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fossils geology north america palaeontology

The disparids: Weird and weedy crinoids of the Palaeozoic

Stephen K Donovan (Netherlands) and David N Lewis (UK) Palaeozoic crinoids are uniformly beautiful and come in many shapes and sizes, but almost all fall into one of three principal groups. The camerates are the largest and most robust, commonly incorporating the lower part of the arms into an enlarged cup with a plated roof (tegmen), producing a structure that is commonly reminiscent of a golf ball. The cup may be monocyclic (one circlet of basal plates supporting the radials; see Glossary (below) for explanation of specialist terms) or dicyclic (two basal circlets, that is, infrabasals and basals, supporting the radials). The arms of camerate crinoids bear multiple, fine branchlets called pinnules that must have formed an efficient ‘net’ for feeding on plankton. The second major group, the cladids (plus the closely related flexibles) are dicyclic, lack an armoured tegmen and, except for some advanced (Upper Palaeozoic) forms, lack pinnules. The flexibles may also show a camerate-like feature with small plates separating the arms. And then there are the disparids. The disparids were the ‘weeds’ of the Palaeozoic crinoids; generally smaller and less impressive than other crinoids, but including some unusual, even bizarre forms. Herein, we introduce the disparids of the British Palaeozoic, examining their form and function, and where to collect them. The disparid cup was commonly small, always monocyclic and lacked an armoured tegmen, but had a prominent anal sac or tube in some groups. The arms were usually slender, lacked pinnules and were branched or unbranched, and … Read More

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Locations Nova Scotia (Part 3): Wasson’s Bluff – a locality near Parrsboro

George Burden (Canada) The Wasson’s Bluff fossil site, near Parrsboro, is the most geologically recent, yet perhaps the most fascinating of the locations of interest to palaeontologists in Nova Scotia. Located on the Bay of Fundy’s Minas Basin, fossil buffs can view what are perhaps the smallest dinosaur footprints ever found. In 1984, amateur palaeontologist, Eldon George, discovered the track ways, most likely made by a juvenile Coelophysis sp., which lived 200 million years ago, at the Triassic-Jurassic boundary. Two years later, Neil Shubin of Harvard University and Dr Paul Olsen of Columbia University, discovered at this site over 100,000 tiny bones of ancient crocodiles, various sized dinosaurs, lizards, fishes and sharks. Their efforts were funded by the National Geographic Society, which recognised that this was North America’s largest find ever of fossils from this era. Fig. 1. A walking tour at Wasson Bluff near Parrsboro where the remains of a dinosaur are being uncovered by a group of geologists from the Fundy Geological Centre. Vast mudflats in this region’s ancient terrain record the tracks of the creatures from this time. Covered by sand washed down from the Cobequid Highlands, an elevated, quartz bearing area, to the north of Parrsboro, natural casts of the footprints were formed. However, today, this site provides an ideal location to view more than just trace fossils from the crucial Triassic-Jurassic transition period, during which a mass extinction occurred. It is notable in that both the remains of bones and foot prints (which are so … Read More

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Locations in Nova Scotia (Part 2): Blue Beach – a locality in the Annapolis Valley

George Burden (Canada) In this second article on fossil locations in Nova Scotia in Canada, I will discuss the fascinating site of Blue Beach. This is perhaps the least known and most under-appreciated of the three major fossil cliffs in Nova Scotia. Most residents of the province (including me, until a few months ago) are unaware of the site. This is a pity, for it is the most accessible of the three sites in the Halifax Regional Municipality, which is the major population centre of Nova Scotia. Blue Beach is located just outside the town of Hantsport in the Annapolis Valley, just off Highway 101. Chris Mansky, a knowledgeable amateur palaeontologist, and Sonja Wood own and run a private interpretation centre and museum. Chris takes visitors on a tour of the museum and down to the beach, pointing out interesting fossils and sharing his, not inconsiderable, knowledge of this important deposit, which dates from Romer’s Gap in the Early Carboniferous Period (360  to 340 million years ago). Romer’s Gap, named after palaeontologist Dr. Alfred Romer, was a period from about 360 to 340 million year ago from which fossils are rarely found. It is not known for sure why this is the case, but this was also a crucial time for tetrapod development. Along with the Kirkton Quarry in Bathgate, Scotland, Blue Beach is one of the few sites Gap fossils are accessible. As Chris says: One of the first things a visitor will notice about Blue Beach is that … Read More

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Locations in Nova Scotia (Part 1): Joggins – a Carboniferous fossil forest

