Meteorites: ‘rocks’ from space

Dr Vic Pearson (UK) Every year, thousands of tonnes of dust and rock penetrate the Earth’s atmosphere. The fiery passage of these objects produces the familiar ‘shooting star’ phenomenon, known as meteors. Much is destroyed during this descent, but some material is delivered to the Earth’s surface, either as meteorites or micrometeorites (the latter being typically less than 1mm). However, only 1% of the surviving material is large enough for identification and recovery, making meteorites and micrometeorites much sought after, both scientifically and commercially. Fig. 1. Meteors, or shooting stars, are a regular sight in our skies. Not all survive atmospheric entry but produce spectacular fireballs. (Image courtesy of A. Danielson.) Naturally, bombardment by extraterrestrial materials has been ongoing throughout Earth’s history. The early Solar System would have been a turbulent time and the young Earth was subject to much greater amounts of extraterrestrial infall than today. Our geological record contains many impact craters, and fossilised meteorites have been found in Ordovician sediments in Sweden (Schmitz et al., 2001), thought to be the result of the catastrophic break-up of an asteroid 470 million years ago. Today, it is accepted that the majority of meteorites are fragments of asteroids broken off during collisions with other extraterrestrial objects, perturbed from their orbits by the gravitational effects of Jupiter. The origins of micrometeorites are less well constrained and evidence abounds for both cometary and asteroidal origins. Types of meteorites Meteorites are generally classified as either falls or finds. Falls are those that are … Read More

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The disparids: Weird and weedy crinoids of the Palaeozoic

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

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Geology museums of Britain: Kendal Museum of Natural History and Archaeology, Cumbria

Jon Trevelyan (UK) Kendal Museum is one of those charming, cluttered museums I feared were dying out (Fig. 1), but still seem to defy the odds and continuing surprising visitors. Like the museum in Whitby (see Geology museums of Britain: Whitby Museum, Yorkshire), at Kendal, there seems to be exhibits stuffed anywhere possible, with surprises everywhere you look. The museum itself is a local museum in Cumbria, on the edge of the Lake District in northwest England. It was founded in 1796 and includes collections of local archaeology, history, geology and natural history from around the globe, but especially from the Lake District itself. Fig. 1. A model boat and bicycle – typical of the eclectic displays. In April 2011, Kendal Museum achieved the Visitor Attraction Quality Assurance Scheme assessment, awarded by Visit England. It is managed by Kendal College on behalf of South Lakeland District Council and is part of the Arts and Media campus at the North End of Kendal. History The Museum of Natural History and Archaeology is one of the oldest museums in the UK, with displays of local and global natural history, and archaeology. Kendal’s first museum was founded in 1796 by William Todhunter, who exhibited a collection of fossils, minerals, plants, animals and antiques. In 1835, the Kendal Literary and Scientific Society took over the museum and, as the collection grew, the museum had to be rehoused several times. In 1913, the current building was offered to the Town Council to house the museum. … Read More

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Oxygen-free storage for pyrite speciments

Dr Caroline Buttler (UK) Oxygen is responsible for the majority of chemical reactions that lead to the decay and degradation of museum specimens; the corrosion of iron and the fading of many pigments when exposed to ultraviolet light could not occur without the presence of oxygen. It is also essential for the life forms responsible for biological decay such as insects, fungi and bacteria. The most common oxidation reaction affecting geological specimens is pyrite decay, which damages specimens containing pyrite or marcasite.  Pyrite decay occurs when the sulphide component in these minerals oxidises to form ferrous sulphate and sulphur dioxide, and can result in the complete destruction of the specimen and the associated labels and packaging materials. If pyrite specimens can be stored without oxygen then deterioration could be prevented. Fig. 1. Ammonite specimen with pyrite decay (©National Museum of Wales). The technology to produce oxygen-free environments to museum standards has burgeoned in the last few years. Nitrogen and other inert gases such as argon and helium have been successfully used to display specimens without oxygen, but it is costly and only used for rare or valuable objects. For example the American Charters of Freedom, which include the Declaration of Independence, the Constitution and the Bill of Rights, in the Rotunda of the National Archives Building in Washington, DC, are displayed in cases inside which an anoxic environment has been created containing a humidified argon atmosphere at 19°C. Anoxic storage can also now be achieved relatively cheaply and efficiently with … Read More

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Gigantic rhizodonts in Scotland’s lochs: The one that got away

James O’Donoghue (UK) Fig. 1. If gigantic rhizodonts still lurked in Scotland’s lochs, anglers might find they are biting off more than they can chew. (Illustration by Megan Whatley.) Every angler dreams of reeling in a prize catch – a 40lb pike perhaps, or a whopper of a salmon. Record-breaking fish fire the imagination as few other creatures can, and the lochs of Scotland have inspired many a fishy tale. However, even the tallest of these stories pale into insignificance when compared with the primeval occupants of the lochs. Had you cast a line there 340 million year ago, you could have ended up as bait yourself. For Scotland’s ancient lakes and rivers held a behemoth of a fish known as Rhizodus hibberti (Fig. 2), which notched up a truly staggering snout-to-tail length of seven metres. It was the ultimate ‘one that got away’, a predator that was half as big again as a great white shark. To this day, it remains the largest freshwater fish ever to have lived. Rhizodonts, the group of fishes to which R. hibberti belonged, may have been the last truly gigantic predators to live in fresh water, suggests palaeontologist Jon Jeffery, an expert on one of the most widely distributed species, Strepsodus. They also have the distinction of being the most primitive ‘tetrapodomorphs’ known. That is, they belong to the group of fishes from which tetrapods descended. Tetrapods are vertebrates that colonised land and includes all amphibians, reptiles, birds and mammals. Fig. 2. Jaw … Read More

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

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

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

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

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Book review: Essex Rock – Geology beneath the Landscape by Ian Mercer and Ros Mercer

To be fair, Essex has never been famed or well-regarded for its geology, at least not by me. I know it has its locations – Walton-on-the-Naze springs to mind – but not a lot else. However, this guide is set to change all that. Full colour photographs and illustrations (on virtually every page), with 416 pages of excellent text, with particularly good sections on the London Clay and Red Crag, it is as good as it gets. It is worth owning for its own sake, even if you are not going to, or are living in, Essex.

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

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

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Yana’s rock formations in India

Khursheed Dinshaw (India) “Let’s organize a hike to Yana to see its impressive rock formations,” suggested Ramesh V, the wellness consultant at Gamyam Retreat, which is a luxury wellness resort located an hour’s drive from Yana. My interest piqued. The next day, I headed to Yana located in Uttara Kannada district in the state of Karnatake in India. The area is surrounded by the thick forests of the Western Ghats. Fig. 1. Mohini Shikhara is 300 feet (91.5m) in height. After parking the vehicle, my hike began through the forest along the demarcated trail for hikers. Hardly a few minutes had passed before I was rewarded by the spectacular view of a sharp-edged peak. It was made up of hard and compact siliceous limestone of Late Archean age, that is, around 2.65 billion years old. Known as Mohini Shikhara (Fig. 1), this imposing rock sentinel is 300 feet (91.5m) in height. Fig. 2. A rock formation of the Late Archean age. After admiring it for a while, I continued ahead and spotted other rock formations along the way (Figs. 2, 3 and 4). Fig. 3. A rock formation surrounded by the thick forests of the Western Ghats. By this time, the trail had turned into a series of steps with railings for support. I enjoyed the solitude of the forest, the cascading streams and the bird calls everywhere along the way. And there are close to 60 rock formations at Yana, which are scattered throughout the forest. From among those … Read More

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Ice, dykes and tectonics: the Plattsburgh story

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

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Geology museums of Britain: The Hunterian, Glasgow

Jon Trevelyan (UK) This is the second of my articles on the geology museums of Glasgow (see also Geology museums of Britain: Kelvingrove Art Gallery and Museum, Glasgow). The Hunterian contains for some Scotland’s finest collections, covering subjects such as Roman artefacts from the Antonine Wall (fascinating, given that its big, southern, brother – Hadrian’s Wall – gets all the attention), and scientific instruments used by eminent Scottish scientists, James Watt, Joseph Lister and Lord Kelvin. In fact, the Hunterian’s whole collection is ‘Recognised’ as nationally significant in Scotland. It is also home to one of the most distinguished public art collections in Scotland. However, as always, it was the geology and palaeontology that I went to visit (Fig. 1). Fig. 1. The hall of the museum, with the geology and palaeontology exhibits set out below. The Hunterian’s founding collection came through the bequest of the eponymous Dr William Hunter (1718-1783). The museum itself opened in 1807, and a catalogue was published in 1813 (Fig. 2) by Captain John Laskey, who took visitors through the museum room by room and case by case, describing the items on display. Fig. 2. The catalogue of the original museum contents, by Captain John Laskey, with a lovely shark’s tooth from the original collection. And, apparently, the fossil collections are among the largest in the UK and were built up over the last 200 years from departmental research and teaching collections. Fig. 3. Ripple marks covered in trace fossils. Fig. 4. Copious fossils on … Read More

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Geology museums of Britain: Kelvingrove Art Gallery and Museum, Glasgow

Jon Trevelyan (UK) When I went up to Glasgow to attend my son’s graduation, I deliberately made some time to visit Kelvingrove Art Gallery and Museum to explore its 22 galleries. These cover everything from art to animals, Ancient Egypt to Charles Rennie Mackintosh and much, much more besides. However, the reason why I am including Kelvingrove in my series covering the geology museums of Britain, and the real reason for my visit, is its gorgeous collection of fossils, in particular, significant ones found from Scotland and, indeed, in and around Glasgow. Located in the beautiful Kelvingrove Park (Fig. 1), the art gallery and museum opened in 1901 and is clearly a firm favourite with local people and visitors. It has stunning architecture (Fig. 2) and a family friendly atmosphere; and has relatively recently been redesigned – without losing its Victorian traditions and ideals – so that it is upgraded for the twenty-first century. Fig. 1. The museum is located in Kelvingrove Park, which necessitates a lovely walk through the grounds of this Victorian, public park. Fig. 2. The magnificent frontage of Kelvingrove Art Gallery and Museum. In fact, Kelvingrove started life as typical Victorian museum (Fig. 3), founded by (as the guide puts it): … the wealthy classes to assert their cultural worth and improve the people of the city”. Fig. 3. The roof of the Victorian entrance hall. However, as I say, there have been improvements, which were achieved by asking Glasgow residents what they approved of the … Read More

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Sharks of the Moroccan phosphates

Dr Charlie Underwood (UK) Shark teeth are amongst the most iconic and sought after of fossils. However, for most of us, collecting them can be a difficult or even unpleasant task. I am sure that most collectors in northern Europe are familiar with picking their way over slipped cliffs of clay, in the teeth of a freezing winter gale, to collect the few treasures that erosion leaves on the beach. Alternatively, the more dedicated are used to carrying hundreds of kilos of clay home and painstakingly passing it through a sieve before even knowing if there are any fossils there. But it is not all like this. There are a number of places in the world where the vagaries of sedimentology have allowed bone-beds (or phosphorites) to develop, within which vertebrate fossils, and shark teeth in particular, are hundreds of times more abundant than in a normal marine sediment. By far the most extensive of these deposits are in Morocco. Below the dusty scrub and parched farmland of northern Morocco lie the largest reserves of mineral phosphate known. Vast complexes of open-cast mines, one stretching for nearly 30km, have been cut into these deposits, with a network of conveyor belts transporting the phosphate sand and rock to the processing factories turning the rock into fertilizer. These great phosphate deposits were laid down in a sea saturated with nutrients and teeming with life. As a result, the phosphates are crammed with the fossilised phosphatic bones and teeth of fish, sharks and … Read More

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Geology museums of Britain: Yorkshire Natural History Museum, Sheffield

Jon Trevelyan (UK) Fig. 1. The museum’s logo. To no little fanfare, this new museum of natural history (and, in particular, fossils) opened on 13 August 2022. James Hogg, who is Chairman at the Yorkshire Natural History Museum (Fig. 2), only had the idea for it earlier this year. Fig. 2. The museum from the outside. James (Fig. 3) true passion for palaeontology came when he was a student. His background is one an economist (in particular, the economic history of institutions and economic growth). However, his idea for the museum is based on his interest in growing a public institution so as many can benefit as possible in the long-run. Fig. 3. James Hogg, with the skull of a huge ichthyosaur. After the idea of the museum took shape, James quickly renovated what was a badly dilapidated property (Figs. 4 and 5) to make it happen. Fig. 4. The inside of the building earlier this year. Fig. 5. The refurbishments have had to be extensive. Now finished, the museum’s exhibits include fossils that have been found along the Yorkshire coast from the Jurassic period, from ammonites to belemnites to those huge behemoths, such as ichthyosaurs, that once hunted in the Jurassic oceans. However, not only is the museum a store for natural history specimens, it will also actively research the collection and will provide visiting academics free access to it. That is, the stated purpose of the museum is to create a dedicated natural history museum in the north … Read More

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Fossils down under or finding fossils in boreholes

Dr Susan Parfrey (Australia) You may be familiar with collecting fossils from eroded rock surfaces, a riverbank, a road or rail cutting, a cliff face or a fresh cut surface such as a quarry. But there is another way fossils can be recovered – from boreholes. Boreholes have been drilled in Queensland for many years for exploration and to investigate the regional geology. Since Queensland is a relatively flat part of Australia, outcrops can be hard for geologists to find. Therefore, drilling offers a way of studying sub-surface geology that assists in the understanding of the stratigraphy of the State. Usually, drilling does not produce usable macrofossils. The process of drilling normally involves pushing a mud mixture down the borehole and over the bit, for cooling and lubrication. In this process, larger fossils are forced to the surface in the drilling mud and are broken into small pieces making them impossible to identify. However, microfossils can be recovered, as they are so small they are undamaged by the drilling process and are recovered at the surface to be identified and used in biostratigraphy (to date and correlate rocks). However, in Queensland, drilling was undertaken by the Geological Survey that retrieved lengths of core which provided access to deeply-buried strata and allowed recovery of both micro and macrofossils. Exploration companies also often retrieved short lengths of core at specific levels of interest, which sometimes contain fossils. Before a borehole is drilled, considerable geological mapping of the surface is undertaken. Only then … Read More

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The dinosaurs of the Isle of Wight

Simon Clabby (UK) There has been much written about the dinosaurs of the Isle of Wight over the years. For example, Gideon Mantell, who discovered Iguanodon in 1821, wrote a book on the geology in 1847, in which he refers to its fossil fauna. However, like all sciences, palaeontological research does not stand still. Every year, our knowledge about dinosaurs changes as new discoveries are made. This is true even of the Isle of Wight, which, since the 1980s, has experienced a sudden upsurge in research, making many books on the subject now out of date. The first dinosaur discoveries took place in antiquity, with local stories of “stone horses” (presumably Iguanodon, due to its horse-like skull) being found in the cliffs. However, the first scientific discoveries took place in 1829, when William Buckland (describer of Megalosaurus) described some Iguanodon material from Yaverland. The mid 1800s was a time of massive interest in dinosaur research, with the Rev. William Fox, curate at Brighstone village (not far from the fossil-rich cliffs at Brighstone bay) apparently neglecting his duties to look for fossils. In fact, he managed to discover four new species during his tenure at Brighstone. Fig. 1. Brighstone Bay. There was a bit of a lull in the early twentieth century, with nothing new being discovered until the 1970s. However, since then, at least three new species have been described, and a further seven previously known species being reassigned to new taxa. The dinosaurs of the Isle of Wight almost … Read More

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The violent story of Cumbria’s ancient volcanoes

Ian Francis and Bruce Yardley (UK) The violent eruption that occurred near the Pacific island of Tonga in January 2022 reminded the world of the ferocious power of volcanoes. The most destructive eruptions can bury huge areas in layers of ash and lava, generate tsunamis, and even alter the Earth’s climate by injecting vast quantities of ash and aerosol droplets high into the atmosphere. Modern Britain is luckily far from any active volcanoes (Vesuvius in Italy, and the volcanoes of Iceland are the nearest to us), but this was not always the case: geological evidence shows that around 455 million years ago, during the Ordovician Period,an intense, but short-lived, periodof volcanic activity took place inwhat is now the Lake District. The geological record of that activity is mainly found in Lakeland’s high and rugged central fells, stretching from Ennerdale and Wasdale in the west, across to Haweswater in the east. Most of the Lake District’s highest fells are found in this central belt, including the Coniston fells, Pillar, Great Gable, Kirk Fell, the Sca Fells, Esk Pike, Crinkle Crags, the Langdales, Helvellyn and High Street (Fig. 1). Fig. 1. Volcanic rocks form the high central fells of the Lake District. The image shows banded volcanic ash beds (tuffs) on the flank of Glaramara, looking east over Heron Crag (in shadow), Ullscarf, and beyond the Helvellyn range. (Photo: Stuart Holmes.) As far back as the early nineteenth century, those familiar with the rocks and landscape of the Lake District (such as … Read More

