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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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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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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Akal Wood Fossil Park, Rajasthan, India

Khursheed Dinshaw (India) The Akal Wood Fossil Park is located about 18km from the desert city of Jaisalmer in Rajasthan, India. It has preserved fossil evidence dating back to the Jurassic Period (Fig. 6) indicating a hot and humid climate characterised by dense forests. In particular, 180-million-year-old fossils of animals and plants are preserved here. Fig. 1. The fossilised logs have been protected by iron grill cages with overhead tin sheds. The Jaisalmer Basin formed part of the southern shelf of the Tethys Ocean during Jurassic times. The area is well known for its rich geo-diversity, both in terms of landscapes and outcrops of rock types, and the variety of fossils that these rocks have preserved. When I spoke to him, Dr Sudesh K Wadhawan, who is Adviser (Geosciences) and Visiting Faculty, Director General (Retired), Geological Survey of India, explained that, “Lithostratigraphy of the geologically mapped formations displays an array of Jurassic siliciclastic, mixed carbonate-siliciclastic and carbonate rocks that range in age from Lower Jurassic to Upper Jurassic in geological timescale. A variety of depositional environment, ranging from continental fluvial to near-shore and off-shore deep marine, are interpreted and well documented in the Jaisalmer basin”. Fig. 2. Fossilised tree trunks lying scattered in an area of 21 hectares. The fossil logs, representing gymnosperms, belong to the dicotyledonous stems of these trees (Figs. 7 and 8). (In such stems, the vascular bundles are arranged in a ring, with pith concentrated at their core, rather than being scattered throughout the plant interior.) … 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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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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Rock paintings of Bundi, India

Khursheed Dinshaw (India) The River Rewa bifurcates into the Ghoda Pachad and Mangli Rivers while flowing through the region that is located 33km to the south of Bundi, in the state of Rajasthan, India.Probably the world’s largest rock paintings can be found in the rock shelters along the banks of the Mangli River here. They belong to the Mesolithic and Middle and Upper Palaeolithic periods, and depict hunting scenes – the life of gatherers, human stick figures, bulls, antelopes and wildlife (Fig. 1). Cultural scenes portray dancers, musicians and daily life. There are also inscriptions made from the plant Brahmi on the sandstone rocks lining the River. The rock shelters stretch across a distance of almost 35km. Fig. 1. Animals depicted in one of the rock shelters, which is part of the world’s largest rock painting site. Om Prakash Sharma, also known as Kukki, a local resident of Bundi is credited with discovering this site, as well as nearby sites. On 4 December 1993, he explored a Chalcolithic (Neolithic) mound in the village of Namana, where he found terracotta toys, an axe and chisel. While investigating these discoveries, a historian suggested that he try to locate rock paintings. As a result, for three years, he spent most of his time near rivers and boulders in the hope of locating rock paintings, but with no success. Not one to give up, he continued looking. Even in his dreams, it was always mountains and rock paintings that he envisioned. In one of … Read More

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Gravel sheets in the suburbs of Washington, DC

Deborah Painter (USA) If you live in western Prince George’s County, Maryland in the USA, in the towns of Oxon Hill and Suitland and you want to dig to place a water line, plant a garden or excavate to construct a foundation for any building, chances are you will encounter sandy soil with hundreds of cobbles and boulders. Some boulders encountered could be in the form of large flattened slabs. You might be wondering why these are present, since these towns are in a coastal plain, far south and east of the rocky outcrops of the Piedmont area of Virginia and Maryland. For someone like me, who was born and raised in the Coastal Plain area of Virginia, these ubiquitous cobbles and boulders seemed out of character for the region. I discovered these odd boulders and cobbles when I joined a colleague from an office in a northern state to assist him in ecological studies for two small sites not too far from the United States Capital of Washington, in the District of Columbia (DC). Our goal was to help our client know if there were any threatened or endangered species, wetlands, hazardous materials or other site constraints, as this would assist the client to decide whether to purchase the properties. Our first Prince George’s County site for an ecological study was one of a few hectares in size in Suitland, a suburb of Washington, DC and approximately 8km southeast of the border of the capital city near the shore … 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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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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Clarkia Flora: 16-million-year-old plants offer a window into the past

