Synopses of Talks through the 2020 - 21 Winter Season
Wednesday 8th July
Contrasting Islands: the geology of Eigg and Rum
Angus Miller (Secretary Scottish Geology Trust)
The Hebridean islands of Eigg and Rum are separated by just a few miles of sea, but could hardly be more different in their scenery, topography and land use. Of course this is due to the underlying geology. Both islands have a basement of sedimentary rocks (formed 800 million years apart!). Then, 60 million years ago, this area was a focus of volcanic activity: Eigg is mostly formed by the eroded remains of extensive basalt lava flows; whereas Rum was the site of a central volcano. It is a fascinating clash of rock types and morphologies that has formed two contrasting islands.
Wednesday 19th August
Mining in North Wales
Robert W. Vernon BSc MSc PhD CGeol FGS (Rtd)
Parys Mountain Copper Mine, Anglesey
This talk will begin with an introduction to the geology of North Wales before discussing the most important minerals worked (copper, lead, gold, slate, coal and a few “miscellanea”). We will then take a round trip of the various mining districts, including perhaps the best known copper mine in Wales (at Parys Mountain on Anglesey), as well as the Parc lead and zinc mine at Aberconwy, and the Gilfach copper mine in Caernarvonshire, among many others.
Parc Mine (lead & zinc), Aberconwy, Conwy, North Wales. Gilfach Mine (copper) Caernarfonshire, North Wales
Wednesday 16th September
Jurassic calamari: new research on fossil squid-like cephalopods from the Wessex Basin
Professor Malcolm Hart (Emeritus Professor, University of Plymouth)
Discoveries of some exquisite specimens of the soft parts of squid-like cephalopods have been found in the fossil record in the Wessex Basin. They are around 190–160 million years old; and there is exceptional preservation of eyes; ink sacks; beaks and arm hooks. Balancing organs, 'statoliths', of aragonite have also survived, and show internal (daily?) growth lines.
There are specimens of fossil squid-like cephalopods in the Natural History Museum (London), and Lyme Regis Museum; some collected by both Mary Anning and Henry De La Beche. When the GWR railway was built from Swindon to Bristol, local palaeontologist Joseph Pearce uncovered fossils at Christian Malford that caused great excitement, as soft parts of squid-like animals were preserved. The ink sacks and the muscle scars survived, and reconstruction of the creatures from the arms, some with pairs of hooks, could be attempted. A specimen from Bristol Museum & Art Gallery has non-paired hooks, so there is a potential for identifying species. Scattered statoliths have been recorded, but cannot be linked to a named species. It has been argued that the white discs with hooks could have been suckers, but it is difficult to understand that a sucker with a hook in its centre could function effectively. The Christian Malford beds were re-opened, in 2008, by the BGS, and a core from the 'squid bed' was found to have earbones, or 'statoliths', scattered throughout. There is a need to relate these to a species, so CT scanning of specimens from Christian Malford is taking place in the Natural History Museum to see if this can be achieved. Different shaped hooks are now thought to exist on the same animal, as one specimen from Germany shows five different kinds, and there are interesting questions on the evolution of the hooks that we see in the geological record.
An ichthyosaur specimen in the Etches Collection appears to show hooks as stomach contents, but it is possible that these may have fallen onto the specimen after death.
The exceptional preservation of material is exciting, and there is plenty more research to be done. Recently, new specimens have been found, and cleaned, clearly showing the arrangement of hooks in the arms. An old specimen, from the BGS collections, has been shown to record the capture, and presumed feeding, of a squid-like cephalopod holding a fish (Dorsetichthys bechei); one of the earliest records of cephalopod predation.
Wednesday 30th September
Understanding Earths' climate during the Cambrian radiation of animals
Dr Tom Wong-Hearing (Leicester & Ghent, Belgium)
Fossils of the Cambrian Period (541-485 Ma) record an astonishing rise in animal abundance and diversity across Earths' oceans. Major advances in palaeontology over the last century have helped to illuminate the biological aspects of the Cambrian ecological revolution, but aspects of Earths' physical environment remain poorly understood. This talk illustrates some of the key advances that we have made, over the last few years, in quantitatively investigating Earths' climate in the early part of the Cambrian Period. Evidence is drawn together from two, independent, methods, to build up a global picture of the early Cambrian climate. Both approaches suggest that the early Cambrian world was warm, in a greenhouse climate state, with limited, or no permanent polar ice sheets. These independent approaches provide the first steps in establishing a quantitative framework for understanding Earths' climate during the Cambrian radiation of animals.
