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Department of Earth Sciences

 

Cambridge Zero student survey on climate change and sustainability

The Cambridge Green Challenge News - Fri, 30/07/2021 - 12:07

Cambridge Zero want to hear your views! All students at the University of Cambridge, graduates and undergraduates alike, are invited to fill out this 6-minute survey (full link here: https://forms.office.com/r/1RFt0ZeH8K ) so we can better understand your needs and wants within climate change education and sustainability...

Award-winning sustainability projects from across the University

The Cambridge Green Challenge News - Thu, 29/07/2021 - 09:58

As part of the University’s Green Impact scheme , more experienced teams select a particular sustainability topic that they would like to focus on. This year we’re excited to be sharing three outstanding Excellence projects to help inspire your department, building or College to take sustainability action. Waste to Art and...

The gloves are off – recycling is in safe hands in West Cambridge departments

The Cambridge Green Challenge News - Wed, 28/07/2021 - 10:21

On a recent hot Thursday afternoon, a truck left the University’s West Cambridge site laden with two large but unremarkable pallet bags. Unremarkable they may have seemed, but they carried thousands upon thousands of purple gloves and marked the start of a new recycling trial here at the University. The picture above shows...

The gloves are off – recycling is in safe hands in West Cambridge departments

The Cambridge Green Challenge News - Wed, 28/07/2021 - 10:21

On a recent hot Thursday afternoon, a truck left the University’s West Cambridge site laden with two large but unremarkable pallet bags. Unremarkable they may have seemed, but they carried thousands upon thousands of purple gloves and marked the start of a new recycling trial here at the University. This was the first load...

July travel and transport update

The Cambridge Green Challenge News - Wed, 28/07/2021 - 08:50

Last month the transport team concluded Let’s Talk Transport! Over the course of the campaign over 200 people took part in webinars and focus groups to help us better understand the challenges staff and students face to travelling sustainably. The information you shared with us demonstrated a lot of interest in improving...

Wildflower corridors could be the future for Cambridge Colleges

The Cambridge Green Challenge News - Tue, 27/07/2021 - 16:02

Amongst the turbulence of the pandemic, thousands found much needed solace in the natural world. A survey conducted by Natural England found that 38% of respondents felt that nature and wildlife had become more important for their wellbeing since the first lockdown. This is perhaps unsurprising given the breadth of...

Meet our new Assistant Energy Manager

The Cambridge Green Challenge News - Tue, 27/07/2021 - 15:50

Max Shone, Assistant Energy Manager What does your position involve? Central to my role will be the continuous improvement of our utility metering network throughout the estate. Also, I have a background in the Water Industry and there are plans to put this to use in any future tendering process for water supply agreements...

Making room for nature at Cambridge University Library

The Cambridge Green Challenge News - Tue, 27/07/2021 - 14:56

Being wrapped in silence is a familiar feeling when entering a library but with the UK’s first lockdown in 2020, silence fell like never before in the Cambridge University Library. Reading rooms emptied, staff were furloughed or working from home, and just a few individuals would enter each day to perform essential checks...

Earth's interior is swallowing up more carbon than thought

They found that the carbon drawn into Earth’s interior at subduction zones - where tectonic plates collide and dive into Earth’s interior - tends to stay locked away at depth, rather than resurfacing in the form of volcanic emissions.

Their findings, published in Nature Communications, suggest that only about a third of the carbon recycled beneath volcanic chains returns to the surface via recycling, in contrast to previous theories that what goes down mostly comes back up.

One of the solutions to tackle climate change is to find ways to reduce the amount of CO2 in Earth’s atmosphere. By studying how carbon behaves in the deep Earth, which houses the majority of our planet’s carbon, scientists can better understand the entire lifecycle of carbon on Earth, and how it flows between the atmosphere, oceans and life at the surface.

The best-understood parts of the carbon cycle are at or near Earth’s surface, but deep carbon stores play a key role in maintaining the habitability of our planet by regulating atmospheric CO2 levels. “We currently have a relatively good understanding of the surface reservoirs of carbon and the fluxes between them, but know much less about Earth’s interior carbon stores, which cycle carbon over millions of years,” said lead author Stefan Farsang, who conducted the research while a PhD student at Cambridge's Department of Earth Sciences.

There are a number of ways for carbon to be released back to the atmosphere (as CO2) but there is only one path in which it can return to the Earth’s interior: via plate subduction. Here, surface carbon, for instance in the form of seashells and micro-organisms which have locked atmospheric CO2 into their shells, is channelled into Earth’s interior. Scientists had thought that much of this carbon was then returned to the atmosphere as CO2 via emissions from volcanoes. But the new study reveals that chemical reactions taking place in rocks swallowed up at subduction zones trap carbon and send it deeper into Earth’s interior - stopping some of it coming back to Earth’s surface.

The team conducted a series of experiments at the European Synchrotron Radiation Facility, “The ESRF have world-leading facilities and the expertise that we needed to get our results,” said co-author Simon Redfern, Dean of the College of Science at NTU Singapore, “The facility can measure very low concentrations of these metals at the high pressure and temperature conditions of interest to us.” To replicate the high pressures and temperatures of subductions zones, they used a heated ‘diamond anvil’, in which extreme pressures are achieved by pressing two tiny diamond anvils against the sample.

The work supports growing evidence that carbonate rocks, which have the same chemical makeup as chalk, become less calcium-rich and more magnesium-rich when channelled deeper into the mantle. This chemical transformation makes carbonate less soluble – meaning it doesn’t get drawn into the fluids that supply volcanoes. Instead, the majority of the carbonate sinks deeper into the mantle where it may eventually become diamond.

“There is still a lot of research to be done in this field,” said Farsang. “In the future, we aim to refine our estimates by studying carbonate solubility in a wider temperature, pressure range and in several fluid compositions.”

The findings are also important for understanding the role of carbonate formation in our climate system more generally. “Our results show that these minerals are very stable and can certainly lock up CO2 from the atmosphere into solid mineral forms that could result in negative emissions,” said Redfern. The team have been looking into the use of similar methods for carbon capture, which moves atmospheric CO2 into storage in rocks and the oceans.

“These results will also help us understand better ways to lock carbon into the solid Earth, out of the atmosphere. If we can accelerate this process faster than nature handles it, it could prove a route to help solve the climate crisis,” said Redfern.

 

Reference:
Farsang, S., Louvel, M., Zhao, C. et al. Deep carbon cycle constrained by carbonate solubility. Nature Communications (2021). DOI: 10.1038/s41467-021-24533-7

Adapted from a news release by the ESRF

Scientists from Cambridge University and NTU Singapore have found that slow-motion collisions of tectonic plates drag more carbon into Earth’s interior than previously thought.

We currently have a relatively good understanding of the surface reservoirs of carbon and the fluxes between them, but know much less about Earth’s interior carbon stores, which cycle carbon over millions of yearsStefan FarsangNASA Goddard Space Flight CenterAlaska’s Pavlof Volcano: NASA’s View from Space


The text in this work is licensed under a Creative Commons Attribution 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 – as here, 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.

YesLicense type: Attribution
Categories: News

Earth's interior is swallowing up more carbon than thought

Research News - Mon, 26/07/2021 - 10:59

They found that the carbon drawn into Earth’s interior at subduction zones - where tectonic plates collide and dive into Earth’s interior - tends to stay locked away at depth, rather than resurfacing in the form of volcanic emissions.

Their findings, published in Nature Communications, suggest that only about a third of the carbon recycled beneath volcanic chains returns to the surface via recycling, in contrast to previous theories that what goes down mostly comes back up.

One of the solutions to tackle climate change is to find ways to reduce the amount of CO2 in Earth’s atmosphere. By studying how carbon behaves in the deep Earth, which houses the majority of our planet’s carbon, scientists can better understand the entire lifecycle of carbon on Earth, and how it flows between the atmosphere, oceans and life at the surface.

The best-understood parts of the carbon cycle are at or near Earth’s surface, but deep carbon stores play a key role in maintaining the habitability of our planet by regulating atmospheric CO2 levels. “We currently have a relatively good understanding of the surface reservoirs of carbon and the fluxes between them, but know much less about Earth’s interior carbon stores, which cycle carbon over millions of years,” said lead author Stefan Farsang, who conducted the research while a PhD student at Cambridge's Department of Earth Sciences.

There are a number of ways for carbon to be released back to the atmosphere (as CO2) but there is only one path in which it can return to the Earth’s interior: via plate subduction. Here, surface carbon, for instance in the form of seashells and micro-organisms which have locked atmospheric CO2 into their shells, is channelled into Earth’s interior. Scientists had thought that much of this carbon was then returned to the atmosphere as CO2 via emissions from volcanoes. But the new study reveals that chemical reactions taking place in rocks swallowed up at subduction zones trap carbon and send it deeper into Earth’s interior - stopping some of it coming back to Earth’s surface.

The team conducted a series of experiments at the European Synchrotron Radiation Facility, “The ESRF have world-leading facilities and the expertise that we needed to get our results,” said co-author Simon Redfern, Dean of the College of Science at NTU Singapore, “The facility can measure very low concentrations of these metals at the high pressure and temperature conditions of interest to us.” To replicate the high pressures and temperatures of subductions zones, they used a heated ‘diamond anvil’, in which extreme pressures are achieved by pressing two tiny diamond anvils against the sample.

