Ok, the Great Valley is believed by some to be Ashely Valley. I was thinking, the Grand Canyon would almost match the description of the Great Divide, is between Utah and Arizona, and Ashely Valley is in Utah and so might be not too too far from the Grand Canyon.
I know this is all speculation,but do you think it's possible?
(I know, Sharptooth must be really buffed if he can fall into the Grand Canyon (and not get stuck either

) and live, well, at least live through that. Maybe though, he fell into a less deep part of it.
Anyway, LBT Sharpteeth have super powers that enable them to fall down big cliffs (films 1 and 6, and, considering those two, we can't even be sure the guy from film 8 is really dead!) and also get stepped on by a full grown longneck (film 10), oh and live, that's important! (Anyone can have those things happen to them and die!

)