It would depend on the type of mine and how it activated (pressure or tripwire).
http://science.howstuffworks.com/landmine.htm
1- Blast - The most common type of mine, blast mines are buried no deeper than a few centimeters and are generally triggered by someone stepping on the pressure plate, applying about 11 to 35.3 pounds (5 to 16 kilograms) of pressure. These mines are designed to destroy an object in close proximity, such as a person's foot or leg. A blast mine is designed to break the targeted object into fragments, which can cause secondary damage, such as infection and amputation.
2- Bounding - Usually buried with only a small part of the igniter. When activated, the igniter sets off a propelling charge, lifting the mine about a meter into the air. The mine then ignites a main charge, causing injury to a person's head and chest. protruding from the ground, these mines are pressure or tripwire activated. You may also hear this type of mine referred to as a "Bouncing Betty."
3- Fragmentation - These mines release fragments in all directions, or can be arranged to send fragments in one direction (directional fragmentation mines). These mines can cause injury up to 200 meters away and kill at closer distances. The fragments used in the mines are either metal or glass. Fragmentation mines can be bounding or ground-based.
M14 Blast Mine:
Once it is armed, any pressure of at least 19.8 pounds (9 kg) can cause the mine to detonate. When the proper amount of pressure is applied it pushes down on the Belleville spring underneath the pressure plate. This spring pushes the firing pin down on to the detonator, which ignites the main charge of Tetryl explosive.
http://science.howstuffworks.com/landmine3.htm
Quoted from the website "How Stuff Works"
