Fri 09 Feb 16:00: Seismicity distribution and fault plane solutions from the 2021 Fagradalsfjall dyke intrusion, Reykjanes Peninsula
Abstract not available
- Speaker: Esme Glastonbury-Southern
- Friday 09 February 2024, 16:00-17:00
- Venue: Tea Room, Old House.
- Series: Bullard Laboratories Tea Time Talks; organiser: David Al-Attar.
Ancient seafloor vents spewed tiny, life-giving minerals into Earth’s early oceans
Their study, published in Science Advances, examined 3.5-billion-year-old rocks from western Australia in previously unseen detail and identified large quantities of a mineral called greenalite, which is thought to have played a role in early biological processes. The researchers also found that the seafloor vents would have seeded the oceans with apatite, a mineral rich in the life-essential element phosphorus.
The earliest lifeforms we know of—single-celled microorganisms, or microbes—emerged around 3.7 billion years ago. Most of the rocks that contain traces of them and the environment they lived in have, however, been destroyed. Some of the only evidence we have of this pivotal time comes from an outcrop of sediments in the remote Australian outback.
The so-called Dresser Formation has been studied for years but, in the new study, researchers re-examined the rocks in closer detail, using high magnification electron microscopes to reveal tiny minerals that were essentially hidden in plain sight.
The greenalite particles they observed measured just a few hundred nanometres in size—so small that they would have been washed over thousands of kilometres, potentially finding their way into a range of environments where they may have kick-started otherwise unfavourable chemical reactions, such as those involved in building the first DNA and RNA molecules.
“We’ve found that hydrothermal vents supplied trillions upon trillions of tiny, highly-reactive greenalite particles, as well as large quantities of phosphorus,” said Professor Birger Rasmussen, lead author of the study from the University of Western Australia.
Rasmussen said scientists are still unsure as to the exact role of greenalite in building primitive cells, “but this mineral was in the right place at the right time, and also had the right size and crystal structure to promote the assembly of early cells.”
The rocks the researchers studied contain characteristic layers of rusty-red, iron-rich jasper which formed as mineral-laden seawater spewed from hydrothermal vents. Scientists had thought the jaspers got their distinctive red colour from particles of iron oxide which, just like rust, form when iron is exposed to oxygen.
But how did this iron oxide form when Earth’s early oceans lacked oxygen? One theory is that photosynthesising cyanobacteria in the oceans produced the oxygen, and that it wasn’t until later, around 2.4 billion years ago, that this oxygen started to skyrocket in the atmosphere.
The new results change that assumption, however, “the story is completely different once you look closely enough,” said study co-author Professor Nick Tosca from Cambridge’s Department of Earth Sciences.
The researchers found that tiny, drab, particles of greenalite far outnumbered the iron oxide particles which give the jaspers their colour. The iron oxide was not an original feature, discounting the theory that they were formed by the activity of cyanobacteria.
“Our findings show that iron wasn’t oxidised in the oceans; instead, it combined with silica to form tiny crystals of greenalite,” said Tosca. “That means major oxygen producers, cyanobacteria, may have evolved later, potentially coinciding with the soar in atmospheric oxygen during the Great Oxygenation Event.”
Birger said that more experiments are needed to identify how greenalite might facilitate prebiotic chemistry, “but it was present in such vast quantities that, under the right conditions its surfaces could have synthesized an enormous number of RNA-type sequences, addressing a key question in origin of life research – where did all the RNA come from?”
Reference:
Rasmussen, B., Muhling, J., Tosca, N.J. 'Nanoparticulate apatite and greenalite in oldest, well-preserved hydrothermal vent precipitates.' Science Advances (2024). DOI: 10.1126/sciadv.adj4789
Researchers from the universities of Cambridge and Western Australia have uncovered the importance of hydrothermal vents, similar to underwater geysers, in supplying minerals that may have been a key ingredient in the emergence of early life.
MARUM − Zentrum für Marine Umweltwissenschaften, Universität BremenThe hydrothermal vent "Candelabra" in the Logatchev hydrothermal field on the Mid-Atlantic Ridge at a water depth of 3300 m
The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.
Ancient seafloor vents spewed tiny, life-giving minerals into Earth’s early oceans
Their study, published in Science Advances, examined 3.5-billion-year-old rocks from western Australia in previously unseen detail and identified large quantities of a mineral called greenalite, which is thought to have played a role in early biological processes. The researchers also found that the seafloor vents would have seeded the oceans with apatite, a mineral rich in the life-essential element phosphorus.
The earliest lifeforms we know of—single-celled microorganisms, or microbes—emerged around 3.7 billion years ago. Most of the rocks that contain traces of them and the environment they lived in have, however, been destroyed. Some of the only evidence we have of this pivotal time comes from an outcrop of sediments in the remote Australian outback.
