I've been meaning to photograph some of the great stuff my fossil comrade from Connecticut, Tim, kindly gave me after our big dig in Penn Dixie
First up on the top left are specimens of the Devonian gastropod, Glyptotomariz retispiralede collected from Deep Springs Road, Earlville NY. To the top right is another from the same area, Grammysoidea arcuata. On the lower left are Bembexia sp. gastropods from Morrisville, NY. To the bottom right from Deep Springs Road is Paleozygopleura hamiltonensis
These lovely fish plates are Redfieldius gracilis from the Shuttle Meadow Fm (Jurassic).
These ferns come at a premium now, as they were collected at St Clair, PA where there is no permitted collecting at the site anymore.
The lighting and the faint impressions these generally leave may make this harder to make out, but these are partials and pieces of the fish, Diplurus newarki - a fish my comrade Tim has been studying and collecting for 20 years.
These are coprolites. Yes, fossilized poop. On the left is a coprolite (likely a reptile extruded this one) from the Triassic, while the ones on the right are from the Jurassic. We can learn a lot from studying coprolites, such as diet and environment.
I also have a few pieces of Otozamites latior that do not photograph well. Tim was also kind enough to provide me with two trilobite specimens I did not have (see last blog post).
Shifting gears in the same post, I took a trip to my local honey hole and was entirely skunked. At the very least, I got to be within 7-8 feet of a fairly trusting and majestic bird. I apologize for the poor pixel quality - I only had my iPod with me at the time, and I needed to zoom in a bit as it would have flown away had I approached any closer:
So the afternoon was spent at Hungry Hollow where I collected small bits. The river was too dangerous after all the rainfall to risk going to the usual spots, so we hunkered down in the south pit and plucked weathered stuff out of the Arkona Fm mud-shale. Although I have tons of this stuff, I can't help but to continue picking it up. You never know when someone might want some of it as a gift.
Typical fare from Arkona: an array of crinoid bits, some Aulopora, brachs, Microcyclus ("button coral"), tons of Bactrites, and on the right edge in descending order of size, Tornoceras (or is it Goniatites? - I'm not a cephalopod guy).
Below are some microscope shots to bring out details at 75x:
Deb and I just got back from an intensive four-day dig at Penn Dixie in Buffalo. We were joined by several Fossil Forum members, and it was great to put faces to names. We probably spent about 30 or so hours at the site in total, and cleared well over 150 square feet of virgin matrix of the Windom shale. I was also able to make use of some of my new tools, and by far the most valuable one was the 5 lb wedge. There simply wasn't a slab I couldn't yank out. Apart from just a brief bit of rain on the Saturday, the weather was ideal.
On the first day, when it was just me, Deb, and Tim, we plucked some pretty amazing stuff.
We arrived at the site on Thursday, meeting up with Fossil Forum friend, Tim. The site isn't officially open for the fossil collecting season until the following weekend, but as members we can enter any time. Pictured here is the entrance, and Deb's very great idea of adding a wagon to our collecting kit - which makes ferrying tools from the car to the north part of the pit much easier (and in bringing loads of fossils back to the car after a long day of turning rock into rubble!).
As we approached the productive trilobite pit, some white-tailed dear and wild turkeys in full display.
Below are some shots of our crew/chain gang at work if you ever wondered what it's like to work as a team breaking rock in search of great fossil specimens. Between everybody, we had all the right tools for the job and then some.
On Easter Sunday, while others ate chocolate, it was just me, Deb, and Jay working the pit - but it was by far the most productive day with shale that kept on giving. Quite literally hundreds of trilobites were collected on that day. Easter in 'Murica wouldn't be complete without the percussive sound of the shooting range next door, cuz... 'Murica! Guns!
Below, Jay and I get into the real stuff by clearing out large shale slabs at the productive Smoke's Creek trilobite layer. There's a lot of overburden to remove, and some of those slabs can be stubborn... But stubborn is no match for my reputation of being a human backhoe. There's always a nice and satisfying crunch/pop sound when the slab is freed (and a sound you hope isn't coming from your body!).
Deb splits the shale for the win: a nicely articulated Michelinoceras. We were pulling out a lot of nautiloids that day, as well.
We're absolutely exhausted. It's hard to tell with all that rubble that we made, but that entire circle formed of our bodies and tools represents the removal of a heck of a lot of shale (8" - 15" slabs). We dug right down below the water table. These onlookers had just come by and were curious what we were up to.