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The mud volcanoes of Azerbaijan

Khursheed Dinshaw (India) The first time I saw a mud volcano at close range was in Rotorua in New Zealand. I was fascinated – the raw energy of the erupting mud massively appealed to me. Once back home, I read up on mud volcanoes and learnt that, out of the almost 700 present in the world, about 300 of which are located in Azerbaijan and the Caspian Sea. No wonder scientists call Azerbaijan ‘the region of mud volcanoes (Fig. 1). These mud volcanoes reach heights of 200 to 500m and temperatures of 1,000 to 1,2000C. They include active and extinct underwater, island-type and oil producing volcanoes. In Azerbaijan, one can find these natural wonders on the Absheron Peninsula, at Gobustan and the Shirvan plain. Fig. 1. A map of the mud volcanoes of Azerbaijan (© Mark Tingay and Google Earth). Recently, I was fortunate enough to visit the country and booked a tour to Gobustan to experience the famed mud volcanoes, which are locally known as ‘Pilpila’ (Fig. 2). One can drive up to the designated spot in any vehicle, but the last few kilometres necessary to reach the volcanoes is only possible by authorised cars driven by locals who know the landscape like the back of their hand. This is important, because the terrain is barren and there are no marked roads, routes or signposts to get to the mud volcanoes. Fig. 2. Mud volcanoes are called Pilpila in Ajerbaijan. My driver was born and brought up in a … Read More

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Stones that illustrate themselves

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

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

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

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Meteorites and tektites

David Bryant (UK) The Solar System formed around five billion years ago from a cloud of dust and debris orbiting the Sun. By a process of accretion and remelting by electrical discharges within the dust cloud, this material condensed into spherical particles called chondrules. By collision, the chondrules fused together to form larger and larger planetesimals and these aggregated to form asteroids and the planets themselves. All the rocky planets (that is, Mercury, Venus, Earth and Mars), together with many of their satellites, show evidence of the collisions that formed them. Debris from the original formation of the Solar System is still abundant. Many tonnes fall onto the Earth every year as meteorites – perhaps as much as 300 tonnes each day. These can be broadly classified into the three types discussed below. (1) Stony meteorites (a) Chondrites are debris from the original condensation of the Solar System and are undifferentiated. That is, the various elements of the original solar cloud are all present. For this reason, they are attracted to a magnet because of the nickel-iron they contain (within more massive bodies, like asteroids and planets, the heavy elements migrated inwards to form a core). Chondrites are classified using an alphanumeric system that refers to the abundance and size of their chondrules (on a scale of 3 to 6, with 3 meaning there are abundant chondrules present and 6 meaning there are indistinct or sparse chondrules) and their iron content (referred to as either ‘L’ for low or ‘H’ … Read More

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The fossil forest of Curio Bay

Heather Wilson (New Zealand) Fig. 1. The location of Curio Bay. The 180 million year old fossilised forest at New Zealand’s Curio Bay is of international geological significance. When I visited the area recently, the wind was blowing a gale and there were high seas. There is a two-minute walk from the car park to a lookout and then a series of steps down to the beach. When the rocks and fossilised trees are wet, they are slippery, so you need good footwear. This is a protected area. When I visited, there was a representative from the Department of Conservation guarding the beach. There are also video cameras keeping an eye on the fossilised forest, making sure it doesn’t gradually vanish as a result of tourists and rock hounds making off with specimens. Fig. 2. View of Curio Bay. This is one of the most extensive and least disturbed examples of a Jurassic fossil forest in the world. The area within which it is found stretches for about 20km, from Curio Bay, south-west to Slope Point. When the forest was living (during the Middle Jurassic epoch), New Zealand was part of the eastern margin of the ancient super-continent known as Gondwana. North of Curio Bay, most of the country’s future land area was beneath the sea. The fossilised trees occur in green sandstones, alternating with blue shaley clays containing plant impressions. Silica has entirely replaced the woody structure of the trees and rendered them extremely resistant to erosion. Therefore, they … Read More

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The Spittles Landslip, Lyme Regis

Richard Edmonds (UK) On the evening of 6 May 2008, a 300m section of the cliffs east of Lyme slid towards the sea creating one of the most spectacular landslides in recent years. Members of the local fire brigade were training along Gun Cliff, the easterly promenade of the town, and they, along with local residents, witnessed the event. Apparently, a flock of seagulls were suddenly spooked into flight amid much squawking, which drew people’s attention to what was happening. A huge block of dark, Lower Jurassic shale was sliding over the sea cliff and onto the beach accompanied by a deep rumbling noise and, shortly after, a strong smell of sulphur. Luckily, it was high tide and no one was on the beach at the time. I suspect that if anyone had been, they would have seen numerous small falls, cracks and movements taking place before the main failure and would have had time to get away. However, the risk to the public was obvious and the Lyme Regis coastguard team were called as dusk descended. Fig. 1. An ariel view of the Spittles Landslip from the Maritime Coastguard Agency helicopter. Maritime ©Coastguard Agency/Dorset County Council. The following morning revealed the extent of the landslide, especially from the air. There are a few perks in my job with the County Council and as a member of the local coastguard rescue team, but someone had to go up in the new Maritime Coastguard Agency helicopter and I was picked as … Read More

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Fossil from Denmark (part 2)

Niels Laurids Viby (Denmark) The first half of the Palaeocene in Northern Europe belongs, more or less, to the Danish! On 16 November 1846, Edouard Desor held a lecture in Paris with the title ‘Sur l’étage Danien, nouvel étage de la crai’ (‘On the Danien, a new stage of the Cretaceous’) – the Danien was, at that time, seen as being the final stage of the Cretaceous period. Nowadays, in most parts of the world, including most of Europe, ‘Danien’ is the recognised name for the geological age stretching from the end of the Cretaceous (somewhere between 64 and 65mya, depending on what book you read) to some five million years later. Danien deposits are widespread in Denmark, apart from in the southern part of Jutland, and even here you can find flint and blocks of chalk from hardened Danien beds on every stony beach. For fossil collectors from countries that do not have these sediments, Denmark is a good place to visit – it is virtually impossible to come home without at least some Danien fossils, although probably not a great variety unless you visit Fakse Chalk Quarry (which is discussed below). Danien chalk – a lot of different sediments: Stevns Klint The layout of the Danien is best seen at Stevns Klint on Zealand, which has some 20km of cliffs, averaging 20m in height. Fig. 1. Stevns Klint – southern end. Here, the bottoms of the cliffs are, in most places, Cretaceous, being from the very top of … Read More

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From sea to sand – ancient marine reptiles from the deserts of Saudi Arabia

Benjamin Kear (Australia) The hot, dry deserts of modern Saudi Arabia are not renowned as a source of ancient marine reptile fossils. Indeed, only a few years ago, virtually nothing was known beyond a few unidentified scraps of bone recovered by petroleum geologists searching for oil. However, recent exploration by teams of both Saudi and international palaeontologists have led to some exciting new finds that are helping to piece together the 190 million year long story of marine reptile evolution in the Arabian Peninsula. Fig. 1. A map of the modern Arabian Peninsula (with Saudi Arabian borders) showing the extent of the Arabian Shield (lilac) and successive Mesozoic-Cainozoic sedimentary rock exposures: Late Permian to Triassic (violet); Jurassic (blue); Cretaceous (green); Cainozoic (brown). What are marine reptiles? The term ‘marine reptile’ is actually rather ambiguous and does not refer to a specific group. Rather, it applies to any wholly or partly aquatic reptile that makes, or has made, its home in the ocean. Examples of modern marine reptiles include sea turtles (chelonioids), sea snakes (related to terrestrial venomous snakes or elapids), the marine iguana (Amblyrhynchus cristatus) and the salt-water crocodile (Crocodylus porosus). The latter is typically estuarine, but commonly ventures into coastal marine areas. However, the zenith of marine reptile diversity occurred during the Mesozoic or ‘Age of Dinosaurs’, when in excess of ten major radiations, including representatives of those living today (that is, turtles, snakes, lizards and crocodiles), made the transition to life in the sea. Despite having quite different … Read More

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Fenestella and other bryozoans in the Carboniferous rocks of the British Isles

