I felt the need to get out do some collecting today, but not having wheels means I have to keep my trips local for now. London is not known for many things other than my internationally famous cat, and geologically it is post-glacial vomit of sand and erratics several hundred feet deep. That being said, those erratics get sorted and used for all sorts of purposes. Today I visited a spot I had written off five years ago. Upon closer examination with my now more knowledgeable eyes, I bumped into all the Devonian formations up to and including the Dundee, as well as possibly bumping into an Ordovician oddball.
Beds of Leptaena. There were also beds of the common red and white Devonochonetes. This tells me Dundee.
Bits and pieces of Eldredgeops rana and Crassiproetus also says Dundee Fm.
Still on the Dundee kick, here are some wee Coronura aspectans bits.
Appears jet black when opened, but browns when it is exposed to air. It doesn't quite behave like shale, but more like black chert. There were some other segments (not pictured) that looked very much like asaphids.
Just this one rock was mostly sand and purple brachs. That may be an Anchiopsis anchiops impression, so it is possible this is the Oriskany.
Turreted gastropod steinkern, matrix-free Paraspirifer with both valves, a free cheek imprint, and a calcite encrusted nautiloid.
Anchiopsis again, platycerid gastropod, and a bunch of dumpy Anchiopsis.
A Calymene platys pygidium from the Bois Blanc. It may continue into the rock.
The surprise trip-maker was these two Terataspis fragments. What is amazing is they are about a 20-30 minute walk from my house. There were other smaller bits of this species around, but I left them in the field.
So, Bois Blanc, Amherstburg, Lucas, and Dundee formations were represented in this material, of which I only made a six hour surface scan of half the area. A return trip is now a must. I'm not expecting riches, but it is convenient with just enough to keep me interested. And, yes, there were rostroconches, but I didn't take pictures of them... or the crinoidal packstones, the blue cherty corals, the tabulate corals, the zillion other types of brachs and bryozoans, etc.
I can say for certain that I bumped into these trilobites: Anchiopsis anchiops, Crassiproetus crassimarginatus, Pseudodechenella sp. (not pictured), Burtonops cristata (too fragmentary to bother photographing), Coronura aspectans, Eldredgeops rana, Calymene platys, Terataspis grandis. And, possibly that Ordovician oddjob. Of the known, eight species of bugs. Not bad at all.
Unless by dint of some miracle the snows melt away, I think I'll have to call the season. This year has had its highlights and its challenges, and so I would class it as mixed in terms of collecting success compared to 2017. There were some notable challenges this year:
* Late spring and early winter definitely truncated the season.
* An overly hot July and rainy August + scheduling conflicts meant less trips
* My backyard honey hole is pretty much tapped out
* A premium Ordovician collecting site was shuttered to collectors this year
Trilobite collecting diversity was a bit low. Whereas last year I had managed to collect 14 new species, this year's total was only 4. The surge in species acquisitions was mostly supplied through purchases and trades.
Of the trips made this year, a roundup:
* 10 trips to the backyard honey hole with one exceptional find
* A combined 6 days at Penn Dixie (late April, early October)
* My first trip to Deep Springs Road (late April)
* 2 trips to Bowmanville (May and October)
* A combined 15 or so days in the Arkona area
Due to a lack of more local viable sites this year, it meant many of us had to fall back on focusing our efforts on the Widder beds near Arkona, and we managed to excavate extensively this year. The finds were quite good (numerous full Greenops widderensis, placoderm plates, pyritized cephalopods), but somewhat repetitive.
Serious collectors up here in Canada are a little like squirrels. We try to collect as much material as possible for preparation over the winter. Pictured below is 4 of about 5 or so beer flats of material for preparation.
There is more than what is pictured here, but it isn't preparation riches.
Two new areas of focus certainly mark the year. The first has been in the gradual improvement to both my preparation tools/area and skills.
2018 saw the inclusion of that handy trolley, the manifold block for the air tools, a blast chamber my fossil comrade Malcolm made for me, a shop vac, and a new sturdy stool (previously, it was a too-low kitchen chair where the seat was propped up by boxes of rocks with a cushion atop it -- hardly comfortable or convenient). Other stuff include the usual tools of the trade (not all pictured): scrapers, blast media, glues, blades, brushes of all sizes, portable cases, etc. I also now have a nice display cabinet for the trilobites in the living room.
The second area of focus has been extensive reading and research. As I make the transition from "weekend warrior" style fossil hobbyist to something more substantive, I have been consuming a large volume of academic literature on trilobites -- everything from studies on Isoteline hypostome function, biostratigraphy, ecdysis patterns, pathologies and predation, provincial faunalism, eye-blindness trends in evolutionary morphology, microsculpture variation, etc. I also managed to read through the entirety of the trilo-bible, "Treatise O" (the revised Kaesler volume of 1997, sadly not yet including the much-needed two other volumes to round out the rest of the taxonomic Orders). Courtesy of a trilobite worker's kind textual gifts and raiding my own university library, I am effectively training myself to be a subject matter expert on all things trilobite.
