Mechanism:
(1) The material is a thick, viscous, semi-liquid mixture of sand or mud with water.
(2) When a person steps on the area the pressure causes the material to liquefy and the person sinks in a little. If the person struggles then s/he will sink in a little further.
(3) The material encircles the leg in a thick, air-tight grip. Trying to remove the leg causes a suction which pulls the foot back down.
(4) Further movement creates a vicious cycle that can draw the person further in.
Drowning in quicksand or a mud trap can usually be avoided.
Risk factors for a serious problem:
(1) The person is all alone.
(2) The person panics and struggles uncontrollably.
(3) The person has a massive heart attack.
(4) The person is trapped and unable to avoid another hazard (rising flood waters, an animal, etc).
(5) The person becomes unconscious because of a head injury, massive bleeding or for some reason.
(6) The person becomes seriously dehydrated or suffered heat stroke before being able to get out.