Paul D Taylor (UK) Ask a geologist to name a fossil bryozoan found in the rocks of the British Isles and the most likely answer will be Fenestella. The net-like fossils of Fenestella are especially abundant in the Carboniferous Limestone (Figs 1 and 2), although the genus, as used in its broadest sense, is also present in the Silurian, Devonian and Permian deposits of Britain. Fig. 1. Colony of Fenestella (s.l.) nodulosa from the Lower Carboniferous of Calcot Quarry, Halkyn Mountain, Flintshire. Branches forming the characteristic meshwork fan outwards from the colony origin. Fig. 2. Large colony of Fenestella (s.l.) flabellata from the Carboniferous Limestone of Fife in Scotland. Fracturing of the meshwork is evident. While Fenestella dominates almost all bryozoan assemblages found in the British Carboniferous, a variety of other bryozoans are commonly found. Some Carboniferous bryozoans inhabited reefs or mounds, others were components of non-reef marine communities where they lived together with brachiopods, crinoids and corals at a time when the British Isles was situated close to the equator. All Carboniferous bryozoans constructed immobile colonies consisting of numerous individual zooids, with crowns of tentacles used to capture tiny planktonic algae floating in the water around. Our knowledge of the diversity of Carboniferous bryozoans in the British Isles has increased enormously during the last 50 years through the studies of David E Owen, Ron Tavener-Smith, Adrian J Bancroft and Patrick N Wyse Jackson. Yet, and in common with bryozoans from other geological periods, Carboniferous bryozoans are too often perceived … Read More

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Drought in South Australia creates soil problems

Dr Paul Shand (Australia) In South Australia, the staff of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Land and Water have recently shown that the River Murray, adjacent wetlands and the Lower Lakes (Alexandrina and Albert) close to the Murray Mouth are being seriously impacted by a combination of low water levels and the presence of acid sulfate soils (ASS). The Lower Lakes and the floodplains below lock 1 at Blanchetown are undergoing their first drought since the introduction of barrages more than 50 years ago. Lakes, such as Lake Bonney and Lake Yatco, as well as several wetlands formed by the River Murray, are being isolated as one option to generate water savings and help mitigate drought-related problems in the Murray-Darling Basin. Field observations and chemical analysis confirm the occurrence of both sulphuric materials (pH <4) and sulphidic materials (high sulphide concentrations and pH >4) in a range of ASS subtypes (Fig. 1). Fig. 1. Acid Sulphate Soil with sulfuric material near Swanport adjacent to the Murray River. In addition, some areas contain ‘monosulphidic black ooze’, that causes rapid oxygen depletion of lake and drainage waters when the ooze is mixed with oxygenated waters during disturbance (Fig. 2). Fig. 2. extensive cracking and accumulation of white and yellow Na-Mg-Fe-Al-sulphate-rich minerals or salt efflorescences. Unpleasant smells (‘rotten eggs’), as a result of rotting vegetable matter and the release of gases, have been experienced in these areas of exposed soils when water levels are extremely low or the lakes have … Read More

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Geology Museums of Britain: Portland Museum, Dorset

Jon Trevelyan(UK) Fig. 1. A huge Titanites giganteus adorns the doorway. I visited this little museum a while ago while on a Geologists’ Association field trip. I have passed it several time and always loved the large Titanites giganteus above the door (Fig. 1) of this picturesque cottage (Fig. 2). As a result, I had always wanted to visit, but more particularly I want to see the famous fossil turtle (Fig. 3) that is exhibited there. Fig. 2. One of the two seventeenth century cottages making up the museum. Fig. 3. The lovely fossil turtle at the museum. In fact, Portland Museum is a lovely example of a local museum containing (among other things, geology (Fig. 4), in this case, tucked away in a beautiful part of the ‘island’ in two seventeenth century cottages, near Rufus Castle and the popular Church Ope Cove. Fig. 4. Some of the geological exhibits at the museum. The Isle of Portland in Dorset represents the most southerly point of the Jurassic, which is a UNESCO designated World Heritage Site and famous for its geology, fossils and geomorphology. It is joined to the mainland by the equally famous Chesil Beach but has always been regarded (not least by its inhabitants)as separate from the mainland, and this is reflected in the museum’s collection. That is, Portland Museum does not just contain geology and palaeontology; its exhibits also reflect the Isle’s history and people. Portland Museum was founded in 1930 by Dr Marie Stopes, renowned for her … Read More

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