A find from the very first day, a rare - yet beat up - Bellacartwrightia whiteleyi. If there is 1 Greenops boothi per 100 Eldredgeops rana, there is probably 1 Bellacartwrightia for every 100 Greenops. The Bellacartwrightia are similar in appearance to the Greenops, but with some key differences in the glabellar furrows, spines along the axial lobe, longer pygidial spikes, and more robust genal spines. A nice catch, if I say so myself!
This is hardly representative of the number of Eldredgeops rana rollers and semi-prones I pulled out. I still have a lot to go through and prep. I estimate that I probably found about 250-300 specimens of E. rana.
This one is kind of funny. On the left is a cephalon covering a full prone, making it look like it is wearing one of those oversized masks. To the right of that is a piggy pile of rollers.
This gorgeous full prone popped right out of the matrix. I stabilized it on site with crazy glue to prevent any accidental breakage in transit.
An example of a full semi-prone still in matrix. Won't need too much prep to bring it out, but there may be two rollers also buried in here that need some preparation work.
These two pictures hardly do justice to the number of trilobites that still need some prep attention. Some of them are quite large, too. This will keep me busy for a while!
A fairly representative array of brachiopods one can find at Penn Dixie.
This is an interesting one as it has a black trilobite on top of a brown one. If I can prep it right, it should really stand out and reveal some of those chromatophores.
Top row: a crinoid calyx and a horn coral with encrusted calcite. Bottom row: three fairly well preserved Platyceras.
The group dig provided our members with a great opportunity to trade finds native to our respective areas. Tim very generously gave me a big box of incredible stuff (fish, gastropods, trilobites, ferns, coprolites, etc.) that I will photograph and post as a separate blog entry. For now, I'll post a few new trilobite species for my collection that Tim has given me. This one is a Phalangacephalus dentatus.
And these are fragments of Dipleura dekayi, a very interesting Devonian trilobite. These were collected by Tim at Deep Springs Road, NY.
This has been a memorable and possibly the best fossil collecting trip I've ever been on. Meeting new people, working together to haul rock, sharing our finds, perfect weather, and an abundance of quality specimens really made this a remarkable one. The aftermath - apart from nursing a very sore body! - is to process the finds I have. I expect to be posting a few more entries on the finds I've yet to prep and photograph. Thanks for reading!
I actually didn't anticipate posting again until after the upcoming dig at Penn Dixie, but two consecutive days of collecting at my riprap hill nearby has brought some excitement into the collection.
For some many years of collecting from this place, I knew a lot of that material was shipped in. My assumption was that it was more locally sourced (and thus mostly Dundee Formation). Many of the fossils I was pulling from there are reported as part of the Formation. Until I found one that wasn't. But also peculiar were the fossils I was NOT finding that are typical of the Dundee. Not even typical of the Hamilton Group (Arkona, Widder, etc.). I guess I was blinded by what I assumed to be true as opposed to facing the cold, objective truth as evidenced by the biota.
Yesterday I found this:
And a closer view:
So, fairly eroded away, leaving only a cast/mold of a part of the cephalon of this trilobite. But it is a whopper. I don't really find Devonian trilobites approaching this size (Ordovician ones, yes). So I posted it on the fossil forum, and our resident trilobite expert Scott weighed in and said it was either Trypaulites calypso or Coronura aspectans, both of which are recorded in the Dundee Formation. There isn't a lot of diagnostic details to go on, but you can make out the distinctive occipital ring and the deep furrow on the lower left of the cephalon. So, we know it could be one of these two dalmanatid trilobites, right? Hold on...
I spent another four hours today carefully taking on any rock on the hill, splitting it, and seeing if anything interesting might come up. As I've pulled Basidechenella from there in the past, I was hoping for more than just another pygidium. There was this one greyish, round rock about the size of a softball lying there. I wasn't going to bother with it as I thought it would just be another blank, or just one of those dense balls of largely erosion-resistant rocks where you have to bring out the big guns to split it and find only a tiny smattering of brachiopods. But I was already sitting in the gully breaking rocks, not in a hurry to get back up, so I thought, "why not while I'm here?" So glad I did, because this was the rock that became the key for determining the origin of many of the rocks on this hill - and thus explains the biota.
Without double-checking, I thought, "ok, another Trypaulites specimen. That's pretty lucky to find two in less than 24 hours." I assumed from my patchy memory of looking at a Trypaulites in the Ludvigsen volume. I really should have looked more closely to confirm that assumption. I was still tickled pink to find another specimen. But when I posted it, Scott chimed in again by saying it was NOT a Trypaulites. It was instead a Anchiopsis anchiops, and those only occur in the Bois Blanc Formation.
