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Wealden insects: An artist’s impression (Part 1)

Biddy Jarzembowski, Neil Watson and Ed Jarzembowski (UK) Fossil arthropods carry their skeletons on the outsides of their bodies. These exoskeletons may not only be preserved in the fossil record, but also the colour patterns that once adorned them. Therefore, the reconstruction and restoration of the appearance of fossil insects can sometimes be easier and more objective than that of animals that carry their hard parts on the insides of their bodies (such as dinosaurs). In the 1990s, one of us (Neil) undertook the first artistic impressions in pencil and ink of newly-discovered Wealden insect remains from the Early Cretaceous of southern England. A selection of these subsequently appeared in newsletters, books and journals as black-and-white drawings of the whole animal in a life-like pose. Four-colour reproduction is now so widespread, as in this magazine, and more intact fossils have been found, especially in China, that a colour update was needed. However, in this age of computer graphics, Biddy has only used a paint brush and water colours to tint Neil’s images, preserving the original hand-drawn style, and only resorting to Paint software where anatomical details needed changing in the light of new knowledge. Full colour also brought new challenges: decisions had to be made on hues as well as shades. Therefore, Ed has composed some explanatory notes to accompany the pictures. We hope that the first half-dozen results are less artistic licence and more visual models of these ancient life forms. You are, of course, the judge. Fig. 1. … Read More

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Fifteenth century magico-medicinal minerals

Chris Duffin (UK) The Hortus Sanitatis (1491) On 23 June 1491, a new volume was printed and bound for distribution in the German University town of Mainz. The publisher was Jacob von Meydenbach, who might also have been responsible for compiling many of the entries in the book. The volume was based partly on an earlier work entitled Gart der Gesundheit, which was also published in Mainz, but this time by Peter Schöffer, an apprentice of Johannes Gutenberg. This famous pioneer revolutionised mass product printing in the 1450s by developing the use of movable type. Schöffer continued to innovate in this medium after Gutenberg’s death in 1468, experimenting with page sizes, numbers of lines to a column, the arrangement of text blocks and font styles, and the use of woodcuts as illustrations. His Gart der Gesundheit, published in 1483, only a few decades after the inception of the printing revolution, was an immediate success. Meydenbach’s Hortus Sanitatis was prepared as a sort of sequel to the Gart; more ambitious in scope, it was rather longer with additional entries and, importantly for us, a section on stones (Fig. 1). Fig. 1. A double page spread from the De Lapidibus section of Hortus Sanitatis (1491). Wellcome Collection, London.Gart der Gesundheit (German) and Hortus Sanitatis (Latin) both translate as The Garden of Health, giving an indication of the thrust of the volume – here was a treatise on the medicinal virtues of materials from the natural world. The section on stones (De Lapidibus), … Read More

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Pathway to the past: A miner’s photograph

Steven Wade Veatch (USA) Fig. 1, Robert Plews (32), with two daughters, Elizabeth (4) and Mabel (3) and his wife Janet (25), stand in front of their small home in Elkton, Colorado, one of the towns in the Cripple Creek Mining District. (Photo date circa 1899, from the S W Veatch collection.) This photograph, taken around 1899, shows my ancestors posing at their modest frame home, where they lived one step away from Cripple Creek’s gold rush world of cardplayers, whisky drinkers, and midnight carousers. The scene depicts my great-grandfather (Robert Pickering Plews), my great-grandmother (Janet Plews), and two of their daughters in front of their miner’s cabin, built from pine boards, on a hillside in the newly established mining town of Elkton, Colorado. My great-grandparents were from England. Two years after my great-grandfather married my great-grandmother, he left England – by himself – to build a better life in Cripple Creek’s goldfields for the family that he left behind. Robert Plews was a hope-chaser. He carried his dreams from England across the Atlantic and then 1,700 miles to the Front Range and Cripple Creek. He arrived in the gold mining district in 1897. Victoria was the Queen of England, William McKinley was the US President, and Marconi had sent his first wireless transmission. The Colorado Rockies meant a new chance for him at a place with unlimited opportunities. He went to work at the busy Elkton mine. After my great-grandfather established himself in the mining camp, he sent for … Read More

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Book review: Geomodels in Engineering Geology: An Introduction, by Peter Fookes, Geoff Pettifer and Tony Waltham

As this book explains, ground conditions for building depend on the history of all these aspects in connection with both the actual building site and the surrounding area. In fact, the book goes into some detail, using colour photographs and block geomodels, to bring the subject to life in what is, I suspect, a somewhat fresh way.

Geoarchitecture of some Romanesque churches in Aquitaine, France

Nouvelle-Aquitaine (New Aquitaine) is a vast region of southwest France covering more than 30,000 square miles. Between 1154 and the end of the Hundred Years War in 1453, much of the region was under British control. Links with Britain are still strong today, both through tourism and the large ex-patriate British population, particularly in the Dordogne, known jokingly to locals as ‘Dordogneshire’.

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Artist unknown: The dilemma of the Nottoway Stone Image

About 61 years ago, a boy wandered among loblolly pines near an agricultural field not far from the Nottoway River in southern Virginia in the USA. His eyes fell upon a tan coloured rock atop a thick layer of old needles at the bases of the pines. It was a curiosity – the coastal plain Southampton County does not feature rocks reposing at the surface. Young Lloyd Bryant turned over the rounded chunk of stone and was jolted to see an etched human face staring back (Fig. 1).

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Take me to the rocks

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

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From pencils to programming and graphene: Graphite’s role in the transmission of knowledge

Adam Blaxhall (UK) Once a mystery substance thought to be a type of lead, graphite is now one of the most vital components in the ever-expanding world of complex electronics. But this ‘mineral of extremes’ is more than just the familiar grey material we find in pencils. Rather, it is a specific form of the element, carbon (another is diamond) and, from writing products to electrical circuitry, graphite plays an increasingly important role in how we process, communicate and transfer information – and there’s still much to learn from its untapped potential. Graphite: the only mineral for the job A popular misconception is that lead pencils are made from lead (Fig. 1). Fig. 1. Putting lead in your pencil? Graphite was originally considered to be a form of lead and went by the name ‘plumbago’. In fact, they never have been. Graphite – mistaken for a form of lead – has been the main ingredient in the pencil since the largest, purest deposit of the mineral ever discovered was unearthed in Borrowdale in Cumbria, UK in the 1500s (Fig. 2). Fig. 2. Graphite. Graphite is ideal for pencils because its giant structure of carbon atoms – formed of honeycomb-like layers stacked on top of each other – is such that the bonds between atoms are stronger than the bonds between layers. It’s this physical property that gives graphite its soft and slippy texture, and allows the layers to slide off one another. So, when a pencil moves across a surface, … 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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Geology in Leonardo’s ‘Virgin of the Rocks’

Steven Wade Veatch (USA) Leonardo da Vinci (1452-1519), considered one of the greatest painters of all time, used his knowledge of geology to inform his art. Leonardo was also noted for his work in sculpture, anatomy, mathematics, architecture, and engineering during the Italian Renaissance (about 1330 to 1450). From a geological perspective, Leonardo da Vinci’s paintings present a realistic portrayal of nature. In his Virgin of the Rocks (1483-1486), on display in the Louvre in Paris (Fig. 1), the geological accuracy is striking (Pizzorusso, 1996). The painting’s subject is both the Virgin and the rocks. The Virgin sits in front of a grotto or cave, various aspects of which, according to geologist Ann Pizzorusso (1996): … are rendered with astounding geological accuracy. Leonardo has painted a rich earthscape of rock eroded and sculpted by the active geological forces of wind and water. Most of the rock formations … are weathered sandstone, a sedimentary rock”. Fig. 1. Leonardo da Vinci’s Virgin of the Rocks (1483-1486). From his studies of geology, Leonardo learned how the Earth works and improved the realism of his paintings. Location: Louvre, Paris. Oil on panel transferred to canvas. Height: 199cm. Width: 122cm. (The image is in the public domain.) What looks like basalt, an extrusive igneous rock formed by the cooling of lava, appears above Mary’s head and at the top right of the picture. Leonardo even painted the columnar joints formed by the cooling of the rocks. Also, just above her head is a precisely painted … Read More

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Making of a monster: ‘Cannibal the Animal’

Mats E Eriksson (Sweden) A hellish monstrosity of an animal – like a beastly entity taken straight out of your worst nightmare – has come to sculptural life. And it has Death Metal, primordial life and Alex Webster written all over it. Fig. 1. The monster sculpture in progress, with its ‘daddy’ model maker Esben Horn, who also functions as a scale (Esben Horn is 1.85m tall). At this stage, the worm’s body has been roughly sculptured out of Styrofoam and, alongside, the huge jaws still await several adjustments. (Photo: Mats E Eriksson.) Last year, a new gigantic fossil polychaete worm – Websteroprion armstrongi – was discovered and unveiled to the world (Eriksson et al. 2017). (I discuss this in my article: Worm monstrosity: A giant extinct worm.) The creature is an ancestor to the now-living, marine ‘Bobbit’ worms – ambush predators that hunt in stealth mode for octopuses and fish. The fossil species was discovered in 400 million years old rocks from the Devonian Period in Canada and was named in honour of mighty bass giant, Alex Webster, of Cannibal Corpse, Blotted Science and Conquering Dystopia. Now, this primordial animal has come to ‘life’ by the skilled hands of prehistoric sculpture artist extraordinaire Esben Horn, at his company 10 Tons (see Eriksson, 2014) in Copenhagen, Denmark, and assisted by me, who was lead author of the scientific study presenting the species. Since I reported on the discovery of W. armstrongi in Issue 50 of Deposits (Worm monstrosity – a … 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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Wealden insects: An artist’s update (Part 4)

Biddy and Ed Jarzembowski (UK) An ‘artist’s impression’ of Wealden insects, inspired by the original work of Neil Watson, appeared in a three-part mini-series in Deposits issues 47 to 49. Since then, the discovery of a number of species new to science (belonging to diverse groups) has meant that an update was needed. Here are some completely new watercolours by Biddy, including the first true bug (heteropteran) from the Wealden, and the first Wealden earwig (dermapteran). Insects are arthropods and an accompanying Wealden crustacean is added this time. Photographs of actual fossils found in the Weald Clay Formation of Lower Cretaceous (Hauterivian and Barremian) age are provided too. We are indebted to Fred Clouter, Terry Keenan, Tony Mitchell and Pete Austen (UK) for help with these images. As before, Ed has supplied some explanatory notes to accompany the pictures, with more on the way. We have incorporated some new ideas on established species, such as different interpretations of the fossil lifestyle in the case of the ‘moss’ bug. Wealden insects are often disarticulated (due to transport in water). Where intact relatives are known from other contemporary deposits (especially Asia and Spain), these have been referred to, as well as recent representatives. While we can now recognise the commoner insect groups from the late age of the dinosaurs, continuing fieldwork shows that others remain to be unearthed. The artist’s job is ongoing, like that of the specialist and collector. We shall continue to periodically share the finds with you as a … Read More

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Urban geology: The Boxtel wall game

Stephen K Donovan (The Netherlands) The Netherlands is a land of museums, approximately 1,200 of them in a country the size of southeast England. Although the major cities have an ample supply – about 30 in Amsterdam, for example – there are many and varied museums dotted throughout the country. (I remember, in 2003, being driven to Arnhem and seeing a German Panther tank parked outside a small military museum – be ready for the unexpected.) For the geologist, one of the gems is Het Oertijdmuseum (= The Prehistoric Times Museum; formerly De Groene Poort) in Boxtel, in the province of Noord Brabant, north-north-west of Eindhoven. As may be deduced from Fig. 1, the museum has a specialist collection of dinosaurs and other saurian – replicas in the gardens around the main building and mounted skeletons inside. Fig. 1. Welcome to Het Oertijdmuseum! I presume any visitor spots the glass fibre Tyrannosaurus before reading the notice on the right. Other saurians are lurking in the undergrowth around the main museum building, much to the delight of children of all ages. I am a walker and I prefer to saunter from the station through the attractive town of Boxtel to Het Oertijdmuseum rather than take a bus. The walk is a long 30 minutes. As you near the museum, the route passes a most extraordinary building, Bosscheweg 107, ‘Den Daalder’. This appears to be an entirely conventional office block until you reach the end closest to the museum, when all is … 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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Geomodels in engineering: An introduction

Peter Fookes, Geoff Pettifer and Tony Waltham (UK) This article is based on the introduction to the newly published book Geomodels in Engineering Geology – An Introduction. What, why and when? The Earth is an active planet in a constant state of change. These changes can take place over both long and short periods of geological time (thousands or millions of years) or much more quickly on an engineering timescale (minutes, hours or days). Geological processes continually modify the Earth’s surface, destroying old rocks, creating new ones and adding to the complexity of ground conditions: the so-called ‘geological cycle’. The all-important concept that drives this geological plate tectonics. The benefits geologists bring to construction projects must exceed the cost of their services — that is, they must accurately improve the engineer’s ground knowledge more cheaply and effectively than any other method. They must reduce the risk of geological hazards by anticipating situations perhaps unseen by the engineers and also help to determine effective ways of dealing with risks and any problems arising during design and construction. The main role of the engineer geologist is to interpret the geology and ground correctly. Creating an initial model for the geology of the site is an excellent start. Geology (the study of the Earth) and its closest geo-relative, geomorphology (the study of the Earth’s surface), are concerned with changes over time and any geomodel has to build in any changes likely to occur in the near future, especially when the construction project may … 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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Jade: Imperial green gem of the East (Part 2) – decorative and ornamental jade

Sonja McLachlan (UK) In the second part of this five-part series of articles, I will be exploring the beautiful examples of ornamental and decorative jade carvings that can be found in many places around the world. Ancient peoples collected and sculpted jade into unique symbolic items representing their own cultures and beliefs. Today, modern jade sculpting honours this ancient symbolism whilst introducing contemporary themes, thereby widening the appeal of this ancient art form. Maori Jade Carving The Maoris valued jade for its toughness and it was often made into weapons and tools such as adzes and chisels used for working with wood. Modern jade carving reflects the Maori traditions with new interpretations on fishhooks, circular koru pendants and beautiful double and triple jade twists that represent bonding and friendship. Models of Kiwis, Turtles and Dolphins can also be found carved in jade. Fig. 1. Maori-style Pendant, carved out of solid Jade. Inspired by Maori designs. Spiral – Koru – The fern fronds represent life, new beginnings, life unfolding, growth & harmony. The stylisation of Koru represents the spirit of rejuvenation. Fig. 2. Another Maori-style pendant, fish hooks – Hei Matau. Represents strength & determination. Brings peace, prosperity, abundance and good luck. It also provides safe transport over water. Chinese Jade Carving The highest quality Burmese Jade is sent to China where it is used for the finest objects and religious figures. It is often found in the grave furnishings of high-ranking members of the imperial family. The raw stone is … 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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Volcanism in the ancient world

