A day’s excursion into the Middle Devonian of western New York

August 7th, 2015

1 Wanakah at Buffalo CreekLOCKPORT, NEW YORK (August 7, 2015) — Today Andrej Ernst and I were able to join Brian Bade and his friends on a collecting trip up Buffalo Creek in Erie County, New York. Our goal was simply to look for interesting fossils in the Wanakah Shale Member of the Ludlowville Formation (Middle Devonian) and enjoy the fellowship of fossil enthusiasts. Success on both counts. It was a great day, and rather fun wading through the cool waters of the creek as we examined the shale on the banks.

2 Wanakah TrilobiteHere is an external mold of a trilobite in the soft Wanakah Shale. An external mold is an impression of the exterior of the organism. If you look at this upside-down it pops into reverse relief! This fossil is not recoverable because it would break into bits with any attempt to hammer it out. Andrej and I found plenty of bryozoans here, along with other cool fossils.

3 Bethany Center Centerfield LimestoneAs a bonus we also were able to visit the Bethany Center exposure of the Centerfield Limestone, also Middle Devonian. There isn’t much left of the exposure, as you can see, but we still found numerous encrusting organisms (sclerobionts) on brachiopods and the abundant rugose corals. We also got plenty of sun here.

Into the Niagara Gorge

August 6th, 2015

1 Lewiston-Queenston Bridge 080615LOCKPORT, NEW YORK (August 6, 2015) — It holds one of the strongest river currents in the world, the gorge of the Niagara River below Niagara Falls. That tremendous flow has cut a deep canyon through the Silurian rocks of the region, providing a superb opportunity for geologists to see the local stratigraphy and paleontology. Today our team walked into the gorge from Lewiston, New York, to explore the section. Carl Brett was our guide. Above is a view of the gorge at the Lewiston-Queenston Bridge that joins the USA on the right with Canada on the left. The forests are plenty dense, but there are rocks in those steep walls.

2 Gorge trailWe hiked along the Gorge Trail on the USA side upriver from Lewiston. The trail is actually an old road built for transport of construction materials used for the hydroelectric dams upriver.

3 Gorge block 080615We learned most of the geological context by examining fallen blocks along the trail. This was an interesting way to see the stratigraphy because the different formations dropped blocks randomly along the path.

4 AE080615I tried to get a surreptitious picture of my German colleague Andrej Ernst.

5 Grimsby crossbedsThe Grimsby Formation (Lower Silurian, Llandoverian) is a sandstone that has numerous sedimentary structures, including nice cross-sets.

6 Kinneyia Grimsby Niagara GorgeAndrej found this nice specimen of an enigmatic feature called Kinneyia. It may be a function of gas build-up underneath microbial mats on the ancient seafloor. I’ve always called it “elephant skin”.

7 Niagara Gorge section 080615A view of the gorge wall above us.

8 Rochester collecting Niagara GorgeWhen the trail reached the Rochester Shale, we spent some time searching it for fossils. The most common finds were cystoids (especially Caryocrinites) and the odd coronoid Stephanocrinus.

9 Andrej Carl 080615Andrej Ernst and Carl Brett on the Rochester Shale outcrop in the Niagara Gorge. Andrej noted many neglected bryozoans in the fossil fauna exposed here.

10 Sir Adam Beck Hydroelectric Generating StationsOur final stop was opposite the Sir Adam Beck Hydroelectric Generating Stations built on the Canadian side of the gorge. It is an awesome feat of engineering, and a prodigious amount of concrete.

We had an excellent time in the Niagara Gorge. I was at last able to see some of the nuances of Silurian stratigraphy that Carl Brett was explaining. As you can see, the weather was ideal.

We said goodbye to Carl at the end of the day as he departed for fieldwork in nearby southern Ontario.


Wooster Geologist in New York

August 5th, 2015

1 Calebs Quarry 080515LOCKPORT, NEW YORK (August 5, 2015) — What looks like an ordinary commercial quarry above is actually quite unusual. It is an excavation done entirely by amateur paleontologists (“citizen scientists”) to collect and preserve fossils from the Rochester Shale (Upper Silurian, Wenlockian). The story of Caleb’s Quarry is well told in the linked American Museum of Natural History article. It is near Lockport, New York, and one of the most famous fossil sites in the region. I’m lucky to be here.