George Burden (Canada) There are three fossil sites of major interest to both professional and amateur palaeontologists in Canada’s east coast province of Nova Scotia. These are the Upper Carboniferous Horton’s Bluff/Blue Beach site, the Parrsboro fossil site at Wasson’s Bluff (which just post-dates a mass extinction event at the Triassic-Jurassic boundary) and the Lower Carboniferous site of Joggins. It is this last site that I will concentrate on. Fig. 1. Map of Canada and the Joggins site. Perhaps, the most famous of these three is the Joggins site, which has just received designation as a UNESCO World Heritage Site. Its fossil cliffs, which are the remains of a 300 million-year-old forest, are washed twice daily by the immense Bay of Fundy tides – at up to 15m, the highest in the world. New fossils are constantly unmasked by tidal action, and the trunks of huge Lycopod trees can be seen studding the cliff face. Fig. 2. Bark of Lepidodendron sp. (Lycopod). Joggins became world-famous in 1851, when Sir Charles Lyell and Sir William Dawson discovered the remains of what is, arguably, the World’s oldest reptile, Hylonomus lyelli, tucked inside the trunk of a fossil tree. Dawson guessed correctly that small creatures would become trapped in hollow tree trunks and, indeed, multiple specimens are often found in these locales. Later, Charles Darwin would mention the site in his book, The Origin of the Species, prompting some to call Joggins the “Coal Age Galapagos.” A walk on the beach at Joggins … Read More

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Ice, dykes and tectonics: the Plattsburgh story

Deborah Painter (USA) As our small passenger jet began its descent into the Plattsburgh, New York International Airport on a cool November day, I admired Lake Champlain to the east from my window and noticed that the small aircraft, once it touched the very long runway, continued rolling down it for ten whole minutes. When the jet came at long last to the gate area, I noted that the size of the attractive terminal was small – quite out of proportion for that enormous runway. On returning to the terminal and dropping off my rental car two days later, following completion of an environmental compliance project, I noticed that the young lady who checked my bags and took my ticket at the gate was the same person who loaded the plane’s baggage compartment. Why should such a tiny airport with such a tiny staff and only a few arrivals and departures daily need such a long runway and taxiway? Later, I learned that this had been an Air Force base in the past and the runway had been intended to serve as an alternate runway for NASA’s Space Shuttle in case of an aborted mission. Less than three years later, I had the good fortune to have another project in Plattsburgh. This time, I took a passenger train and, since the rail line runs parallel to and very close to Lake Champlain through much of its service through New York north of Albany, I was able to see the lake … Read More

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Stones that illustrate themselves

Deborah Painter (USA) Earlier in the month of September 2022, my friend David and I spent an afternoon with a fellow named Ellery, a long-time member of a rock collecting club we joined a year ago. Ellery allowed me to photograph some of his rock and mineral specimens, including a rough piece of ‘wonderstone’ of approximately 30cm in length and 19cm in width, from southern Utah, USA (Fig. 1). Fig. 1. Shinarump Wonderstone is a variety of chalcedony that features swirls and other decorative patterns. (Credits: Deborah Painter; specimen from the collection of Ellery Borow.) The piece contained what looked like a painting of the flanks of a slot canyon one might see in the very area where it is found (Fig. 2). Fig. 2. A slot canyon in Page, Arizona USA, just 180km to 185km from known sources of Shinarump Wonderstone. It reminds one of the ripples and swirls in the Wonderstone in Fig. 1. (Credits: Brigitte Werner, Pixabay.) On the opposite side of the same specimen was a fish’s head, complete with an ‘eye’ (Fig. 3). Fig. 3. This ‘fish head’, complete with a fishy ‘eye’ is the image that greets you when you turn over the Shinarump Wonderstone specimen in Fig. 1. (Credits: Deborah Painter; specimen from the collection of Ellery Borow.) None of the images were artificial or cut in a particular way to bring out these ‘images’. I was instantly reminded of the pietra paesina stones of the Florence area of Italy. The latter have … Read More

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It doesn’t always have to be dinosaurs – a short review of rauisuchian archosaurs

