Encrinus liliiformis – a crinoid from the Triassic that made a career for itself: Germany’s fossil of the year, 2019

Jens Lehmann (Germany) Despite their common name ‘sea lilies’, crinoids are animals but not plants, although they look like a flower (Fig. 1). They are related to the sea urchins, sea cucumbers and starfish, groups that are unified as echinoderms (see, for example, Broadhead and Waters, 1980). Crinoids consist of a “root”, a stem built of many disc-shaped elements (columnals) and a crown. Fig. 1. A crown of the famous crinoid, Encrinus liliiformis, from a Muschelkalk quarry in Northern Germany. The fossil shows a slightly opened crown, with a number of arms besides each other. The name “sea lily rock” is often associated with the basal plates of fossilised crowns that resemble a lily flower and were collected as “Lilienstein” (“lily rock”) by gentlemen collectors in Central Europe, particularly in the nineteenth century (Fig. 2). In fact, crinoids were encountered for many hundred years and thus were already known by the famous Swiss and German scientists (respectively), Conrad Gessner and Georgius Agricola, in the sixteenth century. However, these early geoscientists only found the fossils, since living crinoids can only be found in the deep sea and were not known by the scientific community before the eighteenth century. This is the reason why the isolated stem elements called columnals occur in millions of specimens in the German Muschelkalk (Middle Triassic) were mystically called “Boniface pennies” or “Witch money”, before they were recognised as parts of crinoids. Fig. 2: Even details of Germany’s “Fossil of the Year 2019” are beautiful, like these … Read More

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Urban geology: Productid brachiopods in Amsterdam and Utrecht

Stephen K Donovan (The Netherlands) and David AT Harper (UK) The most obvious manifestations of geological materials in the urban environment are building and facing stones, and similar rocks used in street furniture, such as kerbstones. As a Londoner, SKD was impressed as a boy by the massive kerbstones that he saw in the City and locally where he lived. It was only as his knowledge of geology grew that he discovered such stones to be truly exotic, being largely crystalline rocks (mostly granites in the broad sense) and probably derived from the southwest or the north of the British Isles. A field guide to the kerbstones of London would have accelerated his education in geology at that time. More satisfactorily to palaeontologists, such as the authors of this article, are building stones that are fossiliferous. We have particular interests in the palaeontology of Palaeozoic limestones. These are common building stones and street furniture in many cities in the Netherlands (and elsewhere). These rocks are all imported (Van Ruiten and Donovan, 2018; Dr Bernard Mottequin, email to DATH, 9 May 2018) and are mainly Mississippian, although there are some limestones of Devonian age here and there (Van Roekel, 2007; Reumer, 2016). However, the Mississippian limestones are the more widespread and contain abundant fossils, from the well-known, such as bryozoans (Donovan and Wyse Jackson, 2018), brachiopods, crinoids, and rugose and tabulate corals (Van Ruiten and Donovan, 2018) to the more exotic, such as rostroconch molluscs (Donovan and Madern, 2016). This article … Read More

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Fulletby brickyard: A classic locality in the Upper Jurassic Kimmeridge Clay of Lincolnshire

John P Green (UK) The Upper Jurassic Kimmeridge Clay Formation in Lincolnshire crops out along the western edge of the Lincolnshire Wolds scarp (Swinnerton and Kent, 1981) and many years ago was formerly exposed in many small workings that exploited the Lower and Upper Kimmeridge Clay Formation for brickmaking. The once famous brick pits at Market Rasen (TF120888) and at Stickney near Boston (TF342570), both richly fossiliferous and the source of many historic museum specimens (in particular, ammonites and marine reptiles) have long since closed and the sections are no longer accessible. Fig. 1. Saurian vertebra (crocodilian or possible plesiosaur), discovered on the reverse of a Pectinatites ammonite. Nevertheless, I have located another former, now largely overgrown brickyard, near the village of Fulletby (TF298734), situated just under five kilometres north of Horncastle. Whilst largely overgrown, small exposures remain of the Upper Jurassic Kimmeridge Clay Formation. The Palaeontographical Society lists the locality of Fulletby brickyard in its 1954 publication, Directory of British Fossiliferous Localities. It identifies the exposures present as belonging to the ammonite zone of Pectinatites wheatleyensis, and it was indeed thanks to this publication that I was able to discover this locality. The locality is also briefly discussed in Swinnerton and Kent (1981). The exposures that remain are intermittent and scattered, but shallow excavations made by me have revealed a sequence of richly fossiliferous mudrocks, which has allowed a rare opportunity to inspect and collect specimens from this rarely exposed horizon at this little known geological locality in Lincolnshire. … Read More

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Urban geology: Gabions in the Dutch townscape

Stephen K Donovan (The Netherlands) Gabions are tools of the engineering geologist, facing elements that are used to stabilize over-steep slopes, such as sea cliffs or railway/roadway cuttings; they also have military applications. The word is derived from the French, gabion, and Italian, gabbione, and originally referred to “A wicker basket, of cylindrical form, usually open at both ends, to be filled with earth, for use in fortification and engineering” (Little et al., 1983, p. 823). A modern gabion used in engineering geology is a cage, box or cylinder, commonly infilled by rocks or concrete, and sometimes sand or soil (https://en.wikipedia.org/wiki/Gabion). Fig. 1. A gabion wall, lacking subtlety, outside the restaurant, ‘De Blausse Engel’, at Amsterdam Zuid railway station. A: General view of castellated wall, separating restaurant patrons (chairs and tables to left) from passers-by. B: Detail of one cobble in the gabion, showing a vein (sphalerite?). Essentially, gabions provide a stable retaining wall that is semi-permanent. That is, they can be more easily removed, modified or replaced than a permanent structure made in concrete, brick or steel. Although they may be aesthetically unpleasing, gabions provide stability in situations where serious erosion problems may exist, which cannot be controlled by alternatives such as re-vegetation (Freeman and Fischenich, 2000). This is a simplification and studies such as that of Druse (2015) explain something of the complexities. So, in the low-lying Netherlands, what uses might be and are found for gabions? It is reasonable to suggest that they might be used in … Read More

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Urban geology: A rostroconch in Hoofddorp

Stephen K Donovan (The Netherlands) Part of my job is to provide service teaching for the University of Leiden. The university lacks a geology department, but my colleagues and I provide tuition in stratigraphy and palaeontology for life science students at the undergraduate and masters degree level. One of my favourite practical classes is a building stones tour of a part of Leiden that is rich in Mississippian (Lower Carboniferous) limestones, which are packed with fossils. These have been used for facing stones, external stairs and paving slabs. Many have been in place for some hundreds of years and many have been etched by slow solution by rainwater as a result. Common fossils include crinoid columnals, tabulate and rugose corals, brachiopods, and molluscs (Donovan, 2016; van Ruiten and Donovan, in review). These are most commonly seen in two dimensions and random sections, a different view of life to what the life scientists are usually accustomed. One group of fossils in these rocks were a mystery until recently, but we now know they are sections through rostroconchs (Donovan and Madern, 2016, p. 349), an extinct group of Palaeozoic molluscs. Rostroconchs were formerly considered to be an ancient group of bivalves and they are certainly bivalve-like in appearance, but lack an articulation of interlocking teeth and a ligament. That is, the shell is a univalve, a one-piece structure. I had only seen the sections of rostroconchs in building stones in Leiden. It was therefore gratifying, shortly after publication of these fossils, to … Read More

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Fossil folklore: Some myths, monsters, swallows and butterflies

Paul D Taylor (UK) Myths are traditional stories embodying ancient yet false ideas. At the root of many myths lie unusual events, for example, extreme floods, or mysterious objects such as fossils. Numerous myths about different kinds of fossils can be found in the folklore of many countries around the world. Indeed, some ‘monsters’ or mythical creatures of legend – such as the Cyclops, griffins and dragons – may have their roots in findings of fossil bones. Angels’ Money and Slaves’ Lentils The Greek traveller and writer known as Strabo the Geographer (c. 63BC–21AD) visited the pyramids of Gizeh in Egypt, which were then some 2,500 years old (Fig. 1). Fig. 1. The pyramids of Gizeh, constructed of Eocene nummulitic limestone. The pyramids are constructed of Middle Eocene nummulitic limestone. Nummulites are a type of foraminifera. These single-celled protists lived on the seabed and secreted disc-like chambered shells up to 4cm in diameter (Fig. 2), the large size for animals having only one cell reflecting the presence of symbiotic algae in their tissues. Fig. 2. Eocene nummulites from Gizeh, Egypt. The block on the left contains both large and small specimens, ‘Angels’ Money’ and ‘Slaves’ Lentils, respectively. On the right are three specimens of ‘Angels’ Money’, weathered out of the limestone matrix. Fossil nummulites drop out of the limestone at Gizeh after weathering. Picking up examples of these fossils, Strabo was informed that they were the petrified remains of the food belonging to the workers who built the pyramids. Strabo … Read More

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Invertebrate fossils from the Lower Muschelkalk (Triassic, Anisian) of Winterswijk, The Netherlands

