Answer:
Tsunamis are most often caused by undersea earthquakes, which send tons of rock shooting upward with tremendous force. The energy of that force is transferred to the water. So, unlike normal waves that are caused by wind forces, the driving energy of a tsunami moves through the water, not on top of it. Therefore, as the tsunami travels through deep water -- at up to 500 or 600 miles per hour -- it's barely evident above water.
Explanation: