Wed 29 May 14:00: Title to be confirmed
Abstract not available
- Speaker: Patrick Smith -- Dublin Institute for Advanced Studies
- Wednesday 29 May 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre (virtual).
- Series: Bullard Laboratories Wednesday Seminars; organiser: Janneke de Laat.
Wed 29 May 14:00: Title to be confirmed
Abstract not available
- Speaker: Patrick Smith -- University of Leeds
- Wednesday 29 May 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre (virtual).
- Series: Bullard Laboratories Wednesday Seminars; organiser: Janneke de Laat.
Wed 12 Jun 14:00: Title to be confirmed
Abstract not available
- Speaker: Gianmarco Mengaldo -- NUS, Singapore
- Wednesday 12 June 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Adriano Gualandi.
Wed 05 Jun 14:00: Title to be confirmed
Abstract not available
- Speaker: Brad Foley -- Penn State University
- Wednesday 05 June 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: nobody.
Wed 08 May 14:00: Title to be confirmed
Abstract not available
- Speaker: Kristel Chanard -- IPGP, Paris
- Wednesday 08 May 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Adriano Gualandi.
Wed 01 May 14:00: Title to be confirmed
Abstract not available
- Speaker: Max Werner -- University of Bristol
- Wednesday 01 May 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Adriano Gualandi.
Wed 24 Apr 17:30: Natural and forced behaviour of the Pacific Walker Circulation over the past 800 years Building doors are card operated, so latecomers may not be able to access the venue.
The Pacific Walker Circulation (PWC) is an important part of the global climate system, and affects weather and climate all over the world. However, our observational records of the climate system are too short to characterise the PWC ’s long-term internal variability, as well as how the PWC responds to external forcings such as volcanic eruptions and anthropogenic forcings.
In this seminar I will share a reconstruction of the PWC ’s behaviour over the past 800 years. I will outline how I calculated this reconstruction using a network of globally-distributed water isotope proxy records, as well as how I quantified uncertainties from different sources. I will share some new insights this reconstruction has allowed, including a close examination of the PWC ’s response to both volcanic and anthropogenic forcing.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Georgina Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 05 Jun 17:30: Extreme glacial implies discontinuity of early human occupation of Europe Building doors are card operated, so latecomers may not be able to access the venue.
The oldest known hominin remains in Europe [ca. 1.5 to 1.1 million years ago (Ma)] have been recovered from Iberia, where paleoenvironmental reconstructions have indicated warm and wet interglacials and mild glacials, supporting the view that once established, hominin populations persisted continuously. We report analyses of marine and terrestrial proxies from a deep-sea core on the Portugese margin that show the presence of pronounced millennial-scale climate variability during a glacial period ca. 1.154 to 1.123 Ma, culminating in a terminal stadial cooling comparable to the most extreme events of the last 400,000 years. Climate envelope–model simulations reveal a drastic decrease in early hominin habitat suitability around the Mediterranean during the terminal stadial. We suggest that these extreme conditions led to the depopulation of Europe, perhaps lasting for several successive glacial-interglacial cycles.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Vasiliki Margari, University College London
- Wednesday 05 June 2024, 17:30-19:00
- Venue: Harker 1, Department of Earth Sciences, Downing Street.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 24 Apr 14:00: Carbon subduction and mid-ocean ridge emissions modulate icehouse-greenhouse climates
The cycling of carbon between the deep Earth and the atmosphere plays a significant role in modulating global climate. While carbon degassing at volcanic arcs are generally assumed to be the main contributor to atmospheric carbon, our research reveals that mid-ocean ridge degassing surpasses arc emissions before 50 Ma. Combining thermodynamic modelling of subducting carbon reservoirs with reconstructions of remobilised crustal carbon through the Phanerozoic, we show that volcanic arc emissions reduce to merely ~12% of mid-ocean ridge outflux before 120 Ma. This reflects the absence of deep-sea carbonate sediments entering subduction zones, leaving less voluminous metamorphic degassing of continental carbonate platforms next to convergent margins as the main mechanism for arc CO2 degassing. We find that the balance between oceanic volcanic outgassing and removal of carbon via subduction tracks major climate shifts, including the Late Palaeozoic, Late Cretaceous and Cenozoic icehouse climates.
- Speaker: Ben Mather, University of Sydney
- Wednesday 24 April 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Megan Holdt.
Wed 22 May 14:00: Title to be confirmed
Abstract not available
- Speaker: Arwen Deuss - Utrecht University
- Wednesday 22 May 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Lisanne Jagt.
Tue 30 Apr 12:00: Fresh perspectives on the origins of major animal groups: insights from the late Ediacaran of Namibia
Abstract not available
- Speaker: Alex Lui, Department of Earth Sciences, University of Cambridge
- Tuesday 30 April 2024, 12:00-13:00
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Department of Earth Sciences Seminars (downtown); organiser: Dr Rachael Rhodes.
