Take me to the rocks

Dr Sebastian Lüning (Germany) I am a geologist by profession. Everyday of my working life, I have worked with rocks, from nine to five, for 19 years, looking for oil and gas in the Sahara. Sometimes this is stressful, sometimes really enjoyable and sometimes simply annoying – just like any other job. However, I’ll tell you a little secret about what I do in my limited spare time to refresh my mind and recharge my batteries for another day. I am so in love with my rocks that I am also a hobby geologist. I just cannot keep away from the rocks. There are plenty of interesting fields open to amateur geologists and palaeontologists to indulge in. Most popular are probably collecting minerals and fossils, including visiting quarries and searching beaches for new specimens. However, my hobby is focused on regional geology. I love to understand the earth history of a particular area, by visiting its outcrops and reading the regional geological descriptions that have been published about it. That is, I like to look behind the scenes of a modern landscape to understand how it was shaped and what lies underneath. I drive and walk through my object of study to understand its dimensions, distances and height. At one moment, I can pay attention to millimetre-sized fossils and, a few minutes later, be enjoying a panorama across kilometre-scale valleys shaped by ice. I am convinced there are many other amateur geologists, who share my passion for an integrated view … Read More

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Caught between two mass extinctions: The rise and fall of Dicroidium

Chris Mays and Stephen McLoughlin (Sweden) In the aftermath of Earth’s greatest biotic crisis 251.9 million years ago – the end-Permian mass extinction – a group of plants arose that would come to dominate the flora of the Southern Hemisphere. Recovery of the vegetation from the end-Permian crisis was slow; but steadily, one group of seed plants, typified by the leaf fossil Dicroidium, began to diversify and fill the dominant canopy-plant niches left vacant by the demise of the Permian glossopterid forests (Fielding et al., 2019). Eventually, Dicroidium re-established a rich peat-forming vegetation across Gondwana through the Late Triassic, dominating the flora between 30°S and the South Pole (Kustatscher et al., 2018). Indeed, few fossil plant assemblages of this age can be found in Gondwana that do not contain this plant. The importance of Dicroidium is not just its role in showing biogeographic and tectonic linkages between southern lands or its value in determining the age of continental strata. Dicroidium and its associated plant groups were so successful that they were major contributors to the development of thick coal seams in the Late Triassic that are now mined to produce electricity. Although Dicroidium is generally envisaged as a plant of cool temperate climates, the very first fossils that might belong to this group are from the Permian-Triassic transition of Jordan, located near the palaeoequator (Blomenkemper et al., 2018). Nevertheless, the distribution of Dicroidium soon shifted to high southern latitudes in the Early Triassic and they overwhelmingly dominated the southern vegetation … 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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Golden Dinosaur from the depths of the London Mine: Mystery of Genevieve

Steven Wade Veatch and Teresa L Stoiber (USA) The legend of “Genevieve”, a fossilised dinosaur not only made of stone — but also of gold — began on 3 July 1932. That was the day WK Jewett, owner of the London Mine near Alma in Colorado, stopped at the Antlers Hotel in Colorado Springs and made the official announcement of its unearthing. The story was picked up by the news services and word of the fantastic find spread through the scientific world like a prairie fire. The golden dinosaur was discovered by William White, 700 feet (213m) underground — deep in the London Mine (WK Jewett, 1932). Curiously, the miners had been using the creature’s nose as a lamp holder, not realising there was a ‘dinosaur’ (if that is what it was) there. White, a hard rock miner, believed at first he was looking at two stumps. In reality, it was a dinosaur lying on its back with its limbs at an angle of 75 degrees. Eager to retrieve it from its rocky tomb, miners blasted it out of rock at the 700-foot level of the London Mine with dynamite. The blast shattered the specimen. Bits and pieces of the dinosaur were hoisted to the surface, where curious crowds gathered to see the prehistoric monster. As the story goes, a geology professor at Colorado College, Robert Landon, travelled to Alma so he could examine Genevieve – an extraordinary record of a former world. The measurements he made revealed that the … Read More

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Pistol shrimps: How to recognise them in the fossil record

