Hertfordshire Geological Society

Notes from Deep Time – A journey through past and future worlds
2023-09-14 19:30 - 21:00 UTC | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
given by Helen Gordon, (University of Hertfordshire & author of Notes from Deep Time).
An exploration of the world of deep time and what it means to be human within the context of 4.5 billion years. From stratigraphers, volcanologists and palaeontologists to writers, artists and semioticians, this talk will draw on a series of conversations with the men and women who live and work in deep time.
View this talk in the Members’ Section.

GA Lecture via Zoom
2023-10-06 18:00 - 20:30 | over Zoom
Gold Mining and the Welsh Connection given by Mark Austin, Alba Mineral Resources PLC

A short history of buildings in six stones
2023-10-12 19:45 - 21:00 | Hartoak Room, Mansion House, Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
given by Dr. Tim Yates, (Technical Director, Building Research Establishment, Garston.

Doors open at 7:15pm, tea & coffee available, talk starts at 7:45pm.

Many will be familiar with Neil MacGregor’s ‘A history of the world in 100 objects’ that retell humanity’s history through the objects we have made. This talk is on a much smaller scale with just six objects – all natural stones! But hopefully they will help us to see how our built heritage, our built landscapes, our towns, cities and villages, are shaped by the natural stones used in their construction.
Along the way we’ll look at the links to geography, society, technology, and politics – and, of course, the geology of the rocks from which the stones were taken.
Why six stones? Well there’s no real reason but six felt about right in the time we have! And choice of the six – Caen Limestone, Clunch, Portland Limestone, Welsh Slate, York Sandstone, and Aberdeen Granite – includes some of the most important building stones found in the UK but is also a personal choice that reflects my background and my work at Building Research Establishment for the last 37 years.

HGS Warwickshire Field Trip
2023-10-14 12:00 - 2023-10-15 17:00 | The Gret Western Arms, Station Road, Blockley, Moreton-in-Marsh, GL56 9DT
We have a day and a half in the field planned with the help of the Warwickshire Geo-Conservation Group. The outline schedule is as follows:
Saturday morning
Drive to the village of Blockley in the Cotswolds
Lunch (TBC) – The Great Western Arms
Saturday afternoon
Northcot Brick Works to visit the Blockley Brickpit

We will be met by Dale Moss – Works manager. Lower Jurassic (Charmouth Formation) led by Dr. Jon Radley (Warwick Museum).
This is a very fossiliferous site and the WGCG made a video of a previous visit – view that here.
It will be muddy!
Saturday evening
Find your own overnight B&B accommodation in the Stratford on Avon, Evesham and Warwick area.

Possible dinner meet up
Sunday all day
Meet with Dr. Stuart Burley (University of Keele) at Inkberrow, followed by Henley in-Arden & the Grand Union canal to study the Triassic (Carnian) Arden Sandstone. A recent Geology Today article for this is available from Haydon if you’d like one.
If you’re interested in attending this trip, then please notify Haydon as soon as possible at haydonbailey@outlook.com .

Geologist's Association Festival of Geology
2023-11-04 | University College London, Gower Street, London, WC1E 6BT, United Kingdom

From shallow mine workings to deep basement rocks: A tour of UK low temperature geothermal resources
2023-11-09 19:30 - 21:00 | over Zoom
given by Dr. Cat Hirst (Senior Engineering Geologist, COWI, Glasgow)
From shallow mine workings to deep basement rocks: A tour of UK low temperature geothermal resources
Catherine M. Hirst1, Sally Jack1,2
1COWI UK Ltd, Fifth Floor, 310 St Vincent Street, Glasgow, G2 5RG.
2University of Strathclyde, 16 Richmond St, Glasgow, G1 1XQ, UK.
The UK has committed to be net zero by 2050 via the signing of the 2015 Paris Agreement and 2021 Glasgow Climate Pact. Space heating in the UK accounts for 42% of UK energy demand, and natural gas is used to provide more than 90% of this heating and cooling demand. De-carbonising heat, therefore, has the potential to make a huge impact on the UK’s net zero aspirations.
Over the past 25 years, research into geothermal energy extraction from low enthalpy (temperature) resources within the UK has been increasing year-on-year. Whilst historically the UK has only ever had one working low temperature deep geothermal system (Southampton), there is scope for geothermal energy to make a significant contribution to the UK energy portfolio. More recently, focus has fallen on the shallow (typically <500 m depth) geothermal systems associated with old, abandoned mine workings. Our understanding of these systems is incomplete in the same way we have limited knowledge of the deep (>500 m depth) subsurface, but what sets shallow resources apart from deeper resources is their accessibility. This talk aims to cover the background to geothermal heat generation, the key differences between shallow and deep low temperature geothermal resources, provide examples of deep low temperature resources in the UK and to showcase the work currently being completed by the University of Strathclyde and COWI to better characterise mine water geothermal resources.
View this talk in the Members’ Section.

