  Potential energy surfaces of even-even superheavy nuclei are evaluated within
the macroscopic-microscopic approximation. A very rapidly converging analytical
Fourier-type shape parametrization is used to describe nuclear shapes
throughout the periodic table, including those of fissioning nuclei. The Lublin
Strasbourg Drop and another effective liquid-drop type mass formula are used to
determine the macroscopic part of nuclear energy. The Yukawa-folded
single-particle potential, the Strutinsky shell-correction method, and the BCS
approximation for including pairing correlations are used to obtain microscopic
energy corrections. The evaluated nuclear binding energies, fission-barrier
heights, and Q-alpha energies show a relatively good agreement with the
experimental data. A simple one-dimensional WKB model a la Swiatecki is used to
estimate spontaneous fission lifetimes, while alpha-decay probabilities are
obtained within a Gamow-type model.
