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What layer are the ammonites in, the yellow stuff? And in that Km? I went once and covered roughly the parts marked on your map here in red. I found a lot of the gastropod stuff but not the ammonites.

Instead of dealing with the Friday southbound traffic I decided to set a 5 AM alarm and hit the road early. The drive is about 105 mile/168km with light traffic and I arrived at dawn. With a somewhat decent bearing and familiarity of Mounds Reef, I decided to go off the map and fossil charts I had put together from my research. An additional 25 miles south lead me to Mt Elliott and a right turn onto BLM land. Mt. Elliott is the highest peak of the Book Cliff range @ 7142 feet/2177m with a 2200 foot prominence. Maybe one day I'll go up it. But not today...today is fossil finding and enjoying the desert beauty. Mt. Elliott before the sun has crested its peak. A good profile view of a cuesta - the slope with a long back and short face. The fossil concretions weather out of the face and roll down below waiting their turn for a hammer splitting migraine...ha ha! I grabbed a bucket and hammer and hiked a couple hundred yards to the cuesta face. I was still in the shade since the sun was still climbing. Hmmm...where are the concretions? Lots of shale chips everywhere, some limestone slabs and a few boulders -too big to crack open. I kept walking around and soon realized there were no concretions in this area. Grrrrr....! I did find a few small sections of the right material and found bivalves galore, including one I have yet to find. I kept 2 specimens and headed back to the car in the center of the pic. Downhill hike - easy peasey! And then back onto the highway and north 25 miles back to the productive sites I'd previously visited. Mt. Elliott with the sun right above its peak. There had been some rain recently and I didn't account for washes or creeks being wet or muddy or both. Oh well... whaddya do with a low clearance front wheel drive street vehicle to cross a wet, muddy creek with a nice drop going in and out. YOU SPEED UP! Actually, I got out, checked it, picked a line to follow, got back in and went for it. No hesitating, no stopping. Just GO! No prob! I think my Chevy may have collected a fossil...some ancient mud and rocks for sure. No damage, no worries, Let's go, Steve-O! Almost there! These 5 spots were the main destination for the day. My last trip here was a great success so I'm hoping for a repeat. First one on the left = Nada! Nothing! I looked all along the base and there was very little going on. So...I made the most of it anyway and hiked up it. Some cool desert flora along the way. The cactus is Opuntia polyacantha. A prickly pear with many thorns. Not your friend while hiking and not paying attention. I've had those 3 inch spines pierce my boots at night while doing astrophotography. YEOW! Okay enough flora...let's get to some concretions! Oh! here's a nice one. Darn! I forgot the dynamite. This one is over a ton and embedded into the hill. How big is it? Doing my best Sisyphus impression. Nice view from the top. At the bottom, a concretion inside a concretion. No, I did not break it open. But the closeup shows where some enthusiastic fossil hunters hit it a few times. On to the next formation. See any concretions? Me neither...that's because they're on the back side. Don't ask me why. I can only say I found more on the East side than the West. Now we're cooking! Escargot - slightly overdone. One of the largest, nicest gastropods I've seen. ...and the spoils of the day. I failed to take many pics while excavating as it got dirt on my phone, in the case and gloves had to come off every pic. So these are from in the garage just now. I wet the Ammo to display better. Hoping it preps out...this looks like the crumbly kind. It was huge...but only a partial when I found it. You can see the keel at the top. Another could have been... How it looked when I cracked it open . No other parts. A bivalve. And the last one I opened before leaving. Made the day. A double! And the best of the day! As cracked open. I took a late lunch break at 2 PM and realized I was beat. My feet and hands were sore and my back hurt from bending over all morning. But it was a good hurt. I'm looking forward to prepping this one. This is probably the last trip to this location this year. I've covered quite a bit of the real estate where the concretions are found near the gravel roads and there are dozens of square miles of concretion locations not accessible by vehicle. Only on foot. Bushwhacking trails with off road vehicles, dirt bikes, jeeps, etc...das ist verboten. Just down the road and west of this location is an area with Palm trees and Sequoias to be found. Til the next adventure. Steve