Matúš Hyžný (Slovakia), Andreas Kroh (Austria), Alexander Ziegler (Germany) and John WM Jagt (The Netherlands) Alpheid shrimps, colloquially referred to as “pistol shrimps”, exhibit a remarkable anatomical adaptation. These tiny marine crustaceans use their enlarged and highly modified claw to ‘shoot’ at their prey – hence their name. It is astonishing that the snapping claw evolved at least 30 million years ago. How do we know that? Because the fossils tell us. Fig. 1. Habitus (body form) of alpheid snapping shrimps, exemplified by the extant species Alpheus thomasi from the Caribbean Sea. (Photo: Arthur Anker.) The famous snapping claw Alpheid pistol shrimps represent a super-diverse group of benthic marine crustaceans (that is, living on the bottom of the sea, including the sediment surface and some sub-surface layers). There are more than 600 living species, nearly half of which belong to the genus Alpheus. Its representatives possess a snapping claw, a multifunctional tool used for various types of behaviour such as aggression, warning or defence, as well as for hunting prey. Although snapping claws evolved independently several times within various decapod crustaceans, only in pistol shrimps did this organ attain true perfection. Fig. 2. Pistol shrimps ‘shoot’ with an enlarged, modified claw. (Photo: Arthur Anker.) The process of snapping involves a cracking sound reaching up to 210 decibels, one of the loudest produced by any animal. This noise originates from the collapse of a cavitation bubble in front of the claw, which, in addition, is accompanied by a short flash of … Read More

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Crinoids at Hartington

Stephen K Donovan (The Netherlands) Much of the secondary railway route in Derbyshire, from Buxton south to Ashbourne, was closed in the 1950s and 1960s. Today, only the northern section is still in use as a railway, providing a route for major limestone quarry traffic (Roberts and Emerson, 2018). But the remainder of the line, from about 2.25km north of the closed Hurdlow station (Rimmer, 1998, p. 102), all the way to Ashbourne – a distance of about 27.5km – is now open as a cycle path called the Tissington Trail. This is part of the High Peak Trail north of High Peak Junction, which is south of Parsley Hay, and provides excellent access. For a map, see http://www.peakdistrict.gov.uk/__data/assets/pdf_file/0009/90486/hptisstrails.pdf. The interest of this route for the geologist is that most of it is through the Carboniferous limestones (Mississippian) of the Derbyshire plateau. The beauty of the scenery combines with the accessibility of exposures in railway cuttings to provide much of interest to the geologist on foot or bicycle. The northern part of the route, from south of the site of Hurdlow station, through Parsley Hay (with cycle hire and a cafe) to Hartington, is described in a brief field guide by Simpson (1982, pp. 102-107). My interest in these limestones is for their fossil crinoids. These are commonly difficult to see in the massive beds of limestone, which, over many years, have developed a surface patina that conceals internal features such as fossils. As this is a national park, there … Read More

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Brihadeeswarar Temple, India

Khursheed Dinshaw (India) Construction of the Brihadeeswarar Temple (also spelt Brihadisvara or Brihadeshwara), which is in Thanjavur in the state of Tamil Nadu, India, began in 1003 AD by Rajaraja I and was completed in 1010 AD. It is made of blocks of granite that were sourced from around 50km away. Almost 130,000 tonnes of granite were used to build this temple. The popular theory of how the blocks were transported is that they were gradually rolled here with the help of elephants. The design of the temple is meant to represent a cosmic structure called Mahameru, which symbolises energy from the universe, including from living as well as inanimate beings. The temple is dedicated to Lord Shiva in the form of a lingam (that is, a symbol of divine generative energy often in the form of a phallus), which is 3.66m high. The courtyard inside which the temple is built measures 240m by 120m. The Brihadeeswarar Temple, also known as the Big Temple, is an architectural marvel in stone of the Chola dynasty. It is also a UNESCO World Heritage Site. The tower, which is built over the sanctum, has a height of about 66m and has 13 storeys (Fig. 1). Fig. 1. The tower built over the sanctum has a height of 217 feet and has 13 stories. There are eight sikharas (spires), which are also made of stone and weigh about 81 tonnes. There are two circumambulatory passages. The walls of the lower passage are decorated with … Read More

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Fossil spiders in Baltic amber

