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(1) Some people believe Japan has more earthquakes than Taiwan. Not True.
(a) Hazard Mapping Images and Data: USGS National Seismic Hazard Maps, Data,
and Documentation. United States Geological Survey (USGS), U.S. Department
of the Interior, undated.
http://earthquake.usgs.gov/hazards/products/
Check the last item of the text: The Global Seismic Hazard Assessment
Program (GSHAP), whose caption reads, in part, "The GSHAP project terminated
in 1999" (no updates since, that is).
The map is not big (or detailed) enough to differentiate colors--and thus,
gradings--of Taiwan and Japan. See next for the same map.
On its own, USGS updates earthquakes within and without US in the home page:
http://earthquake.usgs.gov/
(b) Giardini D, Grunthal G, Shedlock KM and Zhang P, The GSHAP Global
Seismic Hazard Map. Annali di Geofisica, 42: 1225-1230
(December 1999).
http://www.earth-prints.org/bitstream/2122/1396/1/18%20giardini.pdf
Check out the map in p. 1226 AND paragraph 1 of p. 1227.
(2) The following will explain. It is not academic, but science is not
necessarily fun. Still the subject will broaden your horizon.
(a) Plate tectonics
http://en.wikipedia.org/wiki/Plate_tectonics
is a great astarting point.
(i) Map 1 is "the tectonic plates of the world."
(ii) Map 2 has the caption: "Detailed map showing the tectonic plates with
their movement vectors." The operative word is "detailed."
Taiwan has all three types* of plate boundaries/movements.
* Marked by purple, red and green, which represents
convergent boundaries, divergent boundaries and transform boundaries (see
Section 3 "Types of plate boundaries" in Wikipedia).
Japan has only one type: convergent boundaries, which includes subduction
zones (and the other).
(b) Pacific Ring of Fire
http://en.wikipedia.org/wiki/Pacific_Ring_of_Fire
(It is sometimes called the circum-Pacific seismic belt 環太平洋地震帶)
Quote:
"About 90% of the world's earthquakes and 80% of the world's largest
earthquakes occur along the Ring of Fire. The next most seismic region (5–6
% of earthquakes and 17% of the world's largest earthquakes) is the Alpide
belt, which extends from Java to Sumatra through the Himalayas, the
Mediterranean, and out into the Atlantic. The Mid-Atlantic Ridge is the
third most prominent earthquake belt.
(c) Paragraph 1 in each of
(i) Seismic hazard
http://en.wikipedia.org/wiki/Seismic_hazard
(ii) Seismic Risk
http://en.wikipedia.org/wiki/Seismic_risk
("A building located in a region of high seismic hazard is at lower risk if
it is built to sound seismic engineering principles. On the other hand, a
building located in a region with a history of minor seismicity, in a brick
building located on fill subject to liquifaction can be as high or higher
risk.")
The "fill" as a noun denotes a landfill.
(3) Taiwan Earthquakes. Risk Management Solutions, Inc. Newark, California,
undated.
http://www.rms.com/publications/Taiwan_EQ.pdf
("Taiwan sits on an extremely active tectonic region, with seismicity and
rates of crustal motion among the
highest in the world. The country is also home to a dense population and
numerous manufacturing operations.")
921 earthquake
http://en.wikipedia.org/wiki/921_earthquake
(a magnitude 7.6 earthquake which occurred at 1:47 [a.m.] local time on
Sept. 21, 1999 at Chichi 南投縣集集鎮)
(4) Lew M et al, The significance of the 21 September 1999 Chi-Chi
earthquake, Taiwan, for tall buildings. The Structural Design of Tall
Buildings, 9: 67-72 (2000).
http://www3.interscience.wiley.com/journal/72001488/abstract?CRETRY=1&SRETRY=0
(5) No place on earth is immune from earthquake.
(1) Earthquake
http://en.wikipedia.org/wiki/Earthquake
Whose section 1.2 with heading "Earthquakes away from plate boundaries"
states that "many earthquakes occur away from the plate boundary and are
related to strains developed within the broader zone of deformation caused
by major irregularities in the fault trace * * * All tectonic plates have
internal stress fields caused by their interactions with neighbouring plates
and sedimentary loading or unloading (e.g. deglaciation). These stresses
may be sufficient to cause failure along existing fault planes, giving rise
to intraplate earthquakes."
(2) I live in Massachusetts. Collective recollection is there is no
earthquake in New England. The truth is opposite--even a handful of major
ones, which occurred centuries ago when few people inhabited the region (
compare earthquake risk v. hazard). See
Earthquakes. The Northeast States Emergency Consortium (NESEC), undated.
http://www.nesec.org/hazards/earthquakes.cfm
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发表于 4-18-2010 16:49:21
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