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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Very down-to-earth Vasquez rocks portray the surface of alien planets for the media

Deborah Painter (USA) They have become associated with stark alien or other-dimensional landscapes since the 1960s, when the popular American television programme Star Trek used them as dramatic backdrops in two episodes, “Arena” and “Friday’s Child”. Prior to that, the Vasquez Rocks of Agua Dulce in California were a favoured location for American Western programmes, such as Branded, Cheyenne, Zorro and The Adventures of Champion, as well as motion pictures like One Million BC (1940) and Apache (1954), when rocky areas with hiding places, wide overlooks and an overall arid, rugged look were needed. More recent films and television programmes tend to exploit their odd appearance (Star Trek IV: The Voyage Home (1986), Army of Darkness (1993) and John Carter (2012)). Some films with no fantasy elements also use the rocks as a backdrop, one example being the family “road” comedy, Little Miss Sunshine, released in 2006. Fig. 1. The much-photographed side of the Vasquez Rocks pinnacle and main film staging area. (Photo: Michael Ramsey.) In fact, the Vasquez Rocks now have the distinction of being an overexposed outdoor location simply because of their proximity to the big city of Los Angeles’ filmmaking industry, hence their presence in scores of films, television programmes and music videos. Only about 64.5km from Los Angeles, the Vasquez Rocks are off State Highway 14, between Acton and Santa Clarita in California, USA and can be seen from Highway 14. The signs will direct the motorist to the exit that leads to the Vasquez Rocks … 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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Geo junkets: New Zealand, North Island (Part 1)

Jesse Garnet White (USA) Fig. 1. Legend/Key:1 = Sediments (Cretaceous and Cenozoic).2 = Greywacke (Permian and Triassic).3 = Schist (Carboniferous to Cretaceous).4 = Volcanic rocks (Cretaceous and Cenozoic).5 = Sediments and ophiolites (Northland and East Coast allochthon) (Cretaceous and Oligocene).6 = Pyroclastic rocks (Triassic and Jurassic).7 = Limestone, clastics and volcanic rocks (Central and Eastern sedimentary zone) (Cambrian to Devonian).8 = Granitoids (Paleozoic and Cretaceous).9 = West Fiordland metamorphic zone (Paleozoic and Cretaceous).10 = Ophiolites and pyroclastics (Permian).11 = Volcanic rocks (including pyroclastics) (Permian).12 = Mafic and ultramafic complexes (Paleozoic and Cretaceous).13 = Greywacke (Western sedimentary zone) (Cambrian to Ordovician). Auckland and the AVF In a thick brain fog, crusty eyed and yawning, I sat up in bed at 4:30 am. I was in Auckland, New Zealand. It was still dark outside when I drove to Mount Eden (Maungawhau), where I hiked up a narrow dirt trail lined by tall grass stippled with dew. Coming out of the verdure, my shoes, socks and shorts were soaked through. On top of the hill, a shadow-black grouping of trees blocked the creeping morning light from behind the Hanua Ranges. The burnt orange sunrise, obstructed by cumulous, lit up like a distant mountain wildfire. Auckland city centre was under puffy, lavender-white cirrus clouds, reflecting pastel colours across the harbour. Alone in the cool and crisp pre-dawn air, I viewed the various scoria cones in the Auckland Volcanic Field (AVF) bursting through the city neighbourhoods. Fig. 2. Map of New Zealand showing place names. … 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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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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Northern Rocks: Shetland

Neville Martin (UK) Shetland is famous for many things including ponies, knitwear, sheep and sheepdogs, birdlife and fishing. It is less well known for being an excellent attraction for the geologist or that it is currently going through the process of qualifying for European and World Geopark recognition. The rocks of Shetland are too old for fossils with the exception of some fish and aquatic plant fossils at the southern and western extremities. However, what it lacks in fossils it more than makes up for in an abundant variety of minerals and geological structures and, while looking for minerals, the geologist can enjoy some of the most spectacular seascape in the UK. In addition, the islands have a long history of mineral extraction and there has been talk of possible, future platinum and gold mining. Fig. 1. Old Red Sandstone Cliffs, Bard Bressay and Noss. One of the reasons for the geological diversity is that the Great Glen Fault, which formed Loch Ness, also manifests itself in Shetland. This gives rise to a displacement of some 60 to 80km, such that there is a distinct difference between East and West Shetland. The landscape is also the result of sculpturing by glaciers and the sea. The many submerged, glacial valleys are called “voes”, the largest of which is Sullom Voe, the site of the oil terminal where oil from north, east and west of Shetland is landed. The shelter provided by such a large voe (which is sea loch) made it … Read More

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Important Green River Formation fossils come to New York

Stuart Wilensky and Douglas Miller (USA) In the early Eocene Epoch, drainage from the newly uplifted Rocky Mountains filled an inter-mountain basin to form what geologists call Fossil Lake. The climate of Fossil Lake was subtropical, similar to the climate of Florida today. The lake persisted for about two million years, and was home to palm trees, turtles, birds and an abundance of fish. On numerous occasions, unique conditions came together to result in some of the best-preserved fossils ever discovered. The sediments of Fossil Lake were first discovered in the 1860s, near the town of Green River Wyoming, and the area was named the “Green River Formation,” which is well-known in the scientific community and by amateur collectors. Palaeontologists have long theorised that the lake was deep enough to be anoxic (devoid of oxygen) at the bottom. This prevented scavengers from disturbing the plants and animals, and inhibited decomposition. Algae, and other plant and animal life, would die and fall to the bottom as in lakes and ponds today. Storms brought runoff from the mountains, covering the flora and fauna with mineral-rich material that would ensure their preservation. Recently, scientists have asserted that a kind of “red tide” may have been responsible for the many perfectly preserved fossils found. (“Red tide” is a common name for algal blooms, which are large concentrations of aquatic microorganisms, such as protozoans and unicellular algae. These can cause a severe decrease oxygen levels in the water column, leading to mass mortality events.) We … Read More

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Urban geology: A failed example of gabions as false urban geology from the Netherlands

Stephen K Donovan (The Netherlands) The provinces of Noord and Zuid Holland, including much of the Dutch North Sea coast and adjacent inland areas, are devoid of rocky exposures. In a region of flat-lying Pleistocene siliciclastic successions (Burck et al, 1956), there are no quarries, cliffs or other man-made or natural exposures of lithified rocks. The topography is slight, with the highest natural structures being the coastal sand dunes, in part preserved as a national park (Jelgersma et al, 1970). To offset this lack of geological ‘furniture’, the Dutch have enterprisingly imported and installed sundry rocks that fill what may be an unattractive void in the environment. These rocks vary from the minimalist, such as roadside boulders (in part, possibly erratics) (Donovan, 2015), to reconstructions of structures such as a replica of a natural bridge in Mississippian limestone slabs (Donovan, 2014). But, in some instances, reconstructions are unsuccessful or, at least, inaccurate, such as the false (Pennsylvanian) Coal Measure strata without identifiable coal beds in the national railway museum (Het Spoorweg Museum) in Utrecht (Donovan, 2018a). In this article, I describe further mock geological structures that fail in the details. Gabions are tools of the engineering geologist. Yet, when packed with cobbles of imported, grey Mississippian limestone, they may make convincing false sedimentary ‘beds’, at least from a distance, and are a not uncommon feature of the environment of Noord and Zuid Holland (Donovan, 2018b). (Vertical, dyke-like structures are rarer and are less successful as false geology; Donovan, research in … 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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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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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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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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Roman quarries in Austria and Germany: A short sight-seeing tour

Dr Robert Sturm (Austria) This is the third of four articles on the quarries of the ancient world and later, and, in particular, the marble that was quarried there and the works of art made from it. The first is Mining in Ancient Greece and Rome and the second is Marble from the Isle of Paros – a tour of the ancient quarries. The ancient methods used An antique quarry is interesting because it is a place where raw material for buildings and sculptural works was extracted to specific sizes and shapes with the technical methods of that time. The mining techniques did not change very much from the earliest phases of human civilization until the end of antiquity, even though the methods used continuously improved over time. In ancient Greece, single blocks of the stone were separated by smashing several key holes into the rock wall, into which wooden wedges were driven. After that, the wedges were moistened, causing their expansion and the cracking of the block along the line of holes. For a better control of the rock fracture, long groves were carved into the blocks with iron tools, into which key holes were subsequently inserted. Alternatively, the blocks were completely split off from the rock walls by deep cuts in the rock and then separated from the ground using crowbars (Fig. 1). Fig. 1. Separation of single blocks of rock using a crowbar and leverage. Since archaic times, rock saws have also been used. In the Roman … Read More

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Fossil fish from northern Scotland

 Bob Davidson (UK) The north of Scotland is famous to scientists and amateur collectors for its wealth of localities where fossil fish of Devonian age can be collected. From plate tectonics, we know that in Devonian times Scotland was situated just below the equator, as part of a continent that was largely arid desert and where land plants were only just emerging. Most life on earth was still aquatic and fishes were the most successful backboned animals. The fossil fish of the area are unique in many ways. They present a window on the development of vertebrates, in which many of the innovations necessary to pave the way for the next great evolutionary step (the invasion by tetrapods of the land) were already in place. The fauna contains the acanthodians, one of the first group of vertebrates to evolve jaws, and the lobe finned fishes, so called because of their fleshy lobes supporting their pectoral and pelvic fins. The lobe fins also include the lungfish. Their fleshy fin lobes played an important role in the development of the limbs of early four-legged animals (tetrapods) and ultimately to all terrestrial vertebrates today – including ourselves. The classic Middle Devonian (380 to 375Ma old) locality is Achanarras Quarry in Caithness, where exquisitely preserved fish can be collected in an old roof tile quarry. Many such quarries existed in the past and fish have been widely collected from several localities over the years. The fish are preserved in thinly laminated siltstones and limestones, … Read More

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What’s so special about South Devon?

Professor John CW Cope (National Museum of Wales, Cardiff UK) Take a trip to the South Devon coast around Easter time and you are bound to come across student parties from universities engaged in fieldwork. What is it about this area that makes it so popular as a centre for this? The simple answer lies in a single word — variety. There is probably no other area in the UK where such a wide variety of rock types and ages is well-exposed in such a small geographical compass. Let’s have a look at some of the factors. The geological succession The oldest rocks exposed in South Devon are of Devonian age and, unlike many other areas of the UK, the Devonian rocks are in marine facies virtually throughout. Looking back over the history of geology, the age of these rocks had initially proved difficult to identify and it was only after Murchison had seen the marine successions in The Rhineland and Russia that he realised that these marine rocks were the equivalent of the Old Red Sandstone farther to the north. The Devonian rocks present a variety of marine facies, with the Middle Devonian limestones being of particular note. The limestones are a local development whose presence, in an otherwise deeper water succession, is due entirely to local shallowing of the water caused by thicknesses of volcanic rocks extruded along extensional fault lines as the local basins developed. This shallowing allowed reef-building organisms to flourish and the principal ones of … Read More

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Discovering dinosaurs in Britain: The significance of the British dinosaur record

Dean R Lomax (UK) Palaeontology and Britain In its simplest form, palaeontology is the study of prehistoric life, through examination of fossils. Palaeontology is, however, not just dinosaurs. Dinosaurs constitute a miniscule portion of what palaeontology is. After all, a myriad of different, and often down-right bizarre, organisms lived long before the dinosaurs and ended up as fossils under their feet. Regardless, the imagination and wonderment that dinosaurs create are why they are considered a symbol for palaeontology – they are a gateway into this most incredible of sciences. The geology and palaeontology in Britain is incredibly diverse. Rocks of almost every geological period are exposed and have been studied for hundreds of years. This provided a platform for geology and palaeontology to flourish and evolve. Some rather notable individuals include the geologist, William Smith – the ‘Father of Geology’. In 1815, Smith created the very first geological map of England, Wales and part of Scotland, a ground-breaking achievement. Incredible fossil discoveries found along the beach at Lyme Regis, by the greatest fossil hunter ever, Mary Anning, paved the way for the first scientific descriptions of large, extinct reptiles – the ichthyosaurs and plesiosaurs. The Rev William Buckland provided the very first scientific description of a dinosaur – this would change the world. Fig. 1. The author pictured with dinosaur footprints at Hanover Point, Brook, Isle of Wight (2014). Our fascination and intrigue in studying and examining the rocks and fossils within has unlocked an ancient, alien world. If you … Read More

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Jurassic Coast (or is it?) with the Geologists’ Association

Mervyn Jones (UK) Since 2012, the Geologists’ Association (GA) has put on annual field trips to the Dorset coast led by Prof John CW Cope (of the National Museum Wales), who is author of the definitive Field Guide No 22. The second edition was published in April 2016 (Geology of the Dorset Coast (2nd ed)). In fact, the trips were started to celebrate the publication of the first edition of the guide. The Dorset Coast is often equated with the ‘Jurassic Coast’ when, in fact, the geology stretches from the topmost Triassic, near the Devon border, through Jurassic and Cretaceous successions, to Eocene deposits at Studland. For this and other reasons, it attracts amateur geologists in large numbers. John’s guide provides essential information including descriptions of the succession and practical guidance about access. What’s missing are the entertaining stories that John Cope can provide and the context provided by exploring inland a bit. Day 1 – Saturday (1 October) For our fifth field meeting, we met up in Lyme Regis (in the car park next to the newly-restored house originally owned by John Fowles – see below) – a town to stir the heart of any geologist. Our mission for the weekend was to look at the unconformity below the Cretaceous, as it oversteps the older Jurassic and Triassic strata progressively in a westerly direction. En route, we observed the instability of the cliffs and suffered the same ourselves, as we scrambled over the boulders and shingle. On this occasion, … Read More

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Humble flint sea urchins and the stories they tell

Joe Shimmin (UK) Flint is a very hard-wearing rock from the chalk of the Upper Cretaceous. Whole beaches made of flint pebbles can be found many miles away from the chalk strata that the nodules originated in, owing to the rock’s ability to withstand the processes that destroy other rocks quickly. Flint sea urchins are especially hard-wearing, as their rounded shapes require a lot of force to damage, while less-rounded flints tend to break up over time if subjected to high-energy environments, such as beaches and fast-flowing rivers. Because of this robustness, it is possible to find flint urchins, which have undergone some very interesting journeys before being collected, adding to their interest for fossil hunters. Fig. 1. The hardness of flint and the rounded shape of flint urchins make them extremely robust fossils. All flints start off within chalk strata. Where these strata are exposed at the coast or in quarries and cuttings, it is possible to collect flint sea urchins, which, at first, look very much as if they are preserved like every other urchin found in chalk. They have a white calcite-replaced test and all that can be seen of the flint within is a slight blueish tint or maybe a glimpse of the nodule through the anal or oral apertures. Of course, flints can also be found that partially or fully envelop an urchin and, in these cases, highly aesthetic display pieces can sometimes occur. Fig. 2. Two of these pristine fossil urchins, extracted straight from … 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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Giant trilobites and biotite nodules in Portugal

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

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