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On Sunday Sept. 8th, my father and I had to make a trip to Northeast Iowa to pick up a cupboard. Since we were in the area, naturally we thought we should go fossil collecting as well. After doing a lot of research last week, we decided to do some scouting and see if we could find any new productive sites. The first site we stopped at for only a few minutes. All we were finding were stromatolites and the occasional Favosites coral. Later in the day we realized that the site was not in the Ordovician but in the Silurian. I may have to go back to collect some stromatolites to cut and see how well they polish, they were extremely abundant. We continued on and looked at our notes and topo maps(on paper even) to locate likely sites in the Maquoketa Formation. We found one site that showed the contact between the Clermont and Ft. Atkinson members of the Maquoketa and searched for a while. It seemed pretty void of trilobite material, but I did find a beat up cephalon of a Bumastoides beckeri that I didn't collect. I was surprised to find a small crinoid and despite my father's heckling I collected a section of worm tube/burrow free of matrix. Our next location turned this fun scouting trip into a fantastic outing. After spending some time looking at the shale my father shouted "We're going to be here a while!" I asked why and he told me to come and see. I walked over and he showed me a rock and I immediately recognized what it was, though I have never seen one it person. It was a cephalon of an Ectenaspis beckeri, one of the strangest looking trilobites in the Maquoketa Formation. Shortly after that I picked up another cephalon in similar condition. After 2 more hours of battling brush, grass and the occasional snake we left with 4 cephalons and a pygidium. I also picked up a sponge and an unusual curved cephalopod, but that was quickly overshadowed by the trilobite parts. After decades of collecting the Ordovician of the Upper Mississippi River Valley it's very unusual to be able to add a species to our collection that we haven't collected before. The final stop of the day was an oldie but goodie. I didn't really have high hopes of finding a complete trilobite and was primarily looking for Ceraurus parts for study. After a while crawling around, my father yet again shouted out. He found a nice laid out Calyptaulax sp.; the cephalon is slightly covered so I can't properly ID it yet. And just like the Ectenaspis cephalons, I quickly repeted that I had just found a Calyptaulax, though his was much much nicer. Mine was a little disarticulated, the head was broken in half, it was rolled and smashed flat. Kind of a sad excuse for a bug, but it was a Calyptaulax! I continued my crawl and after collecting a few more trilobite parts I noticed a laid out Cybeloides iowensis! It was broken in a few spots, but I believe I have all of the rocks so it can be glued together. It looks like it should turn out quite nice. So the day started out as a scouting mission and ended up being one of the best collecting days of the season! Maquoketa first stop finds: Brachiopod And an out of focus crinoid calyx. I'll try to get a better photo tonight Maquoketa second stop Ectenaspis berckeri cephalons and pygidium: Sponge Curved cephalopod Final site photos on next post...

Preliminary work...(fossil report to follow if you want to skip this) About a month ago, my father and I found a site we had never been to. We discovered that Ectenaspis beckeri parts were in a specific zone at this site and decided to come back on Oct. 6th to find some more for our study collection. We also wanted to do a little mapping to figure out exactly where we were in the formation. There are two cuts about a quarter mile apart, one at the bottom(cut A) and one towards the top of the hill(cut B ). Through much research, we found out that cut B exposed the contact between the Clermont and Ft. Atkinson members of the Maquoketa formation. We also found out that when cut B was made the contact between the Elgin and Clermont members was exposed in the ditch. This gave us a baseline to figure out where in the section we were. There is a small bridge at the bottom of the hill near cut A so we contacted the Iowa Geological Survey and got the exact elevation of the bridge. We also got the elevation of the top of the Galena formation from the IGS at various points in the area recorded from core samples. The Elgin member of the Maquoketa fm. lies directly on top of the Galena formation. Since my father works at and engineering firm, he had easy access to a theodolite and leveling rod. We started at the bridge(since we knew the elevation) and worked our way up the hill to cut B. We took a number of measurements and recorded the change in elevation between the bridge and the contact between the Elgin and Clermont members. We then shot from the bridge to the end of cut A and recorded that elevation change. We then measured the height of the cut and the thickness and elevation of the zone that was producing the E. beckeri parts. Why did we do all this? Well, this information will give us the exact thickness of the Elgin member(in this area), the elevation of the E. beckeri zone, the "slope" of the Maquoketa fm.(in this area), and the potential to be able to map other possible E. beckeri sites. It will also be useful when we eventually donate our collection to a University, the more info the better. Now that our preliminary work was done we could finally start collecting! Next post... A picture of my father surveying the hill. I was behind the camera/phone holding the leveling rod.

