PAGER - M 5.9 - SAMOA ISLANDS REGION
Alert Version: 1Saturday, October 17th, 2009 at 10:45:27 UTCLocation: 16.3° S, 172° WDepth: 10kmEvent Id: US2009MWA5Created: 19 minutes, 43 seconds after earthquake.
Overall, the population in this region resides in structures that are vulnerable to earthquake shaking, though some resistant structures exist. On September 28, 2006 (UTC), a magnitude 6.9 earthquake 30 km South of this one struck Tonga, with estimated population exposures of 223,000 at intensity IV and 3,000 at intensity III, with no reported fatalities.
Overall, the population in this region resides in structures that are vulnerable to earthquake shaking, though some resistant structures exist. On September 28, 2006 (UTC), a magnitude 6.9 earthquake 30 km South of this one struck Tonga, with estimated population exposures of 223,000 at intensity IV and 3,000 at intensity III, with no reported fatalities.
Exposure Summary
Estimated Population Exposed to Earthquake Shaking
| Est. Modified Mercalli Intensity | Est. Population Exposure | Perceived Shaking | Potential Structure Damage | |
|---|---|---|---|---|
| Resistant | Vulnerable | |||
| X | 0 | Extreme | V. Heavy | V. Heavy |
| IX | 0 | Violent | Heavy | V. Heavy |
| VIII | 0 | Severe | Moderate/Heavy | Heavy |
| VII | 0 | Very Strong | Moderate | Moderate/Heavy |
| VI | 0 | Strong | Light | Moderate |
| V | 0 | Moderate | V. Light | Light |
| IV | 2k* | Light | none | none |
| II-III | --* | Weak | none | none |
| I | --* | Not Felt | none | none |
*Estimated exposure only includes population within calculated shake map area
| Population Exposure Population per ~1 sq. km. from LandScan  | Cities Exposed
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Shaking Intensity  | |||||||||||||||||||||||||||||||||||||
PAGER results are generally available on the Internet within 30 minutes of the earthquake’s occurrence. However, information on the extent of shaking will be uncertain in the minutes and hours following and earthquake and typically improves as additional sensor data and reported intensities are acquired and incorporated into models of the earthquake's source. Users of PAGER estimates should account for uncertainty and always seek the most current PAGER release for any earthquake.
