Category: Fieldwork

Ichnology of the Ediacaran–Cambrian Chapel Island Formation of Newfoundland, Canada

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Dr. Romain Gougeon, Dr. Gabriela Mángano, Dr. Luis Buatois, Dr. Guy Narbonne, Dr. Brittany Laing, and Dr. Maximiliano Paz have just published their research on bioturbation at the onset of the Cambrian Explosion within the monograph series Fossils and Strata. This is the culmination of 4 field seasons that took place from 2016 to 2021 at the Cambrian-type section in Newfoundland. The monograph consists of a comprehensive ichnotaxonomic review that is essential to understanding the Cambrian explosion from a trace-fossil perspective.

Romain Gougeon and colleagues conducting fieldwork in Newfoundland, Canada. See Fossils and Strata for open access monograph.

The Chapel Island Formation is a 1000+ m-thick, mainly siliciclastic succession that is well-exposed in coastal cliffs of Burin Peninsula, southeastern Newfoundland, eastern Canada. This unit contains an outstanding record of the transition from the Ediacaran (635–538 Ma) to the Cambrian (538–487 Ma). Fossils from the Chapel Island Formation include an incredible diversity of trace fossils, with some intervals rich in small shelly fossils. The monograph integrates sedimentologic and ichnologic information for the whole formation, reinforces the status of the current Cambrian Global Stratotype Section and Point for the Cambrian System, and advocates for the need for more comprehensive and multi-disciplinary approaches and studies to fully decipher the scale, tempo, and loci of the early evolution of animal life on Earth.

Congratulations to Romain and the team on this incredible achievement! You can check out Romans’ ResearchGate profile here, where you can read other studies he’s authored on the Chapel Island Formation throughout the years. These include the origin of the shelf sediment mixed layer and the impact of outcrop quality on trace fossil datasets.

Written by Jack Milligan and Romain Gougeon

Walking with Dinosaurs (2025) featuring Ichnoplanet students

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Dinosaur documentaries have been a great way to communicate the science of paleontology and dinosaurs to a wide audience. Recently, Walking with Dinosaurs has returned with a new version since its original inception in 1999. This time, two Ichnoplanet students make an appearance in one of the episodes!

Jack Milligan and Kaitlin Lindblad feature as part of the field crew during the fifth episode of the new series, titled “The Journey North.” The episode centres on a megaherd of the ceratopsian Pachyrhinosaurus lakustai, as they migrate across the forests, floodplains and rivers of paleonorthern northwestern Alberta during the Campanian stage of the late Cretaceous period. On their journey, they face many dangers, such as infighting among their own, fearsome predators such as the tyrannosaur Gorgosaurus, and sudden flash floods.

Pictures from the Pipestone Creek Bonebed during filming of Walking with Dinosaurs. From left to right: an overhead view of a dense area of Pachyrhinosaurus bones, including limb bones, ribs, and skull material; A grid map created by the field crew prior to collecting the bones; a shot of two of the field crew being filmed by the camera crew. Photos by Jack Milligan, 2023

Jack and Kailtin were invited by Dr. Emily Bamforth, curator of the Philip J. Currie Dinosaur Museum in Wembley, Alberta, to partake in filming of the series, where they excavated bones of Pachyrhinosaurus from the famous Pipestone Creek Bonebed, which has produced thousands of bones since the 1970’s. Fossils that were found during the filming were small juvenile bones, a rib with a pathology, and large frill bones. All these bones were mapped and observed using both traditional and modern methods, including a grid square and 3D scanning software, respectively.

A segment of the episode shows Dr. Bamforth going to a tyrannosaur track site to take silicone moulds of the tracks to study their morphology and discuss the possible tracemaker. This site was published in PLOS One, “The dinosaur tracks of Tyrants Aisle: An Upper Cretaceous ichnofauna from Unit 4 of the Wapiti Formation (upper Campanian), Alberta, Canada” by Enriquez et al., 2022.

Walking with Dinosaurs is available now to buy on physical media and on streaming. Check out the official trailer and a behind-the-scenes featurette featuring Jack!

Listen to CBC Saskatoon Morning and CBC Saskatchewan The Morning Edition radio interviews with both Jack and Kaitlin talking about their experience being involved in the production of the show.

Written by Jack Milligan

Grasslands National Park Fieldwork 2024

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Towards the end of the summer, I had the opportunity to continue fieldwork at two multitaxic Edmontosaurus quarries within the Uppermost Cretaceous Frenchman Formation in the East Block of Grasslands National Park in southern Saskatchewan under the supervision of Dr. Emily Bamforth of the Philip J. Currie Dinosaur Museum and Dr. Ryan McKellar of the Royal Saskatchewan Museum. These excavations have been ongoing and have yielded some fantastic fossil specimens and interesting geology.

We collected a limb bone (tibia) from one of our two Edmontosaurus quarries, called the “Leo” quarry. The tibia shows feeding traces as evidenced by well-defined tooth marks. During the excavation of the tibia, a shed tooth from a tyrannosaurid (Tyrannosaurus rex) was collected from the same depositional layer. This association of tooth traces on Edmontosaurus bones and T. rex teeth suggests that Leo was scavenged during subaerial exposure on a floodplain within a meandering fluvial system. Limb bones have a high likelihood of being consumed due to large locomotor muscles being present (a great food source for predators like T. rex), and thus will tend to have more tooth traces on the bone.

On an adjacent butte within the same depositional layer as the “Leo” quarry, there is a point bar deposit containing a second active quarry named the “Clifford“ quarry. While the Edmontosaurus in this quarry has yet to produce elements with tooth marks, teeth from T. rex and the crocodyliform Borealosuchus have shown up this past season. Adding to the mystery of this quarry, several articulated turtle skeletons have been collected from this deposit, showing no evidence of being scavenged.

Tooth marks have been a widely debated aspect of vertebrate ichnology. Recently, the category-modifier (CM) system was proposed by Wyenberg-Henzler et al., 2024, as a method to identify different morphologies of tooth marks and their associated behaviours. While not strictly defined within a traditional ichnological framework, it is the most comprehensive overview of tooth marks on bones in the literature to date. Based on the CM system, the tooth marks left on the Edmontosaurus tibia appear to be internally chattered, referring to the crescentic depression on the inside of the tooth mark. Shed carnivore teeth from both quarries suggest that the dominant predators within this ecosystem were crocodyliforms and tyrannosaurs.

Further excavation of the quarries is required, and research into the taphonomy of these two Edmontosaurus quarries is ongoing, but there are sure to be some exciting discoveries to be made in future field seasons!

Written by Jack Milligan

Eastend Summer Fieldwork 2024

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Throughout this past summer, I had the opportunity to volunteer with the Saskatchewan Geologic Survey under Dr. Meagan Gilbert in my hometown of Eastend, Saskatchewan. This project aimed to characterize the stratigraphy and depositional environments of the Upper Cretaceous and lower Paleogene of southwest Saskatchewan.

Skolithos isp. in a crossbedded sandstone fluvial channel deposit in the buff facies of the Upper Ravenscrag Formation in southwestern Saskatchewan. Photo provided by Mollie Black

We went to many different geologic outcrops around the town of Eastend. A typical day consisted of taking measurements and samples (so many samples) across the section. A section was first chosen based on the extent of exposed bedrock and then measured from the lowermost exposed bedrock to the top. It wasn’t all just rocks, though! We also found many neat trace fossils and plant fossils, including many just above the KPg boundary.

A huge thank you to all landowners who allowed access to their land.

Written by Mollie Black and Dr. Meagan Gilbert

Jurassic paleosurfaces with fecal mounds reveal the last supper of arenicolid worms

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Recently, new research by Gabriela Mángano, Luis Buatois, and coauthors from Stoney Brook University and the MUJA near Colunga, Asturias, Spain, on fecal mounds produced by arenicolid worms from the Upper Jurassic Lastres Formation in Asturias, Spain, has been featured in local news in Asturias. Students who have recently taken the Asturias geology field course offered through the University of Saskatchewan had the opportunity to see these trace fossils in the collections/galleries at the Museo del Jurásico de Asturias (MUJA).

Figure from Mángano et al., 2024 showing the stratigraphy and detailed sedimentologic characteristics of the lowermost Upper Jurassic interval of the Lastres Formation at Arroyo Solero containing one of the surfaces with fecal cast mounds, including a close-up picture of the deposits showing the bedding surface that contains fecal cast mounds in cross-section.

The fecal mounds were given the name Cumulusichnus asturiensis. They are made up of an accumulation of thin sandstone cords roughly 1 to 2.3 mm thick and are preserved on a paleosurface comprised of rippled sandstone formed by wave action. The traces are preferentially located within the depressions located between the crests of the ripples. In the modern, the worms that generate this type of structure are known as Arenicola marina, a benthic polychaete from the family Arenicolidae (also called lugworms) that can be found in estuaries, deltas, tidal flats, and shallow marine settings of Europe. North America and New Zealand. The worm lives upside down inside the sediment inside an L- or J-shaped tube (domichnia) and feeds on bacteria and various microorganisms that live within the substrate. The worm swallows sand, takes in nutrients, and expels the waste, forming small sandy fecal piles on the surface that resemble squiggles or spaghetti.

Figure from Mángano et al., 2024, showing examples of arenicolid fecal mounds from Playa España, Upper Jurassic Lastres Formation of Asturias, Spain. Scale bars are 2 cm long.

You can read the paper in the journal Nature here. You can watch a brief news clip (in Spanish) here (skip to 11 min 40 sec). You can also read an article and watch another video highlighting the discovery here. Once again, congratulations to Gabriela, Luis, and the other researchers involved with this project!

Written by Jack Milligan