|Speaker:||Hans Petter LANGTANGEN, Simula Research Laboratory, Lysaker, Norway|
|Place:||Room B101, Cybernetica Bldg, Akadeemia tee 21, Tallinn, Estonia|
|Time:||Monday, November 20, 2006, 16:00|
"Simulation of Tsunamis Generated by Earth-Asteroid Collisions"
Throughout its history of existence the Earth have been hit by asteroids and comets. Impacts from the largest objects may have causeddramatic environmental changes. For example, impacts are now commonlybelieved to explain sudden mass-extinction of species, with theChicxulub impact (65 Mya) and the extinction of the dinosaurs as theprimary example. Giant tsunamis may be generated from marineimpacts. These tsunamis may have disastrous regional and, possibly,even global effects. In this talk we look more closely at a specificmarine impact that took place 142 million years ago in the Barentssea. The impact occured in a depth of about 400 m and formed a craterwith a diameter of 40 km. The resulting waves are estimated to be100-200 m in height.
We outline how such a multi-disciplinary, multi-physics, andmulti-scale problem can be attacked, and what kind of mathematicalmodels and numerical methods we have applied for simulating thetsunami propagation. Comparison of such impact events withearthquake-generated tsunamis, like the one on Dec 26, 2004, will bemade. Finally, we discuss shortcomings of the models and suggestpossible improvements.