  Accretion onto compact objects in X-ray binaries [black hole, neutron star
(NS), white dwarf] is characterized by non-uniform flow density profiles. Such
an effect of heterogeneity in presence of gravitational forces and pressure
gradients exhibits Raylegh-Taylor gravity waves (RTGW). They should be seen as
quasioperiodic wave oscillations (QPO). In this paper I show that the main QPO
frequency, which is very close to the Keplerian frequency, is split into
separate frequencies (hybrid and low branch) under the influence of the
gravitational forces in the rotational frame of reference. The observed low and
high QPO frequencies are an intrinsic signature of the RTGW. I elaborate the
conditions for the density profile when the RTGW oscillations are stable. A
comparison of the inferred QPO frequencies with QPO observations is presented.
I find that hectohertz frequencies detected from NS binaries can be identified
as the RTGW low branch frequencies. I also predict that an observer can see the
double NS spin frequency during the NS long (super) burst events when the
pressure gradients and buoyant forces are suppressed. The Coriolis force is the
only force which acts in the rotational frame of reference and its presence
causes perfect coherent pulsations with a frequency twice of the NS spin.