Henk Oosterink (The Netherlands) During the Muschelkalk part of the Ansian (240mya), the Central European area (Germany, Poland, Denmark, The Netherlands and north-eastern France) was covered by a shallow sea, referred to as the Muschelkalk Sea. While there were frequent regressions and transgressions (leading to both marine and terrestrial fossil being present in these regions), it is from this sea that the limestones from this quarry were deposited and in which most of the fossilised animals discussed in this article lived. The quarry in the Muschelkalk at Winterswijk, in the east of the Netherlands (Fig. 1), is especially well known for the skeletons, bones, footprints and tracks of Middle Triassic reptiles. I wrote about these in Issues 15 and 20 of Deposits. However, fossils of invertebrates, such as molluscs, brachiopods and arthropods can also be found. Included in the molluscs are bivalves, cephalopods and gastropods, and from the brachiopods, the Inarticulata are present. From the arthropods, there are Malacostraca, Merostomata and insects. Fig. 1. Lower Muschelkalk quarry near Winterswijk (Eastern Netherlands). Mollusca Bivalves Some strata contain a large number of moulds of bivalves. These are situated quite high in the profile and, if you find this level, it is important to split the rock along an irregular dark-grey line (Fig. 2). If you do this, you will find the moulds of the convex upper side of the separated shells on one slab, with the negative impression visible on the other. This makes clear that these are valves swept together by … Read More

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Other mass extinctions

Neal Monks (UK) The extinctions at the Cretaceous-Tertiary (K/T) boundary make up what is probably the most famous geological event in popular culture. This is the point when the great reptiles that characterise the Mesozoic went extinct. Alongside the dinosaurs, the giant marine reptiles died out too, as did the pterosaurs, and a whole host of marine invertebrates, including the ammonites and belemnites. What happened? Some geologists argue the climate changed over a period of a million years or more, thanks to the massive volcanism that created the Deccan Traps in India. Others maintain that the K/T extinctions happened suddenly, pointing to evidence of a collision between the Earth and an asteroid. Perhaps there wasn’t a single cause, but rather a variety of factors: volcanism, climate change, asteroid impact, underlying changes in flora and fauna, and perhaps even variation in the output of the Sun and resulting weather patterns. That life on Earth can be wiped out this way is the stuff of disaster movies as much as TV documentaries. However, what comes as a surprise to many people is that there wasn’t just one mass extinction at the K/T boundary, but a whole series of them that can be observed throughout the fossil record. One of them, the Permo-Triassic extinctions, appear to have been even more catastrophic than the K/T extinctions, and at least three other extinction events are comparable in scale. In between these five big extinctions were lots of smaller extinctions that aren’t well studied, but had … Read More

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Giant trilobites and biotite nodules in Portugal

Peter Perkins (UK) The generally accepted reason for the fame of Arouca is Princess Mafalda, born 1195, who was responsible for the convent becoming Cistercian. Here is an interesting story – she was beatified in 1793. However, I won’t go into that now, but it is well worth investigating. For this article, there are other reasons for its fame, at least among geologists. Arouca is 38km to the south east of Oporto, in northern Portugal, and gives its name to one of two geoparks in Portugal. In Arouca Geopark (Fig. 1), which has an area of 330km2 (just a little smaller than the Isle of Wight), there are two quite remarkable geological features, one palaeontological and the other concerning igneous petrology. Fig. 1. Map of Arouca Geopark. A geopark is an area of significant size that has a particular geological heritage, with a certain number of sites of special importance – scientific quality, rarity, aesthetic appeal and educational value. It must also have a sustainable strategy for development to be accepted as a member of the worldwide network of geoparks. There are 42 in Europe, in 16 countries. The other Portuguese Geopark is Naturtejo, through which the River Tagus flows. There are nine geoparks in the British Isles, for example, NW Highlands (Scotland), Copper Coast (Ireland), Fforest Fawr (Wales) and the English Riviera. The website, http://www.europeangeoparks.org, gives website addresses for all. The geology of Portugal is very complex. There are no strata younger than Triassic, except for Holocene deposits in … Read More

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Mollusc diversity for palaeontologists

Dr Neale Monks (UK) While arthropods and roundworms exceed the phylum Mollusca in terms of species, molluscs hold their own when it comes to anatomical diversity. There may be well over a million species of arthropod, but crabs, spiders and bees are all obviously related, sharing the same multi-limbed body plan organised around a jointed exoskeleton. Molluscs are very different. Clams, snails and squid are all molluscs, but their anatomy, ecology and behaviour couldn’t be more different. What molluscs have in common Although incredibly diverse, molluscs do have features in common. These include: A fleshy foot used for locomotion.A visceral mass containing the internal organs.A mantle that secretes the shell.A toothy tongue, known as a radula, for scraping food into smaller pieces.A shell made from calcium carbonate.Not all molluscs have all of these features, but they each have at least some of them. So, while an octopus doesn’t have a shell, it does have a mantle and a radula, as well as a foot divided up into the eight arms that give it its name. From the perspective of the palaeontologist, the key thing about molluscs is that most have (or had) shells. These fossilise more readily than soft tissues or even bones, and that means that molluscs have a remarkably rich fossil record. Origins The earliest fossil molluscs are known from the very base of the Cambrian, the Tommotian, about 530mya. This period of time was marked by the appearance of several major animal groups alongside molluscs, including arthropods, … Read More

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