The so-called Dresser Formation has been studied for years but, in the new study, researchers re-examined the rocks in closer detail, using high magnification electron microscopes to reveal tiny minerals that were essentially hidden in plain sight.
The greenalite particles they observed measured just a few hundred nanometres in size—so small that they would have been washed over thousands of kilometres, potentially finding their way into a range of environments where they may have kick-started otherwise unfavourable chemical reactions, such as those involved in building the first DNA and RNA molecules.
“We’ve found that hydrothermal vents supplied trillions upon trillions of tiny, highly-reactive greenalite particles, as well as large quantities of phosphorus,” said Professor Birger Rasmussen, lead author of the study from the University of Western Australia.
Rasmussen said scientists are still unsure as to the exact role of greenalite in building primitive cells, “but this mineral was in the right place at the right time, and also had the right size and crystal structure to promote the assembly of early cells.”
The rocks the researchers studied contain characteristic layers of rusty-red, iron-rich jasper which formed as mineral-laden seawater spewed from hydrothermal vents. Scientists had thought the jaspers got their distinctive red colour from particles of iron oxide which, just like rust, form when iron is exposed to oxygen.
But how did this iron oxide form when Earth’s early oceans lacked oxygen? One theory is that photosynthesising cyanobacteria in the oceans produced the oxygen, and that it wasn’t until later, around 2.4 billion years ago, that this oxygen started to skyrocket in the atmosphere.
The new results change that assumption, however, “the story is completely different once you look closely enough,” said study co-author Professor Nick Tosca from Cambridge’s Department of Earth Sciences.
The researchers found that tiny, drab, particles of greenalite far outnumbered the iron oxide particles which give the jaspers their colour. The iron oxide was not an original feature, discounting the theory that they were formed by the activity of cyanobacteria.
“Our findings show that iron wasn’t oxidised in the oceans; instead, it combined with silica to form tiny crystals of greenalite,” said Tosca. “That means major oxygen producers, cyanobacteria, may have evolved later, potentially coinciding with the soar in atmospheric oxygen during the Great Oxygenation Event.”
Birger said that more experiments are needed to identify how greenalite might facilitate prebiotic chemistry, “but it was present in such vast quantities that, under the right conditions its surfaces could have synthesized an enormous number of RNA-type sequences, addressing a key question in origin of life research – where did all the RNA come from?”
Reference:
Rasmussen, B., Muhling, J., Tosca, N.J. 'Nanoparticulate apatite and greenalite in oldest, well-preserved hydrothermal vent precipitates.' Science Advances (2024). DOI: 10.1126/sciadv.adj4789
Researchers from the universities of Cambridge and Western Australia have uncovered the importance of hydrothermal vents, similar to underwater geysers, in supplying minerals that may have been a key ingredient in the emergence of early life.
MARUM − Zentrum für Marine Umweltwissenschaften, Universität BremenThe hydrothermal vent "Candelabra" in the Logatchev hydrothermal field on the Mid-Atlantic Ridge at a water depth of 3300 m
The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.
Wed 24 Apr 17:30: Title to be confirmed
Abstract not available
- Speaker: Georgnia Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 12 Jun 17:30: Title to be confirmed
Abstract not available
- Speaker: Simon Haberle, Australian National University
- Wednesday 12 June 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Thu 07 Mar 11:30: TBC
Abstract not available
- Speaker: Dr Chun Ann Huang, Imperial College London
- Thursday 07 March 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.
Mon 05 Feb 18:00: Exploring the seafloor: the rock record of hydrothermal fluid circulation
Samples of seafloor rocks provide insights on processes at ridges and transform faults. I will present constraints on hydrothermal fluid circulation recorded in ultramafic rock samples from the Gakkel and Southwest Indian ridges. Petrographic and geochemical datasets for these samples indicate that fluid circulation occurred to temperatures >900C, which suggests that seawater is able to circulate to depths >20 km. Hydration to these depths implies that the oceanic lithosphere can be a significant reservoir of water from the time that it is created.
- Speaker: Jessica Warren - University of Delaware
- Monday 05 February 2024, 18:00-19:00
- Venue: Harker 1, Department of Earth Sciences, Downing Street.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Fri 01 Mar 16:00: High Performance Computing (HPC): what is it? how can I use it?
Computation is an important aspect of most scientific research these days. I will describe what is generally meant by “high performance” computing, and highlight different “workloads”, such as simulation, data processing and machine learning. I will also talk about locally available systems, national and international infrastructure. Finally, I will mention how to use the machines, whether that is with your own code, or using a well-known package, such as ASPECT or SPECFEM3D . I am also keen to hear what people are interested in doing, and happy to help them get started.
- Speaker: Chris Richardson
- Friday 01 March 2024, 16:00-17:00
- Venue: Tea Room, Old House.
- Series: Bullard Laboratories Tea Time Talks; organiser: David Al-Attar.
Tue 27 Feb 12:00: The TTG window and the formation of Earth’s earliest continental crust.
A large number of papers have been written on the processes responsible for the formation of the Earth’s earliest continental crust. These range from plume-based processes, through modern style plate tectonics all the way through to formation from bombardment as the solar system passed through galactic regions with high impact potential. Simultaneously, numerous papers have Attempted to identify the melting sources for the magnetic suites that define early continental crust, The Trondjhemite- Tonalite-Granodiorite suite. Despite the progress in these studies there remains considerable disagreement on sources and processes for TTG generation – in part because of a tendency to try and identify a single process and a single source for all the earliest fragments of continental crust. In this talk I will discuss a number of these issues and, in particular, whether or not a single source and single process is a geologically sensible approach, arguing instead that a number of different processes may operate and may independently form crust that is sufficiently thick and buoyant as to be preservable in the geological record.
- Speaker: Richard White, School of Earth and Environmental Sciences, University of St Andrews
- Tuesday 27 February 2024, 12:00-13:00
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Department of Earth Sciences Seminars (downtown); organiser: Dr Rachael Rhodes.
Ancient seafloor vents spewed tiny, life-giving minerals into Earth’s early oceans
Researchers from the universities of Western Australia and Cambridge have uncovered the importance of hydrothermal vents, similar to modern day black smokers, in supplying minerals that may have been a key ingredient in the emergence of early life. The study, published in Science Advances , examined 3.5-billion-year-old...
Thu 01 Feb 11:30: Transport and Settling of Buoyant Microplastics in Turbidity Currents
Although tens of millions of tons of plastic waste are released into the ocean each year, less than 300 kilotons remain on or near the ocean surface. This is particularly puzzling because more than half of plastics that are produced are buoyant in sea water. One mechanism that can result in buoyant plastic settling is the process of biofouling in which microbes and other organic material can accumulate on the plastics rendering them more dense. Less studied is the accumulation of inorganic material on the plastics. For example, clay has recently been shown to attach to plastics, particularly in the presence of surfactants. Here we report on laboratory experiments showing that plastic particles which are less dense than fresh water can settle due to the accumulation of glass spheres (“sand”) on their surface. This process is shown to occur dynamically as sand and plastic particles mix turbulently during the impulsive release of a turbidity current, which can carry some of the plastic particles to depth along with the settling sand. [This work reports on experiments performed by Woods Hole Oceanographic Institute (WHOI) Geophysical Fluid Dynamics (GFD) Fellow Quentin Kriaa during the WHOI GFD Summer Program 2023, co-supervised by Claudia Cenedese and Jim McElwaine.]
- Speaker: Professor Bruce Sutherland, Uni of Alberta
- Thursday 01 February 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.
Mon 29 Jan 18:00: Microbial Metabolic Innovation: A Constraint On The Early Animal Fossil Record?
For most of Earth’s history, soft tissues were rarely captured by the fossil record. Yet, for a brief window in the Ediacaran and early Palaeozoic, exceptional preservation of animal soft tissues was commonplace. Probing the genomes of a diverse array of microorganisms reveals metabolic innovations that substantially increase the decay rate of animal tissues, coincident with the decline of Ediacaran-style exceptional preservation.
- Speaker: Phil Vixseboxse - University of Cambridge
- Monday 29 January 2024, 18:00-19:00
- Venue: Harker 1, Department of Earth Sciences, Downing Street.
- Series: Sedgwick Club talks; organiser: Lucas Measures.
Fri 09 Feb 16:00: Title to be confirmed
Abstract not available
- Speaker: Esme Glastonbury-Southern
- Friday 09 February 2024, 16:00-17:00
- Venue: Tea Room, Old House.
- Series: Bullard Laboratories Tea Time Talks; organiser: David Al-Attar.
Fri 08 Mar 16:00: Extent and Implications of Dynamic Support Beneath Antartica and its Fringing Oceanic Basins
Abstract not available
- Speaker: Aisling Dunn
- Friday 08 March 2024, 16:00-17:00
- Venue: Tea Room, Old House.
- Series: Bullard Laboratories Tea Time Talks; organiser: David Al-Attar.
Tue 20 Feb 12:00: Rapid temperature fluctuations in the early Iceland plume revealed by olivine-spinel and melt thermometry
The generation of Large Igneous Provinces (LIPs) – huge outpourings of lavas associated with tectonic rifting – is a hotly debated topic with competing models variously invoking hot mantle plumes, insulative heating by supercontinents or edge driven convective instabilities. Mantle temperature and its temporal variation during LIP magmatism is key to distinguishing between these different models. Despite this, there are as yet no detailed stratigraphically constrained studies of mantle temperature through a LIP succession.
