Backgammon according to the normal movement rules. The first player to bear off all fifteen of his/her own checkers wins the game. If the opponent has not yet borne off any checkers when the game ends, the winner scores a "gammon", which counts for double stakes. If the opponent has not yet borne off any checkers and has some on the bar or in the winner's home board, the winner scores a "backgammon", which counts for triple stakes. To speed up match play and to provide an added dimension for strategy, a doubling cube is usually used. The doubling cube is
Ridge push flat slab subduction, one of the few places in the world where this currently occurs. Ridge push Ridge push or sliding plate force is a proposed driving force for plate motion in plate tectonics that occurs at mid-ocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere below mid-ocean ridges. Although it is called ridge push, the term is somewhat misleading; it is actually a body force that acts throughout an ocean plate, not just at the ridge, as a result of gravitational pull. The name comes from earlier models of plate tectonics in which