Dr Robert Sturm (Austria) In the ancient Greek and Roman world, volcanism was recognised as a divine phenomenon standing in close connection with the fire god, Hephaestus or Vulcan. Although there did not exist any term corresponding to the modern word “volcano”, people were aware of the destructive power arising from volcanic eruptions. Some early natural philosophers were already able to identify individual volcanic processes, such as lava flow and the generation of huge and extremely hot dust clouds. In the ancient Greek language, lava masses streaming downhill were simply named “rhea” (ῥύαξ or flow), whereas the Latin words “Vulcanius amnis” (Vulcanic stream), “saxa liquefacta” (liquefied rocks) and “massa ardens” (blazing mass) were used for the same phenomenon. Volcanoes were of enormous importance for the ancient Mediterranean world, because their eruptions caused the destruction of adjacent settlements and even the annihilation of entire civilizations. According to our present historical and archaeological knowledge, three volcanoes had an immense influence on the development of Mediterranean cultures: (1) the volcano of Thira-Santorini, which left behind the huge caldera visible today; (2) Vesuvius near the city of Naples; and (3) Etna on the island of Sicily (Fig. 1). Fig. 1. A satellite map of the Mediterranean region, including the position of the three volcanoes covered in this article. Despite the Thira-Santorini volcano being situated in the Aegean Sea, Vesuvius near Naples and Etna on Sicily, they are all considered to be part of the western Mediterranean Sea. (Photo: ©NASA.) In this article, I intend … Read More

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Urban geology: The strange tale of a windowsill

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

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La Gomera: A short geological guide

Ken Madrell (UK) The island of La Gomera has an area of 370km2, it is 25km in diameter, has a maximum altitude of 1,487m (Alto Garajonay) and is situated approximately 40km west of Tenerife. Unlike the other Canary Islands, La Gomera has experienced a long and continuing eruptive break and is in a ‘postshield erosional stage’. Carracedo and Troll (2016) describe this as the stage when active volcanism has ceased, and erosive and denudational landforms are predominant (p. 39). The submarine base of the island shows that it rests on a shallower ocean bed than the surrounding islands. The emerged land mass is semi-circular in shape, with a radial drainage pattern from its centre near Alto de Garajonay. The dating of the island has proved problematic, as some of the earlier measurements placing its age between 15 Ma and 19 Ma have since proved to be inaccurate. More reliable estimates now put its age at between 10 and 11 Ma. Fig. 1. Roque Argando viewed from Lomo de la Mulata. La Gomera’s general stratigraphy comprises of three main rock sequences: A Miocene basaltic shield, including a basal plutonic complex (that is igneous rock formed by solidification at considerable depth beneath the earth’s surface).A nested felsic (that is, igneous rocks that are relatively rich in elements that form feldspar and quartz) stratovolcano (which is built up of alternating layers of lava and ash).The youngest Pliocene volcanism.Fig. 2. Sketch map of La Gomera, showing the main towns and geology of the island. … Read More

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Headbanging, rocking and moonwalking fossils

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

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

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

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Urban geology: Gabions in the Dutch townscape

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

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Fossil folklore: Molluscs

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

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Carrara marble from the Apian Alps: Another famous ancient workable stone

Dr Robert Sturm (Austria) This is the last in a series of four articles I have written on the quarries and marble of the ancient world and the works of art made from it. The others are Mining in Ancient Greece and Rome, Marble from the Isle of Paros in Ancient Greece – a tour of the ancient quarries and Roman quarries in Austria and Germany – a short sight-seeing tour. Therefore, after our tours to the famous quarries of the Isle of Paros and the Roman stone quarries in Central Europe, we come to another location, which is well-known for its workable stone. I am talking about the city of Carrara, with its marble of the same name. Carrara is located in the province of Massa and Carrara, in the so-called Lunigiana, which represents the northernmost tip of Tuscany in Italy. Carrara marble is a white to blue-grey rock of high quality that has become popular for its use in sculpture and building decor. The extraordinary characteristics of this rock were already recognised by the Romans, who started their mining activities in the second century BC. In ancient times, the marble was commonly referred to as “Luni” and used for the production of houses, figures and monuments. Due to the high demand for the workable stone, more and more quarry sites were exploited, which finally resulted in a total number of 650 mines. Today, about half of them are either abandoned or worked out. Historical studies provide evidence that … 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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