Hey there, got a pickle for y’all. This one was given to me and it was said it was from Dakota sandstone in central Utah. Not sure if this means the Naturita Formation, very low Mancos Shale, or very high part of the Morrison formation. I was thinking it was a vertebra but with how deep the curve is I am wondering if it is a toe or extremity bone or some sort? added some closeups of it under a microscope, varied from 600x to 2000x magnification

I took a geology excursion a couple of weeks ago, and had the chance to explore the I-40 road cut through the Gallup Hogback east of Gallup, New Mexico. Rather to my surprise, I came across a nice oyster horizon within the Mancos Shale. I realize the preservation is sketchy enough to make precise identification difficult. I'm wondering if these might be "baby" Inoceramus. I'll try to post some better pictures of samples I brought home later. And, since I consider myself lucky if I even get the right phylum -- I suppose another possibility is ostracods.

I found this tooth several years ago while searching micro matrix from Colorado, which I am now certain is Mancos Shale. Never mind. Mystery solved. Lesson learned=I need to wear my glasses when trying to ID teeth from pictures lol It’s a Catshark or something similar.

Friday was a second trip out the the Windmill sites with a quad and a geologic map overlay. I scouted out a site further north that was across the arroyo. I am a geologist by training but not so much about fossils or minerals, mostly tracking layers and mapping.

Some of you may have seen my ammonite donation. If not and you are curious it is linked here: It is an important player in this trip. Anyway I thought I might describe my first trip to this locality and why you might realize it is a little more rare than the normal finds there. Some of this is part of a poster for the now cancelled Rocky Mountain Section of the Geological Society of America so if I ever do get to put my poster online I will post a link here so you guys can look at it too. For now here is a trip report.

Hello all, I thought this would be a fairly easy identification, given the distinct deep indentations in the ridge of this ammonite fragment. I looked in Fossil Index of NA, Invertebrate Fossils by Moore et al, a Collignoniceras survey and the Atlas of Cretaceous Life, online. This fragment comes from Mancos Shale near Moab, Utah. Help appreciated. And if you can suggest sources for this era and region I’d appreciate it. Thanks. Tom

Hello all I wonder if anyone can help me with this invert. It is from the area between Moab and I-70, in a formation identified as Mancos Shale by a former BLM paleontologist. Roadside Geology of Utah places this area as Cretaceous. The shell is 3cm long and and about 2.75cm side. The distinguishing feature is a grove running down the center on the longer dimension. There is sign of horizontal banding. I have looked in the Atlas of Cretaceous Life online, Index Fossils of No. Amer., Invertebrate Fossils by Moore et al and “Mid-Cretaceous molliscan record from west-central New Mexico. The closest pictures I find are in Invert Fossils, p 252, figure 6-34 as suborder Productacea juresania, but this item is Pennsylvanian-Permian. There are several other earlier brachiopods that look similar, but nothing cretaceous with this indent down the middle. The indent does not look like damage, but actually structural. I think, for some reason this is a mollusk, but may be wrong. I don’t know to what extent the surface of the shell was damaged in removing the overlayer. I will post another picture. Thanks for your help. Tom

Hello all, Before I post a ‘what is this’ query I’d like to see if I can ID seversl fimds on my own. I have a number of shells from the Mancos Shale near Moab. In terms of references I have Index Fossils of North America, and Invertebrate Fossils by Moore et al. The Index Fossils might have gotten me close but still, no cigar. Other sources I have are particular to ammonites. Can any of you suggest references I might find online that cover non-ammonite Mancos Shale fossils? Thanks, Tom

My girlfriend, Valerie and I planned a two week trip to New Mexico and Colorado to visit friends, see scenery, and attend the Peach Festival in Palisades. Of course fossil collecting would be a part of it. I spent a full day with PFOOLEY outside Albuquerque in the Puerco Valley hunting ammonites in the Carlile Member of the Upper Cretaceous Mancos Shale.