All I can say is that it's a sponge... I've looked through "Sponges of the Ordovician Maquoketa Formation in Minnesota and Iowa" Rigby and Bayer, 1971 and can't seem to find a match there. The Maquoketa is similar in age to some of the formations in the Cincinnati area if that helps at all. Sponge Maquoketa Formation, Elgin member Upper Ordovician, Richmondian Northeast Iowa Size: 2.1cm long 1.7cm wide across bottom.

The weather was too nice on Saturday, April 27th to stay inside and work on house projects so I took a day off and went collecting. I hit up 2 different sites in the Maquoketa formation of Southeast Minnesota in search of trilobites and maybe crinoids. Unfortunately I didn't find either. I saw a bunch of parts of trilobites, but nothing rare/nice enough to warrant joining my collection, mostly Isotelus and Flexicalymene parts. I ended up only bringing one rock home, which may be a new low record for me. However, that one rock is pretty cool. It's a small piece containing 8 Ischadites iowensis. I have only collected a small handful of these unusual things and this is the most I have ever seen on one rock. Before this the most I had seen grouped together were 3, so 8 was a very big surprise. Ischadites iowensis (Owen, 1852) Maquoketa Formation Upper Ordovician, Richmondian Southeast Minnesota

With an extremely long winter, the snow finally receded enough to get some collecting done. This is the latest start to collecting in my memory, so I was extremely anxious to get out on the rocks. I did make a quick half hour stop on my way down to the MAPS fossil show on the 4th, but I didn't count that as an official outing. My father and I decided to hit the Maquoketa Formation and the Galena Formations of Southeast Minnesota on April 7th. We also brought along a long time collecting friend who joined us at MAPS. We hit the road at about 7am, and got to a small MN town and had breakfast in preparation for the day ahead. We got done at around 9:00 and headed to the first stop. As we passed the bank, I noted the temperature at a balmy 30f(-1c for the rest of the world). Luckily the breaking of the rock kept us warm. We spent 2hrs breaking the amazingly resilient Maquoketa Fm. and found some interesting things. For some reason my eyes were tuned to sponges and there seemed to be a plethora of them. We picked up a couple of the best ones, but left many more. Another unique fossil found at this site is an undescribed Ectenaspis trilobite. We found many cephalons, pygidiums and hypostomes. They differ from the Isotelus iowensis and I. gigas in that the cephalons and pygidiums are much more triangular shaped and the hypostomes are longer and more slender than the two Isotelus. I did find one trilobite that I'm not sure what it is yet, I'm hoping it's a cheirurid of some type. My camera died so I didn't get a photo of everything, maybe tomorrow... Ectenaspis sp. hypostome Find why I picked this up... We left there at 11:00 and drove back into town to do some antiquing and say adios to our collecting friend and then made our way to our next stop, a Galena Fm site. As we passed by the same bank, the temperature had warmed up to 33f(0.5c). There we picked up a few gastropods and even managed to find a trilobite. A few trilobite parts, including an interesting pygidium were also collected but my camera is dead... Anataphrus boreaus, you can see the eye poking up a bit Our final site was another Maquoketa cut where again we broke out trilobite parts, sponges, and some interesting feeding traces(they look better in the shade). Feeding traces I'm quite pleased with this first trip out and am anxiously waiting for the next trip!