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Fossil fishes of the Old Red Sandstone of Scotland

Dr Neale Monks (UK) While they can be found in many other parts of the British Isles, Scotland is uniquely associated with Palaeozoic fossil fishes. That Scotland’s fossil fishes are so well known is largely thanks to a remarkable man from Caithness, called Hugh Miller. Where scholars had dismissed the Old Red Sandstone as lacking in fossils, Miller found many finely preserved fossil fishes. He published several books on field geology including, in 1841, his most famous work, The Old Red Sandstone. This eminently readable book described the formation in great detail and included dozens of beautiful engravings that illustrated the fossil fishes he had discovered. Fig. 1. Dipterus – Achanarras Quarry (© Dr Jens Rydell). What is the Old Red Sandstone? The Old Red Sandstone is a distinctive set of sandstone rocks dominated by sediments laid down under non-marine, relatively dry climate conditions. It is predominantly Devonian in age, though, in Scotland at least, certain parts may be as old as Middle Silurian. This makes it much older than the formation known as the New Red Sandstone, which was laid down during the Permian. Fig. 2. Milleosteus remains from Thurso. (© Dr Jens Rydell.) Geologists can find Old Red Sandstone sediments across much of the British Isles, from Cornwall in the southwest of England to the Orkney Islands off the northeast tip of Scotland. For the most part, the Old Red Sandstone is indeed red thanks to the large quantities of iron oxide it contains, but, at some localities, … Read More

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Geology museums of Britain: Whitby Museum, Yorkshire

Dean Lomax and Jon Trevelyan (UK) By the early nineteenth century, geology in England had started to appeal to the public at large. For instance, in 1824 the Reverend William Buckland of Oxford University named the first dinosaur (Megalosaurus bucklandii) and, after this, it seems that this awe inspiring group of prehistoric animals had taken hold of the public’s imagination in ways that continue today. At the same time, several organisations had sprung up to cater for this increased interest in geology, many of which would go on to form the geological societies and museums that still exist today. The small coastal town of Whitby in North Yorkshire has been associated with fossils for hundreds of years. The geology of the area consists of highly fossiliferous, Lower Jurassic rocks from the Pliensbachian to Bajocian, with three main fossil bearing layers – the Whitby Mudstone, Saltwick and Dogger formations. (Rocks from the Pleistocene and Holocene can also often be found on the beaches washed in from the North Sea.) It was the highly fossiliferous nature these local rocks and, in particular, the discovery of prehistoric animals around Whitby (especially, marine reptiles), together with the increasing scientific interest in them, that prompted the formation of the Whitby Literary and Philosophical Society. It was this society that later founded Whitby Museum in 1824. Fig. 1. The Whitby Museum house many fossils from the the local area, including plesiosaur and icthyosaur remains. (© Whitby Literary and Philosophical Society.) Whitby Museum, often ignored or unheard … Read More

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Field trip to the building stones of Canterbury

Trevor Devon (UK) Eleven members of the Hastings and District Geological Society (HDGS) assembled in front of the Canterbury Law Courts on a fine Sunday morning in June 2010 to meet up with our guide for the day, Geoff Downer. Geoff had previously given a talk to HDGS in the spring on the building stones of St Augustine’s Abbey and clearly had a great passion for this subject (he calls it a “hobby”). The day was spent on a gentle walk around the eastern part of Canterbury, largely taking in St Martin’s Church, St Augustine’s Abbey and Canterbury Cathedral. Geoff provided a fascinating commentary on the geology, history, archaeology and architecture of the area, and stopped at appropriate sites to explore and identify the building stones more fully. Given that Canterbury had been an important major Roman town, and given its subsequent ecclesiastical history from Saxon to Norman and medieval times, there was no shortage of material to see. After a brief introduction to the geology of the Ouse Valley, we took a short walk to look at the thirteenth century Conduit House (Fig. 1), a well-preserved example of medieval water technology that was used to collect groundwater from the natural springs of the surrounding hills and gravity feed it down to St Augustine’s Abbey using lead pipes. The reservoir and tunnels are constructed of all sorts of stone, using some reclaimed material from the nearby city and the structure would originally have borne a circular roof. From this fascinating … Read More

