Transmute Rock to Mud

This spell turns natural rock of any sort into an equal volume of mud. 

The depth of the mud can never exceed one-half its length and/or breadth. 

If it is cast upon a rock, for example, the rock affected will collapse into mud. Creatures unable to levitate, fly, or otherwise free themselves from the mud will sink and suffocate, save for lightweight creatures which could normally pass across such ground. 

The mud will remain until a dispel magic spell or a reverse of this spell, mud to rock, restores its substance — but not necessarily its form. 

Evaporation will turn the mud to normal dirt, from 1 to 6 days per cubic 1" being required. The exact time depends on exposure to sun, wind and normal drainage.

Rate of sinking is 1-ft per segment, i.e. 1-ft per 6 seconds or 10-ft per minute (round). 

Brush thrown upon the surface will stop sinking of creatures able to climb atop it (use discretion as to the amount of brush and the weight of creatures). Ropes can be used to pull creatures out of the mire, assuming that sufficient power is available — 1 man/man, 10 men/horse (or vice versa).

The mud to rock reverse will harden normal mud into soft stone (sandstone or similar mineral) permanently unless magically changed.

Except as noted above, and that the material components for the spell are clay and water (or sand, lime and water for the reverse), this spell is the same as the fifth level druid spell, transmute rock to mud.