Dinosaurs: New Visions of a Lost World
2023-12-12 19:30 - 21:00 | over Zoom
given by Prof. Mike Benton (Professor of Vertebrate Palaeontology, University of Bristol)

Twenty-five years ago, the first feathered dinosaur was reported, Sinosauropteryx. There has been a revolution in dinosaur palaeobiology since then, driven by thousands of amazing specimens from China plus new analytical methods.
In 2010, we were among the first to develop a new analytical method to identify the colour of feathers, including the feathers of dinosaurs. Suddenly the ancient world came to life!
Since then, the methods have been criticised, tested, and applied to many exceptional fossils of dinosaurs and birds, and the plumage colours and patterns reconstructed. These methods are scientific, meaning they can be tested (and so far they have withstood critical testing), and they make definite predictions about the colours of dinosaurs and other extinct animals.
Order a copy here: https://bit.ly/DinosaursNewVisions
More information:
https://thamesandhudson.com/dinosaurs-new-visions-of-a-lost-world-9780500052198
https://dinocolour.blogs.bristol.ac.uk/
View this talk in the Members’ Section.

Outcrops & Subsurface examples of the EoCambrian petroleum system in Oman
2024-01-11 19:30 - 21:30 | over Zoom
Talk by Professor Stuart Harker, Retired.
Southern Oman has one of the oldest working petroleum systems in the world with source rocks, reservoirs and productive traps in the Huqf Supergroup (520-600mya). There are superb world class outcrops of these sediments exposed along the Indian Ocean coast and in the inland salt diapir province. Reservoirs range in depositional environment from glacial clastics to peritidal stromatolitic carbonates. Petroleum traps range from conventional tilted fault blocks and anticlines, through salt induced anticlines to rafted carbonates and silicilyte. In spite of over 70 years of exploration, there remain many opportunities to discover additional reservoirs and traps.
View This Talk In The Members’ Section.

The Thames in Hertfordshire and adjacent areas
2024-02-08 19:30 - 21:30 | over Zoom
Talk by Professor David Bridgland, University of Durham.
Hertfordshire would seem to be the only one of the Home Counties to have been abandoned by the Thames during the Quaternary. It was squarely on the Thames course prior to southward diversion of the river ~450,000 years ago, the result of Britain’s most extensive glaciation. The evidence for the erstwhile Hertfordshire Thames will be pieced together during the lecture, with comparison made with neighbouring areas that have also furnished parts of the story and have supplied more recent refinements.
View This Talk In The Members’ Section.

Annual General Meeting
2024-03-14 19:45 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
AGM will be followed by refreshments after which members are invited to share slides on the theme of 50 years of HGS in the field!

Percy Evans Lecture: Surfing the Waves of Time: Exploring Latin America's Passive Margins with an Innovative Sea Level Curve
2024-04-11 19:45 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Dr. Douwe van der Meer, CNOOC International, Uxbridge
Abstract: Recent exploration efforts in South American passive margin basins, such as the Guyana-Suriname Basin, have yielded significant success with over 10+ Bboe discovered, primarily within the late Cretaceous play/mega-sequence. Most recently the Southern Atlantic margin, spanning Brazil, Uruguay, and Argentina, has also garnered industry attention, particularly following discoveries at the conjugate margin of Namibia.
In an award-winning study by Van der Meer et al. (2022), plate tectonic eustasy estimates were updated using the 87Sr/86Sr record of seawater, coupled with a novel glacio-eustasy estimates based on a recent Phanerozoic paleotemperature model (Scotese et al., 2021). This innovative Tectono-Glacio-Eustatic (TGE) curve for the entire Phanerozoic correlates well with mega-sequence stratigraphy in global passive margin basins.
Examining key basins like Guyana, the TGE curve aligns with the mega-sequences, showcasing the influence of plate tectonic and glacio-eustatic drivers on the petroleum system. The petroleum system elements in deepwater, correlate well with predictable patterns.
Similarly, southern Atlantic basins also exhibit predictable elements of the drift play (post-Aptian), with the TGE curve serving as a tool for undrilled sections of the stratigraphy. This research underscores the interplay between plate tectonics, glacio-eustasy, and basin evolution, offering valuable insights for future and ongoing exploration endeavours.
Biography: Douwe van der Meer, a tectonophysicist by background, and seasoned explorationist by profession, earned his M.Sc. at Utrecht University in 2002, specializing in plate tectonic processes. Following a transformational sabbatical at the Norwegian Geological Survey in 2009, he continued research on plate tectonics, which led to a Ph.D. cum laude in 2017 and was recently honoured with the IAGR Best Paper award and medal. With over 20 years of experience at Shell, Nexen, and CNOOC, Douwe has led various exploration New Ventures teams, being based in the Netherlands, UK, and USA. A passionate Earth System enthusiast, Douwe’s work and research encompasses all continents and eras from the Archean to Cenozoic. Currently serving as Sr. Manager New Ventures Latin America at CNOOC International, Douwe continues to contribute his research expertise to the industry. His commitment to advancing understanding of Earth Systems, coupled with significant applications to the oil and gas sector, establishes him as subject matter expert in global exploration.
View This Talk In The Members’ Section.

Identification and implications of the London Clay Formation divisions from an engineering perspective
2024-05-09 19:45 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Dr. Jamie Standing, Imperial College London
Abstract: Historically, engineers viewed the London Clay (LC) Formation as uniform, homogeneous and rather uninteresting. Chris King’s seminal work provided a much deeper insight into the characteristics of the LC and how it can be split into divisions, based on the depositional history of the formation and the microfauna present. LC water content profiles were compiled from continuous cores as part of an investigation into variations in tunnelling-induced settlements across St James’s Park, allowing distinct zones to be identified. These were found to coincide exactly with the divisions identified by Chris King almost twenty years earlier. Water content profiles can be developed as part of a ground investigation and used to help establish the boundaries between King’s divisions. Based on two further water content profiles from Hyde Park and St John’s Wood a new methodology for locating the boundaries of the divisions, involving a trend-line for sub-Division A3, is proposed and tested, relevant to conditions in central London. In developing the method, significant differences in the elevation of the divisions between the three sites is observed, suggesting geological processes such as folding or faulting have influenced the LC along the 5-km length of the section. Once the boundaries of the LC divisions are known, geotechnical engineers have a greatly improved overall understanding of the ground conditions and how the ground will respond to engineering works such as tunnelling and deep excavations. Broad engineering implications of the divisions are described and discussed, citing case histories where possible.
View This Talk In The Members’ Section.

Fossils and the history of life course
2024-06-07 19:00 - 2024-06-09 13:00 | University of Cambridge, University of Cambridge, Cambridge, Cambridgeshire, CB23 8AQ, United Kingdom
Delivered by Dr Peter Sheldon for the University of Cambridge Institute of Continuing Education (ICE).
Course Overview
Suitable for beginners as well as those with some previous knowledge. You will see how fossils get preserved, sometimes in surprising detail, and learn how to recognise some common fossil groups. Our look at major events in the history of life will include the latest discoveries and discuss the significance of mass extinctions, such as when the dinosaurs died out. We will end by considering the influence of own species on the biosphere. There will be a chance to study many real fossils put out in the teaching room.
This course (with optional accommodation) includes 7 x 90-minute sessions delivered between Friday evening and Sunday lunchtime with plenty of opportunity for further conversations and networking during breaks and mealtimes.
For more details and how to book click here.