Stephan Lautenschlager (Germany) and Dr Julia Brenda Desojo (Argentina) Fig. 1. Reconstruction of Batrachotomus kupferzellensis. (Museum of Natural History, Stuttgart, Germany.) Among the multitude of fossil animals, dinosaurs have always been the most popular and fascinating. Loved by six-year-olds, Hollywood directors, toy-designers and scientists alike, they not only dominated most of the Mesozoic Era, but still dominate our understanding of palaeontology. However, only a few people are aware that, before the dinosaurs started their 150-million-year-long global dominion, there was an equally successful and remarkable group of fossil reptiles – the ‘rauisuchians’ (Fig. 2). In this article, we will try to shed some light on these enigmatic and commonly unknown tetrapods, which were as adapt and predominant in their time – and, to be honest, as cool – as the dinosaurs. Fig. 2. Occurrence and evolution of the major archosaur groups. A history of rauisuchian research The first rauisuchian fossil was found in 1861 by the German naturalist Hermann von Meyer. It consisted of a single maxilla of Teratosaurus suevicus and was identified as an early dinosaur. The same happened to the next to be found, Poposaurus gracilis, after its discovery in Wyoming in 1915. This specimen was subsequently described as a theropod dinosaur, a primitive stegosaurid and also an ornithopod. Only when the German palaeontologist, Friedrich von Huene, collected numerous Triassic fossils from the Santa Maria Formation of Brazil in 1928, did things begin to change. His detailed studies of the material revealed that most of it did not belong … Read More

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Pennsylvania’s forests looked different in the Carboniferous and Early Permian

Deborah Painter (USA) A singer named Perry Como caused this article to be written. Perhaps it would be more correct to credit his statue. My friend Richard and I took a road trip in June 2018 to a conference in Cranberry Township, Pennsylvania, USA for a three-day weekend. On Sunday afternoon, we were facing a seven hour drive south back to our homes. Fortunately, the weather was sunny and mild, a good way to conclude a trip that had been plagued with thunderstorms earlier. We were both tired, but Richard allowed me to stop off Interstate 79 to Canonsburg, Pennsylvania to see a statue in honour of Perry Como, an American celebrity of the mid-twentieth century. I admit I didn’t know why I wanted to see it, since I am not especially a fan of the recording artist and television star, and neither is Richard. However, I was curious about it because I had read that it continuously plays music. I also thought Canonsburg (Fig. 1), a quick turn off the Interstate highway in Washington County, might be a good stopping place for us to find a restaurant before proceeding on the long journey back. Fig. 1. Canonsburg is an older suburb of Pittsburgh, Pennsylvania USA in Washington County. (Credits: Deborah Painter.) Perry Como’s mellow style of jazz and big band made him a recipient of a Kennedy Center Award for outstanding achievement in the performing arts. His style and choice of music was not unlike those of the even … Read More

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In the footsteps of T-rex and other prehistoric giants: my trip to Hell Creek, the Green River Formation and the Niobrara Chalk

George Corneille (UK) It was Christmas 2005 and I received a phone call from the USA from my good friend, Terry Boudreaux. He asked if I wanted to join him and his boys, Christopher and Evan, on a trip to hunt dinosaurs in Hell Creek in South Dakota, fossil fish in Kemmerer, Wyoming and Cretaceous marine life in the chalk formations of Gove County, Kansas. Well, he didn’t have to ask twice and, in June of 2007, I arrived in Chicago to begin my 4,500 mile road trip to some of the most famous fossil sites in the world. On the morning of Sunday, 25 June 2006, we left Chicago to begin our fossil adventure. I was full of anticipation, dreaming of a finding a mosasaur or maybe a four-inch T-rex tooth (or even just a fossil fly). On the first day, we drove to Sioux Falls, South Dakota, arriving the next day in Rapid City S.D. where I had an opportunity to visit the Black Hills Institute and see their stunning collection of dinosaur fossils. I suppose the most impressive fossil was the complete Triceratops lying in situ, as he has done for the last 65 million years, and the giant skull from a Deinosuchus, the massive prehistoric crocodilian. We continued our journey and, that night, arrived in Buffalo, South Dakota where we would spend the next few days hunting dinosaurs. Fig. 1. Outside the ranch house in Buffalo, S.D.. Back row from left: Terry, Alyson, Ryan, Steve, Christopher … Read More

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Down and dirty at a dig: a dinophile’s dream comes true

By Elena Victory “You really should go on a dig” was the advice of a dear friend during the long, rainy winter of 2005. I was just gearing up to teach my annual, introductory paleontology class at a small college near my home outside Portland, Oregon. “Where?” I asked. “Who specialises in fanatics who read lots of dinosaur books and dream a lot, but has never dug up a real dinosaur?” She smiled and said, “I think Nate Murphy’s program would be good for you”. It unfolded from there. I emailed Nate to find out availability. He emailed back, directly I might add. And so, I found myself outside of Billings, MT en route to my first real dig. It was a beautiful landscape: a few lonely Ponderosa pines stood like silent sentinels over a grassy landscape dotted with spurges, thistles and wormwoods. Through the eyes of a botanist, it didn’t look like dinosaur country to me. That night, after a group of 35 excited diggers had made camp and their introductions, we were given a little history. The next day, we were going to dig our awls and shovels into the “Mighty Morrison”, a huge geological layer cake of shales and mudstones spanning several states and several thousand square miles. The Morrison graveyard also records a story of climate change. Early in the Jurassic period, Apatosaurus roamed on its home range encountering arid seasons part of the year and deluges the rest of the season (poor thing, I thought, … Read More