Hello all. Time for me to go to school again, and ask for help identifying this fragment of what I take to be an ammonite. I found it in Mancos Shale outside of Moab. This segment is about 10cm long and about 4.5cm wide. It is in a thin slab with no sign of the shell continuing on the underside of this piece of stone. The two photos show all that can be seen and the third gives a sense of the thickness of the rock. I was unsure of what this was until PFOOLEY called my attention to Kennedy et al. A Revision of the Turonian Members of the Ammonite subfamily Collignonceratinae. This helped me see I was looking at an ammonite. In fact, this looks to me fairly close to Kennedy’s fig 32 on page 39, for anyone who has this source. The spine has distinct bumps at the shell ridges and the ridges themselves are sharp and more widely spread. In his terms, I’d guess this is a robust rather than gracile structure. I do not think it is Prionocyclus since its spine, as pictured in Kennedy, seem to be smoother along the entire back. When I look on line at other families I see some went extinct earlier than the Cretaceous and some have clearly smoother shells. I don’t know the complete universe of ammonites that inhabited this area in the Cretaceous so don’t know who the other contenders might be. The two families I see are Collignoniceratidae and Prionocyclus. If I am close that it is in the Col. family, I don’t think it looks like c. jorgensen or c. praecox. It looks like c.woolari. After all this, my questions. Is this enough of a segment to make a reasonable identification? Is this Collignonceras? If not, what am I missing (seeing or not seeing)? As always, thanks for your help.

Hello all, I have what I believe to be a segment of an ammonite. I think this is in the Acanthoceratidae family. I can see the suture patterns very clearly. This piece is 15 mm long and was found in Mancos Shale near Moab. In ID-i got it I find the Cretaceous Atlas of Ancient Life particularly helpful. So first, am I on the correct track so far? If so, then I wonder how I can I go to the genus level of identification. I am looking at the robustness of the ridge pattern and see it is common with Acanthoceras, but there are other possibilities as well. Does an incomplete sample like this allow you to make a genus identification or not? Or is the best you can do make a probability statement, such as it is this or that? What specifically about this segment should I focus on to get to the next level and what source would you recommend for this type of identification? Is the key in the suture patterns? Thanks for your help. Tom

Hello all, here is another fossil for which I’d appreciate some ID help. It is about the size of a postage stamp. It looks to be a cross section of an animal. There were extensive ammonite shell fragments in the area and I wonder if this is a cross section of one? It was found in Mancos shale north of Moab, but before reaching I 70. I darkened the fossil so it was more visible. Don’t know that I like that effect. Thanks for your help.

This impression and partial exoskeleton is slightly larger than a postage stamp. It is from a Mancos shale deposit outside of Moab, between the city and Rt 70. I’m unsure of the words to use, but it looks like there was a central back carpace with a skirt around it. ID help much appreciated. Thank you.

I have seen this type of trace many times before...each time I wonder. Do you have any ideas? The knife is 3" in length...thank you for your thoughts.

I've been looking for an ID for this big boy. So far I've found this site (http://www.ammonoid.com/Prionocyclus.htm) but I'm not sure what I'm looking for to differentiate between them. Could anybody more knowledgeable help me out?

Hi Everyone, First Fossil ID post. This item was found in the Rio Puerco area around Cabezon Peak. Supposedly, this specific area is an outcrop of the upper Cretaceous, likely a transgressive sandstone deposit of the Mulatto Tongue of Mancos Shale. The specific location is termed Shark Tooth Ridge by many locals. I was initially told to be Bryozoan but have no further information. Any help with identification would be appreciated. There are two pieces that fit together as seen in pic Rio Puerco-0000. The main objects look to me (Extreme novice) like some bone or stem. The ribbing imprint seems come from the lower part what I see in Rio Puerco-0001 and Rio Puerco-0003. But the outside ribbed imprint on Rio Puerco-0004 was made by something not found. This was just laying clumped together on the surface of a ridge with washout flow. This is my first "potential" fossil find. I included a map for location purposes only. Thank you for any help coming my way. William