Wednesday 14th October
50 years of plate tectonics: past, current, and future, questions
Dr Marco Maffione (University of Birmingham)
The most unifying theory in Earth Sciences is that of Plate Tectonics, and it is one of the top five, most relevant, theories in the Sciences. Plate tectonics is the simple, and elegant, explanation of how our planet has been, is, and will be, shaped by the continuous movements and interactions of tectonic plates. I will guide you through the long journey of scientific discoveries that brought several scientists, with different backgrounds, to contribute to the birth of the plate tectonics theory; ultimately formulated just over 50 years ago. Since then we have understood much of how our planet works, which helped us. in the ‘90s, to reach a new, important, discovery on how our oceans expand. Today we still have several questions about key processes, such as the formation of new subduction zones, which represent new challenges for the current, and future, generations of Earth scientists.
Wednesday 21st October
From Coprolites to Cholera, the extraordinary life of William Buckland
Peter Lincoln (PhD Researcher, University of East Anglia)
William Buckland (1784-1856), Oxford’s first ‘Professor’ of geology, was a central figure of the ‘heroic’ foundational age of geological investigation. Buckland was a meticulous scientist and a devout, if sometimes rather too down-to-earth, clergyman. A charismatic lecturer, his flamboyant delivery stimulated his admirers, and scandalised his detractors, and, as a result, he was both venerated and vilified in life and, since his death, his eccentricities have often been more remembered than his achievements. However, Buckland’s foundational work in stratigraphy and palaeontology – his explanation of a hyena den at Kirkdale won him the Royal Society’s Copley Medal – and his early acceptance of glacial theory, put him firmly at the forefront of early nineteenth century geological endeavour. Equally at home with queens and quarrymen, William Buckland’s humanity shone through in everything he did. Appointed Dean of Westminster in 1845, he did not hesitate to use his new position to advocate scientific solutions to the problems of famine and disease. In this talk I shall aim to restore the memory of this geological hero by describing his long, and eventful, life, and outlining some of his many achievements, both in geology, and in the wider world.
Wednesday 28th October
Fire and Rain: exploring the links between weather, climate, and volcanism
Dr Jamie Farquharson (University of Miami)
It is well understood that volcanic activity can influence Earths' climate: the 1783 Laki, Iceland, eruption blasted enough sulphur dioxide into the atmosphere to cause a drop in global mean temperatures, with crop failures as far away as India. Similarly, ash from 1815 Tambora, Indonesia, circumnavigated the globe, reducing global temperatures, and was the critical factor leading to the 1816 'Year without Summer'. However, the inverse phenomenon - the initiation of volcanic activity due to external factors - remains both contentious, and poorly studied.
Discrete case study examples exist: research at a handful of volcanoes - such as Mount St Helens, Washington, USA; Soufrière Hills, Montserrat,; and Piton de la Fournaise, La Réunion - has demonstrated that volcanic activity can, on occasion, be triggered by heavy rainfall. Kīlauea Volcano, Hawai`i, USA, provides a recent demonstration of how rainfall may directly trigger the movement of magma from deep in the crust to the Earth’s surface. Indeed, historical patterns of Kīlauea’s eruptive activity suggest that its volcanic behaviour is often modulated by increased periods of rainfall, both seasonally and aseasonally. The question remains: are these geographically discrete examples purely random, or are they symptomatic of a prevalent underlying link between volcanic activity and the hydrological cycle?
With the advent of space-borne precipitation detection systems, we can explore this phenomenon on a global scale. We find that a significant correlation exists between eruption occurrence and the timing of the rainy season at several individual volcanoes, and across certain volcanic regions. Due to anthropogenic climate change, many parts of the world are anticipated to experience a change in annual mean precipitation and - potentially more importantly - increases in extreme precipitation. In the context of our ever-changing global climate, understanding external modulation of volcanic activity remains an important frontier topic.
Wednesday 18th November
The Jurassic Coast: the biggest story on Earth
Richard Edmonds (geologist and fossil collector, former Earth Science Manager for the Site; and the first warden of the Charmouth Heritage Coast Centre)
A look at the Dorset and East Devon coastal World Heritage Site;
185 million years of the Earth's geological history explored in the global context of plate tectonics, extinction events; and the evolutionary steps that eventually led to us.
Wednesday 2nd December
How useful is legacy oil and gas data for nascent geoenergy activities onshore the United Kingdom
Mark T Ireland (Newcastle University, School of Natural and Environmental Sciences, Drummond Building, Newcastle Upon Tyne, NE1 7RU)
The decarbonisation of energy systems, to achieve net zero carbon emissions, will likely require the rapid development of carbon capture and storage; energy storage in the subsurface and geothermal energy projects. Subsurface data, such as seismic reflection surveys and borehole data, will be vital for geoscientists and engineers to carry out comprehensive assessments of both the opportunities and risks for these developments. However, often, relative immature activities, such as the recent controversial hydraulic fracturing for shale gas in the UK, may be associated with greater subsurface uncertainty. This includes the geological uncertainties associated with resource characterisation, as well as the those which are associated with, potentially, negative environmental and societal impacts. What may have been considered an acceptable level of geological uncertainty for one activity in the past, may no longer socially be perceived as acceptable.