This late summer expedition to New York is to help my German friend Andrej Ernst (University of Hamburg/University of Kiel) collect bryozoans from the Rochester Shale. This bryofauna is inadequately described for phylogenetic and biogeographic analyses, so Andrej has a grant to do the deed from outcrop sampling to preparation, analysis and publication. While assisting Andrej, I am also scouting out new localities for future geology Senior Independent Study projects at Wooster. We will be in Niagara and Erie Counties for a week doing this work.

2 CarlCalebsAbsolutely critical to the project is the field advice and direction of Carl Brett (University of Cincinnati). Carl is without peer when it comes to many paleontological and geological topics, but for the Silurian of New York he is one of the gods. Carl grew up in the region and has been studying the rocks and fossils since he was a young teenager. He gave us two days of magnificent stratigraphic instruction, and he introduced us to the amateur team digging at Caleb’s Quarry. We were also joined for three days by Brian Bade, a citizen scientist from Ohio with an extraordinary passion for fossils, along with deep knowledge and appreciation for how science works.

3 FredandCarlCalebsFred Barber, one of the excavators at Caleb’s Quarry, is here showing Carl Brett magnificent crinoids collected from this locality.

4 Crinoid Calebs 080515The gray shale matrix is homogenous and soft enough to be removed from the fossil by an expert preparator. This crinoid shows outstanding preservation down to the pinnules on its arms.

5 Bryozoan Calebs reconstructedOf course, Andrej and I are most interested in the bryozoans from Caleb’s Quarry. Here is a beautiful specimen that has been carefully reconstructed.

6 StriispiriferCalebsI found these brachiopod-rich beds intriguing. Striispirifer is a new name to me.

7 DalmanTriloCalebsTrilobites are always the stars of Paleozoic fossil sites like this. While we were at the quarry we watched one of the excavators (Kent Smith) unearth this gorgeous specimen. I believe it is Dalmanites limulurus.

8 ChondritesCalebsThe trace fossils here are very interesting. There may be project possibilities with this ichnofauna because of the diversity present at the quarry and the bedding plane exposures. This is the trace fossil Chondrites.

9 Jungle Jeddo tributaryAfter our quarry visit today we then stopped at some other exposures of the Rochester Shale. This scene shows what fieldwork is like without quarries and roadcuts! We are here along a tributary of Jeddo Creek, at the top of Lewiston Member B of the Rochester Shale. Hard to tell, eh?

10 Brian Jeddo Tributary Lewiston BHere Brian Bade is examining a deeply weathered section along the creek. Years ago Carl Brett took advantage of this disaggregation of the Rochester Shale to sieve the sediment for small fossils. He has generously given us the “washings” from this cut, which represent months of his work as a graduate student. They are loaded with tiny bryozoan bits, along with many other taxa.

11 Cherokee UnconformityWe ended the day with a look at several other outcrops in the Lockport area. The impressive contact here between the massive sandstone and the underlying red shales is called the Cherokee Unconformity. It is a megasequence boundary correlated across most of North America. It was thought until recently to be the Ordovician-Silurian boundary, but now all you see in this image is considered latest Ordovician.


Wooster’s Fossil of the Week: A conulariid revisited (Lower Carboniferous of Indiana)

July 31st, 2015

Conulariid03 585

This summer I’ve been updating some of the photos I placed in the Wikipedia system (check them out here, if you like; free to use for any purpose). I was especially anxious to replace a low-resolution image I had made of an impressive conulariid (Paraconularia newberryi) from the Lower Carboniferous of Indiana. The new version is above. Since I used the same specimen as a Fossil of the Week exactly four years ago to the day, I thought I’d take advantage of a slow summer and update that earlier text for this week:

I have some affection for these odd fossils, the conulariids. When I was a student in the Invertebrate Paleontology course taught Dr. Richard Osgood, Jr., I did my research paper on them. I had recently found a specimen in the nearby Lodi City Park that was so different from anything I had seen that I wanted to know much more. I championed the then controversial idea that they were extinct scyphozoans (a type of cnidarian including most of what we call today the jellyfish). That is now the most popular placement for these creatures today, although I arrived at the same place mostly by luck and naïveté.

The specimen above is Paraconularia newberryi (Winchell) found somewhere in Indiana and added to the Wooster fossil collections before 1974. A close view (below) shows the characteristic ridges with a central seam on each side.