To address this, we have applied olivine-spinel and melt-only thermometry to constrain mantle potential temperature through a sequence of lavas from Co. Antrim, Northern Ireland, formed during the earliest expression of the North Atlantic Igneous Province. Mantle potential temperature derived from olivine-spinel and melt-only methods give consistent temperature ranges of 1374–1472°C and 1403–1521°C, respectively. Notable both temperature records indicate significant (100-120°C) variation in melting temperature over a relatively short stratigraphic during earlier forming magmas and much less variation in later formed magmas, suggesting initial instability or pulsing which stabilised with time.
Variability in melting temperature is mirrored by proxies for crustal and volcanic processes; Ni contents of olivine are elevated (
- Speaker: Elliot Carter, Trinity College Dublin
- Tuesday 20 February 2024, 12:00-13:00
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Department of Earth Sciences Seminars (downtown); organiser: Dr Rachael Rhodes.
Tue 13 Feb 12:00: Data-driven slow earthquake dynamics
Earthquakes are a destructive natural phenomenon with high societal costs and impact. A better understanding and characterisation of their underlying governing equations can help to better estimate the hazard associated with them. Slow slip events (SSEs) show many similarities with regular earthquakes but are characterised by a much shorter recurrence time (months/years instead of decades/millennia), offering us the possibility to study multiple cycles. Being able to model their dynamics can answer questions concerning the complexity of the frictional failure phenomenon at natural scale and its predictability. Studying slow earthquakes in nature and in the lab, I will show how a system of Stochastic Differential Equations can help us better characterise the seismic cycle, offering an alternative way to the classical two end members (purely deterministic or purely stochastic) used to describe seismicity. Blending the deterministic and stochastic approaches shows that friction is highly sensitive to small perturbations, suggesting that the macroscopic dynamics is influenced by small scale interactions. The so-called fast degrees of freedom active at the small spatio-temporal scales can be taken into account via a stochastic framework, while the underlying low-dimensional deterministic dynamics is used as a support to describe the evolution of the system.
- Speaker: Adriano Gualandi, Department of Earth Sciences
- Tuesday 13 February 2024, 12:00-13:00
- Venue: Department of Earth Sciences, Tilley Lecture Theatre.
- Series: Department of Earth Sciences Seminars (downtown); organiser: Dr Rachael Rhodes.
Tue 05 Mar 12:00: Paallavvik Island and the search for Earth's primitive water
For over a decade I have been working to answer the question ‘where did Earth source its water from?’ The answer may lie within igneous mantle plume rocks. This talk will focus on my 2021 expedition to Paallavvik Island, in search of geochemically anomalous picrite samples from the cliff sections of this uninhabited, polar-bear infested island, which sits off the east coast of Baffin Island.
- Speaker: Lydia Hallis, University of Glasgow
- Tuesday 05 March 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 31 Jan 16:00: Natural hazards in a warming world: exploring the big questions
Glacierized mountainous areas make up some of the most hazardous landscapes of our planet, and are undergoing profound changes under 21st century climatic warming. The answers to two fundamental questions are required in these areas: (i) what is the baseline hazard and risk, and (ii) are the hazard and risk likely to increase or decrease in coming decades. While these questions remain largely unanswered on a global scale, this presentation delves into the subject through a series of case studies of complex hazards in glacierized and high-mountain areas.
In this talk, I will consider both the gaps in our current knowledge, and how novel techniques and datasets help bridge these. In particular, I will discuss the two-way interactions between landslides and glaciers, improving summit ice volume estimates at glacierized volcanoes, and new optical feature tracking approaches to map slope deformation the scale of mountain ranges. The evolving hazard profile intersects with a growing population and rapidly developing infrastructure networks. As a result, a cross-disciplinary approach is essential to comprehensively analyze and mitigate risk. This talk highlights the significance of addressing these challenges and explores avenues for future research, in particular introducing the new Cambridge Complex and Multihazard Research Group (CoMHaz).
- Speaker: Max Van Wyk de Vries, University of Cambridge
- Wednesday 31 January 2024, 16:00-17:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Megan Holdt.
Wed 21 Feb 17:30: Microplastics from geologists' perspective Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Saija Saarni, University of Turku
- Wednesday 21 February 2024, 17:30-19:00
- Venue: Harker 2, Department of Earth Sciences, Downing Street.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 07 Feb 16:00: TBC
Abstract not available
- Speaker: Karen Lythgoe, University of Edinburgh
- Wednesday 07 February 2024, 16:00-17:00
- Venue: Wolfson Lecture Theatre.
- Series: Bullard Laboratories Wednesday Seminars; organiser: Adriano Gualandi.