This is a surprisingly hard question to find the answer, because every google result seems to be for Styrofoam Halloween tombstones. And I suspect the answer is so obvious that cemetery and mortuary sites don’t think it is worth mentioning.
So - do tombstones get buried or anchored partially in the ground, or do they simply sit on top?
This should help somewhat; The tombstone itself is not typically set in the ground.
But obviously, not all tombstones are set on top of granite foundations as shown in the video. Those that aren’t must be set some distance into the earth, I’d guess at least a foot, or else they would fall over almost immediately.
And if anyone needs confirmation, google “old graveyard” and look at the images, e.g.
These old tilting gravestones would obviously have fallen over completely if the base was not buried a considerable distance into the ground.
This is the webpage for Show Low Cemetery in Show Low Arizona that details how headstones are to be installed.
I would guess that other cemeteries have similar requirements for memorial installations
Oh look, something I actually know something about.
There are a couple of different types of stones and how they are placed.
The older, flat ones, are usually buried in the ground. If you’ve ever actually seen one they can be a good 2-4 feet in the ground. I know I’ve helped move some that are a good 4-6 feet long. At least in my area, starting in the late 1800s they would sometimes provide a slotted base that the stone could be slid into. Some of those would be buried, while others will sit on top of the ground.
The ones like What_exit showed have a wider base that sits on the ground, and should have some sort of gravel base under it. The stone then sits on top of the base. There’s generally nothing holding the stone to the base except weight, there is a seal that goes around between the base and the stone, but that’s only to keep water out.
There was for a while the use of metal pins that held the stones to the base, but those tend to bread after awhile since the metal expands and contracts. When these are repaired they will either get rid of the pins or use some sort of plastic pins.
This is why one has to be careful around tombstones, they might be heavy, but they can be pushed over easily. And once the newer ones start to lean they should be leveled so they don’t fall over. The older ones that lean probably aren’t going to fall over, but could break.
Here’s a link to to the original tombstone of Canada’s unknown soldier. When his remains were repatriated to Canada, the tombstone came along and was installed in the Canadian War Museum.
There’s a clear weathering mark showing how much of it was buried below the surface.
https://www.warmuseum.ca/learn/tombstone-of-the-unknown-soldier/
Neat fact: the room where the tombstone is located in the Museum has a narrow skylight, positioned so that the sun will shine directly on the tombstone at 11 am, November 11.
Old-style tombstones should have a significant amount below ground to keep them from falling over. But I’ve seen a fair number of old cemeteries with stones fallen over, that clearly weren’t more than a couple of inches below ground.
In Mr Monk and the Genius, the killer tried to throw off Monk by swapping two headstone over graves, so the wrong body would be exhumed. Aside from how unlikely it is a guy built like David Strathairn could lift two 500 lb gravestone by himself on short notice without leaving any marks in the ground, if it were buried in the ground that would have been too much. You wouldn’t need Monk-level powers of observation to notice. I think from this thread that it could have been sitting on top of the ground. It had a wider base. So score 1/2 for the writers.