terdahsyat Indonesian nation has ever experienced. After two years since the earthquake and
the tsunami struck Aceh, North Sumatra, South East Asia, South Asia, and eastern Africa,
experts have now been getting a lot of new data and analysis that produces more evaluation
accurate about this global disaster. Here is a summary of data, analysis, and interpretation of new
is based on the many recent publications (Wikipedia, New Scientist, NASA, Science,
etc.). Hopefully useful.
This earthquake occurred on December 26, 2004 at 00:58:53 GMT or 07:58:53 local time (GMT).
Location of the epicenter is on the west coast of Sumatra to the north of Simeulue Island in
coordinates 3316 ° N, 95,854 ° E (3 ° 19'N 95 ° 51.24 'E), about 160 km west of Sumatra. The epicenter was
at a depth of 30 km below the mean sea level (initially reported at a depth of 10 km).
This earthquake was reported magnitude (moment magnitude) 9.0 MW. In February 2005
magnitude is corrected to 9.3. (McKee, 2005: "Power of tsunami earthquake heavily
underestimated. "New Scientist - February 9, 2005, p.. 5). study the most recent in 2006
call this earthquake has the power MW 9.1 - 9.3. Dr. Hiroo Kanamori, a seismologist famous
from the California Institute of Technology said the quake had a magnitude of MW = 9.2. (EERI
Publication 2006-06, p.. 14). In addition, especially in Aceh and northern Sumatra, the quake was felt
so far: Bangladesh, India, Malaysia, Myanmar, Thailand, Singapore and Maldives.
This earthquake magnitude earthquake in addition to occupying the position of second largest after the 1960 Chile earthquake
which reached 9.5 on the Richter Scale (the end of the Richter Scale was there), Aceh earthquake was ranked
first as an earthquake with time (duration) of the longest penyesaran ie, up to 500-600
seconds (10 minutes). And, this earthquake is big enough to make the whole earth shook with the ball
vibration amplitude on top of one cm (Walton, 2005 "Scientists: Sumatra Quake Longest ever recorded."
CNN - May 20, 2005). The quake also triggered other earthquakes around the world so far
Alaska (West, Sanches, McNutt, 2005: "Periodically Triggered Seismicity at Mount Wrangell, Alaska,
after the Sumatra Earthquake. "Science. Vol. 308, No. 5725, p.. 1144-1146, May 20, 2005).
Aceh earthquake has caused a series of destructive tsunami beaches in Aceh, Sumatra
North, Sri Lanka, India, Thailand and other countries with high waves up to 30
meter causing severe damage and destruction and death as far as the coast
eastern Africa. The death toll from the tsunami is reported to occur at Rooi Els in South Africa at a distance
8,000 km from the epicenter. Preliminary estimates for the tsunami victims around the world is over
275,000, not including the thousands of victims lost. However, recent analysis of total mentions
tsunami victims is 229. 866 people (186,983 dead and 42,883 missing) (UN Office for the
Tsunami Recovery, 2006). Earthquake and tsunami disaster is referred to as the worst
in modern history. This disaster has also invited the sympathy of many countries in the world, proved
with the aid commitments amounting to a total of more than 7.0 billion dollars in the United States (Wikipedia, 2006).
Earthquake Characteristics December 26, 2004
The quake was also remarkable in its geographical coverage. An estimated 1200 km along the fault lines
shifted about 15 feet along the subduction zone where the Indian Ocean plate slipping
Burma under the continental plate (the Eurasian Plate). The shift did not occur sekonyongkonyong fault but in two phases over several minutes. Acoustic data and the seismograph showed
that the first phase includes the formation of debris zone along the 400 km wide and 100 km, padakedalaman 30 km below the seabed. This is the longest ever produced ruins of the earthquake.
Ruins running lengthwise with a speed of 2.8 km / sec or 10,000 km / hour. Debris began
occurred off the coast of Aceh and proceeding toward the northwest for 100 seconds before debris
turn clockwise to the north toward the islands of Andaman and Nicobar Islands. When the deflection
, the debris stopped momentarily for 100 seconds. The second phase of the ruins to the north of this
runs with a lower speed that is 2.1 km / sec or 7600 km / hour. Then the debris continues
continue north for five minutes until the plate boundary where it turns up penyesaran
become penyesaran flat. This change reduces the rate of mass transfer in the ocean
thereby reducing the amplitude of the tsunami that occurred in the northern Indian Ocean (Kostel and
Tobin, 2005: "The Sound of a Distant Rumble: Researchers Track Underwater Noise Generated by
December 26 Earthquake. "- Lamont-Doherty Earth Observatory, July 20, 2005; Wikipedia, 2006).
Aftershocks with magnitudes up to 6.6 continue to occur in this region (offshore islands
Andaman and Nicobar Islands) until four months after a major earthquake. Another major earthquake that occurred in
around the island of Nias on March 28, 2005 with magnitude 8.7 (MarketWatch, 2005 "8.7 Quake jars
Sumatra, at least 300 dead. "Investors.com.) Cause debate among scholars: whether the
This Aftershock earthquake December 26, 2004 or "triggered earthquake" (earthquake caused
by a previous earthquake) (McKernon, 2005, Science and Engineering at The University of Edinburgh
School of Geosciences). Nias earthquake occurred on the same fault line with the location of the earthquake 26
December 2004.
Large earthquake in Aceh comes just three days after a major earthquake magnitude 8.1
hit an uninhabited region west of the Auckland Islands (New Zealand-owned)
and to the north of Macquarie Island (Australian owned) in Antarctica. This unusual
because based on statistics for this earthquake with a strength above 8.0 occurred only once
in a year (USGS Earthquake Hazards Program: FAQ; Skinner et al., 2004, Dynamic Earth, of things.
359), but the earthquake magnitude> 8.0 are separated by only three days. Some seismologists
speculate about the relationship Antarctic earthquakes and earthquake in Aceh this. Earthquake Antarctica may
has acted as a catalyst because the second earthquake Aceh earthquake occurred respectively in
tip of southern and northern sides of the Indo-Australian Plate. However, the USGS said there was no evidence
convinced that these two earthquakes are related. Clearly, the Aceh earthquake occurred exactly one year
(Until the hour was the same incident) after a 6.6 magnitude earthquake that killed 30,000 people in
city of Bam, Iran on December 26, 2003 (Wikipedia, 2006). What is unique too, is that the earthquake
Aceh (magnitude 9.3) occurred the day after Christmas Day (December 25, 2004) and the Nias earthquake
(Magnitude 8.7) occurred the day after Easter Day (March 27, 2005).
Second quake (earthquake in Aceh and Nias earthquake) have enabled the volcano-volcanoes surrounding
Sunda volcanic arc on the path in the Barisan Mountains. Gunung Leuser in Aceh is activated by
Aceh earthquake, as well as the eruption of Mount Talang in April 2005. Nias Earthquake turn for a moment
ancient Toba caldera, so we know that the ancient caldera is not yet dead, only sleeping
length (Rinaldo, 2005: "Thousands Flee as Indonesian volcano spews into life." Hindustan Times, 12
April 12, 2005; Johnston, 2005: "Indonesian Volcanoes Erupt; Thousands Evacuated", VOA News).
What is the strength of this earthquake December 26, 2006? The total energy released is about 3:35
exajoules (3.35 × 1018 joules). This is equivalent to more than 930 tera (10 ^ 12) watt-hour
or 0.8 gigatons of TNT, or equal to all energy used in the United States during
11 days. The earthquake has also resulted in oscillations of the Earth's surface as high as 20-30 cm, the same
with the rising tide caused by the gravitational effects of the Sun and the Moon. Earthquake shock waves felt in
the whole face of the planet Earth as far as Oklahoma in the U.S. which recorded as high as 3 mm of vertical motion (Staff Writer, "Earthquake felt in Oklahoma, too." MuskogeePhoenix.com. December 28, 2004).
The entire surface of the Earth is believed to have been lifted to a height of 1 cm.
Mass shift in the Earth's crust and that such a large energy loss due to this gempan been
slightly altering the Earth's rotation period. Exact value has not been determined, but models
made shows that this earthquake had shortened the length of day as much as 2.68 microseconds
or a billionth of a length of one day due to the reduced kepepatan (oblateness) spherical Earth (CookAnderson and Beasley: "NASA Details Earthquake Effects on the Earth." NASA press release,
January 10, 2005). The earthquake has also caused the Earth slightly staggered (motion "wobble" - such as
drunken swordsman) on its axis trending 145 ° east (Schechner, 2004, "Earthquakes vs. the Earth's
Rotation "Slate. December 27, 2004) or staggered up to 5 or 6 cm (Staff Writer, 2004" Italian
Scientists say Asian quakes cause Earth's axis shifted. "Xinhua said. December 29, 2004). However, because
effects of tidal motion due to gravity on the Moon always add as many as 15 microseconds long
each year, then the effects due to changes in motion and the period of rotation of the Earth by earthquake in Aceh soon
disappeared.
As a result of the more spectacular emerged locally. There is a movement horizontally along 10
meters and 4-5 meters vertically along the fault lines caused by this earthquake. Early speculation
mentioned that the small islands in the southwest of Sumatra, who plays on the plate
Burma has been moving toward the southwest as far as 20-36 meters. However, based on data
more accurate, issued a month after the earthquake, showed that the movement was only 20 cm
(Staff Writer. "Quake moved Sumatra by only 20 centimeters: Danish Scientists", Agence France
Presse, January 31, 2005). Because of this vertical movement is also lateral (oblique), then there is the
beaches are submerged under the sea. Andaman-Nicobar Islands have been shifted to
southwest as far as 1.25 meters and has sunk nearly 1 meter (Bagla, 2005, "After the Earth
Moved ", Science Now, January 28, 2005).
