MAGNITUDE 8'4, M 7'9, AND M6'2 EARTHQUAKES STRIKE INDONESIA

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MAGNITUDE 8.4, M 7.9, AND M6.2 EARTHQUAKES
STRIKE INDONESIA

• OCCURRED WITHIN 24 HOURS OF EACH OTHER
• ALL HAD SHALLOW HYPOCENTERS OF ABOUT 20 KM (12
  MILES)
• CASUALTIES WERE AMAZINGLY LOW
• SEPTEMBER 12-14, 2007

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MAP OF REGION
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GEOLOGIC SETTING OF INDONESIA
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GEOLOGIC SETTING OF INDONESIA

• Indonesia has 245 million people located in the
  Worlds largest archipelago on the Ring of Fire
  who are at risk from earthquakes, tsunamis,
  volcanoes, and landslides.
• Earthquakes, tsunamis, and volcanoes occur as a
  result of ongoing subduction of the
  Indo-Australian plate in the vicinity of
  Indonesia..

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INDONESIAN EARTHQUAKES

• The first two quakes of magnitude 8.4 and 7.9
  struck in Western Indonesia.
• The second quake caused more damage than the
  first.
• The third earthquake, M6.2, occurred on Sulawasi
  Island on a different fault system.

• The M8.4 quake on Wednesday triggered a 3 m (10
  foot) tsunami wave run up.
• Surprisingly and fortunately, most of the
  tsunamis wave energy was directed away from
  Sumatra Island
• Even so, hundreds of houses along the coast were
  damaged.

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INDONESIAN EARTHQUAKES

• Ground shaking from the M8.4 earthquake damaged
  buildings along Sumatras coast and in Padang.
• The quake was felt strongly in neighboring
  Singapore, Thailand, and Malaysia.

• Buildings in Padang, capital of West Sumatra,
  collapsed and some caught fire.
• Mosques, houses, and a school collapsed.

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TEMPORARY MOSQUE LAIS, BENGKULU
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DAMAGE TO HOUSING LAIS, BENGKULU, SUMATRA ISLAND
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DAMAGE TO CATHOLIC SCHOOL
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DAMAGE TO BUILDINGS MUARA MARAS, BENGKULU
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GEMERGENCY MEDICAL BENGKULU, SUMATRA ISLAND
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GROUND FAILURE BENGKULU, SUMATRA ISLAND
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INDONESIANS EVACUATE TALL BUILDINGS JAKARTA
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MALAYSIANS EVACUATE TALL BUILDINGSKUALA LUMPUR
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TSUNAMI WARNINGS

• Local and regional tsunami warnings were issued
  immediately after the M8.4 and M7.9 events.

• Remembering the 26 December 2006 earthquake
  and tsunami, residents of Sumatra Island, Sri
  Lanka, and Thailand reacted quickly and
  effectively to the warnings.

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TSUNAMI DAMAGE SERANGAI, BENGKULU, SAMATRA
ISLAND
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TSUNAMI DAMAGE MUARA MARAS, BENGKULU
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TSUNAMI WARNING IMPLEMENTATION CHENNAI
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TSUNAMI WARNING SUBURB OF COLOMBO, SRI LANKA
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TSUNAMI WARNING EVACUATION SRI LANKA
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AFTERSHOCKS

• By Friday, September 14th, more than 40
  aftershocks of the M8.4 event had occurred.
• One was assigned M6.6, but it was not large
  enough to generate a tsunami.

• The aftershocks exacerbated existing damage and
  traumatized the already frightened residents on
  Indonesias Sumatra Island who huddled in tents
  and remained outside their damaged homes.

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RESIDENTS REMAIN OUTSIDE BECAUSE OF AFTERSHOCKS