The area that could be protected was a cube whose sides were no bigger than the caster's level times 10 ft (3 m). Once protected, the effects of natural disasters could not breach the barrier set up by land of stability. Water from floods, winds and objects carried by windstorms, debris and snow from avalanche, and even lava and ash from a volcano were diverted around the protected area. Earth movement, vibrations, and fissures from earthquakes were also prevented from disturbing the protected area. Protection lasted for one day per level of the aster. Land of stability did not prevent damage from calamities already in progress, nor did it prevent magically generated or simulated disastrous events.