Issues

The Northridge earthquake of January 17, 1994 and the Kobe earthquake, which occurred one year to the day later on January 17, 1995 were both very damaging and disturbing events. The magnitude 6.7 Northridge earthquake occurred on a blind thrust fault that had not been identified as a potential seismic source, produced near-fault ground motions that were about 50% stronger than expected, and caused brittle failures in the moment frame connections of steel buildings located well away from the region of strongest shaking. Although the loss of life was moderate, in part due to its early morning occurrence, the earthquake caused direct losses estimated at about $30 billion. Although the magnitude 7 Kobe earthquake was not surprising geologically, it occurred on a relatively inactive fault in a region that conventional wisdom (and governmental policy) had grown to regard as being of low seismic risk. The scale of death and destruction...

INTRODUCTION

The Seismology Program of the Geological Survey of Canada (GSC) and its predecessor agencies (Dominion Observatory and Earth Physics Branch) have prepared seismic hazard assessments for input to seismic zoning maps for the National Building Code of Canada (NBCC) since the first zoning map appeared in the Code in 1953 (Hodgson, 1956). Subsequent updates to this early map have appeared in the NBCC in 1970 (Whitham et al., 1970) and 1985 (Basham et al., 1985). A recent review of this history of three generations of seismic zoning maps can be found in Basham (1995).

A fourth generation is now justified because there is sufficient new information available to improve the hazard estimates (Adams et al., 1995; Basham, 1995). The principal document describing the new seismic hazard model and results is GSC Open File 3283 (Adams et al., 1996), prepared to present the new results to the Canadian National Committee...

INTRODUCTION

Most large earthquakes that pose a danger of strong ground motion in Mexico City occur along the subduction zone where the Cocos plate is moving beneath the North American plate, one of the most active subduction thrust faults in the Western Hemisphere (Esteva, 1988). The earthquakes of September 19 and 20, 1985, measuring 8.1 and 7.5, respectively, originated on a segment of this subduction zone known as the Michoacan gap. The first of these two events killed 10,000 people, left tens of thousands homeless, and caused the collapse of over 200 multi-story buildings and serious damage to 757 other buildings. This seismic zone has generated 42 earthquakes of magnitude 7 or greater this century, and there is concern that the next major earthquake to affect Mexico City will occur along the Guerrero Gap of the subduction zone, which lies approximately 320 kilometers from the capital. This section of the...

INTRODUCTION

In recent years, data from geophysical and laboratory physics gravity experiments suggested the existence of an anomalous gravitational or “fifth” force (Stacey et al., 1987; Boynton et al., 1987; Thieberger, 1987; Fischbach and Talmadge, 1992). However, it appears that these data are better explained by improving the models of the Earth's gravitational field instead of making major adjustments in the basic theories of physics (Kim, 1988; Kim, 1989; Braswell, 1992). Detailed modeling of the Earth's gravitational field requires a knowledge of variations in density within the Earth as well as a knowledge of the shape of the Earth (Chulick et al., 1990). This in part is facilitated by the inclusion of a detailed model of the three-dimensional density structure of the Earth's crust. Such a model can be constructed by using the velocity and layer thickness data collected from various types of seismic surveys (Christiansen and Mooney, 1995). This...

INTRODUCTION

The Comprehensive Test Ban Treaty (CTBT) verification community is concerned with estimating capabilities to correctly identify the sources of regional seismic events whose magnitudes are in the range 2.5 < m_b < 4.0. This interest has developed, in part, from the recognition that commercial explosions such as quarry or mine blasts can account for a substantial fraction of the regional seismic activity in this magnitude range in many nations (Richards et al., 1992). Consequently, a variety of seismic methods have been developed to identify the sources of regional seismic signals generated by commercial explosions as well as those generated by earthquakes (cf., Baumgardt and Ziegler, 1988; Bennett et al., 1989; Dysart and Pulli, 1990; Harris, 1991; Hedlin et al., 1989; Stump and Reinke, 1988). Experience has demonstrated that successful application of these methods within one region does not guarantee their global applicability. Therefore, it is necessary to evaluate the...

