Insights into the Indian Ocean Tsunami from GPS, Altimeters and Tide Gauges

  • Date: 04/27/2007

Julie Pietrzak (Technische Universiteit Delft)


Calgary Place Tower (Shell)


The Sumatra-Andaman Earthquake and the subsequent Indian Ocean Tsunami caused colossal devastation. Understanding the distribution and timing of slip in such massive earthquakes and their potential to generate tsunamis is invaluable to the safety of coastal inhabitants. In this talk, a unique analysis of data collected from ~60 Global Positioning System (GPS) sites is presented. These data are used in combination with different rupture plane geometries to model the slip along the fault interface during the Sumatra-Andaman Earthquake. From this analysis, vertical displacements of the Indian Ocean floor are derived and used to drive tsunami simulations using two recently developed unstructured mesh ocean models. The predicted tsunami is tested against independent satellite and coastal tide gauge data. Our results suggest rapid slip along the fault of order 20m in the South and 10m in the North. Furthermore our results suggest that the 9 minute propagation time of the rupture, through constructive interference of tsunami waves, strengthened the devastating tsunami in Southern India, Sri-Lanka and Thailand. Here we show that the GPS system in place at the time of the Sumatra-Andaman Earthquake could have been used to provide a reliable forecast of the Indian Ocean Tsunami within about 30 minutes of the earthquake. We conclude that GPS data should be included as an important component of future tsunami warning systems.

Other Information: 

PIMS is presenting a series of lectures at the Calgary Place Tower 1 in downtown Calgary. These lectures, given by experts from the PIMS Universities, will focus on mathematical techniques and applications relevant to the oil and gas industry and will demonstrate the utility and beauty of applied mathematics. The talks are aimed at a general audience. Attendance may qualify for APEGGA Professional Development Hours.