This past year has been precedent-setting for fossil collecting as it has also meant a staggering number of new and fascinating specimens added to a collection that seems to have colonized a lot of space in the house. No fewer than 8 trips to Hungry Hollow, countless trips to my nearby “honey hole,” some visits to the Ottawa and Rideau rivers, and 2 fabulous multi-day adventures at Penn Dixie. Deb and I have found numerous trilobites, including several full prone Greenops widderensis, well over a hundred Eldredgeops rana rollers and prone specimens (this in itself a major change from a few years back when I hadn’t bagged even one full specimen), and some fairly large and nearly complete Pseudogygites latimarginatus. And that’s just the trilobites. Several new types of corals, gastropods, brachiopods, crinoids, and cephalopods were also added - and even a fish plate. So many were gathered, in fact, that I was glad to be able to sell off some excess in support of the United Way campaign at work. The above trilobite, Flexicalymene ouzregui, was my first fossil purchase, a gift to Deb for all her great work and finds this past year. It is Ordovician in age and from the Atlas Mountains in Morocco. Coral of the Year prize is tied with this specimen and one acquired from a trail. Both are Devonian A lot of contenders for Assemblage of the Year, but the usual stuff from Arkona can take a backseat this time. It is a tie between this gravestone-sized block of black shale from Ottawa with plenty of Pseudogygites latimarginatus trilobites (and nautiloids), and an assemblage of Eldredgeops rana from Penn Dixie Among a lot of brassy-coloured Goniatites and sundry other Devonian goodies, this slightly pyritized nautiloid from the Widder shale weathered out whole and not in its usual crushed state in the shale, earning it Cephalopod of the Year. It was a bit of a challenge to settle on Gastropod of the Year, what with some neat high-spired specimens, but let's give the honour to my specimen Naticonema lineata from the encrinal layer of the Arkona Fm. Although I did find a crinoid "bulb," I'm giving this pyritized beauty from the Arkona mud-shale Crinoid of the Year even if it is just a stem. Amidst hundreds upon hundreds of brachiopods collected this year, including giant spirifers and the like, I could have copped out and said all of them are deserving of the honour of Gastropod of the Year, but let's opt for this specimen that preserved the umbilicus. And the only fish fossil contender of the year, a confirmed fish plate from the Widder Fm Contenders for Trilobite of the Year are legion. Instead of simply picking the biggest or most "perfect" specimen, this year is a tie between a Greenops widderensis that Deb found in the brittle Widder shale of Arkona, and an Eldredgeops rana that had been twisted and wrenched into an odd configuration, found at the Hungry Hollow Mbr of the Widder.
What follows are some odds and sods I hadn't got around to posting. Until the 2017 collecting season! Keeping closer to home, I've managed to pull some interesting if not typical specimens from the Dundee Formation along the Thames River. I even found a pitifully small trilobite pygidium (really not worth showing). The more visually interesting specimens happen to be coral, a few brachiopods, and bivalves. Unless otherwise indicated, these are all from the Dundee Formation, of the Devonian age, Eifelian stage. Not shown in these images were the plentiful and more robustly ribbed Brevispirifer lucasensis. So, let's show rather than tell: A fairly well-preserved chunk of colonial coral (?Favosites sp.). I don't usually go in for coral, but this one was a must-have. Another busy hash-plate containing some rugose corals (?Zaphrentis sp.), a brachiopod (Rhipodomella sp.) and a bryozoan (Fenestella sp.). Now that I'm back on campus teaching again, I took a few more pictures of the fossils in the wall of the Visual Arts Centre. The picture above already appears in my pre-blog entry, and I had misidentified it as a coral rather than a sponge (although it is nicknamed a "sunflower coral" due to its resemblance to a sunflower). It is a Fisherites ?occidentalis (formerly Receptaculites occidentalis, Blainville 1830, genus changed in 1979, Finney & Nitecki). The building's composition is Tyndall Stone (trademark of Gillis Quarries), Ordovician in age (Maysvillian stage), in the Selkirk Member of the Red River Formation quarried in Manitoba - incidentally the same material used in the Parliament Building. It is a dolomitic limestone mottled by many corals and thalassinoides. Another image of the same limestone sporting two fairly large nautiloids side by side, siphuncle showing in the specimen on the right. There are also several large gastropods if you take the time to scan the exterior of the building. And here is one such gastropod, Hormotoma sp.
The mottling of this limestone was a bit of a puzzle for some while. The mottling is something of enormous interest for the ichnologist (study of fossil burrows and traces). Here are some helpful papers on the subject: Kendall, A.C., 1977. Origin of dolomite mottling in Ordovician limestones from Saskatchewan and Manitoba. Bulletin of Canadian Petroleum Geology, v. 25, p. 480-504. Myrow, P.M., 1995. Thalassinoides and the enigma of early Paleozoic open-framework burrow systems. Palaios, v. 10, p. 58-74. (PDF) Sheehan, P.M. and Schiefelbein, D.R.J., 1984. The trace fossil Thalassinoides from the Upper Ordovician of the eastern Great Basin: deep burrowing in the early Paleozoic. Journal of Paleontology, v. 58, p. 440-447. -- And that is all from me for now. I'll be heading back to the Penn Dixie site in early October, now as a new and proud member of the Hamburg Natural History Society, for a two day dig. |
Kane Faucher
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