Atmospheric muon fluxes underwater as a tool to probe the small-x gluon distribution

We compute deep-sea energy spectra and zenith-angle distributions of the atmospheric muons, both conventional and prompt. The prompt muon contribution to the muon flux underwater is calculated taking into consideration predictions of recent charm production models in which probed is the small-x behavior of the gluon distribution inside of a nucleon. We argue for a possibility to discriminate the PQCD models of the charm production differing in the slope of the gluon distribution, in measurements with neutrino telescopes of the muon flux at energies 10-100 TeV.