The only significant outcrops of Bois Blanc are hundreds of kilometres away, in the Niagara escarpment. So what the heck was it doing here in London, Ontario? There is no doubt on the ID of this one. I checked the literature and, Scott was bang on as usual. Scott then revised his earlier ID on the big cephalon above and said it was also Anchiopsis, but missing the distinctive occipital spine. Here are the images Scott presented for comparison with what I found:
So I went back and took a longer look at the several finds I've made in this location over the past four years. I compared those to what was listed in the Bois Blanc, and there they all were. What didn't tip me off is that there is a great deal of overlap of species between the Bois Blanc, Dundee, and other formations in the Devonian. For example, the trilobites Eldredgeops rana and Basidechenella sp. appear in both formations. I had reasonably assumed that the materials delivered and dumped to make this hill would be more locally sourced, as that would seem more economical. And thus I stuck with my first assumption that everything I pulled out of the hill was likely Dundee Formation or thereabouts. But the presence of the Anchiopsis throws all of that out, as it ONLY appears in the Bois Blanc. So, in sum, I am collecting from the Niagara escarpment pretty much in my backyard. The stratigraphy is as follows in descending order of age:
The Bois Blanc is the second oldest Devonian strata, underlain by the Oriskany. According to Armstrong and Dodge (2007):
"The Oriskany Formation is disconformably overlain by the grey to brown, very cherty, fossiliferous, argillaceous limestones and dolostones of the Bois Blanc Formation (Uyeno et al. 1982). Thin beds of glauconitic quartz sandstone that occur near the base of the Bois Blanc are assigned to the Springvale Member (this member is not shown on OGS maps). The Bois Blanc Formation outcrops and subcrops in a narrow belt from Fort Erie on the Niagara River to MacGregor Point on Lake Huron. North of Norfolk County outcrops of this unit are sparse."
According to Ludvigsen (1979), there are five major genera of trilobites in the Bois Blanc: Phacops [Eldredgeops] rana, Basidechenella sp, Crassiproetus sp, Anchiopsis anchiops, and Terataspis grandis. I have so far collected three of the five.
I could dare to dream in finding, say, one of the most famous of all trilobites - a monster at over 50 cm or more, for which only fragments have been collected, Terataspis grandis:
I'm not saying I will find one, only that it is now possible. The probability of finding one is entirely different story.
So I've now had to reassess my assumptions that have been engrained for years, and I am delighted to be wrong and to welcome yet another new species into my collection - quite a few with the season just beginning. I'll sign off with a pic of some other finds of the day:
As temperatures slide into spring, the semester drawing to a close, I am back out in the field ending my cabin fever. Pictured here are a few finds from one of my nearby honey holes, some of which I've found in the past but did not post pictures of.
Pictured above and in the next two pictures, are pieces of a coral. It has been identified as likely Triassic or Jurassic in origin. How it came to be in a largely Devonian area is a mystery to me!
Here is a bigger chunk of the same coral. The shell type at the top is likely oyster.
This one was found along the Thames River at the university. Initially I thought this might be a transversely placed Megastrophia sp. brachiopod showing only the hinge, but it just doesn't seem to fit. Could it be a worm tube? Seems a bit too straight to be one. A mystery!
Above: a picture of the "riprap hill". Below: typical littoral.
Simple brach hash.
Nothing wow here: a chunk of tabulate coral, two brachs, a worn piece of Aulopora, and a general marine hash.
Worn gastropods. Hormotoma type on the left.
Leptaena sp. brachiopod, red on brown-grey matrix.
Hash plate with trilobite pygidia.
Fragments of two new species of trilobite for me. On the left is a piece of pygidium from Trypaulites calypso, found along the Thames River. According to Ludvigsen (1979), no specimen of this species has been collected in Ontario, although the equivalent strata elsewhere would suggest it should appear. This * might * be the first confirmed find of this species in the Dundee Formation in London (very exciting!). On the right is a partial cephalon impression of Basidechenella sp. to go along with a few of the pygidia that I sometimes pull from this area.
This now brings my trilobite tally to 10: Eldredgeops rana, Greenops widderensis, Greenops boothi, Basidechenella sp., Trypaulites calypso, Flexicalymene ouzregui, Pseudogygites latimarginatus, Triarthrus eatoni, Proetus sp.
This year, if time and travel permit, I hope to add a few more - particularly from the Ordovician. Stay tuned, for I'm returning to Penn Dixie this week for a multi-day dig. For now, here is a pic of me and the missus from last October that the PD folks put up on their website: