  The problem of internal gravity waves generation by a point source moving in
a stratified medium varying with respect to all spatial variables and time is
considered. The fact that the characteristic horizontal scales of density
variation may be large as compared with lengths of internal gravity waves makes
it possible to solve this problem by means of an approximate method analogous
to the WKB method. Therefore, in investigating the problem of internal gravity
waves generation by a point source moving in a stratified horizontally
inhomogeneous unsteady medium solution for individual mode must be sougth in
the form of waves of a special type - Airy and Fresnel waves, where special
functions allow to describe internal gravity waves field structure both near
and far from individual mode wave front. Then the problem is reduced to the
solution of the eikonal equation with some conservation laws perfomed at its
characteristics.
