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|mapsize = |date = |origintime = 08:19 UTC |duration = 185 seconds 〔 |magnitude = 7.7 Mw 〔〔 |depth = 〔 |location = 〔 |type = Thrust 〔〔 |countries affected = Java Island, Indonesia |damage = $44.7 million 〔 |intensity = IV (''Light'') 〔〔 |PGA = |landslide = |foreshocks = |aftershocks = 6.0 Mw July 17 at 09:13 6.1 Mw July 17 at 15:45 〔 |casualties = 9,299 injured 〔 }} The 2006 Pangandaran earthquake and tsunami occurred on July 17 at along a subduction zone off the coast of west and central Java, a large and densely populated island in the Indonesian archipelago. The shock had a moment magnitude of 7.7 and a maximum perceived intensity of IV (''Light'') in Jakarta, the capital and largest city of Indonesia. There were no direct effects of the earthquake's shaking due to its light to moderate intensity, and the large loss of life from the event was due to the resulting tsunami, which inundated a portion of the Java coast that had been unaffected by the earlier 2004 Indian Ocean earthquake and tsunami that was off the coast of Sumatra. The July 2006 earthquake was also centered in the Indian Ocean, from the coast of Java, and had a duration of more than three minutes. An abnormally slow rupture at the Sunda Trench and a tsunami that was unusually strong relative to the size of the earthquake were both factors that led to it being categorized as a tsunami earthquake. Several thousand kilometers to the southeast, surges of several meters were observed in northwestern Australia, but in Java the tsunami runups (height above normal sea level) were typically and resulted in the deaths of more than 600 people. Other factors may have contributed to exceptionally high peak runups of on the small and mostly uninhabited island of Nusa Kambangan, just to the east of the resort town of Pangandaran, where damage was heavy and a large loss of life occurred. Since the shock was felt with only moderate intensity well inland, and even less so at the shore, the surge arrived with little or no warning. Other factors contributed to the tsunami being largely undetected until it was too late and, although a tsunami watch was posted by an American tsunami warning center and a Japanese meteorological center, no information was delivered to people at the coast. ==Tectonic setting== The island of Java is the most densely populated island on earth, and is vulnerable to both large earthquakes and volcanic eruptions, due to its location near the Sunda Trench, a convergent plate boundary where the Australian tectonic plate is subducting beneath Indonesia. Three great earthquakes occurred in the span of three years to the northwest on the Sumatra portion of the trench. The 2004 M9.15 Sumatra–Andaman, the 2005 M8.7 Nias–Simeulue, and the 2007 M8.4 Mentawai earthquakes produced the largest release of elastic strain energy since the 1957/1964 series of shocks on the Aleutian/Alaska trench. The southeastern (Java) portion of the Sunda Trench extends from the Sunda Strait in the west to Bali Basin in the east. The convergence of relatively old oceanic crust is occurring at a rate of per year in the west portion and per year in the east, and the dip of the Benioff Zone (the angle of the zone of seismicity that defines the down-going slab at a convergent boundary) is around 50° and extends to a depth of approximately . Historical events that occurred before seismometers were operating in the region were the large to very large events of 1840, 1867, and 1875, but unlike the northwestern Sumatra segment, no megathrust earthquake has occurred on the Java segment of the Sunda Trench in the last 300 years. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「2006 Pangandaran earthquake and tsunami」の詳細全文を読む スポンサード リンク
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