Wed 24 Apr 14:00: Carbon subduction and mid-ocean ridge emissions modulate icehouse-greenhouse climates
The cycling of carbon between the deep Earth and the atmosphere plays a significant role in modulating global climate. While carbon degassing at volcanic arcs are generally assumed to be the main contributor to atmospheric carbon, our research reveals that mid-ocean ridge degassing surpasses arc emissions before 50 Ma. Combining thermodynamic modelling of subducting carbon reservoirs with reconstructions of remobilised crustal carbon through the Phanerozoic, we show that volcanic arc emissions reduce to merely ~12% of mid-ocean ridge outflux before 120 Ma. This reflects the absence of deep-sea carbonate sediments entering subduction zones, leaving less voluminous metamorphic degassing of continental carbonate platforms next to convergent margins as the main mechanism for arc CO2 degassing. We find that the balance between oceanic volcanic outgassing and removal of carbon via subduction tracks major climate shifts, including the Late Palaeozoic, Late Cretaceous and Cenozoic icehouse climates.
- Speaker: University of Sydney
- Wednesday 24 April 2024, 14:00-15:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Megan Holdt.
Thu 02 May 11:30: A molecular-level description of the oxygen evolution reaction using in situ spectroscopy
Water electrolysis stands as a cornerstone technology for green hydrogen production from renewable energy and consists of two half-cell reactions: the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). The sluggish kinetics of the state-of-the-art OER electrocatalysts based on iridium oxide severely limit the overall efficiency of the process and, consequently, its economic viability. An in-depth comprehension of the atomic-level mechanisms governing this reaction is considered essential for designing enhanced materials and advancing the transition to a sustainable and resilient energy sector. In situ structural characterization techniques, such as X-ray absorption spectroscopy and X-ray photoelectron spectroscopy, serve this purpose well as they enable real-time monitoring of the chemical composition, structural phase, and electronic configuration of the species at the gas/liquid/solid interface during the interfacial electrocatalytic turnover. In this talk, I will present an overview of the experimental approaches developed in our group and by others to probe the reactive interface during OER , as well as our current understanding of the reaction mechanism on Ir-O-based systems gained using both soft and hard X-ray spectroscopic techniques.
References
1) R Arrigo, M H ävecker, ME Schuster, C Ranjan, E Stotz, A Knop-Gericke et al.,
In situ study of the gas-phase electrolysis of water on platinum by NAP -XPS,
Angewandte Chemie International Edition 52 (2013), 11660-11664
2) JJ Velasco‐Velez, V Pfeifer, M H ävecker, RS Weatherup, R Arrigo et al., Photoelectron spectroscopy at the graphene–liquid interface reveals the electronic structure of an electrodeposited cobalt/graphene electrocatalyst, Angewandte Chemie International Edition 54 (2015), 14554-14558
3) A Knop-Gericke, V Pfeifer, JJ Velasco-Velez, T Jones, R Arrigo et al., In situ X-ray photoelectron spectroscopy of electrochemically active solid-gas and solid-liquid interfaces, Journal of Electron Spectroscopy and Related Phenomena 221 (2017), 10-17
4) V Pfeifer, TE Jones, JJV V élez, R Arrigo, S Piccinin, M H ävecker et al., In situ observation of reactive oxygen species forming on oxygen-evolving iridium surfaces, Chemical science 8 (2017), 2143-2149 5) V Pfeifer, TE Jones, S Wrabetz, C Massué, JJV V élez, R Arrigo et al., Reactive oxygen species in iridium-based OER catalysts, Chemical science 7 (2017), 6791-6795
6) JJ Velasco-Vélez, EA Carbonio, CH Chuang, CJ Hsu, JF Lee, R Arrigo, et al., Surface electron-hole rich species active in the electrocatalytic water oxidation, Journal of the American Chemical Society 143 (2021), 12524-12534
7) JJV V élez, D Bernsmeier, TE Jones, P Zeller, E Carbonio, CH Chuang, et al., The rise of electrochemical NAPXPS operated in the soft X-ray regime exemplified by the oxygen evolution reaction on IrO x electrocatalysts, Faraday discussions 236 (2022), 103-125 8) J Ruiz Esquius, DJ Morgan, G Algara Siller, D Gianolio, M Aramini et al., Lithium-directed transformation of amorphous iridium (oxy) hydroxides to produce active water oxidation catalysts, Journal of the American Chemical Society 145 (2023), 6398-6409 9) M Falsaperna, R Arrigo, F Marken, SJ Freakley Alkali Containing Layered Metal Oxides as Catalysts for the Oxygen Evolution Reaction, ChemElectroChem 2024, e202300761
- Speaker: Rosa Arrigo, Uni of Salford
- Thursday 02 May 2024, 11:30-12:30
- Venue: Open Plan Area, Institute for Energy and Environmental Flows, Madingley Rise CB3 0EZ.
- Series: Institute for Energy and Environmental Flows (IEEF); organiser: Catherine Pearson.