Spying on open vent volcanoes from ground, air and space
2024-06-13 19:45 - 21:30 | over Zoom
Talk by Dr. Emma Nicholson (Liu), University College London
Abstract:
“Open vent” volcanoes are persistently active and maintain an unbroken connection between shallow magma reservoirs and the atmosphere. These volcanoes are true natural laboratories, providing an unparalleled window into the subsurface physical and chemical processes that control volcanic activity. Open vent volcanoes sustain large volcanic gas emissions and are therefore the “chimney pipes” of our planet, responsible for shaping the Earth’s atmosphere over geological time and impacting regional air and water quality on human timescales. Lava lakes are rare end-members in the expressions of open vent volcanism and can remain stable for years to decades. Yet, recent events at Kilauea (Hawaii), Ambrym (Vanuatu) and Nyiragongo (DRC) have emphasized how rapidly these lakes can drain to feed voluminous flank eruptions, posing substantial environmental and societal hazards. I will review some of the recent advances and outstanding questions in our understanding of the mechanisms and impacts of open vent volcanic activity. In particular, I will focus on how remote sensing observations—from the ground, air and space—combined with studies of erupted volcanic rocks are providing new perspectives on the long-term eruptive behaviour of open vent volcanoes. This talk will draw on new insights from a National Geographic expedition to one of the most remote active volcanoes on Earth – Mt Michael, located in the South Sandwich Islands at the gateway to the Southern Ocean.
View This Talk In The Members’ Section.

Painting with Stone: Materials, Methods and Traditions in Pietre Dure
2024-07-11 19:45 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Talk by Dr. Ruth Siddall (University College London)
Abstract:
The talk will introduce the history, techniques and materials used in the decorative art of pietre dure (hard stone work). Almost every stately home and museum has a table-top or other object decorated with pietre dure and yet the craftmanship and materiality of the technique has been one of the most disregarded topics of study within the decorative arts. The technique of making patterns with coloured stones began in Antiquity and then found a renaissance in 15th Century Europe and was used equally for adorning large objects of furniture and small items such as stuff boxes and jewellery. The technique remained popular until the 19th Century in Europe and continues to be used in architecture and the decorative arts in Asia and particularly in India. The choice of stones used often has a specific connection to the workshops and therefore a knowledge of decorative stones used is essential for assigning a provenance to works made using the pietre dure technique.
View This Talk In The Members’ Section.

Summer Event - The Water Table II: Where does all the water go?
2024-07-20 10:00 - 16:00 | Affinity Water Ltd, Tamblin Way, Hatfield, Hertfordshire, AL10 9EZ, United Kingdom

Modelling the Atmospheres of Tidally-locked Terrestrial Exoplanets
2024-09-12 19:30 - 21:30 | over Zoom
Talk by Dr. Andrew Rushby, Birkbeck College, University of London unfortunately had to be cancelled. We hope to reschedule the talk and include it in our 2025 programme.
Abstract
The climates of terrestrial planets are affected by their host star, the properties of their atmospheres, as well as any land, ocean, and icy surfaces, in predictable but also complex ways. I will provide a short introduction to the novel climatologies of tidally-locked (synchronously-rotating) planets in the orbit of small, cool M-Dwarf stars, highlighting recent ensemble and climate model intercomparison studies have been used to uncover some of the effects of the complex, ‘non-Earth-like’ rotational regimes of these worlds, which are likely common in our galaxy, on their possible climates and habitability by presenting some results from my recent work, as well as that of my students, collaborators, andcolleagues working in this area.
If time allows, I will also discuss the NASA ‘Research Coordination Network’ (RCN) model (of which NExSS was the first) and the means by which the astrobiology research and funding landscape within NASA, and beyond, is evolving to meet the needs of interdisciplinary scientists working in the field to leverage upcoming NASA, ESA, JAXA etc. missions, analogue studies, and observational platforms.
Bio – Dr Andrew Rushby is a Lecturer in Astrobiology and Programme Director of the MSc. Astrobiology programme in the School of Natural Sciences at Birkbeck, University of London.

Snowball Earth

The Geology of the Albert Memorial
2024-10-03 17:45 - 19:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Talk by Professor John Cosgrove, Imperial College London.
Which will be followed by a visit to the Albert Memorial on Saturday 5 October 2024.

Visit to the Albert Memorial and a journey through time
2024-10-05 09:00 - 14:30 | The Albert Memorial, Kensington Gardens, London, W2 2UH, United Kingdom
led by Professor John Cosgrove, Imperial College London. This visit follows on from the talk on the same subject given by John on the previous Thursday.
If you’re intending to go, can you please contact Haydon Bailey as soon as possible at haydonbailey@outlook.com so that we have an indication of numbers attending.
11:00 – meet at the Albert Memorial, South Kensington to investigate the geological aspects of the memorial
13:00 – independent lunch at one of the local hostelries or cafes
14:30 – reconvene at the entrance to the new Natural History Museum Urban Garden where we will take a walk through time and explore how the NHM has used rocks and fossils to exhibit the history of the earth.
When you contact Haydon can you please indicate if you wish to attend just the morning session or both sessions.