The work supports growing evidence that carbonate rocks, which have the same chemical makeup as chalk, become less calcium-rich and more magnesium-rich when channelled deeper into the mantle. This chemical transformation makes carbonate less soluble – meaning it doesn’t get drawn into the fluids that supply volcanoes. Instead, the majority of the carbonate sinks deeper into the mantle where it may eventually become diamond.

“There is still a lot of research to be done in this field,” said Farsang. “In the future, we aim to refine our estimates by studying carbonate solubility in a wider temperature, pressure range and in several fluid compositions.”

The findings are also important for understanding the role of carbonate formation in our climate system more generally. “Our results show that these minerals are very stable and can certainly lock up CO2 from the atmosphere into solid mineral forms that could result in negative emissions,” said Redfern. The team have been looking into the use of similar methods for carbon capture, which moves atmospheric CO2 into storage in rocks and the oceans.

“These results will also help us understand better ways to lock carbon into the solid Earth, out of the atmosphere. If we can accelerate this process faster than nature handles it, it could prove a route to help solve the climate crisis,” said Redfern.

 

Reference:
Farsang, S., Louvel, M., Zhao, C. et al. Deep carbon cycle constrained by carbonate solubility. Nature Communications (2021). DOI: 10.1038/s41467-021-24533-7

Adapted from a news release by the ESRF

Scientists from Cambridge University and NTU Singapore have found that slow-motion collisions of tectonic plates drag more carbon into Earth’s interior than previously thought.

We currently have a relatively good understanding of the surface reservoirs of carbon and the fluxes between them, but know much less about Earth’s interior carbon stores, which cycle carbon over millions of yearsStefan FarsangNASA Goddard Space Flight CenterAlaska’s Pavlof Volcano: NASA’s View from Space


The text in this work is licensed under a Creative Commons Attribution 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 – as here, 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.

YesLicense type: Attribution

Plate subduction locks away more carbon than thought

Earth Sciences news - Wed, 21/07/2021 - 14:30

Scientists from Cambridge University and NTU Singapore have found that carbon drawn into Earth’s interior by plate subduction tends to stay locked away at depth, rather than resurfacing in the form of volcanic emissions, as previously thought. Their findings, published in Nature Communications , suggest that only about a...

Categories: Recent news and blogs

Spot on! Support biodiversity with our summer campaign

The Cambridge Green Challenge News - Tue, 29/06/2021 - 13:12

Here at the University we believe that conserving biodiversity is inherently the right thing to do, we need to rebuild nature and give biodiversity a helping hand. Join our summer ‘Spot on!’ campaign to find out how our wildlife sightings can support a nature-friendly estate and future. The campaign is packed full of talks...

Behind the scenes: wildflowers, green rooves and biodiversity progress at Cambridge

The Cambridge Green Challenge News - Tue, 29/06/2021 - 10:33

In October last year the University launched its 10-year vision for biodiversity and accompanying Biodiversity Action Plan. Since then, our grounds teams have been hard at work making sure our targets are turning into action across the estate. Wildflower and improved pond areas have been a huge hit with the local wildlife...

Save Our Cycles - addressing bike theft in Cambridge

The Cambridge Green Challenge News - Mon, 28/06/2021 - 22:03

Cycle theft is the most reported crime in Cambridge and Camcycle has joined with Cambridge City Council, Cambridgeshire Police and other local organisations to raise awareness of the issue and ensure cyclists across Cambridgeshire take reasonable steps to secure their bikes. The University is happy to be endorsing this...

Contribute to an international cycling safety project

The Cambridge Green Challenge News - Mon, 28/06/2021 - 21:45

As the University wraps up its Let’s Talk Transport campaign , we wanted to share a new initiative focusing on cycling safety. Bike-Barometer 2020-2021 is a collaborative, international project led by the University of Valencia, with the University of Southampton leading on UK data collection. There are clearly many...

BREEAM Environmental Rating of ‘Excellent’ confirmed for a complex lab refurbishment

The Cambridge Green Challenge News - Mon, 28/06/2021 - 21:05

The University has just completed the refurbishment of the Gleeson Building in Tennis Court Road. The building dates from 1988 and has now been brought fully up to date, providing modern laboratory space and state-of-the-art instrumentation for the MRC Toxicology Unit . Work involved extensive renewal of mechanical and...