Through looking at the characteristics of legacy oil and gas datasets, aspects of geological uncertainty, in the deep subsurface of the UK. are explored. Specifically, the spatial coverage and chronology of the acquisition of key seismic reflection and borehole data, acquired for onshore hydrocarbon and coal exploration in the UK, are examined; as well as aspect of data resolution and limitations. The implications of the spatial variability in subsurface datasets. and the associated subsurface uncertainties, will be discussed, as this is vitally important to understanding the suitability of data for future geoenergy activities and decision making.
Despite over a century of subsurface data collection onshore UK, there remains significant subsurface uncertainties, which in part are due to the quality and accessibility of existing key subsurface datasets. An awareness of the limitations of available datasets is critically important when considering subsurface interpretations and modelling, which often assume perfect knowledge. Understanding the provenance and quality of data are vitally important for future geoenergy activities, and public confidence, in subsurface activities. There is still a relative paucity of both well, and seismic, data across the onshore UK, and considerable uncertainty in many of the models and predictions that are generated from these data.
Wednesday 9th December
The History and Hidden Gems of the Lapworth Museum of Geology
Aerona Moore (Learning and Engagement Officer at the Lapworth Museum of Geology) This lecture was hosted by the Warwickshire Geological Conservation Group
The Lapworth Museum of Geology holds the finest and most extensive collections of fossils, minerals and rocks in the Midlands. Dating back to 1880, it is one of the oldest specialist geological museums in the UK. Enabling visitors to explore life over the past 3.5 billion years, the Lapworth Museum showcases exceptional objects of both scientific and historical importance.
This talk will reveal the Museums fascinating history and its recent transformational redevelopment. Hear about the influential geologists who have contributed to the Museum’s collections, including Charles Lapworth, after whom the Museum is named. Explore some of the Museums hidden gems, favourite objects, and the fascinating stories they tell.
Wednesday 20th January
Castle Bank: a new Ordovician Burgess Shale-type fauna from Wales
Dr Joseph P Botting (Honorary Research Fellow at the National Museum Wales)
The Burgess Shale-type faunas of the Cambrian provide one of the best windows into ancient ecosystems, while preserving a remarkable range of soft-bodied organisms in extraordinary detail. Most remarkably, they represent the extremely diverse, normal marine assemblages of the open shelf sea floor, and have, therefore, revealed the Cambrian Explosion (arguably the most important interval in animal evolution) in previously unimaginable detail. There are two known Early Ordovician faunas of this type (in Wales and Morocco), but after that the window seems to have closed. Later Ordovician exceptionally- preserved fossil assemblages are more constrained, and limited in scope, often representing odd environments, or specialist ecosystems.
During the lockdown of 2020, a new Burgess Shale-type fauna was discovered in Middle Ordovician rocks of the Builth Inlier, central Wales. The fauna is in the preliminary stages of excavation, and interpretation, but has already yielded a remarkable range of lightly-mineralised, and soft-bodied taxa, including sponges, arthropods, several phyla of worms, molluscs and many other groups. The fauna is the most important Ordovician fossil discovery since the Fezouata Biota, and has the potential to revolutionise our view of Ordovician evolution and ecosystems.
Wednesday 10th February
Charnwood's Canadian Cousins: Recent Geological Discoveries from Newfoundland, and How They Inform Our Knowledge of England's Oldest Fossils
Dr Jack Matthews (Oxford University Museum)
Looking back to the distant Ediacaran Period (635-541 Ma), the beginning of the Phanerozoic Eon, when enigmatic tubular and frond-shaped, mostly sessile, organisms (and trace fossils), left their marks - the precursors to the Cambrian radiation. Recent discoveries in Newfoundland, Canada, can show how local celebrities discovered in Charnwood Forest, Leicester, England, came to be.
Wednesday 10th March
Earthquakes, normal faulting, and hazard in central Italy
Dr Zoe Mildon (UKRI Future Leaders Fellow Quake 4D project & University of Plymouth)
Central Italy frequently has damaging earthquakes, including most recently the 2009 L’Aquila earthquake and the 2016 Amatrice earthquake sequence. My research uses a combination of fieldwork, modelling and cosmogenic isotope dating, to try and understand how the faults have moved in the past, how the faults interact together and ultimately what is the seismic hazard of the region.
Wednesday 17th March
An Introduction to the Geology of Iceland
Stuart Blake (Director Lochranza Centre, Arran)
The geology of Iceland is unique. Situated on the divergent boundary between the Eurasian plate and the North American plate, it also lies above a hotspot, the Iceland plume. The plume is believed to have caused the formation of Iceland itself; the island first appearing over the ocean surface about 16 to 18 Ma. Upwelling commenced in the early Tertiary, and sea-bed core evidences 55 million year old rock. The result is an island characterised by repeated volcanism. Surtsey, a new volcanic island, was formed in 1967.
