'First Motion'
Untitled Note
First Motion
Sunday, January 05, 2014
6:00 PM
first motion: on a seismogram, the direction of motion at the beginning of the arrival of a P wave. Conventionally, upward motion indicates a compression of the ground; downward motion, a dilatation.
Created with Microsoft OneNote 2016.
Created: 2014-01-05
Updated: 2014-01-05