AN INTRODUCTION TO THE EVENT

The Ardebil earthquake of February 28, 1997 (M_w 6.0) struck a populated area in the Ardebil province of Iran (west of the Caspian Sea; Figure 1) at 12:57:28 GMT (16:27:28 local time). The devastated area in the Ardebil province is located in a region between the city of Ardebil and the volcanic summit of Sabalan. The villages of Golestan, Shiran, Arjestan, Kalkhoran, Viladarreh, and the cities of Nir and Sarein (all in Ardebil province) have been totally or severely damaged (see Figure 1).

The last official news by IRNA (Islamic Republic News Agency) reports 965 deaths, about 2,600 injured people and more than 60,000 homeless. The search-and-rescue operations were difficult because the temperature in the affected area in this season reaches −28° Celsius, and the area is mountainous, which caused many landslides. The slope movements closed accessory roads and in some cases they buried some...

In preparing for this address, I realized that time was not sufficient to touch upon all facets of research conducted by Society members. So, with an apology to those members whose specific interests I ignore, and as a testament to the very diversity of our Society, I have chosen to limit myself to a brief discussion concerning the future of seismic hazard analysis and the intimate relationship between earthquake prediction research and seismic hazard analysis. It is perhaps most useful to place these ideas within a historical perspective. In my view, the roots of modern seismic hazard analysis emanate from the study of the great 1906 earthquake (Lawson and others, 1908; Reid, 1910), the same earthquake that served to catapult the SSA into existence. Meeting here as that Society more than 90 years past the earthquake is quite a compliment to the 1906 investigators. The works of Grove Karl Gilbert...

Introduction

Earthquake strong-motion data are useful for a wide array of seismological and engineering research and applications. Unfortunately, strong-motion data are often difficult to acquire. While they are available from a diverse set of organizations and services, knowing where to look in order to retrieve a particular set of records is, to put it nicely, complicated. This brief summary is intended to provide information on obtaining strong-motion records online (or in other digital form), contacting data sources, retrieving ground-motion parameters, and accessing products and information pertaining to strong ground motions.

The advent of the Internet has certainly made the acquisition of strong-motion data from recording organizations easier. However, there are many such organizations, and few have easy, direct approaches for providing the data to other users. Although I am not directly associated with any data source, I presently receive at least 5 requests per month for strong-motion data, simply because...

October 6–8, 1996
 Chapel Hill, North Carolina

ES-SSA '96 Meeting Program and Abstracts

Hosted by:

MacCarthy Geophysical Laboratory
 Department of Geology
 University of North Carolina at Chapel Hill

Sunday, October 6

3:00–5:00 pm Northeast Network Operators Meeting
 Room 106 Mitchell Hall, UNC Campus

3:30–5:00 pm Southeast Network Operators Meeting
 Room 07 Mitchell Hall, UNC Campus

5:00–6:00 pm Combined Network Operators Meeting
 Room 106 Mitchell Hall, UNC Campus

6:00–8:00 pmICEBREAKER First Floor Lounge, Mitchell Hall, UNC Campus

sponsored by Nanometrics, Inc., Refraction Technology, Inc., Teledyne Brown Engineering, Digital Technology Associates

Registration will take place from 6:00–7:30

Monday, October 7

(Van leaves for the Friday Center at 8:25, 8:40)

8:30 am Registration, Willow Lounge
 Friday Center

9:00–4:45 pm Technical Sessions
 Seminar Room

(Van leaves for the University Inn at 5:00, 5:15)

(Van leaves for the Friday Center at 6:45, 6:55)

7:00 pmANNUAL BANQUET
 Trillium Room, Friday Center

Wine provided by Nanometrics, Inc., Refraction Technology, Inc., Teledyne Brown Engineering, Digital...

Several propositions of more than passing interest are presented in Tom Jordan's exegetical essay, (“Is the Study of Earthquakes a Basic Science?” by Thomas H. Jordan, Seism. Res. Lett., 68 (2), 259–267, 1997), which was evidently stimulated by his chairmanship of the NRC's Committee on the Science of Earthquakes. Jordan poses the question, perhaps only rhetorically, of whether the study of earthquakes, i.e., seismology, is a basic science. He and I agree that such a study is worthy to have its own discipline as a subgenus of geophysics (and, hence, physics). Given this stand, it might be thought peculiar that Jordan studiously avoids the generic title “seismology,” bestowed in 1862 by the Irish engineer Robert Mallet in his The First Principles of Seismology. Jordan prefers the sobriquet “earthquake science” (perhaps a result of residing in a Department of Earth, Atmospheric, and Planetary Sciences—rather than of Geology and Geophysics). This usage...