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I, a Geologist (Part 1): The geology of Charles Darwin

Stephen K Donovan and Cor F Winkler Prins (The Netherlands) “Darwin … devoted 1383 pages of notes to geological topics, compared with only 368 pages to biological topics.” – (Rhodes 1991, pp. 194-195) Like the writer, Johann Goethe, who inscribed himself in the guest book of Karlsbad – present day Karlovy Vary, in the Czech Republic – as “J.W. Goethe, Geognost”, Charles Darwin considered himself a geologist (“I, a geologist” citation from his notebooks in Herbert 2005, p. 2), and rightfully so. He was a true savant and an amateur in the positive sense of the word, as commonly used in the seventeenth and eighteenth centuries (see Rudwick 2004, p. 23), This is despite the fact that he belonged, for some time after his return with HMS Beagle, to the geological elite (Rudwick 1982). This may be deduced, for example, from the fact that he was asked to write the part on geology of a naval manual (Darwin 1849). Early geological influences: Edinburgh, Cambridge and Lyell’s Principles “Henslow then persuaded me to begin the study of geology [in 1831] … [T]he sagacious Henslow ¼ advised me to get and study the first volume of the Principles, which had just then been published, but on no account to accept the views therein advocated.”  (Darwin 1983, pp. 39, 59) Darwin’s geological education took a new direction as he read volume one of Lyell’s Principles of Geology (Fig. 1) on-board HMS Beagle. However, his instruction in the new science actually began when he attended formal … Read More

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Moeraki Boulders: The giant marbles of New Zealand

Tasman Walker (Australia) Scattered over Koekohe Beach on the South Island of New Zealand, dozens of huge spherical boulders look like the remains of a monster game of marbles. These were recently featured on the cover of Issue 22 of Deposits. The grey, stone balls are a fascinating tourist attraction, about 70km north of Dunedin, near Moeraki, a small town on the Otago Coast. Some boulders stand alone, but most sit in clusters, with the waves splashing over them at high tide. Many lie broken into segments on the sand. Fig. 1. Large, small and broken boulders. The boulders are spectacular examples of concretions, which form when a mineral precipitates and cements the loose grains of sediment into solid rock. As you walk down the steep bluff to the beach, you can see other enormous boulders still embedded in the uncemented mudstone, but being exposed as the ocean waves erode the loose embankment. They eventually fall onto the beach. Fig. 2. Popular with tourists. The boulders come in two distinct sizes: the diameters of the smaller ones range from 46cm to 92mm, but the larger ones are 137cm to 200cm in size. The largest ones weigh almost 20 tons. Most are spherical, but a few are slightly squashed in a direction parallel to the bedding of the mudstone in which they formed. Although fascinating, the boulders are by no means unique. In New Zealand, you can find similar ones on a beach just 12km south, and others on the North … Read More

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Urban geology: Boulders and the Dutch

Stephen K Donovan (The Netherlands) My late wife, Dr Trina MacGillivray, was a geomorphologist. She loved the Netherlands and the Dutch landscape, but more than once made astute comparisons with the scenery of other northern European countries. The Dutch landscape, if it has a fault, is too organised, too well arranged and too manicured. Woe betide the blade of grass that dare step out of line. Trina’s observations extended to Belgium. If travelling to Brussels by train, it is immediately obvious when you have crossed the border because the landscape relaxes. It is not unruly or untidy, but, unlike the Netherlands, it does not need to maintain a near-geometric precision. Trina liked her trips to Belgium, too. These memories were revived on a recent bus ride from Leiden to Hoofddorp, near Amsterdam Schiphol International Airport. It was a grey, overcast day – the sort of dreary weather that the Netherlands does too well and too often. Even before we had left Leiden, the regular geometry of the town impressed itself on me. But then there was something in the central reservation that caught my eye – a cluster of irregularly rounded boulders of various lithologies (Fig. 1E, F). It occurred to me then that such clusters of boulders were not so unusual in the Dutch landscape, breaking up the geometry in unusual ways (Figs. 1 to 3), yet were undoubtedly man-made. Fig. 1. Boulders in Leiden, 4 February 2015. (A) The boulder garden, a favourite of all children who like … Read More