Tue 23 Apr 11:00: Sedgwick Club Conference 2024
Six talks from a variety of areas of Earth Sciences; large igneous provinces, ice core climate records, modern ocean climate systems, earthquake dynamics, geoscience communication and the Earth’s magnetic field. Also featuring highlights from industry and a Part III poster presentation session.
- Speaker: N/A
- Tuesday 23 April 2024, 11:00-16:00
- Venue: Common Room, Department of Earth Sciences.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Tue 23 Apr 16:30: What has Earth's magnetic field ever done for us? The role of the geodynamo in creating a habitable planet (Sedgwick Club Conference)
When considering why Earth is the only known habitable – and inhabited – world in our solar system, its magnetic field is often included as one of the many factors resulting in such favourable conditions for life. This is because magnetic fields protect planetary surfaces from harmful cosmic radiation and prevent the atmosphere from being eroded by the solar wind. Earth’s magnetic field is generated by the geodynamo; vigorous convection of electrically conductive molten metal in the outer core results in the dipolar magnetic field that surrounds our planet. We can use the signals preserved by magnetic minerals in rocks to examine the strength of Earth’s magnetic field back through geological time. However, this becomes increasingly challenging as metasomatic and metamorphic events cause these minerals to be altered or entirely replaced. Paleomagnetic records suggest that Earth’s magnetic field has been similar in strength for the last 3.5 billion years. However, there are many time periods with sparse data, and the existing data come with many caveats. New experimental approaches are now allowing paleomagnetists to revisit Earth’s early magnetic field history in a new light by combining magnetic microscopy, geochronology and petrology. By recovering more accurate records of Earth’s magnetic field strength through time questions such as how the geodynamo behaved prior to the nucleation of the inner core, and the role of Earth’s magnetic field in mediating atmospheric escape, can be addressed properly for the first time. These observations will be critical for determining whether the magnetic field really played a crucial role in creating habitable conditions on Earth’s surface.
- Speaker: Dr Claire Nichols - University of Oxford
- Tuesday 23 April 2024, 16:30-17:00
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Tue 23 Apr 14:45: Journey to the centre of the earthquake (Sedgwick Club Conference)
Earthquakes are a dramatic result of our dynamic planet. They pose a huge issue to the world’s population in terms of loss of life and damage to critical infrastructure. Recent research tells us that tectonic faults can creep slowly, produce ‘slow’ earthquakes over days, or fast earthquakes that travel at supersonic speeds. What have we learnt about earthquakes over the past few years that helps us to understand these different types of faulting movements? This presentation will outline different types of tectonic fault slip and explore the methods we are currently using to enhance our understanding of earthquakes.
- Speaker: Professor Daniel Faulkner - University of Liverpool
- Tuesday 23 April 2024, 14:45-15:15
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Tue 23 Apr 15:45: A journey in (geo)science communication (Sedgwick Club Conference)
From dodgy pubs in West London to the Royal Institution Christmas Lectures, I’ve been lucky to talk to many people about the important role geoscience plays in our everyday lives. But what have I learnt along the way? And can anything I’ve found out help us talk more productively with the public about the importance of science in society, especially as we face significant challenges such as climate change?
- Speaker: Professor Chris Jackson - Jacobs
- Tuesday 23 April 2024, 15:45-16:15
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Tue 23 Apr 14:00: Towards developing an Indian Ocean Dipole Watch System for Southeast Asia (Sedgwick Club Conference)
TBC
- Speaker: Dr Shipra Jain - University College London
- Tuesday 23 April 2024, 14:00-14:30
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Tue 23 Apr 11:30: Destruction and regrowth of lithospheric mantle beneath large igneous provinces (Sedgwick Club Conference)
Large igneous provinces (LIPs) are formed by enormous (i.e., frequently >106 km3) but short-lived magmatic events that have profound effects upon global geodynamic, tectonic, and environmental processes. Lithospheric structure is known to modulate mantle melting, yet its evolution during and after such dramatic periods of magmatism is poorly constrained. Using geochemical and seismological observations, we find that magmatism is associated with thin (i.e., ≲80 km) lithosphere and we reveal a striking positive correlation between the thickness of modern-day lithosphere beneath LIPs and time since eruption. Our results point to systematic destruction and subsequent regrowth of lithospheric mantle during and after LIP emplacement and recratonization of the continents following eruption. These insights have implications for the stability, age, and composition of ancient, thick, and chemically distinct lithospheric roots, the distribution of economic resources, and emissions of chemical species that force catastrophic environmental change.
- Speaker: Simon Stephenson - University of Oxford
- Tuesday 23 April 2024, 11:30-12:00
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Thu 02 May 11:30: TBC
Abstract not available
- Speaker: Rosa Arrigo, Uni of Salford
- Thursday 02 May 2024, 11:30-12:30
- Venue: Open Plan Area, Institute for Energy and Environmental Flows, Madingley Rise CB3 0EZ.
- Series: Institute for Energy and Environmental Flows (IEEF); organiser: Catherine Pearson.