NEW SSA HONORARY MEMBERS

The SSA Board of Directors recently elected three former Editors of BSSA to Honorary Membership in the Society: Bruce Bolt, Tom McEvilly, and David Boore. Under the SSA Bylaws, “Honorary Members shall be persons distinguished for their attainments in seismology or related sciences, or for their service to the profession or the society; who shall have been elected to honorary membership by a three-fourths vote of the Board of Directors...”

In notifying the honorees of their election, President Ralph Archuleta cited the Board's wish to recognize their extraordinary service to the science by their long-term dedication and resolve as Editors of the Bulletin of the Seismological Society of America. In addition, President Archuleta cited the very important work that Bruce Bolt has done to explain the science of seismology to non-seismologists.

Bruce Bolt was editor of BSSA from 1965 to 1970; Tom McEvilly served from 1977...

Eduard Berg, a member of SSA since 1963, died March 7, 1997 in Honolulu, Hawai`i, where he had lived for more than 25 years. An internationally known expert in earthquake seismology and volcanology, his passing at age 69 closed a life of exploration, scholarship, and accomplishment.

Ed was born November 9, 1928 in Trier, Germany. He received a Ph.D. in physics from the University of Saarbruecken in 1955. His Ph.D. research was on radio wave propagation in a stratified troposphere, work which would significantly influence his subsequent teaching of theoretical seismology. During the succeeding eight years, Ed conducted geophysical research at the Institute for Scientific Research in Central Africa, in what was then Belgian Congo. From 1959 to 1963, he was head of the Seismology and Volcanology Research Group at that institute. Working in the Congo in the fifties and sixties, Ed was forced to develop a practical common sense...

Robert P. Meyer, Professor of Geophysics at the University of Wisconsin in Madison, died on April 9, 1997 in Punta Gorda, FL. He had been living with leukemia for five years. Meyer, an internationally recognized geophysicist, was well known for his contributions to seismic studies of the Earth's crust and upper mantle and the development of innovative instrumentation.

Bob was born on December 12, 1924, in Milwaukee, Wisconsin. He began his studies at Carleton College but these were interrupted for service in the Army Air Corps as a radar instructor during World War II. He returned to school at the University of Wisconsin in Madison where he obtained a B.S. in physics and a Ph.D. in geophysics. His studies were directed by George P. Woollard, a pioneer in the geophysical study of Earth's structure and Bob's long-time mentor and friend. Woollard encouraged Bob's taste for travel, adventure, and pioneering field...

Stephan Mueller died at the age of 66, only one-and-a-half years after his retirement in 1995 from the Chair of Geophysics and Directorship of the Swiss Seismological Service at the Swiss Federal Institute of Technology (ETH) and from the Chair of Geophysics at the University in Zürich. His death was due to penumonia after an intestinal operation.

Born in Marktredwitz, Bavaria (Germany), he went to school in Passau and Stuttgart. He studied physics at the University of Stuttgart (Diploma in 1957) and electrical engineering at Columbia University in New York (M.Sc. in 1959). During his studies he obtained scholarships at the Technical University in Berlin and at Columbia University. Also at the University of Stuttgart, Stephan came into contact with Wilhelm Hiller, a classical seismologist and head of the State Seismological Service, who aroused Stephan's interest in geophysics. This interest quickly evolved into his major study. While at Columbia, he...

The 92nd Annual Meeting of the Seismological Society of America was held on April 9–11, 1997 at the Hawaiian Regent Hotel, Waikiki Beach, Honolulu, Hawaii. The meeting was hosted by the University of Hawaii at Manoa; Patricia Cooper was the meeting chairperson, and Gerard Fryer and Neil Frazer chaired the program committee. Over 200 presentations were made at the meeting, which had a registration of 250. The meeting venue was comfortable and attractive, and both the poster sessions and the talks were well attended. The annual luncheon featured several notable events. The SSA Medal was awarded to Jim Brune of the University of Nevada at Reno. Bruce Bolt (University of California at Berkeley), David Boore (U.S. Geological Survey) and Tom McEvilly (University of California at Berkeley), all former BSSA editors, were named as honorary members of the SSA. Finally, Steve Wesnousky delivered the presidential address. Local television and newspapers covered...

Citation

The Seismological Society of America Medal has been awarded to those persons whose scientific contributions bolster the overall field of earthquake science and engineering. Previous recipients share many traits—among those is the drive to answer the fundamental questions. Success is measured in the number of times these individuals have answered the ever-present question “Why?” or made the rest of our community search for answers.

This year's recipient, James Neil Brune, is certainly one who has answered many such questions and at the same time forced all of us to look deeper into the nature of our science. Jim's mentors, colleagues and students have universally commented on Jim's deep intuitive approach for addressing fundamental problems. Phrases such as “extraordinary intuitive sense” or “incredible strength of his intuition and the sharpness of his reasoning” or “remarkable physical insight” are used to describe Jim's approach to science. In a nominating letter for...

The following are statements from candidates seeking election to the SSA Board of Directors. Ballots and other election information will be sent to SSA members in the Fall.

KENNETH W. CAMPBELL

EQE International, Inc.

Principal fields: Strong ground motion and seismic hazard evaluation.

I received my Ph.D. in 1977 in Geotechnical Engineering from the School of Engineering and Applied Science, University of California, Los Angeles. My 25 years of professional experience has included both research and consulting. I spent 7 years as a research civil engineer with the US Geological Survey Branch of Geologic Hazards Assessment in Golden, Colorado, where I developed strong-motion attenuation relationships and participated in the development of a US national seismic hazard map. As a consultant with various engineering consulting firms, I have developed seismic design criteria and performed seismic hazard evaluations for nuclear facilities, industrial facilities, lifelines, on-shore and offshore oil and gas facilities and...

March 16–18, 1998 (Monday–Wednesday)
 University Memorial Center, University of Colorado
 Boulder, Colorado, USA

For Current Information:

Via WWW: http://geohazards.cr.usgs.gov/ssa98.html

Email: [email protected]

Important Dates

Abstract Submission Deadline: January 9, 1998

Abstract Withdrawal Deadline: January 31, 1998

Program/Abstracts on WWW: February 14, 1998

Preregistration Deadline: February 21, 1998

MEETING CHAIRS

Kaye M. Shedlock
 USGS
 MS 966
 Box 25046
 Denver, CO 80225
 TEL: 303-273-8571
 FAX: 303-273-8600
 Email: [email protected]

Anne F. Sheehan
 CU/CIRES
 Campus Box 216
 University of Colorado
 Boulder, CO 80309
 TEL: 303-492-4597
 FAX: 303-492-1149
 Email: [email protected]

CALL FOR PAPERS

Abstract Deadline: January 9, 1998

Send Abstracts to: 1998 SSA Program Committee
 c/o Seismological Society of America
 201 Plaza Professional Building
 El Cerrito, CA 94530

To submit an abstract, carefully follow the Instructions for Submitting Annual Meeting Abstracts following this announcement. Instructions for submitting abstracts electronically are available on the SSA homepage (www.seismosoc.org/ssa/).

Abstract Fee: $35 per abstract

Each abstract must be accompanied by the abstract fee. Payment may be made by...

Refraction Technology, Inc. Announces Improved Internet Access!

You can now send Internet e-mail directly to many Ref Tek personnel. Mail addressed to a non-existent mail account for our domain is not returned to the sender but is received by a default account and internally forwarded to the desired recipient.

The old Ref Tek e-mail address ([email protected]) will continue to be available for only a short time. Please use one of the new addresses for all future e-mail.

Ref Tek's FTP site has also moved. Its new location is ftp.reftek.com. The new location includes an “incoming” directory where you can post files. Please limit postings to 5 Mbytes and notify RefTek promptly by e-mail whenever you post something to our site. Ref Tek has also begun work on a Web site. You can view our introductory Web page at www.reftek.com. We will be working on...

The first device designed to measure earthquake-induced ground motion was built in A.D. 132 by Chang Heng in China, and for the next sixteen centuries, studies of earthquakes remained the exclusive domain of seismologists. Not until the latter part of the eighteenth century, when French nobleman Déodat Gratet de Dolomieu reported the first significant field observations of effects from the 1783 earthquake in southern Italy, did geology begin to play a role in earthquake studies. Systematic geological studies of earthquakes and faults did not begin for more than 100 years later in the latter part of the 19th century, when seminal reports such as those by G. K. Gilbert emphasized the connection between surficial features and earthquakes. More than two hundred years have passed since Dolomieu's pioneering descriptions, but only during the past 20 or 30 years has the unique value of earthquake geology been widely recognized and appreciated. The...

