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I lined up a couple more properties over the weekend so I made another trip out to exposures of the Cannonball Formation (Paleocene) and Fox Hills Formation (Upper Cretaceous). I only planned for two properties but the first was so large (an entire section with many outcrops) that I figured this was fine. It was a nice morning and much of the haze from the Canadian wildfires has subsided. Junipers often creeped over sandstone concretions on the cliffs. A slump exposure of Cannonball Formation viewed from the top of another exposure. The top of hills were often capped with hard sandstone. Loosely consolidated and worn sandstone in lower layers had abundant shell fragments but not much else. A couple more complete fragments might be identifiable. Distinctly bedded sandstone. A nice hike even if the fossils weren't good. Another hour long drive and I was at the Fox Hills site. Fossils were loaded here. Some free-weathered (these are compressed Protocardia subquadrata)... ...and lots in concretionary layers. There's quite a bit I brought back to prepare. Species I've noticed just in the outer concretion include indet. fish scales, Mactra warrenana, Piestochilus feldmani, Protocardia subquadrata, Pteria nebrascana, Pteria linguaeformis, Cucullaea shumardi, and Euspira sp., A split Hoploscaphites (~6 cm). I brought back the entire concretion intact. To the left are Mactra warrenana and below is wood. Some concretions were massive. This one was a little under a meter long. And unfortunately contained a worthy specimen. Unable to remove the whole concretion I removed the layers containing the ammonite by chisel. Annoyingly the ammonite went through both the outer concretion layers (already separated in part) and the inner layers so the layers will have to be reconnected during prep. It's about 8 cm long complete. The gem of the day is this ammonite which I originally thought was a Placenticeras. Despite the preservation it is an excellent find. It did require multiple repairs as I found it in multiple pieces. A puzzle and some glue later and I have this. It is difficult for me to imagine based on my experience but there are some reports of massive Sphenodiscus from the Fox Hills as well as Placenticeras being present although I haven't found any scholarly sources to back this up yet. Some sources claim they disappear before the Fox Hills. It seems I'll have to do some research when I get the time. Outer concretionary layer removed (other side is solid sandstone). Some "body" removed (outer shell adhering to other side). Removed body. Continuing up the hill there is another exposure, this time of the Timber Lake Member that represents brackish transition. Cattle trails were littered with Crassostrea subtrigonalis. No other species found.

Over the weekend I tried some new Fox Hills and Cannonball Formation sites as well as returning to a couple old ones. Most of the new Fox Hills site was covered in abundant Ophiomorpha, a decapodian trace fossil very typical for parts of the Fox Hills. Abundant free weathered pieces of the burrows. There was a rather large Crassostrea subtrigonalis oyster bed on the property. A common fossil in the upper Fox Hills but I don't often see them in the abundance of this site (fragments in the thousands). All white/sharp edges you see are oysters. The Prickly Pears are now fruiting here. I only grabbed a handful of the most attractive individuals. The black/grey sheen on some is very pretty. An Anomia micronema was attached to the matrix on one as a bonus.

The weather was nice so I decided to get out to a couple sites that were on my list. The first site is the site where a friendly pocket gopher throw up fossils at an otherwise barren spot. Only one pocket gopher mound had fossils. The nearby ones apparently never made it to the layer of Fox Hills strata, even the ones within a few feet of this one. An unassuming site. The fossiliferous pocket gopher mound. This time the conditions were fine for sieving so I proceeded to sieve this gopher's pile. Lots of shell fragments but also some more complete stuff. I rarely use my sieves in North Dakota because most sites don't have loose fossils like this. A little Pachymelania insculpta in the sieve. A bigger one. This poor guy was hiding out in the mound and got hit by accident as I was scooping soil. He seemed to recover. It didn't take long to sift the whole mound at which point I took the sorted fossils, labeled them, and moved onto a site I went to the last time I was in the area. I never finished surveying the rest of the property so I wanted to come back to make sure there wasn't anything more significant than last time. There was in fact. Large Mactra warrenana were common in the salt and pepper sandstone outcrop I discovered. These ones are about 3 cm across. The iron stained fossils stood out quite a bit. Lower in the horizon were more outcrops of that shale and claystone, becoming progressively darker towards the base. I only saw very small shell fragments in these.