IN FOcus: Arkona
Before and after: excavation area #1 (January - October). End of season image does not do much justice to the work done as a lot of debris is already burying the work.
I have been tardy in photographing all the more recent finds from Arkona since my last post about it back in July or August, but there were a few more trips made where I made mostly similar finds as in previous trips this year. Excavation work was extensive this season (and, as I'm the human backhoe, my bar for what I consider extensive is fairly high!). Last season's work became entirely buried by several metres of overburden and debris after the usual processes of winter and the fall of the erosion-resistant widow-makers higher up in the Widder.
Effectively, we had to start from scratch. Pictured above was our first major multi-day foray to get a bite into the cliff from which we could clear out debris and extend benches. It took some doing to locate the productive trilobite layer given that the overburden was obscuring the visible facies, meaning we were flying a bit blind. At the point pictured above, we're still a bit high in the formation by about 1-1.5 metres. Not a bad guess, though, and we were able to work it down and across throughout the season, managing the usual issues of cross-bedding and complicated interlocking of the Widder.
The difference a month makes. In May, Malcolm unlocking new areas. In June from the same vantage point, during Roger's annual visit to Canada, the aftermath of much more removal. We finally hit pay dirt as some remarkable finds were being made at this point after about 7 combined days of clearing and slab hauling.
By the end of spring and into early summer, excavation site #1 is well over 2 metres high, 1-1.5 metres deep, and 10+ metres wide.
Many of us contributed time and muscle to dig this out, with most (solo) visits done by me given that I live the closest to the area and have more ready access. About 12 of us hammered away at this, with a dedicated core of about half of us making repeat visits. By summer, our first excavation was pretty much tapped out unless we wanted to repeat the long clearing process to dig in deeper, which would have meant having to work from the top. We then struck a new claim nearby to the east of the same exposure.
Excavation area #2 was a bit thinner on trilobite pulses. You can see the first area to the far left of Greg.
The slope below the excavation is littered with splits from previous visits. I was able to unlock everything to the right of Greg.
The extent of excavation area #2 just won't fit in a single photo. On this final day, I was able to clear out over 15+ metres to the east. Below the excavation, you can see the massive blocks of the encrinal Hungry Hollow Member. The Widder begins just atop of that and extends to the root of the trees above. The Widder is a strange (and sometimes frustrating) formation where certain faunal intervals repeat, including very dense brachiopod limestone, mushy shale, fossil-poor nodular calcareous shales, and stuff that just weathers to chips and nothingness with poor preservation due to underground water runoff.
In all, it was a substantive amount of focused work to get the site productive again, although I fully expect it to be completely buried by next spring, when the process will have to be started from scratch yet again.
A mostly pyritized and enrolled Greenops widderensis found on my very last trip to Arkona. I have a few rollers to prepare this winter, and such configuration does not lend itself to just basic preparation skills.
FINDS OF THE YEAR
As stated, collecting opportunities were not as plentiful this year due to site closures, weather, and scheduling conflicts. And, of course, the occasional injuries I would sustain from various physical activities. This year, rather than post my best according to taxonomy, some highlights of what made the year special. I am only including here the stuff that was collected, not purchased or acquired as gifts and trades.
Perhaps among my most scientifically significant finds would be this fragmentary cephalic fringe from Odontocephalus sp. found in the imported low-mid Devonian fill (Amherstberg - Bois Blanc - Dundee formations) of my backyard spot. Only a handful of fragments have been reported in the literature in terms of Ontario of a species that is more common in New York deposits. The last significant find of said fragments may be Stauffer's in 1915.
Not just one, but two examples of a new species for me from Bowmanville: Levicerarurus mammilloides. Specimen on the left was prepared by Kevin B., and I have the on the right in my preparation queue (the right eye is in the impression). This is an uncommon cheirurid initially identified by Bill Hessin in 1988, and is restricted to Bowmanville (Hiller Member of the Cobourg Formation). The first one was find in the May trip, and the second in the October trip.
Just a few samples of some placoderm pieces, some of which may be new to science (I still need to deposit them to the ROM along with previous years' finds). The middle one is certainly not new, but a typical placoderm armour plate from Protitanichthys.
This was more a bucket-list item for me. It took three trips to Bowmanville, but I finally found a full Isotelus mafritzae. This one is morph type 'A' due to the presence of the genal spine. I'm still in the process of preparing it, and will be restoring some missing shell. It is only slightly above average size for the species at almost perfectly 100 mm (sag.). I've not seen any specimens that also present such distinct muscle attachment scars on the axis.
