Initiation process of earthquakes and its implications for seismic hazard reduction strategy.

For the average citizen and the public, "earthquake prediction" means "short-term prediction," a prediction of a specific earthquake on a relatively short time scale. Such prediction must specify the time, place, and magnitude of the earthquake in question with sufficiently high reliability. For this type of prediction, one must rely on some short-term precursors. Examinations of strain changes just before large earthquakes suggest that consistent detection of such precursory strain changes cannot be expected. Other precursory phenomena such as foreshocks and nonseismological anomalies do not occur consistently either. Thus, reliable short-term prediction would be very difficult. Although short-term predictions with large uncertainties could be useful for some areas if their social and economic environments can tolerate false alarms, such predictions would be impractical for most modern industrialized cities. A strategy for effective seismic hazard reduction is to take full advantage of the recent technical advancements in seismology, computers, and communication. In highly industrialized communities, rapid earthquake information is critically important for emergency services agencies, utilities, communications, financial companies, and media to make quick reports and damage estimates and to determine where emergency response is most needed. Long-term forecast, or prognosis, of earthquakes is important for development of realistic building codes, retrofitting existing structures, and land-use planning, but the distinction between short-term and long-term predictions needs to be clearly communicated to the public to avoid misunderstanding.

SeismicWaveTool: Continuous and discrete wavelet analysis and filtering for multichannel seismic data

A MATLAB-based computer code has been developed for the simultaneous wavelet analysis and filtering of multichannel seismic data. The considered time–frequency transforms include the continuous wavelet transform, the discrete wavelet transform and the discrete wavelet packet transform. The developed approaches provide a fast and precise time–frequency examination of the seismograms at different frequency bands. Moreover, filtering methods for noise, transients or even baseline removal, are implemented. The primary motivation is to support seismologists with a user-friendly and fast program for the wavelet analysis, providing practical and understandable results.

John Winthrop's proposal respecting electrical globes and jars, ca. 1758

In this proposal, John Winthrop explains the need to replace damaged "electric globes" used in the College's collection of scientific apparatus. He states that Benjamin Franklin, at the time residing in London, was willing to seek replacement globes for the College's collection. Winthrop then proceeds to assert that the College should acquire "square bottles, of a moderate size, fitted in a wooden box, like what they call case bottles for spirits" instead of the large jars included in the scientific apparatus, because those jars cracked frequently.

Seismicity of the earth and associated phenomena,

Mode of access: Internet.

Evaluation of seismometer wave gage and comparative analysis of wave data at Yaquina and Coquille Bays, Oregon /

"September 1985."

Annual report of the meteorological and the seismological observations made at the International Latitude Observatory of Mizusawa.

Mode of access: Internet.

Geophysical investigation, Prado Dam and Mentone Damsite, California /

"June 1975."

Bulletin of the Seismological Society of America.

Energy research abstracts

Seismic signal processing via the ILLIAC IV computer,

Bibliography: p. [12]

Geological-seismological evaluation of earthquake hazards at Franklin Falls Damsite, New Hampshire /

Abstract.

Seismic source functions for closely-spaced simultaneous nuclear detonations /

"February 1973."

Technical report, characterization of ground motions during the Northridge earthquake of January 17, 1994 /

"Program to reduce the earthquake hazards of steel moment frame structures"--Cover.

Strong motion earthquake accelerograms : digitized and plotted data /

"A report on research conducted under a grant from the National Science Foundation."

National Earthquake Hazards Reduction Program : five-year plan for 1989-1993.

"Federal Emergency Management Agency; National Bureau of Standards; National Science Foundation; United States Geological Survey."

Research accomplishments, 1986-1994 /

"September, 1994."