This is the first volume of a new two-volume historical catalogue of Mexican earthquakes from pre-Hispanic times through 27 December 1912, by anthropologist Virginia Acosta and seismologist Gerardo Suárez. It is a heavyweight of a volume, which was co-produced by the state-owned publishing house FCE, together with the University of Mexico and the Center for Social Anthropology (CIESAS). Regretfully, I do not know the cost, but certainly this magnificently produced volume is a collector's bargain at any price.

In his foreword, Gerardo Suárez points out that earlier chronological listings of Mexican earthquakes (such as the catalogue of Orozco y Berra, published in 1887) are unreliable and provide at most a sketchy summary of the historical information. The references are often omitted. The result is highly subjective and tinted with dated scientific interpretations. The present work quotes all original sources in full “at the risk of providing a long and unwieldy...

AGU History of Geophysics Series

Shocks and Rocks: Seismology in the Plate Tectonics Revolution by Jack Oliver has recently been published by the American Geophysical Union (AGU). It is Volume 6 in the History of Geophysics Series. This book presents the story of seismology and the great plate tectonics revolution of the 1960s. Ideas from the nineteenth century that formed the revolution up to ideas of today that have built upon the revolution are traced. Jack Oliver wrote this book as a participant of the revolution and not as a historian. His perspective shows the elaborate role seismology had to play in the plate tectonics revolution. Shocks and Rocks “describes just how a science works when things are going well, in the hope of accelerating the pace toward great discoveries of the future.”

This book was reviewed in SRL (Volume 68, Number 3, May/June 1997, page 449).

It can be...

Dates: October 5-8, 1997

Hosted by: Carleton University
 Geological Survey of Canada
 The Ottawa-Carleton Earthquake Engineering Research Centre

Convenor: Gail Atkinson, Carleton University (613) 520-2600 Ext. 1399

Abstract Deadline: Friday August 29, 1997

Presentations (posters or 15 minute talks) dealing with all aspects of seismicity, historical earthquakes, tectonics, seismic hazards, real-time seismology, earthquake source studies, induced earthquakes, wave propagation and earth models, public relations concerning earthquakes and earthquake engineering are cordially invited, especially those with applications to eastern North America. Abstracts for all presentations will be published in Seismological Research Letters.

Special Theme Sessions:

Seismic Hazard Assessment in Intraplate North America
 Seismicity Related to Industrial Activity
 Earthquakes of the Charlevoix-Saguenay Region
 Tectonics of the Lithosphere in Eastern North America
 What Earthquake Engineers Do (and Want) in Eastern North America
 Seismologists and Earthquake Emergencies

Field Trip: Oct 5, 1997, Tour of Paleozoic fault structures of the Ottawa-Bonnechere Graben

Housing: Market Square Inn, 350 Dalhousie St., Ottawa, Ont, K1N...

1997

September 3–9. Scientific Assembly of the International Association of Geodesy, Rio de Janeiro, Brazil.

C. Tscherning, International Association of Geodesy, Central Bureau, c/o Department of Geophysics, Juliane Maries vej 30, DK-2100 Copenhagen Oe., Denmark, telephone +45-35320600; fax +45-35365357; e-mail [email protected], URL http://www.gfy,ku.dk/~iag/

September 8–12. Intraplate Magmatism and Tectonics of Southern Africa, Harare, Zimbabwe.

Sponsors include the Geological Society of Zimbabwe and the Department of Geology at the University of Zimbabwe. P. Dirks, Geological Society of Zimbabwe, Intraplate Magmatism and Tectonics of Southern Africa Conference, The Conference Secretary, P.O. Box CY1719, Causeway, Harare, Zimbabwe, e-mail [email protected]

September 22–27. Seminar on Assessment and Mitigation of Seismic Risk in the Central American Area, Universidad Centroamericana “Jose Simeon Canas,” San Salvador, El Salvador, Central America.

The seminar is organized by the Universidad Centroamericana “Jose Simeon Canas” in San Salvador and is sponsored by the Commission of the...