Anthonie Hellemond (Belgium) Spiders represent the most diverse group of obligate predators (that is, predators that feed solely on other animals) in terrestrial ecosystems today, with almost 48,000 extant species in 118 families described to date. The number increases annually by approximately 500 species as a result of new discoveries and it has been estimated that the true diversity may number around 160,000 extant species. This great diversity is no doubt at least in part due to their geological longevity, with the oldest known fossil spider dating back to the Carboniferous. In addition, spiders appear to have co-radiated along with their insect prey over geological time and they also appear to have been relatively resistant to extinction during the major events that eliminated many other terrestrial animal groups, such as the dinosaurs (Penney and Selden, 2011). Most people seem to presume that spiders do not have a very good fossil record on account of their very small size and their lack of a mineralised, bony skeleton. However, spiders actually have a very good fossil record, with 1,347 fossil species currently recognised. Fossil spiders occur in rocks of various different types, but the vast majority and best-preserved spiders are found as inclusions in amber from various localities dating back to the Cretaceous, although preservation tends to be better in the younger (for example, Miocene and Eocene) ambers. The best known of these deposits is Baltic amber, with more than 650 fossil spider species recognised (Penney et al., 2012), representing close to … Read More

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Duria Antiquior: A nineteenth-century forerunner of palaeoart

Steven Wade Veatch (USA) Fig. 1. Duria Antiquior. A watercolour painted in 1830 by Henry De la Beche, who conjured up a vivid picture of an ancient world. It is now in the National Museum of Wales and another copy can be seen at the Sedgwick Museum in Cambridge. (Image is public domain.) In a breath of inspiration in 1830, English geologist, Henry De la Beche (1796–1855), while exploring new intellectual territories in the emerging fields of palaeontology, painted Duria Antiquior (meaning “a more ancient Dorset”), a representation of a prehistoric Dorset coast. De la Beche’s work was ground breaking – his artwork combined science and art in the first artistic rendering of a paleontological scene, while laying bare the secrets of the past. Before 1830, art depicting the prehistoric world did not exist and these realms were unknown to the public (Porter, n.d.). While it is true that scientists made drawings of fossil animals and exchanged them with each other in private letters, the public had no concept of how prehistoric animals looked. This painting opened people’s imagination to new visions, thoughts and beliefs. De la Beche’s painting also laid the foundation for a new genre that would later be known as palaeoart, an artistic genre that reconstructs prehistoric life according to the fossil record, scientific understanding and artistic imagination. De la Bache’s brushstrokes of prehistoric time included (literally) all the information known at that time about ancient life and soon became the first teaching graphic used in the … Read More

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Concretions in sandstones of the Inner Hebrides, Scotland

Mark Wilkinson (UK) Concretions are a common feature in many sedimentary rocks, yet they seem sometimes to be misunderstood. So, how do concretions form? As well-studied examples, let’s look at the ones found in some of the sandstones of the Scottish Inner Hebrides, notably the islands of Eigg and Skye. The concretions are found in several formations, but perhaps the largest and most spectacular are in the Valtos Sandstone Formation of the Great Estuarine Group. This was originally named the Concretionary Sandstone Series after the prominent metre-scale concretions. It is Bathonian in age (Middle Jurassic) and is interpreted as having been deposited in a coastal environment. The Great Estuarine Group is becoming famous for its abundant dinosaur footprints and much rarer skeletal material. The concretions themselves vary from spherical to elongate volumes of rock and are typically from around 50cm to one metre or more in diameter. They are also often coalesced into groups (Fig. 1). Inside the concretions, the spaces between the sand grains are filled completely with a calcite cement. The concretions are resistant to weathering compared to the host sandstone, which is fairly soft, so stick out from the cliff in a sometimes rather alarming manner as you walk below them. I’ve been visiting the concretions sporadically for around 30 years and some of the ones that I photographed in the cliffs in the 1980s are now lying loose on the beach. None of them have fallen while I’ve been there, touch wood. Fig 1. Concretions on … Read More

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Rudists: A fossil story

Jack Shimon (USA) This article is adapted from a presentation given at the Denver Gem Show, September 17, 2016 by me, Jack Shimon. When I was six and a half years old, my Grandpa took me fossil hunting in central Texas. We went to a Carboniferous Limestone quarry that he had visited earlier and was given permission to enter and collect from. This was one of my first fossil hunting trips and I really enjoyed it. The ancient reef we went to (now a quarry) had huge boulders of limestone and tube-like things in it we later to be found to be rudist bivalves. This article is all about these finds and the efforts we went to, to find out what they were. Fig 1. The author at the quarry. (Photo credit: Mike Hursey.) Fig. 2. This Google satellite image shows the reef we collected from. Two of the three lobes have been excavated for limestone. You can also see smaller pinnacle reefs marked with the short arrows. All of the reefs rise above the flat Texas landscape. (Permission from Google.com: ‘Special Use Guidelines’.) Fossils We spent a lot of time at the quarry observing the massive specimens onsite and then collected some smaller pieces to bring home and look at closer. A simple way of thinking about fossils is to consider them either as a cast or a mould. A mould is formed when an object is placed into a soft substrate and then decomposes or is washed away … Read More