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A new Park County gem discovery: Tarryall fire agate

By Steven Wade Veatch Exceptional specimens of iridescent fire agate have recently been found in Park County in the USA, close to Tarryall Creek and near the Tarryall Reservoir. Fire agate is a variety of chalcedony (pronounced kal SED’ uh nee), a form of microcrystalline or cryptocrystalline (crystals too small to be seen without high magnification) quartz (SiO2). It contains inclusions of iron oxide (limonite) that produce an iridescent effect or ‘fire’. Chalcedony is generally formed near the surface of the Earth, where temperatures and pressures are low. The Tarryall fire agate has a botryoidal (grape-like) growth form. The agate is also layered: it contains thin layers of plate-like crystals of iron oxide in various planes. When light travels through these thin layers, the planes produce the iridescent colour play of red, gold and green. Fig. 1. Good fire agates are impressive in their rich and dramatic colour play. They form in cavities and cracks in the country rock from low temperature, silica-rich waters, in a way similar to how black opal forms. Lee Magginetti specimen. Photo date June, 2007, © by S. W. Veatch. The fire agate specimens were found as seams in granite near the Tarryall Creek. This  is a tributary of the South Platte River, approximately 25 miles (40km) long, in Park County, central Colorado. It drains a portion of north and central South Park, an intermontane grassland south-west of Denver. Tarryall Creek runs in several forks along the continental divide in the Pike National Forest and … Read More

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That Arizona hot spot might be a volcanic field

Deborah Painter Let’s see, when I say “Arizona hot spots”, what might come to mind for many people are the restaurants, nightclubs and sports events in Phoenix (the US state’s largest city), the Grand Canyon of the Colorado River, attracting visitors from around the world, Tombstone (the infamous “town too tough to die”, where the equally infamous 1881 gunfight at the OK Corral took place), and any portion of the desert in the daytime during August. But how many people think of the many volcanoes in Arizona USA, part of a volcanic field that is likely not finished erupting? Arizona, USA has seven young (Quaternary Period) volcanic fields. The three youngest fields are the San Francisco, Uinkaret and Pinacate volcanic fields. The first two of these young fields are on the Colorado Plateau of northern Arizona; the Pinacate Field is much farther south on the Arizona-Mexico border. The San Francisco Field is the focus of this article. It is situated near Flagstaff and Williams in northern Arizona (Fig. 1). It extends approximately 5,0002km from Williams to the Little Colorado River. There are slightly over 600 cones. The field was active as recently as 932 BP (Before Present), with the eruption that formed Sunset Crater at Sunset Crater Volcano National Monument. Fig. 1. The San Francisco Volcanic Field. (Credits: United States Geological Survey/Wikimedia Commons.) The spectacular San Francisco Peaks within this field are originally a single stratovolcano that experienced deep erosion (Fig. 2). Mount Elden near Flagstaff is a large volcanic … Read More

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Environmental scientists and geology (Part 3): Geology and soil science in the ‘National Environmental Policy Act document’ process in the USA

Deborah Painter (USA) I am an ecologist and general environmental scientist, specialising in transportation, energy and industrial development planning to minimise deleterious environmental impacts. I live in the United States and have also written several articles for this magazine. I appreciate just how important local geology and soil science are … Read More

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Environmental scientists and geology (Part 2): Geology and soil science in the ‘Wetlands and Waters Permitting’ process in the USA

Deborah Painter (USA) I am an ecologist and general environmental scientist specialising in transportation, energy and industrial development planning to minimise deleterious environmental impacts. I live in the United States and have also written several articles for this magazine. One of the things I really appreciate is just how important … Read More

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Environmental scientists and geology (Part 1): The first phase of an environmental geology investigation

Deborah Painter (USA) I am an ecologist and general environmental scientist living in the USA and specialising in transportation, energy and industrial development planning to minimise deleterious environmental impacts. I have also written several articles for this magazine. As such, I appreciate just how much local geology is a vital … Read More