What kind of dynamical phenomena appear after a homoclinic bifurcation of an area preserving diffeomorphism? First we will remind some known results (mostly by P.Duarte) on conservative Newhouse phenomena and properties of the standard map, and then explain how those results can be improved to get a better understanding of the conservative Newhouse phenomena. In particular, we will show that stochastic sea of the standard map has full Hausdorff dimension for sufficiently large topologically generic parameters (a well-known open conjecture claims that it has positive measure).