Margret Steinthorsdottir and Helen K Coxall (Sweden) Near the small town of Clarkia in Shoshone County, Idaho in the USA, exists a rich and unique fossil deposit. The Clarkia fossils, or Clarkia Flora, as the deposit is mostly called due to the abundance of fossil plants, is so well preserved that the assemblage is referred to as a “lagerstätte”, a scientific term reserved for the world’s very finest fossil deposits. The Clarkia fossils are found in sediments that are now known to be about 16 million years old and belong to a period in Earth history called the Miocene. By this time, the (non-avian) dinosaurs were long extinct (the last of these dinosaurs disappeared about 66 million years ago), the Earth’s continents were more or less in the same position as today, and many of the animals and plants would have started looking familiar to modern humans (who emerged much later, about 200,000 years ago). Fig. 1. The entrance to the “Fossil Bowl” motocross racetrack and fossil locality near Clarkia, Idaho. Among the Clarkia fossils can be found various insects, fish and occasionally the remains of small mammals. However, most striking is the wealth of plant fossils in the form of exceptionally well-preserved leaves, nuts, seeds and wood. Impressively, one can find leaves of oak, laurel, pine and birch that look virtually identical to those we find today. If you look quickly when a new fossil is newly exposed from within the host sediments, you may occasionally even see the … 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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Bryozoans in the English Chalk

Dr Paul D Taylor (UK) We are very fortunate in Britain to host one of the most remarkable deposits in the entire geological record, the Chalk. The Late Cretaceous Chalk (with a capital ‘C’) is an extremely pure limestone, famous for the White Cliffs of Dover and responsible for the landscape of rolling hills and dry valleys, forming the ‘downs’ and ‘wolds’ that stretch through England from Devon in the southwest, to Yorkshire in the northeast. The economic importance of the Chalk to the early human inhabitants of Britain was enormous because the flints contained within it could be fashioned into axe heads and hard cutting tools. Why is the Chalk so special geologically? It is a rare example of a pelagic sediment – an open ocean sediment – that was deposited over the continental shelf. This occurred at a time when global sea-level was high and the supply of terrigenous clastic sediment into the sea was minimal. The Chalk is an oceanic ooze composed mainly of the disaggregated plates – coccoliths – of coccolithophores, planktonic microalgae with exquisitely engineered skeletons of calcite. Unfathomable numbers of coccolithophores sank to the seabed over a period of some 35 million years to produce the thick accumulation of Chalk that today extends over northern Europe and into western Asia. The Chalk is a favourite hunting ground for fossil collectors, yielding beautifully preserved specimens, especially of echinoids. But closer inspection of the Chalk shows that the dominant macrofossils are often bryozoans. These colony-forming invertebrates … Read More

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Urban geology: The strange tale of a windowsill

Stephen K Donovan and John WM Jagt (The Netherlands) Leiden, in the Dutch province of Zuid-Holland, is a city with a fine selection of fossiliferous building stones, mainly Mississippian (Visean, Lower Carboniferous) limestones. which preserve an array of fossils, such as rugose and tabulate corals, brachiopods, bryozoans, molluscs, and crinoids. However, this fine diversity of body fossils is not supplemented by a similar composition of trace fossils. Despite having examined these rocks over many years, when leading student fieldtrips and in collusion with co-workers, SKD has found no evidence of burrows, nor any borings in bioclasts, which can be locally common at some localities where Mississippian strata are exposed (for example, Donovan and Tenny, 2015). It is therefore of note to recognise an uncommon rock type among the building stones of Leiden that is dominated by burrows and lacks body fossils. This article highlights this distinctive building stone that has engrossed SKD for some years. The street Rapenburg (Fig. 1) in Leiden is a favourite route for building stone tours of the city. Although the dominant building materials are bricks, there are ample rocks to make a visit worthwhile. When SKD has led groups of students from the University of Leiden on geological excursions down the Rapenburg, the start is commonly at the North End Pub (Fig. 1). Fig. 1. Map of the centre of Leiden (modified after Van Ruiten & Donovan, 2018, fig. 1); Leiden Centraal railway station is north of the north-west corner of this map and less … 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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Three-dimensional photographs of fossils (Part 2): Stereophotography of ancient micro-organisms

Dr Robert Sturm (Austria) In the past 60 years, microfossils have increasingly attracted the attention of earth scientists for several reasons. Firstly, they are highly useful in biostratigraphic respects; secondly, they can be easily determined by light- or electron-microscopic studies in most cases; and thirdly, sampling, preparation and storage of microfossils is carried out according to well-defined and mostly simple procedures. By definition, microfossils are the petrified relics of micro-organisms, which have mainly colonised aquatic habitats of the Tertiary or older epochs of earth history. Most of these ancient micro-organisms measured less than 1mm in size, so any scientific documentation of their remains requires a magnifying glass or, better still, a microscope. In certain cases, the size of microfossils is between 10µm and 100µm, which necessitates the use of an electron-microscope to elucidate their structure and to determine the species. Fossils measuring less than 10µm in size chiefly belong to another category of fossils, that is, nannofossils (for example, coccoliths). Typical representatives of microfossils include radiolaria, foraminifera, ostracods and diatoms, which may be used as index fossils within certain local or regional strata. A special role is taken by conodonts, which are small dental structures belonging to the so-called ‘conodont animal’. This is supposed to be distantly related to the lancet fish (Brachiostoma). While foraminifera, radiolaria and ostracods have colonised the earth with varying abundances since the Early Cambrian (570Ma), the occurrence of conodont animals seems to be restricted to the time period ranging from the Middle Cambrian (about 550Ma) … Read More

