This is a little off-topic, but nonetheless, somewhere near a (former?) US Army base in Brazil, there's a 60 ton dragline crane which sank (along with the wooden floats) into a swamp within several hours. My father was a Captain in the US Army Corps of Engineers during WWII charged with building hangars and runways in Brazil. One of his stories was the one about the dragline sinking into the swamp they were dredging to prepare for site construction. When that happened, they decided there wasn't load-bearing soil within 60 feet of the surface, so they rearranged the site plan. To my knowledge, it's still there.
__________________
We have met the enemy and he is us . . . Walt Kelly