In February 2005, the Royal Navy research vessel HMS Scott conducted a survey on the seabed in
around the earthquake zone, the sea depth varies from 1,000 m - 5,000 m in the west
Sumatra. The survey, carried out by using high-resolution, multi-beam sonar system is
indicates that the earthquake has caused major changes topograpfi seabed. Activity
tectonics along the geologic time in this section has made the ridge fault ride / factoring (thrust
ridges) as high as 1500 meters, which collapsed in several places during the earthquake generating
avalanche area of several square kilometers. An avalanche region consists of blocks of rocks observed
along the 2 km-high 100 yards. The power of water displaced by changes in bottom topography
This sea has been dragging the block of rock weighing millions of tons is 10 km. Ocean trench width
few km line disclosed in this earthquake (Knight, 2005: "The Asian tsunami seabed Pictured with
sonar "New Scientist - February 10, 2005).
Characteristics of Tsunami December 26, 2004
An earthquake has lifted the sea floor a few feet, moving as much sea water
about 30 km3 triggering devastating tsunami waves. Tsunami waves were not
derived from the epicenter and the point spread radially around the Indian Ocean as
wrongly portrayed in some cartoons, but the wave is spread radially
out of the ruins along the 1200 km (not from "point source" but of "line source").
This has led to a wave continued to spread widely, it is observed until it reaches the Arctic,
Chile, and Mexico. Rising sea floor has been reduced "space of accommodation" of the Indian Ocean
and has led to a permanent increase gloabal sea level (eustasy) by 0.1 mm (Bilham,
2005 "A Flying Start, Then a Slow Slip." Science. Vol. 308, No. 5725, p.. 1126-1127. May 20, 2005). Coincidentally, at the time of the tsunami December 26, 2004, two satellite passed over
Indian Ocean (satellite Topex / Poseidon and Jason satellites 1) (Staff Writer, "NASA / French Satellite
Data Reveal New Details of Tsunami. "Jet Propulsion Laboratory-JPL/NASA, January 11, 2005).
Both of these satellites carry radars that can accurately measure sea surface height in
middle of the ocean. Anomalous height of 50 cm measured. Both satellite measurements are
is an extremely valuable data for understanding the earthquake and the tsunami it generates.
Unlike data from tide gauges (tide gauge) mounted in the coastal areas,
measurements of water levels on the high seas by the satellite can be used to calculate
parameter2 tsunami generation by earthquakes without the need correction due to close efek2
beach (Wikipedia, 2006).
Radar on satellites were recorded tsunami wave heights in the middle of December 26, 2004
the ocean is a maximum of 60 cm at two hours after the quake. This is the first time
tsunami from satellite observations made, it was by accident. However, this observation does not
can be used for the purposes of tsunami early warning for the presence of two satellites above
Crossed the Indian Ocean was not for the purposes of tsunami observations, also takes
several hours to analyze the resulting data.
What is the strength of 26 December 2004 tsunami that? The total tsunami energy is equivalent to
about five megatons of TNT (20 -10 maps rank 15-joules). This is more than twice the total explosive energy
used during World War II (including the two atomic bombs). In many places, the wave
the tsunami reached a height of 24 meters to 30 meters when it struck the coast and into the direction
mainland as far as two miles depending on the topography of the coast (Pearce and Holmes, 2005:
"Tsunami: The Impact Will last for Decades" New Scientist - January 15, 2005).
Since the fault line along the 1200 km have been crippled this earthquake trending nearly north-south,
greatest strength of the tsunami waves on west-east direction. Bangladesh at the northern fault
tsunami affected relatively weakly, compared with a more powerful tsunami strike
Somalia on the west fault, even though Somalia is located farther from the earthquake source. Tsunami
began to attack the coasts around the northern Indian Ocean within 15 minutes
up to 7 hours (Time travel map: Tsunami Laboratory, Novosibirsk, Russia; Time travel map: Active
Fault Research Center: National Institute of Advanced Industrial Science and Technology, Japan).
Tsunami-stricken Aceh and Sumatra is very fast because it is located near fault lines and the rate of
ruins in the segment of fault lines in this region occurs very fast (10,000 miles / hour). Thailand,
although also located near the epicenter, the tsunami attacked two hours later because
debris in the Andaman Sea region occurred more slowly than in the sector of Indonesia.
Tsunamis measured up to the Antarctic by tidal gauges at Japan's research base
Antarctica (Japan's Syowa Base) which records the oscillations of sea level rise up to 1 meter and
This chaos lasted until a few days after the earthquake ("Indian Ocean Tsunami" at
Syowa Station, Antarctica, Hydrographic and Oceanographic Department. Japan Coast Guard). Energy
tsunami was released to the Pacific Ocean produces a wave height anomalies 20-40
cm along the west coast of North America and South America (Indian Ocean Tsunami of 26
December, 2004. West Coast / Alaska Tsunami Warning Center (USGS). December 31, 2004) and in
some places to a height of 2.6 meters on the coast Manzanillo, Mexico. Experts
estimates that the MOR (mid-oceanic ridge) has played a role in focusing and
directs the tsunami in the far jangakauan (Carey, 2005: "Tsunami Waves Channeled
Around the Globe in 2004 Disaster "LiveScience-August 25, 2005).
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