This will be a smorgasbord post, including one drawing, splitting some gifted shale from abroad, and two prospected sites + finds. First up, my most recent use of the pencils: Next, a lot of Conausaga shale (Cambrian) from Georgia, USA gifted to me by my forum friend who came to visit. I took him to Arkona, but we didn't come away with much. I did only slightly better on a second visit when my friend Roger made his annual visit to Canada. But here is a few of the bigger chunks from the 5 gallon bucket: I made a first pass through these to break them down a bit further, leaving some other chunks outside in the bucket to collect rainwater. They split easier when water-logged. Preservation is a bit dodgy in this shale, but the trilobites are numerous, dominated by Aphelaspis brachyphasis. Here is a shot of an interesting deposition littered with a few trilobites: A collection of pieces with confirmed trilobites: Closeups of a few of the trilobites themselves: My first stop in prospecting for new Ordovician sites was in search of the Whitby Fm shales. Viable Ordovician spots are few and far between as access is restricted given that only one quarry in Ontario permits us biannual visits, development, private property, or provincially protected parks that forbid collecting. This means we are having to fall back on prospecting for new sites, many of which are quite small and require more work to reveal. The pocket I was working was so tiny that it was exhausted in half an hour. Here is some assemblages of Pseudogygites latimarginatus moults. Sadly, nothing complete, but complete ones are rare. I did take home this chunk for further splitting: Site number two involved the highly diverse and fossiliferous Verulam Fm. Outcrops of this formation only occur in some creeks, and in quarries. For us trilobite hunters, the Verulam and Bobcaygeon Fms have the most diversity of any formation in Ontario. For obvious reasons of not wanting to see the site plundered by over-collecting, I am not posting any location details -- not even pictures of the strata! We have to take extra care these days given the paucity of productive sites. Here is some typical litter: All layers were largely dominated by Isotelus gigas, with some examples of other trilobites in the mix. The Isotelus usually appear as fragments, some of which would have belonged to 30+cm individuals if complete. But I'll save the best (trilobites) for last. First up are some typical shell bed hash plates from the uppermost part of the layers. All of the layers contain gastropods, brachiopods, some crinoids, trilobites, and nautiloids. Bryozoans were noticeably absent from most layers. A weathered nautiloid displaying calcite-filled siphuncle: I tend to pocket the gastropod steinkerns, mostly of the Fusispira sp. Here is an assortment of steinkerns (gastropods and a few nautiloids near the bottom right) and three brachiopods (Rhynchotrema?). Let's get to some trilobites. Incomplete ventral examples of Ceraurus and a juvenile Isotelus sporting the long genal spines. Heads up. One fairly large Flexicalymene senaria cephalon (over an inch wide) buried in matrix, and a juvenile Isotelus gigas. On the left is a half complete Isotelus from the shell bed layer. Finding them even this intact within such a sifted, turbid zone is uncommon. On the right is the fine specimen Deb found with an exquisitely preserved left eye. The eyes are the most vulnerable area on these bugs, prone to easy breakage. I'll be able to prep this nicely, even if it is not fully complete. My trip-maker is this 3ish inch semi-enrolled Isotelus. Both eyes are missing, and some parts of the shell are missing, too. The prep is going to have to be delicate as cracks tend to run all through the fossil, and the skin -- although thick -- is very flaky. I spent about 4.5 hours at this site and only managed to examine about a quarter of it. This was not an all-out excavation visit, but an exploratory scouting mission to track the layers themselves to better guide future visits. For me this is very exciting as it is getting very hard to find viable locations in the Ordovician of Ontario. I hope to get back there again this summer. But it is back to the Devonian for me with two other potential sites to prospect next weekend.
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Kane Faucher
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February 2024
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