Silver said:
Big Muddy rancher said:
Thanks for a great set of Pics Jody. We have some mounds similar to those out in the hills on the ranch. One explanation I have heard was a spring underneath. Might be the case.
Some mounds are formed by meteor strikes. Better get your metal detector out!
I'll go "off the wall" --how about diamonds?! Diamonds are brought to the surface with tremendous speed and force. Ejected material goes thousands of feet into the air. Typically collapse back on itself, forms a crater--called a 'craton'----north of yellowknife, deposits are often under lakes.
Deposits are commonly in a carrot shaped 'pipe'---two types of pipes, kimberlites and lamprolites. Lamprolites usually have no diamonds. Some places--like eastern montana--they form mounts. I'd call Tiegan Butte---on hi way 200, about where fergus county meets petroleum county--a kimberlite.
When material--including a lot of 'mud'--starts tumbling back to earth, sometimes 'mud balls' are formed. Maybe kinda a lime green, ---cut into one with a rock saw, and if you hit center you'll find kinda an 'acorn' of kimberlite---and can see how it was built up, kinda like a muddy snowball and in a swirly pattern. You'll see them lying all over, around some 'mounds' several miles n of 200 in above area.
Typically, you'll find pyrite, mica, graphite, garnets, etc and even see them on surface of mud ball. These are called 'indicator minerals' fyi.
The ones n of yellowknife---evidently semi tropical or at least pretty warm when they were formed---I've got wood that came from there, grain similiar to redwood---several million yrs old---some petrified, some you could carve or burn---
If you like gawkng out the window and wonderin 'what the hell caused this?!" when you're road trippin, there's books available for every state
"Roadside geology of......." Last one i bought was for utah--utah's got lotsa interesting stuff---think i got it at blm in denver, but they're around, rock shops, etc.
