With the ending of spring and the arrival of summer, we've seen a blast of heat over the last while which makes collecting a bit of a challenge. Most collecting areas seem to be in full sun with no shade, and so I sometimes opt to go collecting in the mornings when it is slightly cooler. Trips to the hill out back have yielded some interesting and pleasant surprises. The hill (and pit) is composed of mixed Devonian deposits dumped there from around the region for the purposes of hill-building, so it is a mixed bag. Here we see a closeup of a prone Eldredgeops rana trilobite in a state of fairly good preservation. I spotted only a sliver of it in the rock and carefully went about splitting it to reveal what was inside. The lack of adequate laminations in the rock mean that there are virtually no convenient bedding planes to exploit, and thus the probability is very high that the rock will split in ways that can cleave right through the specimen. And that was the case here, resolved by binding the two pieces together. I've also found my share of a few weathered or semi-weathered out rollers, but they are sadly headless. Pygidium moults and shards of cephalon abound. Pictured here is the coral Syringopora. I generally pass corals and bryozoans over, but the weathered out lattice-like fenestrations were unique to any of the other corals I've seen in the area. My thanks to TFF user TqB for taking the initiative in showing this to Adrian Bancroft, an expert in bryozoans, to confirm identification that this is indeed a coral of the Syringopora species. Among my other finds in repeated trips to the hill, I don't have much more that is picture worthy. Having exhausted all the exposed, well-laminated shales, I've moved on with my trusty claw hammer and chisel to split some of the denser rocks - and the presence of trilobites inside makes it a thrilling rock lottery of sorts... And a lottery it certainly is, with about the same odds. What the site needs is to be turned over a bit to expose some of the rock buried under the dirt and clay, while some other areas will be better exposed come autumn when the weedy overgrowth thins out. Another trip here in town, plus threading some fossil hunting into our week-long Ottawa trip, mark our new finds. We scouted along the Ottawa and Rideau Rivers, and for me it was a bit of a homecoming. Much of the area is dominated by the Billings Formation, composed of either rich black or brown highly fissile and fossiliferous Ordovician shale. The typical biota includes trilobites, nautiloids, brachiopods, graptolites, crinoids, etc. Pictured here on the left is a fairly substantially sized pygidium of the trilobite Pseudogygites latimarginatus, while on the right is a hash-plate of fragments from the same species. It is very challenging to find a fully intact specimen, and far more common to find the moults or bits of cephalon, thoracic spines, pleura, and pygidium. This strata also shares with another branch of trilobites, Triarthrus Another very busy hash-plate, pulled from the Rideau River near Strathcona Park. As we didn't think to bring tools on our trip, I had to channel my inner neanderthal by dead-lifting a 220lb rock and dropping it on another rock in order to split this one open. Note on the lower left: tantalizingly close to being a full specimen. "Here Lie The Trilobites - Rest in Peace." Well, to my mind it does almost appear like a grave marker. Another fairly busy and impressive hash-plate pulled from the same small cluster of large rocks along the Rideau. The prize find goes to Deb for finding a nearly fully intact cephalon of Pseudogygites. In fact, she was the first between us to pull a pygidium as well as spotting the glabella of Triarthrus. On the right is a few more assorted pieces we selected to take with us, leaving the rest behind. Our luggage was heavy enough without the additional rocks.
And that's all for today. I am still lightly prepping a few specimens that I pulled from the nearby hill, and there have been some welcome surprises. Until then... |
Kane Faucher
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February 2024
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