Pressure in kg's from snowshoes I'm planning on making a hiking trip to a remote location. There will be approximately 1.5m of snow, so I'll be using snowshoes. However, the area that I'm supposed to climb used to be a battlefield. From an old colonel I learned that the area has been demined, but there still may be mines that were left behind. I also know exactly what type of mines may be there, and all of them activate upon applying a force of 5kg. 
So, my question now is, how do I calculate how much force will be transferred through the snow from the top to the bottom ground where the mines are? For an example, the snowshoes are 68.6 cm x 21.6 cm in size, my weight with all equipment would be 115kg, the density of the snow ranges between 200-300 kg/m^3, with a height of 1.5 m.
I've tried searching online, but physics is not my strong suit, so I thought I'd ask here for help.
 A: I don't think you can answer this - at least not reliably.  The snow will pack down under your snowshoes.  The mine trigger will not.  So as the snow packs down under your weight, your full weight could easily come down onto the mine trigger.  the thinner and fluffier the snow, the more likely this is.  If you've ever stepped on a broken or cut-off branch sticking up through the snow, you've experienced this.  
A: It'll be quite different based on the type of mine. Some are triggered by tiny pins, others by a few centimeters wide pressure plate. The pin designs have a small pin that protrudes just above the surface, that triggers the explosives when depressed. The pressure plate designs have a circular pressure plate held up by a spring that requires X amount of force/weight to depress, and can be buried under the soil.
68.6cm x 21.6 = 1481.76cm2
115kg / 1481.76cm2 = ~0.077kg/cm2
Given you figures, your shoes will be exerting a pressure of ~0.077 kg/cm2. Assuming you step on a mine with a pressure plate that has a 5cm radius, you'll be exerting
(3.14159  x  5cm  x  5cm) x ~0.077 kg/cm2 =
(~78.5cm2) x ~0.077kg/cm2 =
~6kg of weight down onto the mine. I hope it's a dud.
Snow compaction is very difficult to model, but as an anecdote I'll cite that my feet always seem to go straight down into the snow, and leave a hard packed footprint. On top of that, if it's light fluffy snow the particles aren't going to form strong lateral linkages, so again all the load is going to go straight down. You should expect pressure figures near the ones I listed.
Also, consider that over time the pressure-plate spring is going to weaken. Out of the factory they might have triggered at 5kg, but now they might only need 1 or 2.