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Disappearing Dunwich

Roy Bullard (UK) There are many places around the coastline of the British Isles that are quite simply majestic and, in their own unique ways, full of magic. Dunwich lies between the lovely town of Southwold and the village of Sizewell on the East Coast of England in the county of Suffolk. It is a coastal area that is easy to include in this category and is a place that I love to visit. However, as you sit there on the shore watching the cliffs and the North Sea, it is hard to imagine that so much has been lost since the time when Dunwich was once a large, thriving community. Fig. 1. Sandy cliffs of Dunwich. My aim in this short article is to take a look at the present state of this coastline and compare it with the coast as it once was before huge amounts of coastal erosion had taken place. In addition, I will take a look at the area’s history and mention, in passing, one of its well-worked, mythical tales. A steeply sloping shingle beach now lies in front of the cliffs at Dunwich. These cliffs have changed a lot over time but, over the past few years, erosion has decreased substantially. The cliffs today are overgrown and this indicates a significant slowdown in the rate of erosion. However, with the ongoing threat of climate change and rising sea levels, the local residents and council have joined together to act now to protect the northern … Read More

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Collecting sharks’ teeth at Herne Bay, Kent

Les Lanham (UK) Just to the east of Herne Bay in Kent, on the way to Reculver at Beltinge, there is a small area on the foreshore where fossils of shark and other fish remains can be found on a good low tide. As this is a beach location, success will depend on good, local conditions but, if favourable, a good number of fossil teeth can be found. In fact, Beltinge is one of the best areas in Britain to collect such teeth and it is not unusual to find 20 to 30 persons on the beach on very low tides. Even so, everybody there could end up with a good haul of material by the end of the day. Fig. 1. Four keen geological groups meet for the annual extreme low tide event. I have set out directions at the end of this article detailing where to start your day. From this starting point, go as far out as the tide will let you and shark teeth can be found. Indeed, the chances of finding teeth improve the further out the tide goes. Broadly speaking, the collecting area is in the section of beach between the groynes either side of the concrete steps. Here, when the tide has gone out quite a distance, there appears to be a “stream” running out to sea. This is the junction between the clay beds to the west and the shingle to the east. Fig. 2. Thanet Beds exposed east of Herne Bay. … Read More

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Prominent figures of the 1800s who gave rise to vertebrate palaeontology

Megan Jacobs (UK) For centuries, the creatures of the past, from the terrifying theropod dinosaurs to the tiny early mammals, have captured the imaginations of millions. However, the people who put those beasts into the limelight are rarely acknowledged for their work and, in many cases, remain unknown. So here is a short account of some of the first prominent names in the world of vertebrate palaeontology, their contributions to the field, and an insight into the often eccentric behaviour that came with it. Georges Cuvier (1769-1832) Fig. 1. Georges Cuvier.Georges Cuvier was a French naturalist and zoologist, and is regarded as the ‘’father of palaeontology’’. He was one of the finest minds in history, founding vertebrate palaeontology as a scientific discipline. For example, in 1800, he identified Pterodactylus as the first known pterosaur from a print published by Alessandro Collini. Shortly after, he described the first mosasaur, a giant marine reptile that was brought to France by Napoleon after he conquered the Netherlands. Going against his old Christian (Catholic) upbringing, Cuvier believed the Earth was immensely old and, during its history, underwent abrupt changes that Cuvier called ‘revolutions’, in which large numbers of species were wiped out. This was the first recognition that extinctions were facts. Cuvier also rightly speculated that there had been a time where reptiles had been the dominant animals on the planet. Indeed, the decades after his death yielded spectacular finds that confirmed his theory. After a study comparing modern elephant species, he worked on … Read More

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Stop the press: The Jurassic Coast starts in the Permian