Rock crystals from the deep give microscopic clues to earthquake ground movements

The stresses resulting from these defects – which are small enough to disrupt the atomic building blocks of a crystal – can transform how hot rocks beneath Earth’s crust move and in turn transfer stress back to Earth’s surface, starting the countdown to the next earthquake. 

The new study, published in Nature Communications, is the first to map out the crystal defects and surrounding force fields in detail. “They’re so tiny that we’ve only been able to observe them with the latest microscopy techniques,” said lead author Dr David Wallis from Cambridge's Department of Earth Sciences, “But it’s clear that they can significantly influence how deep rocks move, and even govern when and where the next earthquake will happen.”

By understanding how these crystal defects influence rocks in the Earth’s upper mantle, scientists can better interpret measurements of ground motions following earthquakes, which give vital information on where stress is building up - and in turn where future earthquakes may occur.

Earthquakes happen when pieces of Earth’s crust suddenly slip past each other along fault lines, releasing stored-up energy which propagates through the Earth and causes it to shake. This movement is generally a response to the build-up of tectonic forces in the Earth’s crust, causing the surface to buckle and eventually rupture in the form of an earthquake.

Their work reveals that the way Earth’s surface settles after an earthquake, and stores stress prior to a repeat event, can ultimately be traced to tiny defects in rock crystals from the deep.

“If you can understand how fast these deep rocks can flow, and how long it will take to transfer stress between different areas across a fault zone, then we might be able to get better predictions of when and where the next earthquake will strike,” said Wallis.

The team subjected olivine crystals – the most common component of the upper mantle -- to a range of pressures and temperatures in order to replicate conditions of up to 100 km beneath Earth’s surface, where the rocks are so hot (roughly 1250oC) they move like syrup.

Wallis likens their experiments to a blacksmith working with hot metal – at the highest temperatures, their samples were glowing white-hot and pliable.

They observed the distorted crystal structures using a high-resolution form of electron microscopy, called electron backscatter diffraction, which Wallis has pioneered on geological materials.

Their results shed light on how hot rocks in the upper mantle can mysteriously morph from flowing almost like syrup immediately after an earthquake to becoming thick and sluggish as time passes.

This change in thickness -- or viscosity – transfers stress back to the cold and brittle rocks in the crust above, where it builds up – until the next earthquake strikes.

The reason for this switch in behaviour has remained an open question, “We’ve known that microscale processes are a key factor controlling earthquakes for a while, but it’s been difficult to observe these tiny features in enough detail,” said Wallis. “Thanks to a state-of-the-art microscopy technique, we’ve been able to look into the crystal framework of hot, deep rocks and track down how important these miniscule defects really are”.

Wallis and co-authors show that irregularities in the crystals become increasingly tangled over time; jostling for space due to their competing force fields – and it’s this process that causes the rocks to become more viscous.

Until now it had been thought that this increase in viscosity was because of the competing push and pull of crystals against each other, rather than being caused by microscopic defects and their stress fields inside the crystals themselves.

The team hope to apply their work to improving seismic hazard maps, which are often used in tectonically active areas like southern California to estimate where the next earthquake will occur. Current models, which are usually based on where earthquakes have struck in the past, and where stress must therefore be building up, only take into account the more immediate changes across a fault zone and do not consider gradual stress changes in rocks flowing deep within the Earth.

Working with colleagues at Utrecht University, Wallis also plans to apply their new lab constraints to models of ground movements following the hazardous 2004 earthquake which struck Indonesia, and the 2011 Japan quake – both of which triggered tsunamis and lead to the loss of tens of thousands of lives.

 

Reference:
David Wallis et al. 'Dislocation interactions in olivine control postseismic creep of the upper mantle.' Nature Communications (2021). DOI: 10.1038/s41467-021-23633-8

Microscopic imperfections in rock crystals deep beneath Earth’s surface play a deciding factor in how the ground slowly moves and resets in the aftermath of major earthquakes, says new research involving the University of Cambridge.

James St. JohnChunks of exotic green rocks from the mantle erupted from the San Carlos Volcanic Field, Arizona


The text in this work is licensed under a Creative Commons Attribution 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 – as here, 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.

YesLicense type: Attribution
Categories: News

Rock crystals from the deep give microscopic clues to earthquake ground movements

Research News - Thu, 24/06/2021 - 11:27

The stresses resulting from these defects – which are small enough to disrupt the atomic building blocks of a crystal – can transform how hot rocks beneath Earth’s crust move and in turn transfer stress back to Earth’s surface, starting the countdown to the next earthquake. 