I've collected another Fox Hills shark tooth and I wanted to see if anyone more familiar with Maestrichian shark species has any ideas on what it may be. Attached is a preliminary list of species present in the Fox Hills of North Dakota as reported from Hoganson in 1995. There have been additional species discovered since that are present in a recent publication but I don't currently have access to that paper. I do have experience with some of these from other Cretaceous deposits but I welcome input from anyone with ideas. Pictures of the specimen. It has been difficult to get clear pictures due to the size. The incomplete root also complicates things but it is rare enough to warrant a try at identification. The shape and direction of the blade, lack of cusps (it seems complete enough to make this determination) and general stoutness makes me think something along the lines of Paranomotodon but that's just a guess on current information. Labial surface Lingual surface

I had the opportunity to get out to my favorite area of the Fox Hills Formation last week right before the temp skyrocketed into the 100s. I returned to my favorite Timber Lake site as well as tried some new ones. The first site I tried on the way down was not an exposure of the Fox Hills at all but probably of the Cannonball Formation, at least in part. I didn't find anything at this site but it was pretty nonetheless. There's lots of exposed Fox Hills sandstone at my favorite Timber Lake site but the fossils are not as well preserved as those in the concretions. The concretions are often spectacular. This is from the site I describe as Timber Lake Exposure 1 in other threads. I did collect some small concretions pictured later. No large ones but there wasn't much erosion this year due to the dry weather and the lack of snow melt from the mild winter. This new site exposes more of the brackish portion of the Fox Hills Formation. There was tan and salt and pepper sandstone with sparse fossils throughout. The interesting thing was the white-gray claystones and shales exposed at the top of some hills. There were sparse fossils here as well that I took the time to collect just because it is unusual for the area. I haven't prepared anything from it yet. I think most, if not all, specimens were Protocardia subquadrata. I got around to preparing some of the stuff from the Timber Lake exposure. The ammonites in the overlying sandstone layers are typically "pancaked" flat. Typical concretionary material from the site with the abundant wood that is typical of the exposure. Typical immature Scaphitid ammonites. Just a portion of the body chamber. A rather large and robust Cylichna scitula. Aptychus. A swirly crystal Oligopytycha concinna. Ones missing the outer shell are common because of how the outer shell sticks to the concretion. Various other typical specimens are present in the concretions collected but I haven't had the time to prepare them yet. No larger ammonites are likely to be found as the concretions usually split along the plane of the largest ammonites but there may yet be some rarer small specimens present. This particular site has yielded crab fossils, a shark tooth, and many rare mollusc specimens. It's just a matter of finding time to continue preparing the concretions.

On the 1st I had the opportunity for another trip and made it out to Morton County. I was waiting until now to post the report because I wanted to finish preparing a crab to include in the report but I've been busy. I went to one Fox Hills Formation site but mostly I had sites lined up from the Paleocene Cannonball Formation and some Fort Union Group formations. Compared to Emmons County across the Missouri River there is less Fox Hills Formation and it is replaced mostly by the overlying Hell Creek Formation and Paleocene units. Some scenery showing outcrops of the Cannonball Formation at one of the sites. Outcrops are common but fossils in the formation are rather slim pickings. Small crab bearing concretions have been reported from the Cannonball Formation once in the past but the sites where they were collected and the species described has since been destroyed. A shame considering the overall rarity of crabs from the interior seaways and North Dakota overall. The concretions were instantly recognizable at this site but were sparsely fossiliferous. Because of that I was splitting most of the concretions in the field. Persistence did pay off and as I was about to give up I did come across a crab. Later I glued the concretion back together to prep it. After preparation. I was hoping for a more complete and well preserved crab (something like Washington crabs) but considering the rarity I really can't complain. This is Camerocarcinus arnesoni. A carpus underneath the carapace. I also found a manus in the concretion. An internal mold of Arctica ovata from a nearby site. Only one other Arctica was found. There is one more crab bearing concretion to prep but it appears to be much more partial. There's also some concretions I was unable to split in the field so I brought back to exert more muscle on them. Hopefully there will be more stuff.

Went to attempt some new sites in Emmons County North Dakota yesterday. It was a pretty intensive day (out for 12-13 hours) for only a little bit of fossils but I thought some people might like to see the usual trip report photos and fossils I did find. Extensive clayey shale exposures are always worth photographing. Some horses were curious what I was up to but eventually lost interest. I'm not 100% sure this is Fox Hills (the clayey shale exposures of the Trail City and Timber Lake members look a lot like Pierre Shale when not accompanied by sandstone) but it didn't produce so it doesn't matter. A worn roadcut exposure with various bits of Ophiomorpha sp. Part of the Timber Lake Member most likely. For those not familiar, these trace burrows are incredibly abundant in the Timber Lake Member in North Dakota and become scarce in the Iron Lightning Member (also called the Bullhead and Colgate). Here's some of the burrows in-situ at a different site. Sometimes they form complex connecting tunnels. Speaking of Ophiomorpha, an isolated butte in a crop field produced some of the most detailed specimens of them I've seen. I thought I was long done collecting Ophiomorpha specimens but in this case I made an exception. Pictures don't do the details justice. Petrified wood also occurred in the outcrop. Larger pieces are less common in the Fox Hills than the successive Hell Creek Formation and Paleocene formations. The small butte. To check other exposures on the property I had to traverse the fields. Other exposures of the Fox Hills Formation on the property were numerous but didn't produce anything but more Ophiomorpha (with lower quality than the butte). Bank swallow nests in the softer sandstone outcrops.

