I spent the last two days in the field, prospecting about nine different spots and coming up fairly empty-handed. I'll chalk this up to practice, and performing due diligence in crossing off possible locations to better identify the productive ones. The first day was close to home, mostly sifting through glacial erratics. These would be a positive and negative of a poorly preserved pygidium in Amherstburg Fm material (and the thinly-bedded, bituminous, crumbly, trilo-poor stuff). Judging by size and other morphological clues, I would label this a Trypaulites sp. The remainder of the day morphed into a challenging three hour hike in the woods, so not much by way of further fossil opportunities for the day. On the second day, Deb and I met up with our dear field comrade to inspect about seven prospective spots beginning with an outcrop section of the Dundee Fm listed in a relatively recent dissertation, and then to the lower Devonian Bois Blanc Fm, and finally to a number of Silurian locations around the Niagara region. I am not one to post location photos anymore for obvious reasons, but it would be hard to place this location and it really doesn't have much to make going back there worthwhile as it is mostly just reefal madness. This is Dundee Fm, and it had absolutely nothing but coral and a few bryozoa. Not even brachiopods. That is a single coral with likely a second branching off it. The length extends to the full frame of the first image. This location is all Bois Blanc Fm, but sadly not the right horizon. In terms of biodiversity, a single brachiopod was found, and two scarce gastropods; everything else was entirely reefal material of corals, crinoids, and bryozoa. Case in point would be these hashes. There is virtually nothing here but the coral, crinoid, and bryozoa salad here. And let's not forget giant coral colonies. The Niagara region is filled with likely hundreds of creeks vermiculating across its landscape. This is one of them. The strata on the right is quite distinct, and not gradational. The yellowish dolostone is likely Lockport Fm. A giant millipede. We did find a good chunk of Rochester shale, but it was entirely blank, and not even the hard-ground limestone lenses had any fossils. This stuff would be brutal to try and work with, as it is wet and just weathers out as chips -- a bit like some intervals in the upper Widder Fm.
This would mark my second big attempt to find anything of interest in the Silurian of Ontario. I've covered a good stretch of it in the north (Bruce Peninsula area) and now the south (Niagara), and have yet to hit proverbial pay dirt. In this recent trip, we covered about 500 km and did not prosper. To my disappointment, I have yet to collect a single fragment of Silurian trilobite from Ontario despite a great deal of research and effort. Perhaps the Silurian is a cursed geological period for me! We do have to keep in mind that just about over half of the Silurian exposed in a narrow band in Ontario from St Catherines up though Tobermory is Salina and Bass Islands -- both unfossiliferous units when this part of the world was salty sabkha. Of the other half that are fossiliferous units, about half or more of those were very poor preservation conditions, and the other half is generally inaccessible. I may just have to cheekily rename the Silurian formations in Ontario along the lines of "and here we have the Bugger All Formation, which lies conformably over the Utter Crap Formation, and contains the Nada, Bupkis, and Blank Members." I will leave the Silurian alone for a bit and refocus on the Devonian and possibly the Ordovician as early as next week. Comments are closed.
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Kane Faucher
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February 2024
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