Unveiling the geology of Mars with robotic explorers
2024-11-14 19:30 - 21:30 | over Zoom
Talk by Dr Joe McNeil, Natural History Museum, London.
Abstract:
Before the first observations of Mars by orbiting spacecraft in the 1970s, it was widely thought that the red planet resembled Earth’s Moon in its geology. However, decades of robotic exploration by orbiters, landers, and rovers alike have radically reshaped our understanding, revealing Mars’ unique and complex geological history. Abundant evidence of past liquid water on its surface reveal processes both familiar from Earth and others that are entirely unique to Mars. In this talk, we will cover an overview of Mars’ geology, discuss how geological investigations of Mars are conducted from orbital and landed spacecraft, and explore the geological mysteries of Oxia Planum, the future landing site of the European Space Agency’s ‘Rosalind Franklin’ ExoMars Rover (launching in 2028).
View This Talk In The Members’ Section.

Perseverance examines martian geology

The Rutland Ichthyosaur: Digging up a 'Dragon’
2024-12-12 19:30 - 21:30 | over Zoom
Talk by Dr. Emma Nicholls, Oxford University Museum of Natural History
Abstract:
The full-scale excavation in 2021 uncovered the largest near-complete reptile
skeleton ever found in Britain. The animal nicknamed the ‘Rutland Sea Dragon’,
would have been around 10m long, in life, and is thought to be the first confirmed
record of its species, Temnodontosaurus trigonodont, found anywhere in the world
outside of Germany. In this lecture we will hear about the highs, lows, blood, sweat
and plaster, of the dig.
View This Talk In The Members’ Section.

More adventures in the Lambeth Group - how understanding stratigraphy helps engineering understanding
2025-01-09 19:30 - 21:00 | Zoom Talk
Desiccated Reading Formation clays around the London Underground Jubilee Line between Baker Street and Bond Street stations. Image is in the public domain at Bowers, Keith, and Neil Moss, 2018. “Investigation and reconstruction of a London Underground tunnel, UK.” Proceedings of the Institution of Civil Engineers-Civil Engineering. Vol. 171. No.

50th anniversary lecture by Dr. Jackie Skipper, Geotechnical Consulting Group & GSL William Smith Medal Winner.

Abstract:
The highly variable Paleocene Lambeth Group is today understood far better than even 25 years ago. Boreholes and engineering exposures for major civil engineering projects have provided clarification into how these sediments were formed, what engineering hazards they can cause and how we can manage these if we have a good understanding of the ground.
View This Talk In The Members’ Section.

Scotland’s Greatest Ice Age
2025-02-13 19:30 - 21:00 | Zoom Talk
Talk by Emeritus Professor Ian Fairchild, University of Birmingham
Abstract:
The Port Askaig Formation were the first Precambrian rocks interpreted as glacial in origin, anywhere in the world. Now we know that Neoproterozoic glaciation was global in distribution. The exposures of the Port Askaig Formation are also the best permanent exposures of glacigenic deposits of any age in the British Isles and have attracted much international interest. Over a decade of study by an interdisciplinary team have led to many new insights that will be presented in a Memoir of the Geological Society of London. There is an informal proposal that the base of the Cryogenian geological System should be located here on the Garvellach Islands of western Scotland.
Ian Fairchild’s contributions to Neoproterozoic geology have focused mainly on Svalbard and Greenland, as well as Scotland. In relation to the Port Askaig rocks he has sought to understand the association of dolomite with glacigenic facies and the significance of the glacial record both on the Garvellachs and the Isle of Islay.
View This Talk In The Members’ Section.