Despite the shortest and most mild winter I've experienced in North Dakota (getting out this early is rare) it still feels like it has been an eternity since I got out. Thankfully I finally got a hold of enough landowners to warrant a trip to the Fox Hills Formation and celebrate the spring weather. While most of the later sites I visited were a bust the first site of the morning was excellent and contained fauna not often found in the Fox Hills Formation in North Dakota. 3 new species for me in fact. This site represents a brackish transition area of the top of the Fox Hills Formation. A view from the collecting hills. Note the water bodies are still frozen. Some farmers were burning stubble in the distance. One of the more significant exposures. Compared to the other 2 outcrops on the hills this one was poorly fossiliferous. Anomia micronema and Crassostrea subtrigonalis (glabra) litter the surface of the worn outcrops. The bedrock was basically an oyster bed hash of graywacke sandstone. This oyster laden sandstone isn't unusual but you usually don't find the additional fauna (see below). In-situ Crassostrea in one of the unworn exposures. Some of the nicest specimens. Moving clockwise from upper right is Pachymelania wyomingensis, Pachymelania insculpta, Corbicula cytheriformis, Crassostrea subtrigonalis, and Anomia micronema. Pardon the bad picture and for our international friends the coin is about 1.9 cm. I took this picture for the landowner since he was interested and I included a scale he'd know. I was also too tired to retake it with my metric scales. I plan to take better ones later. Nice sculpture to the Anomia. Most were not so iron colored. There are some additional things in pieces of the sandstone I brought back. I have an idea what this is but want to prep it to see for sure. This is larger, about 5 cm across. On the way back to the main roads I found a farmer in the middle of nowhere with a sense of humor. I also collected a couple smaller concretions of the more typical ammonite Fox Hills concretions from another site. I'm not expecting much based on their size but if there is anything interesting post preparation I'll post those as well.

I've been posting Fox Hills Formation fossils from a recent trip but I feel that those are a poor representation of the often spectacular preservation and diversity of the Fox Hills Formation. Because of that I've decided to post some of my better Fox Hills specimens from North Dakota. We'll start with some lovely ammonites. Jeletzkytes nebrascensis is common throughout the Fox Hills Formation in the Timber Lake Member (perhaps a bit less so in North Dakota) and is a typical flagship species for the formation. This microconch from Emmons County is the largest complete J. nebrascensis I've collected. The slash mark is an unfortunate result of removing an ammonite from directly atop this one before I was aware of this one. I think it turned out well despite that.

A few weeks ago we had unseasonably warm weather and I decided to make a trip to central North Dakota and collect from some exposures of the Fox Hills Formation (Cretaceous). I've spent a lot of time in this formation but had some new areas I wanted to try. Views looking up and down on the main cut of a Timber Lake Member exposure. This was the most significant new exposure of the day. Most of the Fox Hills Formation in North Dakota is sandstone of various grain size. The characteristic concretions with fantastic preservation that occur in the type locality also occur in North Dakota, although the concretions at this site were not of that type. Some examples of the concretions of this particular exposure. Some Scaphitidae body chambers are present that were separated from the rest of the ammonite. Not exactly the quality I expect from the Fox Hills Formation.

Finally ... a short trek on the open prairie of Eastern Colorado and into a slice of the Cretaceous period. This was my first true jaunt since my move from the East coast and it was a welcome change to my normal routine. My journey really began several years ago when I purchased some shark teeth from a fossil forum member in Colorado. He regularly visits a site on private land in Eastern Colorado that contains (what we think) are exposures of the Fox Hills fm. , and are chock full of marine fossils from that time period. I contacted him several weeks after I arrived, desperate to get away from civilization, and honestly just looking for someone I can chat with about geeky fossil stuff. The rolling hills of harvested wheat and corn stretched as far as the eye could see.... The exposure with the most fossil concentrations sat in a rust colored band of loose sand/sandstone. The best pockets contained shells where the teeth and bone settled. I was there without most of my usual equipment. I wasn't sifting or digging for much more than an hour before we had to leave and came home with plenty of matrix and fossils to keep me busy for several weeks. Shrimp-like trace fossils. As well as Squatina sp. and Sand Tiger Shark, Carcharias sp. teeth .. as well as small fish teeth, small fish vertebra etc. can be found. Good thing he had some small screens or all of these wonderful finds would still be on the sandy slope. Average size for these shark teeth is about 10mm. Cheers, Brett PS. I'll wash the matrix and post any additional micro-fossils here.