The great Chilean Earthquake
- The 2010 Maule earthquake occurred off the coast of central-southern Chile on February 27.
- It had a moment magnitude of 8.8 and lasted approximately three minutes.
- It caused widespread devastation in the surrounding area.
Measuring Earthquakes
- Seismometers measure the energy released by earthquakes and provide estimates of an earthquake's magnitude and location.
- Satellite imaging can provide additional data.
Measuring City Locations
The Global Navigation Satellite Systems (GNSS) can measure Earth's surface to within millimeters:
- Scientists use two methods: differential and precise point positioning.
- For differential positioning, one stationary receiver is used to measure satellite signals. A moving receiver is compared with the stationary one.
- For precise point positioning, every GNSS receiver determines its precise location by comparing its measurements with a global network.
The New Research
- The team combined GNSS, seismometer, and satellite radar data to analyze the Maule earthquake.
- They found that strong shaking caused parts of the Earth's surface to be permanently displaced by several feet.
- Concepción and Talcahuano moved 2.57 meters (8.43 feet) to the west and 2.00 meters (6.56 feet) to the north.
The Effects
- The findings will help scientists understand the risks of future earthquakes in South America.
- They will also be used to update building codes and emergency response plans.
