  Using the molecular dynamics simulations we investigate properties of
velocity autocorrelation function of Lennard-Jones fluid at long and
intermediate time scales in wide ranges of temperature and density. We show
that the amplitudes of the leading and subleading VAF time asymptotes, $a_1$
and $a_2$, show essentially non monotonous temperature and density dependence.
There are two lines on temperature-density plain corresponding to maxima of
$a_1$ ($a_2$) along isochors and isotherms situated in the supercritical fluid
(hydrodynamic anomalies). These lines give insight into the stages of the fluid
evolution into gas.
