Alluvial fan could be the answer. Alluvial fans are cone shaped deposits of sedimentary particles. The particles can be sand. silt, gravel or clay. These land-forms are formed at the mouth of canyons or in valleys where ephemeral streams can occasionally transport material to the mouth of the canyons. An ephemeral stream is one that is created after a shower of rain or other form of precipitation; they are not permanent streams. <span />
The answer is "5 minutes and 35 seconds".
Earthquakes create three kinds of seismic waves which are:P-waves that are primary waves, S-waves that are secondary wavesand surface waves,which land at seismic account stations in a steady progression.Both P and S waves enter the inside of the Earth while surface waves don't. Because of this, P and S waves are known as "body waves"