AGM & Launch of the Hertfordshire 50th anniversary book
2025-03-13 19:30 - 21:00 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Annual General Meeting followed by refreshments & The Launch of the Hertfordshire 50th anniversary book

Epping Forest through geological time
2025-04-10 19:45 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
48th Percy Evans Lecture given by Mike Lambert, HGS Honorary President
As a child, Epping Forest was my playground, where I climbed trees, made dams and rode my bike. But there was one way in which it disappointed me. When I began collecting fossils and minerals and taking an interest in Geology, it seemed to have nothing to offer. Real Geology, so it seemed to me, only existed in places like Lyme Regis and Scotland.
This talk is my attempt to set the record straight and appreciate the many wonders that exist in and under Epping Forest. After describing the Epping Forest Ridge in its regional context, I’ll work my way up a stratigraphic column, from the oldest rocks of the Palaeozoic basement to the youngest superficial deposits. Along the way, we’ll examine discoveries made from roadworks in the 1970s, see how Anglian ice turned rivers back-to-front and visit a Neanderthal hunting and butchery site.
View this talk in the Members’ Section.

Sea Level Change in the Anthropocene
2025-05-08 19:45 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Talk by Dr. Colin Summerhayes, Emeritus Associate, Scott Polar Research Institute, University of Cambridge
Abstract:
Given the magnitude and rapid rise of greenhouses gases(including water vapour), their long lifetime in the atmosphere, and the present disequilibrium in Earth’s energy budget (expressed as the Earth’s Energy Imbalance, or EEI), both temperatures and sea level must continue to rise – even with carbon emissions lowered to net zero (where anthropogenic CO2 emissions = anthropogenic CO2 removals) – until the energy budget balance is eventually restored. Due to the natural lags between temperature rise, ice melt, and sea level rise, it will take a few centuries for this equilibrium point to be reached. There is a high probability that sea level rise will reach at least 1m (range 0.9-1.8m) above 1900 levels by 2100. During past warmer-than-present interglacials, sea level commonly reached between 4-9m above 1900 levels and occasionally between 12-15m above (much as in the warm periods of the mid-Miocene and mid-Pliocene).
Unfortunately due to technical problems this talk was not recorded.

Adventures of an Argon geochronologist: Why do we date rocks?
2025-06-12 19:30 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Talk Dr Sarah Sherlock, Senior Research Fellow, The Open University
Abstract:
My current preoccupation is to find new ways in which we can increase the spatial resolution of Ar/Ar laserprobe dating to extract new information from rocks and minerals. Through this I, and colleagues, are investigating the diffusion mechanisms of argon in feldspars, understanding the behaviour of argon during friction melting, the uptake of excess argon in mudrocks and their attendant strain-fringes, the timing of fluid-rock interaction through dating authigenic alkali feldspars, dating meteorite impact craters, the behaviour of argon in volcanic glasses, and most recently in basalts. Recent work in Turkey provides examples of the use of Ar39/Ar40 dating techniques and how they can be used in the geological interpretation of regional igneous and tectonic provinces.

Summer Event - Water Table III Understanding Our Aquifer
2025-07-04 09:00 - 16:00 | Cambridge Geological Society, Babbage Lecuture Theatre, new Museums Site, Pembroke Street, Cambridge, CB2 3QZ, United Kingdom

Thames Through Time - with a Cornish flavour
2025-07-10 19:45 - 21:30 | Oaklands College, Sapsed Room (SR), Oaklands College, St Albans, Hertfordshire, AL4 0XS, United Kingdom
Talk by Ian Mercer from the Essex Rock & Mineral Society.
Abstract:
Ian Mercer reveals the story of the Thames across Essex by digging into the landscape in and around the county. The Thames has changed course dramatically and repeatedly throughout the past two million years of the current ice age. The greatest impact of the Thames upon the landscape is during times of cold, when Spring thaws create mighty torrents of water. River-bed gravels have been deposited while the land has been tilting gradually throughout this time, resulting in ‘staircases’ of gravel terraces across the landscape and beneath the temporary flood of the North Sea.
During this time, the rivers have brought rocks from across the area of southern Britain as evidence of their journeys. These include beautiful black-and-white pneumatolytic quartz-tourmalinite from around the granite intrusions of the South-West. Ian has collected many of these from across Essex and East Anglia and has grown to love them. He reveals their evidence in the land and in church walls. The Thames will change again many times as climate continues to oscillate.

Golden Anniversary Dinner
2025-07-19 | The Wellington, 1 High Street, Welwyn, Hertfordshire, AL6 9LZ, United Kingdom
Details to follow nearer the time