Initially just a Greenops widderensis threesome, my friend Kevin's prep skills on my early summer Arkona find produced the surprise of a fourth one. All are enrolled in this gregarious assemblage. As these are body fossils rather than moults, it is likely they enrolled in response to a sudden catastrophic mudslide that effectively buried and smothered them.
Of the four new trilobite species found this year, this would be a short list:
* Odontocephalus sp. (?selenurus) - My thanks to both Scott M. and Dave Rudkin for confirming the ID.
* Leviceraurus mammilloides
* Thaleops sp.
* Flexicalymene croneisi
I was fortunate this year to make new field friends courtesy of their visits to my collecting localities, or to theirs. I was able to meet several new people from The Fossil Forum in person, and many others who are not on the Forum. I made new friends, and cultivated existing ones. In a niche passion such as ours, camaraderie is quickly established (and it helps that we can talk shop without our interlocutors becoming glaze-eyed!).
In the year since I took on a more serious approach to fossil preparation with specialized equipment, I've seen marked improvement in my skills, and I've had an embarrassment of riches in terms of getting guidance from veteran preparators. Some highlights of this year from my "lab":
Although the season has now dictated that I must down collecting tools, it means picking up the preparation tools while dreaming of what new and exciting opportunities for collecting may be in the offing for 2019.
I am reminded of one of Charles Southworth's statements about February, when we stop reminiscing about the collecting season that we've just had and start thinking about the season to come.
Looking ahead to 2019, there are already some new potential opportunities in central New York, in Ontario, and possibly even some digging when I visit Germany next summer. I am also hopeful that some of the sites that have been removed from our list this year will be available next year.
This blog will also not be taking a hiatus just because snow blankets the sites; I will be updating periodically as I acquire new specimens via purchase, and tackle my preparation piles. Stay tuned, and thanks for reading.
Well, it has been a while since the last blog post, but a flurry of recent activity has seen me on multiple days out in the field with fossil comrades doing extensive excavation at our hide-y hole in the Devonian strata. Being bogged down with work has meant that things were quiet on the fossil front for much of the month of June, and a surge of fossil activity here at the end of the month has been exceptionally productive.
Of course, the first few days are about site preparation: digging out overburden, hauling out blocks to dry before splitting, and bench extension while searching for the productive horizon. All that hard work certainly paid off well, and I can safely say that I came away with at least twelve or so full Greenops, a few lovely pyritized cephalopods, and even two very significant examples of placoderm armour.
There were rainy days that made it a slog, but between the group of us (five of us in total, but with people pinching in and out), we moved and split a significant amount of rock.
What now remains is a lot of preparation. The images here are all field fresh, and should come out quite stunning.
Definitely a trip-maker. Finding a complete Greenops widderensis makes for a good day, but this lucky split yielded a multi-plate of three. As these were delicate, and it started raining, I had to douse these in cyanoacrylate quickly so that it would survive the trip home. It is right now in the hands of my friend Kevin who will prepare it and possibly poke around to see if there are any others hiding in the rock.
Loads of trilobites. The last image is of one that has its tail stuck under matrix in the negative, so I'll be gluing it together and prepping it down. Finding so many over a few days meant that we were digging at the right spot.
And yet a few more. The one on the top right is very small and tucked in nicely in the jagged fracture of the bedding plane. The one at the bottom was a very tricky one because the rock wanted to break in every which direction. I had to chisel groove around while another of our crew stabilized it with his hand. A slow process to tap gently, stop, and observe where the crack is going. Sadly, it came out a bit broken on one side, but we wicked the glue on the running cracks and collected any bits of shell that came off to be reapplied during prep.
We were coming across Devonian plant material a bit more often. This stuff is likely fallen pieces that the shore laps up and, after getting water-logged, falls to the sea floor.
Kevin found a real prize in this one. Nicely inflated, well preserved, and pyritized nautiloid.
Not anywhere near as dramatic, but two of my own cephs -- dirty Tornoceras.
A prize find: a good chunk of placoderm plate with that biggest piece being quite thick like a chunk of bone.
And yet another lovely piece of placoderm with full pustular surface. I'm still working away at it slowly on the prep bench, having yet to find where it ends in its companion rock.
In all, a fantastic trip. Great people, great finds. I have a lot of prep work to get to in the coming while.
Readers of the blog may recall a find from my Bowmanville trip back in late May, and the uncertainty of the species. Kevin excellently prepared this beauty, and although it is missing pygidial spines, it is indeed the rarer trilobite Leviceraurus mammilloides.