April. in southern California. Bob’s Chris Walls and Maria ate family to graduate from a His thesis was an analysis of email address is Herzberg recently took staff four-year college. the seismic hazard in so. Cal & [email protected]. consulting positions with Earth New Zealand. Congratula- Consultants International. Both tions, Mark. We’ll look forward are graduates of SDSU in to hearing where you go from geology. here. [email protected]

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 33

Earthquake Information Resources Online SCEC on the Web www.scec.org

Earth Sciences

SCEC Data Center HTTP://GLDSS7.CR.USGS.GOV/ National Earthquake Information Center HTTP://WWW.SCECDC.SCEC.ORG/ SCEC Data Center home page HTTP://GEOLOGY.USGS.GOV/QUAKE.HTML Earthquake Information HTTP://WWW.SCECDC.SCEC.ORG/RECENTEQS Recent earthquake activity in northern and southern Calif. Maps and HTTP://QUAKE.WR.USGS.GOV/ earthquake lists are interactive and updated at the time of an event USGS Menlo Park

HTTP://WWW.TRINET.ORG/EQREPORTS HTTP://WWW-SOCAL.WR.USGS.GOV Southern California Seismic Network weekly earthquake reports USGS Pasadena

HTTP://SCEC.GPS.CALTECH.EDU/FTP/CA.EARTHQUAKES HTTP://GEOHAZARDS.CR.USGS.GOV/NORTHRIDGE/ SCSN weekly & monthly earthquake reports (archives to Jan. 1993) USGS Response to an Urban Earthquake — Northridge ’94

HTTP://WWW.SCECDC.SCEC.ORG/SEISMOCAM/ HTTP://WWW-SOCAL.WR.USGS.GOV/NORTH Caltech/USGS Seismocam: waveform displays of data 30-seconds-old Summary of work of USGS after Northridge ’94, including datasets earthquakes in southern California: includes aftershock maps, HTTP://WWW-SOCAL.WR.USGS.GOV/LISA/NETBULLS animations of aftershock sequences and rupture models, a clickable Southern California Seismic Network (bulletins) map of historic southern California earthquakes, and Putting Down Roots in Earthquake Country (online book) HTTP://WWW.SEISMO.UNR.EDU Nevada Seismological Laboratory HTTP://WWW.SCECDC.SCEC.ORG/EQSOCAL.HTML Main page Work by two SCEC-funded researchers, John Anderson and Steve Wesnousky. Contains lists, maps, and seismogram data from recent HTTP://WWW.SCECDC.SCEC.ORG/CLICKMAP.HTML earthquakes, including searchable earthquake catalogs and more Southern California clickable earthquake map HTTP://WWW.SCECDC.SCEC.ORG/LABASIN.HTML USGS email addresses HTTP://WWW.SCECDC.SCEC.ORG/EASOCAL.HTML Los Angeles basin clickable earthquake map [email protected] National Earthquake Information Center HTTP://WWW.SCECDC.SCEC.ORG/EQSOCAL.HTML Earthquakes in southern California [email protected] National Geomagnetic Information Center HTTP://WWW.SCECDC.SCEC.ORG/BYMONTH.HTML Time-lapse animations of southern California seismic activity [email protected] National Landslide Information Center HTTP://SCEC.GPS.CALTECH.EDU/CGI-BIN/FINGER?QUAKE “Finger Quake” ftp (updated frequently) Paleoseismology HTTP://WWW.SCECDC.SCEC.ORG/FAULTMAP.HTML HTTP://INQUA.NLH.NO/COMMPL/PALSEISM.HTML Southern California fault map The INQUA Subcommission on Paleoseismicity: content list and HTTP://WWW.SCECDC.SCEC.ORG/LAFAULT.HTML authors for the special issue of journal of geodynamics arising Faults of Los Angeles from the INQUA Berlin 1995 symposium on paleoseismicity.

HTTP://WWW.SCECDC.SCEC.ORG/LARSE.HTML LARSE home page Active Tectonics

HTTP://SCECDC.GPS.CALTECH.EDU/CATALOG-SEARCH.HTML HTTP://WWW-GEOLOGY.UCDAVIS.EDU/~GEL214/ Interactive SCSN seismicity catalog search page University of California, Davis—Active Tectonics • Lecture notes (“Contents”) HTTP://WWW.SCECDC.SCEC.ORG/EQCOUNTRY.HTML • Problem sets (“Problems”) for this course Putting Down Roots in Earthquake Country (online book) • WWW links (“Links”) of interest to students and researchers • References Seismo-Surfing the Internet GIS Web Sites HTTP://WWW.GEOPHYS.WASHINGTON.EDU/SEISMOSURFING.HTML Clearinghouse of research data & informmation HTTP://WAREHOUSE.GEOPLACE.COM/ Bibliography of GIS & environmental applications:

USGS Web Sites HTTP://PASTURE.ECN.PURDUE.EDU/~ENGELB/ Bernie Engel, professor of agricultural engineering: soil and water HTTP://WWW.USGS.GOV conservation, environmental issues, systems engineeering General USGS site Continued on next page . . .

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Online Resources continued

HTTP://WWW.LIB.BERKELEY.EDU/CGI-BIN/PRINT_HIT_BOLD.PL/UCBGIS/ HTTP://WWW.TRINET.ORG/ UCB GIS Task Force integrates GIS activities with other resources at Trinet—the seismic system for southern California UCB campus, recommends GIS services for library HTTP://ERP-WEB.ER.USGS.GOV/ HTTP://WWW.NWI.FWS.GOV/THINKTANK.HTML Recent USGS NEHRP Research Contracts GIS Think Tank on problems of digital mapping for users of NWI data HTTP://NCEER.ENG.BUFFALO.EDU/ENEWS Express news, customizable electronic service that alerts readers to HTTP://FGDC.ER.USGS.GOV/LINKPUB.HTML earthquake/hazards information selected from the most recent List of FTP directories for federal Geographic Data Committee NCEER Information Service News based on a reader’s interest HTTP://MIS.UCD.IE/STAFF/PKEENAN/GIS_AS_A_DSS.HTML profile. Paper on how to use a GIS as a DSS generator HTTP://WWW.CIVENG.CARLETON.CA/CGI-BIN/QUAKES HTTP://SPSOSUN.GSFC.NASA.GOV/EOSDIS_SERVICES.HTML Recent quakes (with a great map viewer) A spectrum of services, some for casual users, some for research HTTP://WWW.CRUSTAL.UCSB.EDU/SCEC/WEBQUAKES/ scientists, some inbetween Up-to-the-minute southern California earthquake map—latest 500 HTTP://WWW.GGRWEB.COM/ earthquake locations. Java-enabled browsers only. Services of information technologies, earth sciences, GIS, GPS, & HTTP://SMDB.CRUSTAL.UCSB.EDU/ remote sensing industries A relational database of information about and access to strong motion recordings.

Geodetic Information HTTP://WWW.CONSRV.CA.GOV/DMG/SHEZP/PSHA0.HTML HTTP://LOX.UCSD.EDU Probabilistic Seismic Hazard Map, California This site is the IGPP & Scripps Orbit and Permanent Array Center HTTP://WWW.ABAG.CA.GOV/BAYAREA/EQMAPS/LIQUEFAC/BAYALIQS.GIF (SOPAC) and features global (IGS) and regional (SCIGN) continuous Bay Area hazard map GPS archive, SCIGN maps, time series, and site velocities. HTTP://WWW.WSSPC.ORG Western States Seismic Safety Policy Council site, an overall GMT earthquake safety information source. HTTP QUAKE UCSB EDU :// . . HTTP://WWW.SCECDC.SCEC.ORG/GLOSSARY.HTML#BLIN Helps make shaded relief maps with GMT. Has catalog of maps Glossary of terms (in progress) produced by Geoffrey Ely at the ICS/UCSB. Downloadable digital elevation model for southern California in GMT-readable (netCDF) HTTP://WWW.GEOPHYS.WASHINGTON.EDU/SEISMOSURFING.HTML format. The grid covers the region 121W 115W 32.5N 35.5N at a Seismic Info Sources resolution of 3 arc sec. You can get to the web page from the ICS HTTP://WWW.SEISMIC.CA.GOV/SSCCATR.HTM home page, then click on Mapping, and then Geoff’s Map Catalog. California’s earthquake hazard mitigation plan

HTTP://WWW.SEISMIC.CA.GOV/SSCLEG.HTM Preparedness, Disaster Management Current state and federal bills being tracked by the Commission)

HTTP://WWW.BEST.COM/~TRBU/OES/ HTTP://WWW.SEISMIC.CA.GOV/SSCSIGEQ.HTM California Governor’s Office of Emergency Services: information on Seismic Safety Commission—significant damaging earthquakes Earthquake Preparedness Month campaign HTTP://SHELL.RMI.NET/~MICHAELG/WEEKSREVIEW.HTML HTTP://KFWB.COM/EQPAGE.HTML Biweekly earth science review KFWB Quake Page (by Jack Popejoy) HTTP://KFWB.COM/CUCAMONG.HTML Internet Discussion Groups KFWB Webservice exclusive: trenching the Cucamonga fault: [email protected] HTTP://WWW.HIGHWAYS.COM/LASD-EOB/ Western States Seismic Policy Council discussion group The Los Angeles Sheriff’s Emergency Operations Bureau [email protected] HTTP://WWW.JOHNMARTIN.COM/EQPREP.HTM Paleoseismic ListServe John A. Martin & Associates [email protected] HTTP://WWW.EERC.BERKELEY.EDU/ Global Volcanism Network Earthquake Engineering Research Center offers extensive, searchable database of abstracts, reports, and other resources. New: “Lessons [email protected] from Loma Prieta,”with papers, images, and data. Research in quaternary science

[email protected] Earthquake Information Sites Seismological discussion list (SEISMD-L)

HTTP://WWW.EQNET.ORG/ [email protected] EQNET Earthquake discussion list

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Southern California Earthquake Center S C E C Page 35

SCEC Quarterly Newsletter Southern California Earthquake Center

a component of the Center’s Outreach Program A National Science Foundation National Science and Technology Center For more information on in partnership with the SCEC Outreach Program, the United States Geological Survey see the Outreach Web page at WWW.SCEC.ORG OR contact: Administration Jill Andrews, Outreach Director Thomas Henyey 213/740-3459 or [email protected] Center Director Mark Benthien, Outreach Specialist 213/740-0323 or [email protected] David Jackson (general information, publications, WWW) Science Director Sara Tekula, Outreach Specialist John McRaney 213/740-2099 or [email protected] Director of Administration (education and community outreach) Jill Andrews To Subscribe: One year’s subscription costs Outreach Director $25.00. Please make payment by check, money order, or purchase order payable to “University of Southern California/SCEC.” Do not send currency. Price includes postage within the U.S. Overseas airmail costs or special courier services will be billed. SCEC scientists, students, Board of Directors and affiliated agencies receive this newsletter free of David Jackson, Chairman charge. University of California, Los Angeles Mail your name, mailing address, phone number, email, and check for $25 to: Bernard Minster, Vice Chairman Southern California Earthquake Center Scripps Institute of Oceanography University of California, San Diego University of Southern California Los Angeles, CA 90089-0742 John Anderson University Of Nevada, Reno Subscribers: Check your mailing label for the last issue of your current subscription. If “free” is Ralph Archuleta listed, you will continue to receive the newsletter University of California, Santa Barbara indefinitely. I f any changes need to be made to your address, please call 213-740-5843 or email Robert Clayton [email protected] California Institute of Technology Newsletter on the Web: WWW.SCEC.ORG/NEWS James Dolan Current issues can be accessed only by current recipients University of Southern California of the newsletter. Back issues are accessible without a password. The online newsletter will feature active links James Mori to other web pages with related information. To access United States Geological Survey the current issue online, enter the following when prompted: Thomas Rockwell username: scecnewsletter San Diego State University login: issue34 Leonardo Seeber Have questions? Call, fax, or email: Lamont-Doherty Earth Observatory Tel: 213/740-1560 Fax: 213/740-0011; Email: [email protected]

Southern California Earthquake Center Quarterly Newsletter, Vol. 4, No.1, 1998 Inside this issue: S C E C SCEC Quarterly Newsletter

Feature Articles SCEC Quarterly Newsletter is published quarterly by the South- ern California Earthquake Center, University of Southern Califor- Precarious Rocks ...... 3 nia, Los Angeles, CA 90089-0742, USA, telephone 213/740-1560 or 213/740-5843, fax 213/740-0011, email: [email protected]. Interview: Jean-Bernard Minster ...... 6

Seismicity of the San Joaquin Hills ...... 12 Producer: Jill Andrews Feature: Charles Richter, Part Two ...... 26 Editor: Ed Hensley Feature writer: Michael Forrest

SCEC Departments Contributing writers: Photography: From the Directors: Research to Reduce Hazard ...... 2 Jill Andrews, SCEC Jill Andrews, Sara Tekula, Lisa Mark Benthien, SCEC Grant, Mark Benthien, Michael SCEC News Briefs ...... 16 Forrest, Caltech Archives Thomas Henyey, USC/SCEC

Summer Interns ...... 20 David Jackson, UCLA/SCEC Editorial review: Linda Townsdin SCEC’s Research Program & Funded Projects for 1998 ...... 21 Sara Tekula, SCEC

SCEC Research Publications & Abstracts...... 24 Richter Photographs: “Off-Scale” ...... 25 Courtesy California Institute of Technology Archives Calendar ...... 32 Richter Illustration: Jim Hensley SCEC Notes ...... 32 Cover: Earthquake Information Resources Online...... 33 adapted from photo by James N. Brune

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