Very high energy neutrinos come from astrophysical sources and GZK interactions. Different neutrino sources produce different neutrino flavor ratios. In this thesis, we compare GRB neutrino flux with GZK neutrino flux in different energy ranges. The ratio between integrated neutrinos fluxes from these two sources are calculated as a function of chosen neutrino threshold energy. We propose a statistical method to reconstruct such a ratio from flavor measurements of neutrino telescopes.