The new study, published in Nature Communications, is the first to map out the crystal defects and surrounding force fields in detail. “They’re so tiny that we’ve only been able to observe them with the latest microscopy techniques,” said lead author Dr David Wallis from Cambridge's Department of Earth Sciences, “But it’s clear that they can significantly influence how deep rocks move, and even govern when and where the next earthquake will happen.”

By understanding how these crystal defects influence rocks in the Earth’s upper mantle, scientists can better interpret measurements of ground motions following earthquakes, which give vital information on where stress is building up - and in turn where future earthquakes may occur.

Earthquakes happen when pieces of Earth’s crust suddenly slip past each other along fault lines, releasing stored-up energy which propagates through the Earth and causes it to shake. This movement is generally a response to the build-up of tectonic forces in the Earth’s crust, causing the surface to buckle and eventually rupture in the form of an earthquake.

Their work reveals that the way Earth’s surface settles after an earthquake, and stores stress prior to a repeat event, can ultimately be traced to tiny defects in rock crystals from the deep.

“If you can understand how fast these deep rocks can flow, and how long it will take to transfer stress between different areas across a fault zone, then we might be able to get better predictions of when and where the next earthquake will strike,” said Wallis.

The team subjected olivine crystals – the most common component of the upper mantle -- to a range of pressures and temperatures in order to replicate conditions of up to 100 km beneath Earth’s surface, where the rocks are so hot (roughly 1250oC) they move like syrup.

Wallis likens their experiments to a blacksmith working with hot metal – at the highest temperatures, their samples were glowing white-hot and pliable.

They observed the distorted crystal structures using a high-resolution form of electron microscopy, called electron backscatter diffraction, which Wallis has pioneered on geological materials.

Their results shed light on how hot rocks in the upper mantle can mysteriously morph from flowing almost like syrup immediately after an earthquake to becoming thick and sluggish as time passes.

This change in thickness -- or viscosity – transfers stress back to the cold and brittle rocks in the crust above, where it builds up – until the next earthquake strikes.

The reason for this switch in behaviour has remained an open question, “We’ve known that microscale processes are a key factor controlling earthquakes for a while, but it’s been difficult to observe these tiny features in enough detail,” said Wallis. “Thanks to a state-of-the-art microscopy technique, we’ve been able to look into the crystal framework of hot, deep rocks and track down how important these miniscule defects really are”.

Wallis and co-authors show that irregularities in the crystals become increasingly tangled over time; jostling for space due to their competing force fields – and it’s this process that causes the rocks to become more viscous.

Until now it had been thought that this increase in viscosity was because of the competing push and pull of crystals against each other, rather than being caused by microscopic defects and their stress fields inside the crystals themselves.

The team hope to apply their work to improving seismic hazard maps, which are often used in tectonically active areas like southern California to estimate where the next earthquake will occur. Current models, which are usually based on where earthquakes have struck in the past, and where stress must therefore be building up, only take into account the more immediate changes across a fault zone and do not consider gradual stress changes in rocks flowing deep within the Earth.

Working with colleagues at Utrecht University, Wallis also plans to apply their new lab constraints to models of ground movements following the hazardous 2004 earthquake which struck Indonesia, and the 2011 Japan quake – both of which triggered tsunamis and lead to the loss of tens of thousands of lives.

 

Reference:
David Wallis et al. 'Dislocation interactions in olivine control postseismic creep of the upper mantle.' Nature Communications (2021). DOI: 10.1038/s41467-021-23633-8

Microscopic imperfections in rock crystals deep beneath Earth’s surface play a deciding factor in how the ground slowly moves and resets in the aftermath of major earthquakes, says new research involving the University of Cambridge.

James St. JohnChunks of exotic green rocks from the mantle erupted from the San Carlos Volcanic Field, Arizona


The text in this work is licensed under a Creative Commons Attribution 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 – as here, 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.

YesLicense type: Attribution

Dr Sasha Turchyn recognised as 2021 R. Berner Lectureship winner

Earth Sciences news - Wed, 23/06/2021 - 16:42

Many congratulations to Dr Sasha Turchyn who is the recipient of the 2021 R. Berner Lectureship . The Lectureship, which will be presented at the Goldschmidt 2021 conference, is awarded to scientists who show an 'exceptional ability to define globally important biogeochemical processes, develop new understanding, and...

Categories: Recent news and blogs

Rock crystals from the deep give microscopic clues to earthquake ground movements

Earth Sciences news - Wed, 23/06/2021 - 15:07

Microscopic imperfections in rock crystals deep beneath Earth’s surface play a deciding factor in how the ground slowly moves and resets in the aftermath of major earthquakes, says new research involving the University of Cambridge. The stresses resulting from these defects – which are small enough to disrupt the atomic...

Categories: Recent news and blogs