My OperaBiggest subduction zone earthquakes
Monday, January 30, 2006 7:54:34 PM
The most powerful earthquakes occur in subduction zones, areas of the sea floor just offshore where two tectonic plates meet and one dives beneath the other. But not all subduction zones create equal powerful earthquakes, and the question is, WHY?
As the subducting plate slides beneath the upper plate, stress begins to build where the plates meet and the upper plate can deform to create a large structure called a forearc basin. With time this basin, a sort of a bowl-shaped depression, fills with sediment. It appears that the most severe subduction zone earthquakes occur in areas where such sediment-filled basins are found (like the earthquake that triggered the Boxing Day Tsunami in 2004). So the weight of this sediment may play a major role.
Hypotheses for why earthquakes associated with forearc basins can be so severe are treated in a paper published in the February edition of the journal Geology.
EurekaAlert at http://www.eurekalert.org/pub_releases/2006-01/uow-scb013006.php
Ole
As the subducting plate slides beneath the upper plate, stress begins to build where the plates meet and the upper plate can deform to create a large structure called a forearc basin. With time this basin, a sort of a bowl-shaped depression, fills with sediment. It appears that the most severe subduction zone earthquakes occur in areas where such sediment-filled basins are found (like the earthquake that triggered the Boxing Day Tsunami in 2004). So the weight of this sediment may play a major role.
Hypotheses for why earthquakes associated with forearc basins can be so severe are treated in a paper published in the February edition of the journal Geology.
EurekaAlert at http://www.eurekalert.org/pub_releases/2006-01/uow-scb013006.php
Ole
You must be 
Lagged2Death # Monday, January 30, 2006 9:53:23 PM
Ole Nielsennielsol # Tuesday, January 31, 2006 8:53:56 AM
- of the mayonnaise I mean.
Ole