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Report
#1: Earthquake Information For the World:
Understanding
Earthquake Hazards Around The World
An essential
role of the Federal Government is to minimize loss of life and property
that results from natural disasters such as earthquakes. The U.S.
Geological Survey, through its National Earthquake Information Center,
helps fulfill this responsibility. Since 1973, the U.S. Geological
Survey (USGS) has provided up-to-date earthquake information to
scientists, government agencies, universities, private companies,
and the general public.
This information
includes determinations of the locations and severity of seismic
events in the United States and throughout the world, including
the rapid analysis of significant earthquakes on a 24-hour basis.
Seismologists around the world use this information to increase
their understanding of earthquakes and to better evaluate earthquake
hazards
The USGS National
Earthquake Information Center (NEIC) in Golden, Colorado, operates
a 24-hour-a-day Earthquake Early Alerting Service. This service
rapidly and accurately determines the location and magnitude of
significant earthquakes throughout the world. The NEIC immediately
sends this information to key civil defense and public safety agencies,
including railroads, powerplants, and pipeline companies, and Federal
and State emergency service agencies.
The information
also goes to National and international news media, to scientific
agencies (including groups involved in aftershock studies), and
to private citizens who request information. The facts about a damaging
earthquake abroad are also relayed to staffs of the American Embassies
and consulates in the affected countries, and to the United Nations
Department of Humanitarian Affairs in Geneva, Switzerland. The NEIC
issues rapid reports for earthquakes of magnitude 4.5 or greater
in the United States, 6.5 or greater anywhere in the world, and
other earthquakes of lesser magnitude that are potentially damaging.
The NEIC relies
on the cooperation of many seismic- reporting networks throughout
the world to gather data. More than 3,000 seismic stations report
data to the NEIC. Of the many millions of earthquakes estimated
to occur each year, the NEIC staff presently locates and publishes
information for approximately 20,000 events. The NEIC and its cooperators
have located more than a quarter million earthquakes since 1973.
The NEIC is open to the public and provides daily tours to both
individuals and groups. At the facility in Golden, Colorado, USGS/NEIC
spokesman Waverly Person explains earthquakes to the media, students,
and other visitors from around the world. NEIC Products and Services
·Quick Epicenter Determinations: Updated daily, this is a preliminary
list of earthquakes available for computer access by modem and over
the Internet.
This list
includes about 350 events. ·Preliminary Determination of Epicenters:
Lists parameters for all earthquakes located by the NEIC. Weekly
and monthly bulletins are published electronically on the World
Wide Web. ·Earthquake Data Report: Published electronically on the
World Wide Web. This provides detailed information on about 1,600
events each month. Information is intended for use by seismologists
who provide data to the NEIC. ·State, national, and global seismicity
maps: Earthquake data are also made available on CD-ROM's.
Earthquake
Information Line: (303-273-8516) offers, on a 24-hour basis,
a recorded message about earthquakes throughout the world with magnitudes
5.5 or greater,and earthquakes that are felt and (or) cause damage
in the United States. The line is updated twice daily or whenever
a significant earthquake occurs. Through the NEIC, the USGS continues
to develop new technologies to monitor, analyze, communicate, and
respond to earthquake hazards. In this role, the USGS/NEIC during
the past quarter century has become the global leader in providing
timely, reliable earthquake information to the citizens of the United
States and to people with interest in earthquakes throughout the
world. Cooperators The USGS/NEIC cooperates with institutions and
observatories in about 80 countries.
By Waverly
J. Person, Madeleine D. Zirbes, and William M. Brown III For more
information contact: National Earthquake Information Center (303)-273-8500
U.S. Geological Survey Denver Federal Center Mail Stop 967 Denver,
CO 80225-0046 USA http://wwwneic.cr.usgs.gov U.S. Geological Survey
Fact Sheet 125-97 1997 - U.S. DEPARTMENT OF THE INTERIOR.
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Report
#2: SPECIAL REPORT: An Earthquake Interview Update
With Geologist: David Schwartz of The office of the US Geologic
Survey Menlo Park, California
Q: How accurately can you predict earthquakes around
the world?
A: There
is no way to predict the frequency of global earthquakes.
Q:
What about the Pacific Rim Countries?
A: The
risk and hazard is higher for the Bay Area and Southern California.
Risk for the Pacific Northwest is a little lower, because the faults
are younger, more shallow and less active. The more or greater the
number of sources for a quake, the higher the probability or risk
will be, because they determine how often the fault will move. The
risk factor for the San Francisco Bay area is 70% for a major quake
by 2030.
Q:
Do earthquakes relieve the stress on a fault?
A: Sometimes.
The 1906 San Francisco quake relieved the stress so that there has
not been a major earthquake in San Francisco since. The stress does
built back up again. And sometimes release of stress can push an
adjacent fault closer to failure. Studying a geologic fact sheet
of your area can show you the risk factor for that area.
Q:
People think that their area will not be hit-or that if they are
on bedrock they are safe. Is that true?
A: There
is almost no escape in high risk areas. A major earthquake in the
Bay Area or Southern California would be felt by everyone in that
area. Just as the Loma Prieta and Northridge quakes were felt and
did great damage far from the epicenter--the Loma Prieta quake was
on a fault we didn't even know about!
Q: Is there any chance that California can fall into the ocean during
a major earthquake?
A:
None. The tectonic plates run horizontally, not vertically.
Q:
Why is the damage so much greater in other countries?
A: In
other countries, the local contractors know, but do not often follow,
the building codes. Unreinforced adobe structures and tile roofs
will fall-wherever they are-in a major earthquake!
Q: So, reinforcing and securing can actually can save your life,
home and valuables in a major quake?
A: Yes.
It is important to educate people now. There's no time to wait!
Inteview
conducted by Sharon D. Hart February, 2002
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