Conulariid01 585Conulariids range from the Ediacaran (about 550 million years ago) to the Late Triassic (about 200 million years ago). They survived three major extinctions (end-Ordovician, Late Devonian, end-Permian), which is remarkable considering the company they kept in their shallow marine environments suffered greatly. Why they went extinct in the Triassic is a mystery.

ConulataThe primary oddity about conulariids is their four-fold symmetry. They had four flat sides that came together something like an inverted and extended pyramid. The wide end was opened like an aperture, although sometimes closed by four flaps. Preservation of some soft tissues shows that tentacles extended from this opening. Their exoskeleton was made of a leathery periderm with phosphatic strengthening rods rather than the typical calcite or aragonite. (Some even preserve a kind of pearl in their interiors.) Conulariids may have spent at least part of their life cycle attached to a substrate as shown below, and maybe also later as free-swimming jellyfish-like forms.

It is the four-fold symmetry and preservation of tentacles that most paleontologists see as supporting the case for a scyphozoan placement of the conulariids. Debates continue, though, with some seeing them as belonging to a separate phylum unrelated to any cnidarians. This is what’s fun about extinct and unusual animals — so much room for speculative conversations!


Driscoll, E.G. 1963. Paraconularia newberryi (Winchell) and other Lower Mississippian conulariids from Michigan, Ohio, Indiana, and Iowa. Contributions from the Museum of Palaeontology, The University of Michigan 18: 33-46.

Hughes, N.C., Gunderson, G.D. and Weedon, M.J. 2000. Late Cambrian conulariids from Wisconsin and Minnesota. Journal of Paleontology 74: 828-838.

Sendino, C., Zagorsek, K. and Taylor, P.D. 2012. Asymmetry in an Ordovician conulariid cnidarian. Lethaia, 45: 423-431.

Van Iten, H.T., Simoes, M.G., Marques, A.C. and Collins, A.G. 2006. Reassessment of the phylogenetic position of conulariids (?Vendian–Triassic) within the subphylum Medusozoa (Phylum Cnidaria). Journal of Systematic Palaeontology 4, 109–118.


Wooster’s Fossil of the Week: A calcareous sponge from the Lower Cretaceous of England

July 24th, 2015

Raphidonema faringdonense 070715a 585One of my favorite fossil localities is a gravel pit in Oxfordshire, England. Gravel pits are not usually good for fossil collecting given their coarse nature and high-energy deposition, but the Lower Cretaceous (Aptian) Faringdon Sponge Gravels are special. They are tidal gravels sitting unconformably over Jurassic rocks that have an extraordinary diversity and abundance of marine fossils, both from the Cretaceous and reworked from the Jurassic below. I have previously described in this blog bored cobbles, bryozoans, ammonites and a plesiosaur vertebra from this unit. Above is one of the most characteristic fossils from Faringdon, the calcareous sponge Raphidonema faringdonense (Sharpe, 1854).
Raphidonema faringdonense 070715b 585This is a view of the upper surface of this sponge. Like most sponges it was a filter-feeder sitting stationary on the seafloor. This one was probably attached to a cobble in the gravel. It is in the Class Calcarea because it has a fused network of calcitic spicules making up its skeleton. This is why it has remained a very resistant, rigid object long after death. It probably spent some time rolling around in those gravels with the tidal currents.
Sophie Faringdon 2007The Faringdon Sponge Gravels are a member of the Faringdon Sand Formation. They are cross-bedded gravels that have been mined for construction purposes since Roman times. Above is Wooster Geologist Sophie Lehmann (as a student) when she and I visited one of the gravel pits in 2007. For the record, this sponge comes from the Red Gravel, 5.5-8.5 meters above the disconformity with Oxfordian limestones, in the Wicklesham gravel pit on the southeast edge of Faringdon, Oxfordshire (51.647112° N, 1.585094° W).

after Maull & Polyblank, photogravure, circa 1856

Daniel Sharpe FRS (1806-1856) named Raphidonema faringdonense in 1854. He was born in Marylebone, Middlesex, England. His mother died shortly after his birth and he was raised by his uncle Samuel Rogers, a literary figure of some merit. He entered the mercantile business as an apprentice when he was 16, and he stayed connected with trading the rest of his life. His first research as a geologist (and this was very early in the discipline of geology) was examining geological structures around Lisbon, Portugal. He then studied the strata of north Wales and the Lake District of England. Sharpe was an early opponent of Adam Sedgwick in a dispute over the Cambrian, which brought him some notoriety among English geologists. His most prominent geological work was sorting out what rock cleavage meant in regard to stress and strain, using distorted fossils as part of his evidence. He died as the result of a riding accident in 1856, shortly after he had been elected president of the Geological Society of London.

Sorting out the taxonomic history of Raphidonema faringdonense is more complex than I would have expected for such a simple fossil. I’m using the most common version of the name, but we also see “farringdonense“, “faringdonensis” and farringdonensis“. (I know. Who worries about such things?)
Manon farringdonense Sharpe figuresManon farringdonense description 1854Above are Sharpe’s original figures of Raphidonema faringdonense, along with his description (and the nice bryozoan Reptoclausa hagenowi below). We can see that he spelled the species name with a double r in keeping with a common spelling of the village’s name then. I don’t know when we lost one of those letters.

Just to add to the complexity, Raphidonema is also the genus name of a filamentous green alga. Since it is not an animal, though, there is no legal problem with having the name also refer to a sponge. (There should be a rule against such homonymy, but there’s not.)


Austen, R.A.C. 1850. On the age and position of the fossiliferous sands and gravels of Faringdon. Quarterly Journal of the Geological Society of London 6: 454-478.

Lhwyd, E. 1699. Lithophylacii Britannici Ichnographia. 139 pp. London.

Pitt, L.J. and Taylor, P.D. 1990. Cretaceous Bryozoa from the Faringdon Sponge Gravel (Aptian) of Oxfordshire. Bulletin of the British Museum, Natural History. Geology 46: 61-152.

Sharpe, D. 1854. On the age of the fossiliferous sands and gravels of Farringdon and its neighbourhood. Quarterly Journal of the Geological Society of London 10: 176-198.

Wilson, M. A. (1986). Coelobites and spatial refuges in a Lower Cretaceous cobble-dwelling hardground fauna. Palaeontology, 29(4), 691-703.

Wooster’s Fossil of the Week: A coiled nautiloid from the Middle Devonian of Ohio

July 17th, 2015

Goldringia cyclops Columbus Ls Devonian 585The above fossil is a nautiloid cut in cross-section, showing the large body chamber at the bottom and behind it to the left and above the phragmocone, or chambered portion of the conch (shell). It is a species of Goldringia Flower, 1945, found in the Columbus Limestone (Middle Devonian, Eifelian) exposed in the Owen Stone Quarry near Delaware, Ohio. It is a nice specimen for both what it shows us about a kind of nautiloid coiling and for clues to its preservation.

This specimen was originally labelled Gyroceras cyclops Hall, 1861. In 1945, Rousseau Flower designated this taxon the type species of Goldringia. I can’t tell if we really have G. cyclops here or some other species, so I’m leaving it at the genus level. The old name lingers, though, in the term for this kind of open coiling: gyroceraconic. It is one of the earliest examples of the nautiloids having the phragmocone positioned above the body chamber, presumably for stable buoyancy.
Pentamerid embedded 071315I like the clues to the early history of this conch after death. The chambers are entirely filled with sediment, a fossiliferous micrite. You can see places where the original shell was broken and larger bits infiltrated, like the whole brachiopod shown above. This brachiopod appears from its cross-section to be a pentamerid. Also visible are strophomenid brachiopods and gastropods.
Winifred GoldringRousseau Hayner Flower (1913–1988) described Goldringia in 1945. He doesn’t directly say who he named it after, but he thanks “Dr. Winifred Goldring of the New York State Museum” in the acknowledgments. We can tell Flower’s story later (and it’s a good one), but this gives us a chance to introduce Winifred Goldring (1888-1971). She was the first paleontologist to describe the famous Gilboa fossil flora (Devonian) in upstate New York, and she was the first woman State Paleontologist of New York (or anywhere, for that matter). (Now there is Lisa Amati in this prestigious position. Congratulations, Lisa!) Goldring grew up near Albany, New York, one of nine children in a very botanical family. She graduated from Wellesley College in 1909 with a bachelor’s degree in geology (very unusual for a woman at the time). She stayed at Wellesley to earn a master’s degree (1912). She also taught geology courses at Wellesley. In 1913 she studied geology at Columbia University with the famous Amadeus Grabau. In 1914, Goldring joined the scientific staff at the New York State Museum as a “scientific expert”. She worked her way up through the many ranks there to become State Paleontologist in 1939. She is best known as a paleontologist for her work with the fascinating Gilboa fossil forest, bringing her early upbringing by botanists to full circle. Along the way she was the first woman president of the Paleontological Society (in 1949) and vice-president of the Geological Society of America (in 1950). A hero of paleontology.