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Collecting minerals around the world

 Trevor Devon (UK) At some time, I suppose we have all collected rocks or minerals when we were travelling to new places, mostly as mementos, but nothing quite beats the buzz of collecting specific minerals from classic locations with like-minded colleagues. This type of collecting implies you know something of the geology and mineralogy of the location, what sort of rock to explore (often with a sledgehammer to start with) and what colour and shape the minerals are likely to be found in. Of course, it helps to travel with colleagues who have been there before and can show you what to look for. That is one of the reasons why I joined the Sussex Mineralogy and Lapidary Society (SMLS) a few years ago. Fig. 1. Behind the scenes at the mineralogy department of the Royal Ontario Museum, Toronto. Since 1980, SMLS has conducted trips to many parts of the world, including the USA and Canada, India, Namibia in Africa, and several countries in Europe. Such trips usually attract around a dozen or so participants and are often organised with a bit of tourism so that non-mineralogical spouses can join in. I have been fortunate enough to join recent SMLS trips to Cornwall, Isle of Skye, India, the South of France, the USA, Canada, the Caldbeck Fells in Cumbria, and Bulgaria. Perhaps I should start with the basic question of why I collect minerals. First of all, I think some of us are born collectors – for example, I collect … Read More

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Geological expedition along the southwest coast of Scotland

Dr Robert Sturm (Austria) Compared to the geological architecture of other European countries not exceeding a total area of 100,000km², the geology of Scotland is characterised by an unusual diversity of geological features. Due to its tectono-metamorphic complexity Scotland attracted numerous earth scientists in the eighteenth and nineteenth centuries, whose main aim was the development of theories about, on the one hand, rock formation and, on the other, metamorphic alteration of initial lithologies. Besides being the preferred target of foreign scientists, the country has also produced its own important figures in the history of geological research. In this context, James Hutton – the “father of modern geology”, after whom, for example, ‘Hutton’s Unconformity’ at Siccar Point in Berwickshire is named – has to be mentioned, but also Hugh Miller and Archibald Geikie provided valuable contributions to the enlightenment of various geological problems. Fig. 1. Geological subdivision of Scotland into four main units. Returning to the geology of Scotland, it is possible to subdivide the country into four main geological and geographical units. The Southern Uplands, which extend south of the Southern Uplands Fault, are mainly composed of sedimentary rocks dating back to the Silurian and the Devonian. The Central Lowlands or Midland Valley, which border the Southern Uplands Fault on the north, represent a rift zone that chiefly comprises Palaeozoic rocks of both sedimentary and volcanic origin. North and west of the Highland Boundary Fault lies the Highlands and Islands, which, due to their geological diversity, can be further subdivided … Read More

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Rival theories by English amateurs: Matley, Trechmann and the geological origin of Jamaica

