I've just returned from an almost week-long adventure to Manitoulin Island and surrounding areas. Three of us prospected numerous sites harvested from old literature, word of mouth, and satellite imagery, including a large number of road cuts, ditches, and piles. Most of our more productive and interesting finds came out of the Bobcaygeon Formation, north of Manitoulin, whereas many other sites were the wrong material, tapped out, overgrown, or far too weathered. In an effort to be circumspect about locations, no site pictures will be presented here -- only typical material and finds. I will cluster these slideshow style by site, with descriptive captions. Not all sites that we prospected will be presented here. Site #1 - Bobcaygeon FM upper intervalSite 1 was an upper interval of the Bobcaygeon Formation. Much of the Ordovician material around the Manitoulin area occurred in relatively near-shore environments (save for during Whitby/Collingwood time), and are all high energy. This means many of the specimens have been heavily disarticulated. Site #2 - bobcaygeon fm middle and upper intervalThis site contained the middle and upper portions of the Bobcaygeon exposures of the area, and was by far the most productive for trilobite diversity. SITE #3 gull river fm (?)This was a cut that has since weathered too much and become overgrown. Most of the horizons were blank. SITE #4 - ordovician - silurian boundaryOur search for eurypterids in the Ordovician-Silurian contact was not productive beyond finding numerous algal material. Site #5 - manitoulin fmThe dolostones of this formation contained nothing other than numerous corals and brachiopods. site #6 - Whitby/collingwoodLocating some Whitby shale, much of it was very dense and largely blank. No traces of trilobites were found. site #7This site was an aggregate of material from local roadcuts, with some variability of lithology. We were able to map it against a nearby road cut that was quite tall and had representation of every rock type we found in the pile. This was also the spot where the two trip-makers were found.
Overall, this was a long and exciting adventure with two incredible field comrades. There were certainly more misses than hits in our prospecting, but the occasional stellar finds made up for some of the frustration and disappointment. It was no less thrilling for me to find examples of ten new species for my Ontario collection: Gabriceraurus dentatus Bathyurus (Raymondites) sp. Eomonarachus intermedius Bumastoides milleri Physemataspis pernododusus Ectenaspis homalonitoides Ceraurinella trentonensis Sceptaspis lincolnensis Bufoceraurus bispinosus Dolichoharpes dentoni I'll tie up this blog post with two trilobites that were waiting for me on my arrival home: Comments are closed.
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Kane Faucher
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February 2024
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