Deb and I made the four hour drive up to the east side of Lake Simcoe to dig at the JD Quarry. This was my first time working an active quarry, and it was exciting (and potentially fairly dangerous if you don't properly observe some common sense and safety precautions). It was about a day and a half of rummaging through the rocks on mostly sunny and hot days. But we didn't come away empty-handed!
Deb and me ready on our first day. We arrived shortly after 2 pm. Francie from the Ohio Dry Dredgers and a few of their members were just finishing up. They had just come up from Penn Dixie, and we thank Francie for snapping our picture.
I cannot stress enough that this is an active quarry with regular blasting and areas that are not entirely safe, so there is no messing around here. Full safety equipment (steel-toed boots, hard-hats, and reflective vests are absolutely mandatory), and it requires signing a legal waiver before entering the site. On the right is the entrance.
On the left is just some of the mountainous crush piles. To the right, I'm hauling our wagon full of gear to the uppermost tier flanked by some gullies.
This is a view from the second level overlooking a part of the pit. For a sense of scale, a person standing at that back wall would look little bigger than a dot in this picture. The machines below are quite large. The stratigraphy is mostly Verulam Formation from the Ordovician, with some Bobcaygeon Formation now being dredged out from the base.
Again, a bit tough to make out scale, but the drop here is precipitous. That rock near the top could fall at any time, so it is generally a good idea not to be poking around directly at the base of any of the walls. The usual rule is to keep about no closer than a 45 degree angle from the top of the wall. A lot of loose stuff out there just waiting for any tremor to send it all down - and no hard hat is strong enough to save you from a few hundreds tons of limestone crashing down!
A typical hash plate rich in crinoid and other bits. I tend to either photograph or take home interesting hash plates, and particularly from places I don't get to collect from very often. It gives a sense of the marine bed.
Another hash plate. The Verulam limestone itself is mostly storm-tossed debris as opposed to just the quiet deposition of organisms and sediment over time. In some rocks, you can see the violent wave/ripple of mud having had churned everything.
Two more hash plate with some rich biota. If you look very carefully toward the upper right of the second one, you can pick out the tail piece of a tiny trilobite.
One of the hash plates I brought home of a storm depost of brachiopods and some trilo-bits.
Last hash plate pics, I promise! These are just a few I brought home. The one on the left that is brown fell from the uppermost part of the Verulam and has a good collection of gastropods and a few brachs.
A few members of our crew. From left to right: Roger, Malcolm (with the rock saw), and me. Deb took some video footage of Malcolm in action cutting out a nice multi-plate crinoid slab. Malcolm has been a regular at this quarry for several years, and there is very little he hasn't yet found in terms of the large faunal variety present here.
Malcolm's infamous no-fooling-around rock saw beside a multi-plate of crinoids (picture by Malcolm)
I've been tasked with turning the rock over so that Malcolm can continue his cut to free the crinoids (picture by Malcolm).
Some high-spired gastropods (Fusispira sp) and flatter ones. These weather right out of the rocks. New material depends on the quarry to be blasting out new stuff. Deb and I found that splitting the blocks was not getting us very far - most of the stuff to be found is either weathered out, or appears solely on the exposed parts of the rock. The rock itself alternates between thinly bedded mudstone/shale and very dense encrinal layers. Splitting the mudstone usually had traces or were just blank for us.
Malcolm found this cystoid (Pleurocystites?), and was kind enough to give it to us. I'll try to confirm the species when I update this post.
Crinoid stalk. Certainly not the longest you can find here!
Closeup of a branching bryozoan (Stictopicorella?).
Malcolm tells me that this is a bit of rare one at the site. I found this in the fallen materials on the second level. It is now been confirmed by veteran fossil collectors Kevin K. and Joe K. as the bryozoan, Constellaria - and this may be only third one ever found at this site.
Closeup of a trilobite I pulled from the bottom level. I was really coming for trilobites on this trip, and I was not disappointed. The first one I found in the upper level gullies was a Flexicalymene senaria roller, but this one is a prone and partially/maybe disarticulated one?
One of the most common trilobites in this formation is Isotelus, but full specimens are a bit tricky to find. Just about every rock has bits of them. On the left is a collection of tail pieces, with the one on the extreme left a fairly large (4 inches wide) example that Deb found. On the right are some other pieces, mostly of a genal spine, a hypostome (the mouthpiece, which looks a little like a wrench head) and some head pieces (cranidia).
This I found on the second level: a ventral view (underneath side) of an Isotelus - or what remains of it. You can see the hypostome.
This is a virtually complete Ceraurus missing only its pygidial spikes. It is currently with Malcolm who will be prepping it for me.
Trilobite rollers! I had very much wanted to find a complete Isotelus, and I was not disappointed. The "Kermit" looking one on the left is virtually complete and found lodged in the strata on the second level of the quarry. The one of the far right is a Flexicalymene that I had found minutes upon exploring the site, and the middle one is a Ceraurus sp.
A closeup of the middle one.
I still have a bucket of stuff to go through, and some IDs to put on the finds. In all, it was a fantastic and exciting trip. My thanks to Malcolm for being our gracious and knowledgeable host.
The site boasts a heck of a lot of variety for trilobites alone. Below is a table of identified and described species found in the Verulam Formation by B.A. Liberty (1969) Paleozoic Geology of the Lake Simcoe Area, Ontario. Geological Survey of Canada, Memoirs 355. Since then, Ludvigsen (1979) describes a few others, including Amphilichas (a pygidium of which Malcolm found just this weekend, and is considered a rarity - and never found whole).
Update: I just performed a bit of light cleaning of the rollers and snapped slightly better pictures of them here: