The Fossil record in Montana stretches all the way back to the Precambrian
Paleontology in Montana - Wikipedia
I agree that would have been a nice shout-out.
I’m fairly certain it is indeed (or at least, is meant to be) Montana.
Yes, Alan and Ellie’s dig site is in Snakewater, Montana.
“Hammond wants Alan Grant.”
“Grant? You’ll never get him out of Montana.”
“Why not?”
“Because Grant’s like me… He’s a digger.”