Geothermal phenomena, such as geysers, are a great natural resource.
Wednesday 24th March
Discovery of a meteorite ejecta layer at the base of palaeocene lavas, Isle of Skye, NW Scotland
Dr Simon M Drake (Research Associate, Birkbeck, UCL)
This talk highlights the discovery of a meteorite ejecta layer, discovered beneath the base of Palaeocene lavas, on the Isle of Skye, NW Scotland. The layer has also been located at two other separate sites, 7kms apart, on South Skye. Within the layer, shocked minerals from the country rock could only have been produced by an instantaneous impact event. Vanadium rich, and Niobium rich, Osbornite have also been found within the layer. These minerals have never been found on Earth before, and have only been recorded as comet dust, collected by NASA, from the Wild II comet trail. This ejecta layer likely acted as a driver for the volcanic episode within the wider British Palaeogene Igneous Province. The layer has been subjected to geo-vandalism, wide media coverage, and is now under the protection of the John Muir Trust, and Scottish Natural Heritage.
Wednesday 31st March
The keys to the past: a mixed-methods approach to reconstructing the 1812 eruption of La Soufrière St. Vincent
Dr Jazmin P. Scarlett (Historical and Social Volcanologist)
The usage of a wide range of qualitative and quantitative data, and integrating them in creative and compelling ways, with a pragmatic underpinning, can provide deep investigations into the impacts of volcanic eruptions on society. The 1812 eruption of La Soufrière volcano, on the Lesser Antilles island of St. Vincent, was reconstructed with a mixed-methods approach in mind. This eruption occurred during the slavery era, when there was a reliance on enslaved labour to cultivate the island’s sugar monoculture. Findings have found that the eruption produced ash fall; pyroclastic density currents (PDCs); volcanic earthquakes; and lahars that impacted 129 plantation estates, leading to 43 documented deaths. This eruption also forced the emigration of the indigenous Kalinago, and the purchasing of land for displaced enslaved Africans. Lastly, a key aspect of this eruption was that due to the estate owners receiving loans, the focus was to “return back to normal”, and not to adapt; essentially meaning that the dimensions of vulnerability and risk did not change as a result.
Monday 12th April
Ethiopia from top to bottom: using seismology to understand how tectonic plates rise, split, then fall
Dr Ian Bastow (Senior Lecturer in Seismology, Imperial College, London)
To an Earth Scientist, Ethiopia is a truly remarkable place. Its highest mountain, Ras Dashen, stands 4550m tall; its lowest point, the Danakil Depression, lies some 150m below sea level. From space, the immaculate jigsaw fit of the Somalian, Arabian and Nubian tectonic plates is un-mistakable. On closer inspection, active volcanoes, and earthquakes, provide daily reminders that this is a region that remains in a state of geological development. Active geological processes pose significant hazard, but also a remarkable opportunity for scientists curious about how tectonic plates break into two. In this talk, I will discuss how decades of work by seismologists, like me, have helped us understand how Ethiopia has come to be so topographically, and geologically, interesting. Our journey will take us from the core-mantle boundary, some 2891km below our feet, to the surface. I will also discuss how the lessons that we have learned, from the Horn of Africa, have helped shed new light on how continents have broken apart through geological time.
Wednesday 21st April
The Life and Work of Henry Clifton Sorby: Sheffields' Greatest Scientist
Dr Noel Worley (British Gypsum, rtd)
Outside Sheffield, and outside geology and metallurgy, the name Henry Clifton Sorby is little known, and even within these circles, all that is known by many is the name. This is not surprising, but it is regrettable, for apart from his outstanding achievements in a wide variety of scientific fields, the life of the man is interesting from a number of viewpoints.
So wrote Norman Higham, in 1961, in his biographical study of Sorby’s life. The subsequent fifty years has perhaps been more generous, and his accomplishments have received widespread international recognition.
The purpose of the talk is to review his principle successes, to examine the circumstances surrounding Henry Clifton Sorby’s life in Sheffield between 1826 to his death in 1908; and to explain the key influences that led him along the path of scientific discovery. His greatest triumphs were undoubtedly in the development and application of microscopic techniques and he is regarded throughout the world as the father of petrography, metallography and sedimentology. He unleashed the power of the microscope in theinvestigation of meteorites and his work in this area has never been bettered. He was the first to use the microscope in forensic science, and the first to study inclusions in crystals.
Sorby devoted the whole of his life to scientific enquiry working solidly until his death. He was motivated by the spirit of original investigation and never sought the attention that his achievements merited. He was a powerful force in the development of higher education in Sheffield, whose university he helped to establish, and was a pioneer in the promotion of the provision of facilities for original scientific research.