搜尋結果
On 11 March 2011, at 14:46 JST (05:46 UTC), a Mw 9.0–9.1 undersea megathrust earthquake occurred in the Pacific Ocean, 72 km (45 mi) east of the Oshika Peninsula of the Tōhoku region. It lasted approximately six minutes and caused a tsunami. It is sometimes known in Japan as the "Great East Japan Earthquake" (東日本大震災, Higashi ...
On 26 December 2004, at 07:58:53 local time (), a major earthquake with a magnitude of 9.2–9.3 M w struck with an epicentre off the west coast of northern Sumatra, Indonesia.The undersea megathrust earthquake, known by the scientific community as the Sumatra–Andaman earthquake, was caused by a rupture along the fault between the Burma Plate and the Indian Plate, and reached a Mercalli ...
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Prior to the development of the magnitude scale, the only measure of an earthquake's strength or "size" was a subjective assessment of the intensity of shaking observed near the epicenter of the earthquake, categorized by various seismic intensity scales such as the Rossi-Forel scale. ("Size" is used in the sense of the quantity of energy released,...
The Richter scale was defined in 1935 for particular circumstances and instruments; the particular circumstances refer to it being defined for Southern California and "implicitly incorporates the attenuative properties of Southern California crust and mantle." The particular instrument used would become saturated by strong earthquakes and unable to...
The Richter magnitude of an earthquake is determined from the logarithm of the amplitude of waves recorded by seismographs (adjustments are included to compensate for the variation in the distance between the various seismographs and the epicenterof the earthquake). The original formula is: 1. M L = log 10 A − log 10 A 0 ( δ ) = log 10 [ A / ...
These formulae for Richter magnitude ML are alternatives to using Richter correlation tables based on Richter standard seismic event (M L = 0 {\displaystyle M_{\mathrm {L} }=0} , A = 0.001 m m {\displaystyle A=0.001\mathrm {mm} } , D = 100 k m {\displaystyle D=100\mathrm {km} } ). Below, Δ {\displaystyle \textstyle \Delta } is the epicentral distan...
Seismic Monitor – IRIS ConsortiumPerspective: a graphical comparison of earthquake energy release – Pacific Tsunami Warning CenterThe Ring of Fire (also known as the Pacific Ring of Fire, the Rim of Fire, the Girdle of Fire or the Circum-Pacific belt) [note 1] is a tectonic belt of volcanoes and earthquakes. It is about 40,000 km (25,000 mi) long [1] and up to about 500 km (310 mi) wide, [2] and surrounds most of the Pacific Ocean. The Ring of Fire contains between 750 ...
An earthquake is the shaking of the surface of Earth resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes may also be referred to as quakes, tremors, or temblors. The word tremor is also used for non-earthquake seismic rumbling . In its most general sense, an earthquake is any seismic event ...
The area within 100km radius of New York City has an intermediate level of seismic activity, more than what is observed in central New York State. [11] It is not as seismically active as California which is located at a transform plate boundary, but large and damaging earthquakes do occur.
Casualties of the September 11 attacks. The September 11 attacks of 2001 were the deadliest terrorist attacks in human history, causing the deaths of 2,996 people, including 2,977 victims and 19 hijackers who committed murder–suicide. Thousands [a] more were injured, [3] [4] and long-term health effects have arisen as a consequence of the ...
