Deposits Earth Science Archive
An acclaimed international collection of articles and book reviews on fossils, geology, minerals, palaeontology and earth science
The most visually arresting fossils from the West Cumberland Coalfield, indeed from almost any British Carboniferous site, are the great patterned slabs of lycopsid bark that, if you are lucky, can sometimes be found. Their surfaces carry unmistakable geometric signatures: the diamond-shaped leaf cushions of Lepidodendron or the vertical rows of elongated scars typical of Sigillaria.
The fossils described in this series formed during the Carboniferous Period, around 320 million years ago, when Britain lay close to the Equator. The above figure places the Carboniferous within Britain’s wider geological history. During this interval, extensive tropical wetlands covered much of the country, producing the peat deposits that would later become the coal seams of the West Cumberland Coalfield. This series explores one remarkable record of that vanished landscape.
A quiet valley at Grasmere holds clues to a landscape once buried beneath ice. By following those clues west to Langdale and then outward across the Lake District, a much larger story emerges – one of glaciers, ice sheets and landscape transformation.
Modern Britain lies far from active plate boundaries. It has no active volcanoes and experiences only minor earthquakes, and is often described as tectonically quiet. Yet its landscape is anything but passive. Hills and lowlands, coastlines and drainage patterns all reflect a deep structural inheritance established during earlier phases of continental collision, collapse and rifting.
Matthew Myerscough’s In Search of Sea Dragons: A Fossil Hunter’s Odyssey begins not with fossils, but with survival. Early in the book, Myerscough recounts how he and his future wife narrowly escaped death in an avalanche on Snowdon. The experience casts a long shadow over everything that follows. What initially appears to be a book about fossil hunting, gradually reveals itself as something rather more personal: a memoir about recovery, obsession, friendship and the strange hold that collecting can exert over people.
Heather Middleton, Mike Harvey and Steve Snowball (UK) This article describes a series of pliosaur remains recovered from the Lower Kimmeridge Clay Formation at Smallmouth Sands, Weymouth (Dorset). The material, collected as isolated elements from a single locality within the Rasenia cymodoce Biozone, includes cervical and caudal vertebrae, ribs and … Read More
By the end of the Carboniferous, Britain had already passed through more than one major phase of mountain building, each followed by long periods of erosion and structural collapse. The Caledonian mountains were long eroded, and the Variscan belt of southern Britain was entering its final stages of decay. Yet tectonic influence did not fade away. Instead, the dominant regime changed. Britain was no longer being compressed – it was being stretched.
The collision that assembled Britain at the end of the Silurian (see A history of the plate tectonics of Britain (part 1): Britain assembled – oceans, collisions and the making of a geological patchwork) did not mark the end of tectonic influence on the landscape. Instead, it marked the beginning of a new phase – one that is often less intuitively grasped, but just as important. Mountain belts are temporary features. Once continental collision ceases, thickened crust becomes gravitationally unstable. Erosion strips material from the surface, while extension and faulting affect the deep roots of the orogen. The geological record that follows is not one of rising peaks, but of collapse, subsidence and redistribution.
Steve Snowball (UK) This article is a response to a request by the editor of Deposits to write about my inspiration and reasons for writing a series of fossil collecting guides, the latest of which is A Field Guide to Collecting British Cenozoic Fossils, by myself and Alister Cruickshanks, and … Read More
Britain is often described as geologically quiet. There are no active volcanoes, no subduction zones, and only modest earthquakes. Yet, for its size, few countries display such a concentration of geological variety. Mountain uplands, volcanic terrains, deeply folded rocks, and ancient metamorphic cores all occur within a relatively small area. The explanation for this diversity lies not in Britain’s present tectonic setting, but in a long and complex tectonic history that assembled the country piece by piece from fragments that originated far apart.
Books devoted specifically to collecting Britain’s Cenozoic fossils are surprisingly rare. While collectors are well served by guides to the country’s Palaeozoic and Mesozoic fossils, the younger deposits that record the last 66 million years of Earth history have received far less attention. A Field Guide to Collecting British Cenozoic Fossils aims to address that gap by providing a practical introduction to the fossils and collecting sites associated with these deposits.
For much of the twentieth century, generations of students (and amateurs like me) learned a tidy, mid-Cretaceous succession for southern England:
Lower Greensand – Gault Clay – Upper Greensand – Chalk.
It appeared in every textbook, diagram and museum panel. There was an appealing symmetry to the sequence, with two sands bracketing the impervious Gault and the Chalk resting neatly above. It seemed so natural that few doubted it.
