  This paper addresses long waves on the water surface. It is assumed that
initially the water surface has not yet been displaced from its mean level, but
the velocity field has already become different from zero. This means that the
motion of a body of water is triggered by a sudden change in the velocity
field.
  The long wave is modeled mathematically as a specific wave packet. The model
is used to estimate duration of the wave origin formation, size of the origin,
water elevation in the origin, energy supplied to the water by the quake,
distribution of wave heights in the wave packet. Relationship between group
velocity of the packet and phase velocity of the packet's wave of maximum
height is revealed. These results are applied to Kuril tsunamis of November
2006 and January 2007.

Atmospheric and Oceanic Physics