Stephen K Donovan (The Netherlands) The two most significant geologists to visit Jamaica and study its geology between the two World Wars were both British: Charles Alfred Matley (1866-1947) and Charles Taylor Trechmann (1885-1964). Both had active research programmes in Jamaica and the Antilles in the 1920s and 1930s, mainly on subjects that did not overlap, but the one geological concept on which they strongly disagreed was the one that underpinned all of their work – the geological evolution of the Caribbean basin. C A Matley Charles Matley (Fig. 1A) was a career civil servant and distinguished amateur geologist. He studied at the Birmingham and Midland Institute and the Mason Science College. The latter was incorporated into the new University of Birmingham in 1900. At Mason College, he was taught by Charles Lapworth, the father of the Ordovician System and one of the principal debunkers of Murchison’s assignment of the Scottish Highlands to the Silurian (Oldroyd, 1990). Matley’s principal field research while at Birmingham was on the Precambrian and Lower Palaeozoic of North Wales (for example, Matley, 1899, 1900, 1928), particularly Anglesey, work for which he was awarded a DSc by the University of London in 1902. Of particular relevance to his Jamaican research was his understanding of the geology of the Llyn Peninsula and Anglesey (McIlroy and Horák, 2006). Fig. 1. (A) Charles Alfred Matley (1866-1947), probably in about 1935 at the earliest (after Donovan, 2008, fig. 2). (B) Charles Taylor Trechmann (1884-1964), date of image unknown (after Donovan, … Read More

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Geology and fossils of the Spilsby Sandstone Formation of Nettleton, Lincolnshire, UK

The Jurassic/Cretaceous boundary interval is represented in Lincolnshire by the Spilsby Sandstone Formation, a shallow water marine deposit that spans the Volgian stage of the Jurassic to the Berriasian stage of the Cretaceous (Hopson et al. 2008). The ammonite faunas of this formation are of particular interest, exhibiting affinities with correlative forms in both Russia on the Siberian plain, as well as Greenland and Canada (for example, Casey, 1973; Mikhail Rogov, personal communication 2015).

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Book review: A Pocket Guide to Geological Field Recording, by Alan Richardson

This is a brief guide explaining how the reader may collect meaningful data at outcrop level and make provisional identifications of common lithologies. It is not intended as a comprehensive field geology textbook and assumes that readers have already studied geological theory (and, as such, is probably most useful of the undergraduate, but could be interesting for anyone interested in geology).

Book review: Walking the Jurassic Coast: Dorset and East Devon: The Walks, the rocks, the fossils, by Ronald Turnbull

There are a lot of guide books to the Jurassic Coast Work Heritage Site. This one is intended to provide a useful introduction to the general geology of the coastline, dealing with its formation, fossils and plate tectonics (among many other things), but specifically in the context of walks – for both afternoon rambles and long distance hikes for the more committed.

Book review: Introducing Mineralogy, by John Mason

I have been fortunate enough to review for this magazine a large number of books from the Dunedin series of guides introducing aspects of the different sciences, especially the earth sciences. And Introducing Mineralogy continues the high standard set by its predecessors. It is slightly larger than some of the other guides in the series, but is still beautifully illustrated, nicely written and very informative.

Book review: Geology and Fossils of the Hastings Area (2nd ed), by Ken Brooks

I remember buying the first edition of Ken Brook’s fascinating little guide on Hastings a long time ago, and bumbling off to Hastings in the hope of finding Lower Cretaceous dinosaurs and tree ferns. Sadly, I was disappointed, as the area is not as productive as, say, the Dorset or North Yorkshire coastlines. Having said that, I have been back a few times armed with that first edition and have enjoyed the visits every time.

Book review: Classic Geology in Europe 3: Iceland, by Thor Thordarson and Ármann Höskuldsson

Iceland seems to set the hearts of certain geologists racing and, reading this field guide, it is abundantly clear why. Set out in this concise and authoritative book is the evidence of how this strange piece of rock – astride the Mid-Atlantic Ridge – is a “natural laboratory”, where the earth sciences can be watched in dramatic real-time.

Book review: Guides to: The Jurassic Coast; The Lake District; and Cornwall, by Robert Westwood

These three guides by Robert Westwood are in the same simple format. All are local geological guides to specific areas of the UK and all are illustrated by lovely full colour photographs. They all contain simple, introductory geological introductions for the uninitiated, and then more detailed expositions of what makes the regions so special.