Robert J Williams (UK) To the north-east of London lies the county of Essex, which extends out to the east coast of England. Although not noted for its geology, it does have quite a bit to offer the amateur geologist. In addition, there is a significant body of published geological … Read More
Stephen K Donovan (UK) If asked what is my favourite fossil collecting site, I would have to say the Farquhar’s Beach oyster bed on the south-central coast of Jamaica. I taught at the University of the West Indies for over 12 years and this locality was an easy drive. In … Read More
This is the first of three articles on the Carnian Pluvial Event (CPE), often referred to as an ‘event’, although increasingly recognised as a prolonged episode, as I will discuss) of the Triassic that seems to have grown in importance and interest, and only become more widely known in relatively recent times. In this article, I will introduce the topic, concentrating on what might be called the “climate engine” driving what was happening.
I found the pebble almost by accident, while staying with friends near Eccleshall in Staffordshire. We had taken their two dogs (the much missed Holly and Chutney) out for an afternoon walk – the kind of slow, stop-start loop where the dogs dictate the pace and the conversation meanders as much as the footpath. Along a muddy stretch of track, something smooth and rounded caught my eye: a faintly banded, reddish stone lying half-buried among the usual Midlands gravel and mud.
Jon Trevelyan (UK) This is the second of my series of short articles on fossils of the Ediacaran Period. Charniodiscus is one of the most characteristic frondose organisms of the Ediacaran Period, living around 560-555 million years ago in the quiet, low-energy seafloors that preceded the Cambrian explosion. With its … Read More
The Classic Geology in Europe series has, over many years, established a distinctive and reliable identity: authoritative regional syntheses written by specialists, designed for geologists who want to understand landscapes through field observation rather than armchair generalities. The Southern Pennines sits comfortably within that tradition and, in several respects, exemplifies the mature strengths of the series.
Jon Trevelyan (UK) This is the first of my series of short articles on fossils of the Ediacaran Period. Charnia is one of the most iconic fossils of the Ediacaran Period, known for its elegant frond-like form and its place among the earliest large, complex organisms in Earth’s history. First … Read More
Stephen K Donovan (UK) The south of England in the late 1940s and 1950s must have been a wonderland for the field palaeontologist. There were still many working or recently discarded quarries. Transport was easy and affordable by rail and bus. Visits to quarries were rarely difficult. It was a … Read More
At first glance, the title might mislead you into expecting a simple guide to finding fossils while strolling along the beach – a sort of field companion for holiday rock-hunters. But Stephen Donovan’s Fossils on the Seashore is a very different creature. It’s not about collecting curiosities for the mantelpiece. It’s about understanding the dynamic relationship between the living and the fossil record, and how coastlines act as natural laboratories for palaeontological and neoichnological study
Ru D A Smith (Malaysia, UK) Aragonite is a common mineral in the skeletons of marine organisms (Cusack & Freer, 2008), but is not typically well preserved in the fossil record due to its tendency to recrystallise as its more stable polymorph calcite. Certain circumstances can however enhance the preservation … Read More
Denis Bates and Anna Kozłowska (Poland) Graptolites (grapto + lithos = writing in the rocks) are common Palaeozoic fossils – found from the Cambrian to the Carboniferous. Usually, they are preserved as flattened and altered remains in mudrocks, particularly the black shales or slates known as “Graptolitic Shales” (Fig. 1), … Read More
WAJ Rutter (UK) On 2 June 2011, a large slab of faunal tracks was found in Scalby Bay, north of Scarborough (Fig. 1). These footprints were immediately recognised as not being dinosaur footprints due to the size, shape and distribution of the tracks. They were in a fallen block, which … Read More
Jason Sherburn, (UK) Living near the coast is amazing. Or, at least, that’s how I imagine it to be for budding fossil collectors intent on unlocking the mysteries of the ancient world. However, I live about 50 miles from the coast and, while my own area is not topographically dull, … Read More
Jon Trevelyan (UK) Recently, I spent a few days on my own down at one of my favourite fossil hunting sites – Copt Point and East Wear Bay in Folkestone. As readers probably know, the Gault Clay at Folkestone is a marine sedimentary deposit from the Lower Cretaceous (Albian) period, … Read More
Paul Cox (UK) During the 1980s, the secretary of the local branch of my professional association was famous for arranging field trips to places of interest. By and large, these had nothing to do with my profession, but they were nevertheless interesting places. One day, he had arranged a visit … Read More
