Tuesday, March 22, 2011
Supershear Strike-Slip Earthquake
So, this is why it is a supershear. The rupture velocities at the bottom go up to 6 km/s, which is the P-wave velocity. For 'normal' earthquakes, the rupture velocity should not exceed 3 km/s
And this is what it does. It produces firm-ground PGV's at over 1 m/s. When I'm pretty sure the glass-reactors were knocked out at 0.1 m/s, and Chile's cheap condos were knocked out at 0.7 m/s, you can imagine what 1.2 m/s can do! Multiply that by 10 for soft soil basins, and the dirt flies in the air!
Please note that these people were also intelligent enough to just consider PGV for engineering purposes. :)