Mervyn Jones (UK) This Geologists’ Association field meeting followed the publication of Professor John Cope’s Geologists’ Association (GA) Guide No 73, Geology of the South Devon Coast. It is also the companion to GA Guide No 22, Geology of the Dorset Coast. John retired in 2003 after lecturing at Swansea and Cardiff universities. Since then, he has been an Honorary Research Fellow at the National Museum Wales in Cardiff, and has a wide field experience in the UK and Europe, with publications covering many fossil groups over a wide stratigraphical range. Most recently he has been working on redrawing the geological map of South Wales, the subject of an upcoming GA lecture. And, each year, for the past six years, he has provided weekend geological trips to the West Country. Fig. 1. Prof Cope demonstrates bedding and cleavage. We met up at Meadfoot Strand to the east of Torquay Harbour. Our mission for the weekend was to examine the complex Devonian succession in the Torbay area and its unconformable relationship to the Permo-Triassic cover. Of great interest was the marine Devonian, first described by Adam Sedgwick, assisted by Roderick Impey Murchison, who finally realised that these facies were contemporaneous with the familiar Old Red Sandstone found north of the Bristol Channel. Since then, the Devonian Stages have been named after rocks in the Czech Republic, Germany and Belgium. The base of the Devonian was the first ‘Global Boundary Stratotype Section and Point’ (GSSP), defined by graptolite zones at Klonk, in … Read More

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Rocks in Roslin Glen: A record of a swampy past

Mark Wilkinson and Claire Jellema (UK) Midlothian is an area of central Scotland that lies to the west of Edinburgh and is an area with strong geological connections due to a history of mining for both coal and oil shale. As a part of the annual Midlothian Science Festival (http://midlothiansciencefestival.com/), the School of GeoSciences at the University of Edinburgh offered a walk to look at some local geology and a talk about climate change research on the Greenland icecap. In addition, a ‘Dino and Rocks Day’ was attended by 380 people, proof (as if it were needed) that dinosaurs continue to fascinate the general public. The Edinburgh Geological Society also contributed with a session about Midlothian Fossils and a local historian talked about the history of coal mining in the area. The geology walk visited local exposures, in this case Carboniferous sediments including what may be the best exposed fluvial sediments in the area. The walk was advertised as “Rocks in Roslin Glen: a Record of a Swampy Past” and all 25 spaces were quickly booked. The location was Roslin Glen, which may sound familiar if you’ve seen the film, The Da Vinci Code, based on the novel by Dan Brown. We have not misspelled the name of the glen incidentally. For some reason, Rosslyn Chapel lies on the edge of Roslin Glen and the country park of the same spelling. The glen itself is a steep-sided valley of around 20m in depth, which carries the River North Esk roughly … Read More

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Colourful bluffs in Long Island recall the most recent ice age

Deborah Painter (USA) Imagine a tremendous piece of land moving equipment that scraped up the soil and some of the surface bedrock from four states within the United States’ Eastern Seaboard, carrying and dragging it all the way, before dumping it on a ridge off the shoreline. That is what essentially occurred with the final advance of the Wisconsinian ice sheet, the only one which left glacial deposits visible in New York State today. Long Island is a ridge of Cretaceous bedrock with glacial deposition. The moraines there have not been ground into sandbars and spits along the western end of the north shore as much as elsewhere, because of the sheltered nature of the Long Island Sound. Therefore, shoreline bluffs expose rocks as well as glacial loess. Fig. 1. Fishermen’s Drive takes you to the loess deposits. To park at the beach requires a permit. (Photo by JB Steadman.) If you find that your journeys take you to New York City, one of the world’s largest metropolitan areas, try to make time to visit Caumsett State Park at Long Island Sound. My own visit began when planning a visit to New York State’s Long Island to see my friend, Joyce Raber. She suggested various things that we might do: go to a Broadway play, go shopping and so forth. However, my list of things to do was typically “eco-tourist”. I wanted to visit the famed American Museum of Natural History in Manhattan, then see nearby Central Park, where the … Read More

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Triassic beasts and where to find them

