How do unexploded shells get found on the surface if they got buried when they fell?

after being fired from a canon they would bury themselves into the ground and make a crater

but if they didnt explode they would still be in the ground

how do they get to the surface to be found?

How do unexploded shells get found on the surface if they got buried when they fell?
Sometimes they don't get buried - the angle of their trajectory is shallow enough that they just bounce off the ground. Or maybe the soil or rock was hard enough that the shell (or bomb) just bounced off.
Reply:Well there are probably many ways, my knee jerk reaction is to say that it's most likely due to erosion.

However depending on the area an effect called "Frost Heaving" might be at work.

Anyone who's yard has ever "grown rocks" knows that this effect can move buried material to the surface.

Check the link for more info on Frost Heaving
Reply:Objects deposited in soil or some other ground matrix are subject to the prevalent geological tendency of that location. Some objects go deep by actually having material deposited and built up above them in sedimentary layers of one form or another. Imagine a shell landing in the forest and undisturbed for 40 years. 40 years of leaves piling on it and decomposing into peat. The object actually does not travel vertically but the surface level changes relative to it. Others are exposed through erosion of material from above them(wind, water, traffic erosion, human intervention). Still others are heaved upward by a consistent freezing and thawing of the ground material if that weather pattern is present. Most unexploded ordinance world wide is found most commonly by construction in the excavation stage, farming operations, livestock herding, or children playing, and regrettably not specifically in that order. Hope this helps.
Reply:possibly through shifts in the eath where they fell over time, as well as soil erosion. things tend to shift upwards after they have been burried.

wesley