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Headbanging, rocking and moonwalking fossils

Mats E Eriksson (Sweden) One can never be too careful when given the opportunity to name a fossil organism that has proved to be new to science. In addition to a meticulous description and accompanying images showing the characteristic traits of the fossil, a unique and formal, Latinized scientific name must be attached to the creature. Many people, who get the chance honour an older colleague or famous palaeontologist, use the name of the discovery site or region to indicate the provenance of the fossil or, of course, christen the fossil after its characteristic looks (for example, Eriksson, 2017a). But you can also glance towards completely different areas, such as the art and music scenes. As a lifelong music fan and hobby musician (who, just like many of my peers, had aspiring yet quite ludicrous ‘rock star dreams’ in my teens) and a palaeontologist by profession, I cannot help myself but feeling blissful and delighted about the possibility of joining my two passions – ‘heavy’ music and palaeontology – in ‘unholy matrimony’. This has, among other things, led me to name some extinct polychaete annelid worms (bristle worms – the marine ‘cousins’ of earth worms and leeches) from the Silurian and Devonian periods after some of my favourite ‘metal’ musicians. These largely soft-bodied animals generally have poor preservation potential, although full body fossils are known from the fossil record. However, some representatives are equipped with resistant jaws (when preserved as microfossils they are known as scolecodonts) that, by contrast to … 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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Boxstones: In search of Miocene Suffolk

Tim Holt-Wilson (UK) The date is 24 May 2014 and I am browsing across East Lane Beach at Bawdsey in southeast Suffolk. A brown lump of sandstone with a white fossil shell impression catches my eye. A boxstone. This is the first one I have ever found with a fossil in it. Looking closely, I see that the sea has abraded the shell’s outlines, although the margins have survived better than the rest, so it should be possible to identify the specimen (Fig. 1). Fig. 1. Boxstone, found 24 May 2014. Boxstones are fragments of a vanished world. They are all that remains of a lost geological stratum in Suffolk called the ‘Trimley Sands’ (Balson, 1990), although deposits of similar age are still present across the sea in Belgium and other parts of Europe. Boxstones are lumps or concretions of brown sandstone, which may contain shell fossils and – if you are extremely lucky – bones and teeth. They are beach-rolled and rounded, and typically measure between 5 and 15cm in diameter. The sand is mostly quartzose, with a rich assemblage of secondary minerals, and is cemented with carbonate-fluorapatite (a phosphate mineral) and calcite (Mathers and Smith, 2002). Boxstones can be found scattered sparsely across the shingle beaches at Bawdsey and Felixstowe Ferry (Fig. 2), and in situ as a common component of the basement beds (nodule beds) at the base of the Coralline Crag and Red Crag formations of southeast Suffolk (Fig. 3). They are eroding out of the … Read More

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Heavy Metal painter meets Heavy Metal palaeontologist: The conception of an unusual portrayal of the past

Mats E Eriksson (Sweden) Sometimes, the stars just seem to align perfectly and make you appreciate life more than at other times. You know those ephemeral moments when, all of a sudden, you find yourself in the midst of something that you would not have dared dream about. All your favourite aspects of life are suddenly combined into a giant melting pot and once the metaphoric molten steel hardens, you are left with the most stunning and unexpected new kind of precious metal. For me, this happens when music, arts and palaeontology unorthodoxly merge (Eriksson, 2016); and more specifically in this case, when exceptionally preserved, miniscule Cambrian arthropods had their first encounter with, and ‘sat for a portrait’ for, an iconic ‘metal’ painter. Besides my profession as a palaeontology professor at Lund University in Sweden, I have a major soft spot for the arts and music. As a matter of fact, in some aspects of my professional life, I have had (or created) the opportunity of actually combining these long love affairs. When it comes to scientific outreach, I am involved in a traveling exhibition on fossils named after rock stars (‘Rock Fossils’; Eriksson, 2014a) and I have named fossils in honour of some of my favourite musicians (Eriksson 2014a, 2017; Eriksson et al., 2017). I also record music based on palaeontological research results together, with established metal musicians (for example, Eriksson, 2014b; https://kalloprionkilmisteri.bandcamp.com/releases). Granted, this might be viewed as exceedingly eccentric and something that you perhaps think does not … Read More

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Colorado mountain memories

Steven Wade Veatch (USA) While headed for the California Gold Rush of 1849, George Giggey (who was my great-great-grandfather) first made his way through the mountainous and untamed wilderness of what would later become Colorado. He was among a group of young men, who were determined to make a new life, fortune and future in the American West. After working in the Californian goldfields, he turned his attention to Colorado, where he prospected for gold for a while and then returned to the East. In 1865, George Giggey returned to Colorado with his family of ten children and built a homestead in the wilderness near what would become, in just a few years, the town of Caribou. The town developed around the Caribou silver mine that was discovered by Sam Conger in 1868. George Lytle, one of Conger’s partners, was from British Columbia and named the mine after his caribou hunting trips in Canada. By 1870, the Caribou Mine was in full production and was shipping ore down Coon Trail, to the nearby settlement of Nederland for processing. By 1872, the frontier town of Caribou built a much needed schoolhouse. Three of George Giggey’s boys attended Caribou’s first school session. They were: George Leon (my great-grandfather), who was 14 years old; Adelbert, age 7; and Charley, who was only 6 years old. I can feel the boy’s excitement when they took their seats in the one-room schoolhouse, with new furniture, blackboards, maps, globes and a new teacher – Miss Hannah … 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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Carbonate platforms and coral reefs: The Coralline Oolite of the Yorkshire Upper Jurassic – a prime source of palaeontological information

Keith Eastwood (UK) The Malton Oolite Member of the Coralline Oolite Formation (Corallian Group), as exposed in the Betton Farm South Quarry (TA00158555) at East Ayton, near Scarborough (Fig. 1), provides a wealth of fascinating palaeontological and sedimentological information. Examination of outcrops within this small quarry enables the geologist to reconstruct the palaeoenvironment of deposition of the Betton Farm Coral Bed, a localised system of patch, ribbon and framework reefs that developed during the Upper Jurassic. Fig. 1. Locality map of the Betton Farm and Spikers Hill quarries. Geological outcrops from BGS Sheet 54 (Scarborough) (1998), (Wright, 2001, p.157, fig.4.20). Total image © Joint National Conservation Committee; geological outcrop map – British Geological Survey © NERC. Redrawn and reproduced with permission. The lithology and textural characteristics of the Malton Oolite Member provide a sedimentological basis for the interpretation, but the fossil content adds definitive ecological and climatic insights. The Malton Oolite is the upper of two oolite members in the Coralline Oolite Formation (Fig. 2). The lower one, the Hambleton Oolite Member, is not seen in the Betton Farm Quarries (which consist of two quarries: Betton Farm North Quarry and Betton Farm South Quarry, north and south of the A170, respectively) but is fully exposed in the Spikers Hill Quarry (SE 980863) just 3km to the WNW (Fig. 1). This location is important in providing a regional depositional context for the Betton Farm deposits, even though the upper surface of the intervening Middle Calcareous Grit Member is a minor unconformity. … 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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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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Fossil folklore: Molluscs

Paul D Taylor (UK) The final article of this series on fossil folklore focuses on molluscs, excluding the ammonites, which were covered earlier (see Fossil folklore: ammonites in Deposits, Issue 46, pp. 20–23). Molluscs are second only to arthropods in the number of species living today and the resistant calcareous skeletons possessed by the majority of species accounts for their extremely rich fossil record. Most fossil molluscs belong to one of three major groups – bivalves (oysters, clams and so on), gastropods (snails and slugs) and cephalopods (ammonites, belemnites and so on). Added to these are a few minor groups, such as the monoplacophorans and scaphopods (tusk shells). Fossil molluscs are usually recognisable instantly as belonging to this phylum because of their close similarities with the shells of familiar species of modern molluscs. Some, however, are not quite so straightforward. These are more likely to have been the sources of fanciful stories about their origins and significance. Among the more obscure ancient molluscs are those dubbed ‘difficult fossils’ by Martin Rudwick in the context of the early history of palaeontology and doubts over the origin of fossils. They include the solid internal casts (steinkerns) formed by lithification of sediment enclosed by the shell and subsequent loss of the defining shell itself. In addition, there are some mollusc fossils – notably belemnite guards – that bear little resemblance to any living species, adding to their enigmatic nature. Belemnites: thunderbolts and Devil’s Fingers The first fossils I ever came across were belemnites … Read More

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