Fossil Hunting near Fort Collins, CO

[HynerpetonHunter]

Hi everyone, it’s been a while since I have posted on here. Next summer my family is moving to the Fort Collins area and I was wondering if there were any sites or natural areas to hunt/collect in. I read on fossilspot.com that the south shore of Horsetooth Reservoir (west of Fort Collins) contains Late Cretaceous Fox Hills formation containing “Inoceramus, Ostrea, etc.”. I have already planned to get down to Florissant Fossil Quarry (despite the extremely expensive one hour access fee). My mom has friends with ranches in the central part of the state that have extensive land with mountain ATV trails. I’m still working out the formations of the area, but hopefully they are vertebrate bearing. If they are and include dinosaurs or phorusrhacids, then I would be more comfortable to brave the Mountain Lions, Fire ants and rattlesnakes for them. Near my mom’s friend’s ranch is Monarch Mountain, which is built on Ordovician rocks full of fossils. It is unfortunate that there is not many vert sites in Colorado that you can collect at. However, I will take invertebrate sites too. Of invertebrates I want Baculites or Placenticeras. Any help appreciated. 

[Top Trilo]

Kremmling Colorado has Cretaceous ammonites on BLM land, its southwest of Fort Collins. 

 

Colorado is very strict on collecting so while there's lots of BLM land its mostly west and no vertebrate collecting on BLM land, also you can not collect anything from road cuts anywhere in the state, even pet wood and inverts. 

 

Colorado has fossils almost all over the state, the hard part is finding one legal and accessible, if you find a place that's both, start searching and chances are good you'll find something.

 

I've really wanted to hunt the Ordovician exposures in the south central part of the state, but haven't gotten out yet. Good luck and share your finds!

[JohnJ]

4 hours ago, HynerpetonHunter said:

My mom has friends with ranches in the central part of the state that have extensive land with mountain ATV trails. I’m still working out the formations of the area

 

These are your best potential sites.  If they are located on fossil bearing strata of any kind, it would be educational and possibly productive for you to spend time there.  Keep in mind that any site recommendations you find online will be subject to public traffic.  Your Mom's friend's properties may have very little fossil hunting traffic.  Who knows what you might find?   

[jpc]

Ft collins is not a bad place to be based in.  As others have mentioned, the hard part of vertebrate collecting is actually finding a private landowner who will let you collect.  And there is far more private land east of the mountains than out west where so much is BLM land.  For example…There is laramie (lance/hell creek equivalent) and white river fms in weld county.  I can point you to a rancher who indeed said no when i asked, but i shant waste our time.   As for baculites, there is tons of pierre shale along the front range.  Every time i fly into or out of denver i get a window seat snd dream of setting foot in all the gullies visible from up there.

 

Don’t expect too much from your mom’s friend’s land.  Minimal vert material in the mountains, but studying the state geology map is a great start. You ought to consider joining WIPS westernpaleo.org.

 

Good luck and please keep us posted.

[jdp]

Depends where you are. I've collected quite a bit of Carboniferous, Permian, Triassic, and Jurassic vertebrate material throughout the mountainous parts of the state. I can't tell you what you'll find but the Salida area includes a lot of Sangre de Cristo formation and there's good late Carboniferous localities there...think temnospondyls and early synapsids. There's also pockets of Chinle and Morrison throughout the mountainous parts of the state and that is always worth looking at. Obviously you need to sort out land access; BLM collecting is a no-go.

[HynerpetonHunter]

Thank you all! I’m going to look into geologic maps of the areas. All your help is much appreciated!