Flower, R.H. 1945. Classification of Devonian nautiloids. American Midland Naturalist 33: 675–724.

Goldring, W. 1927. The oldest known petrified forest. Scientific Monthly 24: 514–529.

Koninck, L.G.D. 1880. Faune du Calcaire Carbonifere de la Belgique, deuxieme partie, Genres Gyroceras, Cyrtoceras, Gomphoceras, Orthoceras, Subclymenia et Goniatites. Annales du Musee Royal d‘Histoire Naturelle, Belgique 5: 1–333.

Wooster’s Fossil of the Week: A small lobster from the Lower Cretaceous of North Yorkshire, England

July 10th, 2015

Meyeria ornata fullMae Kemsley (’16) found this little beauty during her Independent Study fieldwork last month on the Speeton Cliffs of North Yorkshire. It is Meyeria ornata (Phillips, 1829), a decapod of the lobster variety, from the Speeton Clay. It is relatively common in Bed C4, so much so that it is referred to as “the shrimp bed”. Mae is the only one of our team of four who found one, though, so it is special to us. The above is a lateral view, with the head to the left and abdomen on the top of this small concretion.
Dorsal Meyeria ornataHere is a dorsal view looking down on the abdominal segments.
Screen Shot 2015-07-01 at 9.14.03 PMSimpson and Middleton (1985, fig. 1b) have this excellent diagram of Meyeria ornata in life position. The scale bar is one centimeter. “Details of pleopods, third maxillipeds and first antennae of M. ornata unknown. Dashed line represents length of extended abdomen. Symbols: a branchiocardiac groove; c postcervical groove; e cervical groove; m3 third maxilliped; p pereiopod; pi pleopod; t telson; u uropods; x ‘x’ area; r rostrum; al first antennae; a2 second antennae; ar antennal ridge; sr suborbital ridge; 1,2,3. branchial ridges.”

According to Simpson and Middleton (1985), Meyeria ornata actively crawled about on the muddy substrate like modern lobsters. They did not have true chelae (large claws), so they were likely scavengers in the top layers of the sediment rather than predators.

3 Mae working 060915Mae at work.


Charbonnier, S., Audo, D., Barriel, V., Garassino, A., Schweigert, G. and Simpson, M. 2015. Phylogeny of fossil and extant glypheid and litogastrid lobsters (Crustacea, Decapoda) as revealed by morphological characters. Cladistics 31: 231-249.

M’Coy F. 1849. On the classification of some British fossil Crustacea with notices of new forms in the University Collection at Cambridge. Annals and Magazine of Natural History, series 2, 4, 161-179.

Phillips, J. 1829. Illustrations of the geology of Yorkshire, Part 1. The Yorkshire coast: John Murray, London, 184 p.

Simpson, M.I. and Middleton, R. 1985. Gross morphology and the mode of life of two species of lobster from the Lower Cretaceous of England: Meyeria ornata (Phillips) and Meyerella magna (M’Coy). Transactions of the Royal Society of Edinburgh: Earth Sciences 76: 203-215.

Wooster’s Fossils of the Week: An Upper Ordovician cave-dwelling bryozoan fauna and its exposed equivalents

July 3rd, 2015

1 Downwards 063015This week’s fossils were the subject of a presentation at the 2015 Larwood Symposium of the International Bryozoology Association in Thurso, Scotland, last month. Caroline Buttler, Head of Palaeontology at the National Museum Wales, Cardiff, brilliantly gave our talk describing cryptic-and-exposed trepostome bryozoans and their friends in an Upper Ordovician assemblage I found years ago in northern Kentucky. They were the subject of an earlier Fossil of the Week post, but Caroline did so much fine work with new thin sections and ideas that they deserve another shot at glory. We are now working on a paper about these bryozoans and their borings. Below you will find the abstract of the talk and a few key slides to tell the story.


Trepostome bryozoans have been found as part of an ancient cave fauna in rocks of the Upper Ordovician (Caradoc) Corryville Formation exposed near Washington, Mason County, Kentucky.

Bryozoans are recognized as growing from the ceiling of the cave and also from an exposed hardground surface above the cave. Multiple colonies are found overgrowing one another and the majority are identified as Stigmatella personata. Differences between those growing upwards and those growing down from the roof have been detected in the limited samples.

The colonies have been extensively bored, these borings are straight and cylindrical. They are identified as Trypanites and two types are recognised. A smaller variety is confined within one colony overgrowth and infilled with micrite. In thin section it is observed that the borings follow the lines of autozooecial walls and do not cut across. This creates a polygonal sided boring, suggesting that the colonies were not filled with calcite at the time of the boring. The second variety has a larger tube size and its infilling sediment has numerous dolomite rhombs and some larger fossil fragments including cryptostomes, shell and echinoderm pieces. These cut through several layers of overgrowing bryozoans. Some of the borings contain cylindrical tubes of calcite similar to the ‘ghosts’ of organic material described by Wyse Jackson & Key (2007).

Very localised changes in direction of colony growth due to an environmental effect are seen.

Bioclaustration in these samples provides evidence for fouling of the colony surface, indicating that the bryozoans overgrew unknown soft-bodied organisms.


Wyse Jackson, P. N., and M. M. Key, Jr. (2007). Borings in trepostome bryozoans from the Ordovician of Estonia: two ichnogenera produced by a single maker, a case of host morphology control. Lethaia. 40: 237-252.

2 Title 0630153 Location 0630154 Strat position 0630155 hdgd up 0630156 hdgd down 0630157 Growth up 0630158 Growth down 0630159 Stigmatella 06301510 Cartoon 06301511 Boring A 06301512 Boring B 06301513 Ghosts explanation14 Ghosts 06301515 Overgrowths 06301516 Further questions 063015

Link to posts from Wooster Geologists in the United Kingdom in June 2015

June 29th, 2015

11 Mae Meredith Filey BriggI spent 25 days in England, Scotland and Wales this month, 12 of them with these two happy Senior Independent Study students, Mae Kemsley (’16) and Meredith Mann (’16) — dubbed “Team Yorkshire”. We had to delay our blog posts until today. You can see all of them by clicking the UK2015 tag. It was a spectacular expedition. Thanks again to Paul Taylor, Jen Loxton, Joanne Porter, Tim Palmer, Patrice Reeder and Suzanne Easterling for the parts they played in this adventure. Thank you as well to Mae and Meredith who were not only sharp field paleontologists, they were great companions as well. They are shown above on the tip of Filey Brigg in North Yorkshire. (N54.21560°, W00.25842°; Google Earth image below. Cool study site!)

Screen Shot 2015-06-29 at 11.47.54 AM

Last day of fieldwork in England: A working quarry and another great unconformity

June 26th, 2015

1 Doulting quarry sawBRISTOL, ENGLAND (June 26, 2015) — Tim Palmer has a professional interest in building stones, and a passion for sorting out their characteristics and historical uses. He thus has many contacts in the stone industry, from architects to quarry managers. This morning we visited the Doulting Stone Quarry on the outskirts of Doulting near Shepton Mallet in Somerset. Here a distinctive facies of the Jurassic Inferior Oolite is excavated for a variety of purposes. The rock has a lovely color, is relatively easy to work, and is durable. Above is a quarry saw that cuts out huge blocks from the natural exposure.

2 Thalassinoides layer DoultingSuch sawing produces great cross-sections for geologists to examine. We were particularly interested in that light-colored unit above with the irregular top and dark sediment-filled holes. The holes are part of a network of Thalassinoides burrows (tunnels made by Jurassic crustaceans) and reduce the value of the rock as a building stone. There is thus lots of it laying around the quarry yard for study.

3 Pinnid likely Trichites cross section DoultingOne impressive fossil exposed by the sawing is this pinnid bivalve, probably Trichites.

4 Burrow fill sediments DoultingThe Thalassinoides burrows are filled with a poorly-cemented sediment. It is full of little fossils, so we collected a bag of it for microscopic examination. It may give us clues as to what communities lived on the surface of this burrowed unit when it was part of the Jurassic seafloor.

5 shaping saw DoultingWe had a tour of the quarry shops, which included seeing these giant rock saws in action. Many of the saws are controlled by computers, so elaborate cuts can be made.

6 Medieval stone breaking marksThis rock has been quarried since Roman times, so there is over 2000 years of stone working here. The quarry owner set aside this rock face which shows chisel marks made in Medieval times. Wooden wedges were jammed into chiseled channels and then pulled over days to eventually crack the stone free.

7 Tedbury Camp wavecut surface along strikeAfter the quarry visit, Tim Palmer and I tromped through the woods and eventually found (with the help of several locals) an exposure known as Tedbury Camp. It is another Jurassic-on-Carboniferous unconformity like we saw at Ogmore-By-Sea earlier in the week. A century ago quarry workers cleared off this surface of Carboniferous limestone. It is a wave-cut platform on which Jurassic sediments (the Inferior Oolite) were deposited. The surface has many geological delights, including faults, drag folds, differentially-weathered cherts and carbonates, and Jurassic borings and encrusters. Beautiful.

8 wavecut surface foldingIn this view of the surface you may be able to see the odd folding of the dark chert layers in the right middle of the image. These seem to be drag folds along a fault. They clearly predate the Jurassic erosion of the limestone surface. The overlying Jurassic can be seen in the small outcrop on the left near Tim.

9 section view of wavecut surfaceIn this cross-section of the erosional surface you can clearly see we’re working with an angular unconformity.

10 filled borings wavecutTrypanites borings are abundant across this surface, most filled with lighter Jurassic sediment. There are other borings here too that deviate from the straight, cylindrical nature of Trypanites.

11 curved borings wavecutI don’t know yet how to classify these curved borings. They resemble Palaeosabella.

12 Encrusting bivalve wavecutHere is a Jurassic bivalve attached to the Carboniferous limestone at the unconformity. Most of the encrusters have been eroded away.

13 Tim on wavecut platformThere are many possibilities for further study of the Tedbury Camp unconformity. This was a productive site for our last field visit in England this year. Thank you very much to Tim Palmer, seated above, for his expertise, great companionship, and generosity with his time. It was a reminder of how much fun we had together in the field twenty years ago.

My month of geology in the United Kingdom has now come to an end. My next two days will be devoted to packing up and making the long train and then plane flights home. What a wonderful time I had, as did my students on the earlier part of the trip, Mae Kemsley and Meredith Mann. Thank you again to Paul Taylor for his work with us in Scarborough. I am very fortunate with my fine British friends.

For the record, the important locality coordinates from this trip —

GPS 089: Millepore Bed blocks N54.33877°, W00.42339°

GPS 090: Spindle Thorn Member, Hundale Point N54.16167°, W00.23326°

GPS 091: Robin Hood’s Bay N54.41782°, W00.52501°

GPS 092: Northern limit of Speeton Clay N54.16654°, W00.24567°

GPS 093: Northern limit of Red Chalk N54.15887°, W00.22261°

GPS 094: South section Filey Brigg N54.21674°, W00.26922°

GPS 095: North section Filey Brigg N54.21823°, W00.26904°

GPS 096: Filey Brigg N54.21560°, W00.25842°

GPS 097: D6 of Speeton Clay N54.16635°, W00.24520°

GPS 098: C Beds of Speeton Clay N54.16518°, W00.24226°

GPS 099: Lower B Beds of Speeton Clay N54.16167°, W0023326°

GPS 100: Possible A Beds of Speeton Clay N54.16129°, W00.23207°

GPS 101: A/B Beds of Speeton Clay N54.16035°, W00.22910°

GPS 102: C7E layer of Speeton Clay N54.16447°, W00.24043°

GPS 103: Lavernock Point N51.40589°, W03.16947°

GPS 104: Triassic deposits, Ogmore-By-Sea N51.46543°, W03.64094°

GPS 105: Sutton Stone Unconformity N51.45480°, W03.62609°

GPS 106: Sample of lowermost Sutton Stone N51.45455°, W03.62545°

GPS 107: Nash Point N51.40311°, W03.56212°

GPS 108; Devil’s Chimney N51.86402°, W02.07905°

GPS 109: Fiddler’s Elbow N51.82584°, W02.16541°

GPS 110: Doulting Stone Quarry N51.18993°, W02.50245°

GPS 111: Tedbury Camp unconformity N51.23912°, W02.36515°


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