Sue Beardmore (UK) Located amid the scenic Southern Alps, on the Swiss-Italian border, is Monte San Giorgio, a mountain that rose up like many across Central Europe as a result of continental collision between Africa and Europe during the Alpine Orogeny. It is not particularly big or distinct by alpine standards but it is special, a status emphasised by the designation of its slopes as a UNESCO World Heritage site initially in 2003 for the Swiss part with the neighbouring Italian area added in 2010. To begin, the rocks outcropping on the mountain form an almost complete stratigraphic sequence from the Permian through to the Jurassic (Fig. 1), not only an extended interval of time but an important one around the massive Permo-Triassic extinction. The same rocks provide a context for the equally important Middle Triassic vertebrate, invertebrate and plant fossils, now numbering more than 20,000, that have been found at the locality over the last 170 years. Fig. 1. A stratigraphic section of the rocks at Monte San Giorgio. © Commissione Scientifica Transnazionale Monte San Giorgio, 2014. In particular, it is the diversity, relative abundance and excellent preservation of the vertebrate fossils that has thrown the locality into the spotlight. These occur in six main fossiliferous horizons deposited in a shallow marine basin, the Monte San Giorgio Basin, one of many depressions on a carbonate platform between the Eurasian continent to the north and west, and the open waters of the vast Tethys Ocean to the south and east. … Read More

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Whitby Jet and the Toarcian Oceanic Anoxic Event

Arthur Speed (UK) One hundred and eighty million years ago in the Toarcian Stage of the Lower Jurassic Period, the Earth was very different from the world we know today. The continents were all clumped together in a supercontinent called Pangaea, which was just beginning to split apart. Sea level was approximately 100m higher than at present, such that much of Britain (including Yorkshire) lay beneath shallow seas. At this time, the Earth’s oceans were depleted in dissolved oxygen. The chain of events that caused this are complex, but can be traced back to a major volcanic event (Fig. 1). The eruption of the Karoo-Ferrar Large Igneous Province (LIP) spewed lava over what is now southern Africa and released vast amounts of carbon dioxide into the atmosphere. Just as happens now, the carbon dioxide resulted in global warming, which, in turn, had several effects on the oceans: Fig. 1. Volcanism during the eruption of the Karoo-Ferrar LIP may have triggered the Toarcian Oceanic Anoxic Event (Ulrich, 1983). Seawater became deficient in dissolved oxygen, because oxygen solubility decreases with increased temperature.Plankton thrived as a result of the warmer temperatures and increased nutrient supply, using up even more dissolved oxygen.Oceanic circulation was decreased, reducing the supply of cold oxygenated water to the oceanic basins.Warmer water released the green-house gas methane from the ocean floor, further accelerating global warming.The result was the formation of a layer of water that was deficient in oxygen throughout the Earth’s oceans. Its existence was first postulated in … Read More

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Daily lives of fossil reptiles

Robert Coram (UK) The Mesozoic and Cenozoic deposits of Southern England have long been a rich source of fossil reptiles. Past finds of great historical importance include some of the earliest known examples of dinosaurs, ichthyosaurs and pterosaurs. Fossil material, including new species, continues to be revealed, mainly at rapidly eroding coastal sites. All these reptiles would have been active participants in their local ecosystems, whether on land or in the sea. Much information about the roles they played and their interactions with other organisms can be gleaned from their skeletal anatomy and from comparison with living relatives such as crocodiles. What this article is concerned with, however, is evidence of specific incidents in the lives, and deaths, of individual reptiles; tiny snapshots of opportunities, mishaps and the daily drudge of staying alive. These add more detail and colour to our knowledge of the lifestyles of these long-vanished animals. This evidence will be provided by four selected terrestrial and marine deposits from southern England, spanning the last quarter of a billion years of Earth history (Fig. 1). Fig. 1. Geological map showing locations of deposits discussed in the text. (1) Triassic Otter Sandstone of South Devon; (2) Jurassic Lower Lias of the Somerset (a) and Dorset (b) coasts; (3) Cretaceous Wealden beds of the Isle of Wight (IOW on map); and (4) Paleogene Hamstead beds of the Isle of Wight. Trace fossils in a desert world – the Triassic Otter Sandstone Rocks dating from the Triassic period, laid down between … Read More

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Finders, keepers: The lost world of some Isle of Wight geological heroes

