In the case of an earthquake having a 100-year average return time, there is about an 18 percent chance that such an earthquake will occur in the next 20 years and a 63 percent chance than it will occur in the next 100 years. On the other hand, there is a 14 percent chance that it will not occur in the next 200 years. Reverse Fault A rupture that results from vertical motion of two adjacent blocks caused by horizontal compression. Sometimes called a thrust fault. In a reverse fault, the upper of the two adjacent blocks moves relatively upward.
S waves oscillate the ground perpendicular to the direction of wave travel.
They travel about 1.7 times slower than P waves. Because liquids will not sustain shear stresses, S waves will not travel through liquids like water, molten rock, or the Earth's outer core. Seiche A standing wave in a closed body of water such as a lake or bay. It can be characterized as the sloshing of water in the enclosing basin. Seiches can be produced by seismic waves from earthquakes.