Primary waves, or P-waves, are the speediest of the three kinds of waves and therefore the first to arrive at a seismograph station after there has been an earthquake.They travel through the upper crust of Earth at speeds of 4 to 5 kilometers per second, but near the base of the crus...
Seismic waves-energy waves produced by earthquakes-permit scientists to determine the location, thickness, and properties of Earth’s internal zones. They are generated when rock masses are suddenly disturbed, such as when they break or rupture. Vibrations spread out in all directions from the sourc...
分享更多托福雅思资料 1 人赞同了该文章 Seismic Waves Seismic waves-energy waves produced by earthquakes-permit scientists to determine the location, thickness, and properties of Earth’s internal zones. They are generated when rock masses are suddenly disturbed, such as when they break or rupture. ...