Volcano cliffs can affect monitoring data, study finds

Published by  News Archive

On 21st Mar 2019

New research led by the University of East Anglia (UEA) reveals that sharp variations of the surface of volcanoes can affect data collected by monitoring equipment.

The surfaces of many volcanoes feature steep walls or cliffs. These are often part of calderas - large craters left by a previous collapse - but can also be caused by the volcano ‘rifting’ - or splitting - or sector collapse, when part of the side of the volcano slides away.

However, the effect of these variations in landscape has not previously been considered in studies of surface deformation in volcanic regions, even though they are a common feature.

In addition, monitoring equipment such as tiltmeters are usually placed on caldera rims as they are often more accessible, especially if the caldera is lake-filled. Tiltmeters measure the horizontal gradient of vertical displacement and can emphasise small variations that go unnoticed using other monitoring methods.

Now researchers from UEA, the US Geological Survey and University of Bristol have found that features such as cliffs can cause a reversal in the pattern of deformation, leading to misleading data being recorded by the tiltmeters. Their findings are published in Geophysical Research Letters.

The team studied Kilauea volcano in Hawaii, which erupted last April, resulting in a summit collapse that has reshaped the cliffs around the caldera. It now has near-vertical cliffs of up to 500 metres and terrace-like steps of 50-150 metres.

The researchers say these new structures may have an impact on tilt measured at the existing network of tiltmeters and have implications for any new monitoring equipment that is installed.

Lead researcher Dr Jessica Johnson, lecturer in geophysics at UEA’s School of Environmental Sciences, said: “Tilt measurements have played a significant role in the knowledge of volcanic processes on at least 40 volcanoes worldwide. Our analysis highlights the importance of considering surface features when assessing tilt measurements at active volcanoes, something that hasn’t generally been taken into account.

“While the inconsistent data at Kilauea cannot be completely explained by topography, it may have some influence. Following the most recent collapse at Kilauea this problem is likely to be even more pronounced and should be considered when new monitoring instruments are installed.”

The researchers investigated after finding anomalies in data collected from one of the tiltmeters on the caldera rim at Kilauea before the last eruption. They looked at whether this could be due to topography and found that the then 80 metre-high caldera wall caused data from one of the monitoring tiltmeters to rotate away from the true centre of deformation.

“These findings have implications for network design and ongoing monitoring,” said Dr Johnson, who visited Kilauea last July and previously spent two years on a research fellowship at the Hawaiian Volcano Observatory.

“They suggest that other tiltmeters around Kilauea and at volcanoes globally could be affected by caldera rims and other sharp variations in the landscape.”

Dr Johnson added: “If this this monitoring method is already being used there are things that can be done to fix the data stream. If new tilt monitors are being installed then we have got to be careful where they are deployed.”

Co-author Dr Juliet Biggs, from the University of Bristol, said: “Understanding what drives volcano deformation is critical for improving the interpretation of volcano monitoring data, and developing probabilisitic eruption forecasts. Tiltmeters are very sensitive to small changes in the volcanic conduit, but their measurements have been challenging to interpret.

“This study sheds new light on how these measurements are influenced by surface features such as steep cliffs, and will undoubtedly improve our ability to interpret the complex monitoring signals.”

‘A cautionary tale of topography and tilt from Kilauea Caldera’ Jessica H Johnson, Michael P Poland, Kyle R Anderson, and Juliet Biggs, is published in Geophysical Research Letters.

Latest News

A Turtle Dove on a branch
25 Jun 2022

Built infrastructure, hunting and climate change linked to huge migratory bird declines

Migratory birds are declining globally because of the way that humans have modified the landscape over recent decades, UEA research shows.

Read more >
An infant taking part in a research project at UEA.
24 Jun 2022

Babies and over 65s needed for UEA psychology research

From the very young to the somewhat older, psychology researchers at UEA are looking for participants to help with two studies.

Read more >
Destruction of forest
23 Jun 2022

Loss of nature is pushing nations toward sovereign credit downgrades and ‘bankruptcy’

The world's first biodiversity-adjusted sovereign credit ratings show how ecological destruction affects public finances – driving downgrades, debt crises and...

Read more >
Yelena Moskovich, Scarlett Brade, Charlie Higson
22 Jun 2022

Soviet-Ukrainian novelist and Fast Show comedian take centre stage at Noirwich Crime Writing Festival

The ninth Noirwich Crime Writing Festival returns in September, with a special line-up announced today (Wednesday 22 June) featuring an award-winning...

Read more >
Are you searching for something?
Yelena Moskovich, Scarlett Brade, Charlie Higson
22 Jun 2022

Soviet-Ukrainian novelist and Fast Show comedian take centre stage at Noirwich Crime Writing Festival

The ninth Noirwich Crime Writing Festival returns in September, with a special line-up announced today (Wednesday 22 June) featuring an award-winning...

Read more >
An older woman tries to get to sleep in bed.
22 Jun 2022

How sleep could help stroke patients make a better recovery

Researchers at UEA are launching a new study to see how sleep can help stroke recovery.

Read more >
17 Jun 2022

New report highlights the need for investment in NHS staff wellbeing

Poor mental health and wellbeing costs the NHS an estimated £12.1 billion a year, new research suggests.

Read more >
Lab research
15 Jun 2022

UEA receives funding boost for research projects

Projects which support early-stage translation of research to real impacts will benefit from new funding awards. 

Read more >
John-Mark Philo
15 Jun 2022

Academic awarded prestigious Future Leaders Fellowship

Dr John-Mark Philo, from UEA’s School of Literature, Drama and Creative Writing, has been awarded £1.2 million by UK Research and Innovation's Future Leaders...

Read more >
An oil painting of the Gloucester as it sank.
10 Jun 2022

Wreck of historic royal ship discovered off the English coast

The wreck of one of the most famous ships of the 17th century has been discovered off the coast of Norfolk in the UK, it can be revealed today.

Read more >