Martin Simpson (UK) There is a growing misconception that most of the earliest important fossil discoveries were made by a select few famous geologists – established names, who were supposed to have ‘found’ everything in their collections. In reality, however, the true ‘discoverers’ of the original specimens were an often unknown or forgotten assortment of amateurs, labourers, beach-combers, longshoremen or quarrymen: opportunists, who were finding ‘new’ material with surprising regularity. These people not only had local knowledge, but also had the distinct advantage of being in the right place at the right time, thanks to the hours they devoted to searching. On the other hand, the early geological pioneers were fervently adding to their private museum cabinets by whatever means possible. As news of major finds of unusual fossils came to their attention, perhaps by way of the reports in some of the provincial broadsheets mentioned later, the more diligent and successful collectors (the acquirers) put their money where their mouths were and purchased directly from the sources (the finders). Eventually some of this material found its way to the academics and their institutional museums (the keepers). In the case of the Isle of Wight – that classic locality for Cretaceous and Palaeogene fossils – the earliest and most important historical discoveries have been attributed to a small group of generalised geologists. These include William Buckland, Adam Sedgwick, William Fitton, Edward Forbes and the surgeon, Gideon Mantell between the 1820s and the 1850s; and later to a whole host of … Read More

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Dendermonde Mammoth: Fighting pyrite decay and the preservation of unique palaeontological heritage

Anthonie Hellemond (Belgium) Collecting fossil vertebrates is rather popular among amateur palaeontologists. However, little interest is shown in the different stages one should undertake to treat and safely guard these specimens for the future. Loads of fossils from historical collections are currently suffering because of years of storing and neglect. This might seem strange, since the fossils themselves have spent most of their time underground in very humid conditions, but in reality, problems only start right after digging them up. Following-up on the restoration project of the “Dendermonde Mammoth”, we want to give an insight into the problems one can encounter when dealing with the restoration and preservation of Pleistocene vertebrate remains that have remained untreated for the past 20 years. The discovery In the historical Belgian city centre of Dendermonde (French: Termonde), we find the city’s history (including natural history) museum called the “Vleeshuis” museum (the house of meat merchants). It is located in one of the most authentic sandstone buildings in the main market square of “Dendermonde” (a province of East-Flanders). Inside the majestic wooden attic of the museum, the city’s oldest resident watches over the collection, which is packed with fossils and artefacts from the last ice age and prehistory. When walking up the impressive stone stairs that lead to the attic, visitors will encounter the paleontological pride of the “Dender” valley (the river flowing through Dendermonde). When we take a closer look at the information signs, we learn that this mammoth was found between 1968 and … Read More

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Tully Monster: Is this the world’s most mysterious fossil?

James O’Donoghue (UK) The Tully Monster is a mysterious 307Ma-old marine animal known only from the famous Mazon Creek fossil locality in Illinois. Its body plan is unlike any other animal that has ever lived, and it has been subject to wildly different interpretations as to its identity since its discovery in 1955. Last year, Victoria McCoy of Yale University and colleagues identified it as a lamprey, a primitive type of fish, but this has since been challenged by a team of vertebrate palaeontologists. Fig. 1. Reconstruction of a Tully monster based on the research of McCoy and colleagues. The claw and proboscis are on the right and its eyebar and eyes, gills and tail fin are further back. (Sean McMahon/Yale University.) Fossil collector Francis Tully knew he had made an extraordinary discovery. Inside a rounded nodule was a bizarre, foot-long animal with a long trunk and claw. But he could never have known quite how extraordinary his 307Ma-old fossil would turn out to be. Sixty two years later, scientists are still arguing over the basics as to what sort of creature it really was. What makes it even stranger is that this is no rarity known only from fragmentary remains. After Tully made his find, word got around among collectors and, before long, hundreds more had been found. Tullimonstrum gregarium, or ‘Tully’s common monster’, is now known from well over a thousand fossils, including many complete specimens. “We’ve got four cabinets of Tully monsters here, each of which has … Read More

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Highlights from the Museum am Löwentor in Germany

Jack Wilkin (UK) The Museum am Löwentor in Stuttgart, Baden-Württemberg, is one of the world’s greatest depositories of fossils. The museum was founded in 1985 and, since then, it has built up a vast collection of over 4.1 million fossils and has a 3,500m2 exhibition space, spilt over two levels. It is organised in chronological order. As you progress through the building, you can trace the evolution of life on Earth from the first cells all the way to the present, telling a more-or-less complete story of Germany’s geological history. This brief article will focus on just a few of the highlights at the museum. The amber collection The museum houses roughly 30,000 amber specimens from around the world, including samples from the Dominican Republic, the Baltics and the Lebanon, to name just a few places. The highlights of the collection include the largest piece of amber in the world from the Miocene of Borneo, as well as the world’s biggest damselfly and dragonfly inclusions. Triassic vertebrates There is an extensive collection of Triassic vertebrates from Baden-Württemberg, including, not just complete skeletal reconstructions, but also realistic life models. Fig. 1. Exhibits at the museum.One group that is featured in the exhibit were the placodonts – an enigmatic group of marine reptiles that superficially resemble turtles, although the two groups are unrelated. Many species, such as Placodus gigas, had large, flat teeth designed for crushing shells. The apex land predator of Central Europe at the time was the 5.6m, Batrachotomus. It … 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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Aetosaurs: An introduction

