This will be a very tiny whisper of a season opener as I only spent about an hour at a site. This particular site was a bit of an open question after a preliminary scan of the material late last autumn. The material is all Dundee Formation, with different lithologies. My area of focus will be the sandier facies, similar to my out of town rostroconch and Coronura location. Much of the other facies are either a grainstone crinoidal hash with plenty of broken brachiopods and fragmentary fenestrate bryozoans, occasional platycerids, but no apparent trilobite evidence. I recognize this material from a thesis on the Dundee five main facies, but there is likely more localized variety than the thesis might suggest as strata are not necessarily homogeneous over long distances. A February 27 start to the season is not bad, but slightly premature. At the location, there was still considerable snow, at some points thigh-deep. Much of the material is still buried, so I spot-prospected a few rocks to get a better sense of the variety. Material #1: platy, relatively thin-bedded (1-5 cm) with some plasticization and sparsely fossiliferous, with the presence of a few reddish Chonetids. These horizons are mostly blank, but occasionally there will be a bed with a profusion of little more than this tiny brachiopods. Only once, at a different location, did I encounter a trilobite fragment in this material -- Eldredgeops rana pygidium with the same reddish colouring. Material #2: hard, seemingly diagenetically reworked rock with dark grey weathering and internal rock a mottled ashen grey. Has an almost ironstone quality, with rusty vugs. It seems similar to the Guelph Formation. Non-fossiliferous apart from possibly some microfossils. Material #3: Pure mottled chert with some minor styliolitization. Non-fossiliferous. Material #4: Sandy, tidally sorted debris. Fractures according to somewhat undulating beds, or fractures right through fossils. Highly fossiliferous. The most abundant by volume would be brachiopods, largely sorted by size from small to quite large (strophs, spirifers, etc.). Presence of rostroconchs. Very rarely, some bryozoan fragments. No coral. Fossils appear silicified, very similar to the fossiliferous beds of the Amherstburg Fm (Appalachian variant). Trilobites: so far, as I've only been able to crack into one source rock, a single species (Pseudodechenella sp.) represented by two fragmentary librigenae, two cranidia, and one pygidium. Closer inspection under microscope of random samples do not strongly indicate yet the presence of other trilobites, but there are some questionable fragments that might suggest Odontocephalus sp. More time with this material will be needed to confirm that. It is very similar to the material at the out of town rostroconch area, but so far the megafauna are smaller in size and less abundant and diverse in brachiopods. No confirmed gastropod material as of yet. Random sample from source material (#4). Some horizons are certainly "busier" than others in this rock.
I will be returning to this location in the next few weeks as the snows continue to melt. I may not be posting my activity very much this year until after the season is done, nor announce where/when I am going. Keeping things circumspect or secret is quickly becoming a necessity. I will still post on trip finds that may be less "exciting," but it may be a very active year in the field for me. Comments are closed.
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Kane Faucher
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February 2024
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