Stephen Lautenschlager (Germany) The Triassic Period was one of the key episodes in the evolutionary history of life. It marks the transition from the Palaeozoic to the Mesozoic Era, preceded by the Permian/Triassic mass extinction – the greatest extinction event of all time. A conclusive explanation for it has still to be found, but it is presumed that massive eruptions of flood basalts in Siberia were a key factor. The resultant release of green house gases, such as carbon dioxide and sulphur dioxide, into the atmosphere may have led to a catastrophic rise of the global temperature and oxygen depletion. While other causes may have contributed to this extinction, its effects are clearly visible in the fossil record. Over 90% of marine species and about two thirds of terrestrial species died out. Among the tetrapods, amphibians and therapsids (mammal-like reptiles) suffered the most and the terrestrial ecosystems were heavily depleted. Fig. 1. Life restoration of Desmatosuchus, a heavily armoured aetosaur from North America. Yet, on the other hand, this mass extinction cleared the way for several new groups of animals. The ecological niches on land, which had been vacated since the Permian/Triassic transition, were quickly occupied by two new groups – the rhynchosaurs and the archosaurs. The latter proved to be most successful, not least for the rapid evolution and diversification of the dinosaurs in the Late Triassic, which eventually gave rise to the birds. However, it was other groups among the archosaurs, which first took advantage of the newly … Read More

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Colossal tortoises: Climate change and the evolution of Europe’s largest ‘modern’ reptiles

Benjamin Kear (Australia) and Georgios Georgalis (Greece) Most people are familiar with the famous giant tortoises of the Galapagos Islands – isolated oddities evolving in the absence of predators on a remote tropical paradise. However, as little as 5mya, continental landmasses (including Europe, Africa and India) also had their own species of giants. However, these were nearly three times the size of their modern cousins, probably close to the mass of a small car, and would have rivalled some dinosaurs for being among the most colossal reptiles of all time. Fig. 1. A life-size reconstruction of the European gigantic tortoise Cheirogaster as displayed in the University of Athens Palaeontological and Geological Museum. This model represents a massive individual of a carapace length of around 2m and was based on finds from Pikermi, near Athens, and the island of Lesvos. The best preserved gigantic tortoise fossils (as opposed to the merely ‘giant’ ones) have been found in Mediterranean Europe, particularly France, Greece and Spain, and were described in the scientific literature as early as 1877. Yet, despite an impressive chronicle of discoveries, the inter-relationships between these different kinds of gigantic tortoises are far from adequately understood. The present, albeit tentative, consensus is that there are at least three separate lineages, all of which achieved maximal body size at about the same point in geological time. Cheirogaster, the genus found in Europe, has a long fossil history stretching back some 50mys to the Eocene and includes up to 11 species. It is … Read More

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Collecting fossils in Florida

Niels Laurids Viby (Denmark) I didn’t go to Florida especially to look for fossils, but I am always looking for opportunities when I am abroad. Being an architect, I actually went there to study houses, in particular, the Art Deco district at Ocean Drive in Miami. However, it seems that every museum in the State (other than art museums) has a fossil exhibition: the Science museum in Miami was showing Chinese dinosaurs, the Orlando Science Centre had displays of Upper Cretaceous dinosaurs and the Natural History Museum in Gainesville had the very best – complete skeletons of mammals from Florida. Fig. 1. Fossil exhibition with complete skeletons of mammals from Florida, at the Natural History Museum in Gainesville. The result was that I spent a lot of time looking at things (including buildings) rather than finding fossils. In fact, out of thirteen days in Florida, I spent three in or waiting for planes, four driving long distances (but with some stops checking out potential fossil sites), four looking at houses, one on paperwork for a report on buildings and only one full day looking for fossils. The time spent driving was a big surprise. Florida looks small on a map of USA, but all of Denmark (my home country) could fit into the area south of Gainesville and the Danish population is probably equal in number to half of the people living in Greater Miami. However, I saw this trip as an expedition into unknown territory – a future trip … Read More

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