Featured Research

from universities, journals, and other organizations

Chaitén Volcano In Southern Chile: Historic Volcanic Eruptions Significantly Underestimated, Ash Fallout Analysis Shows

Date:
May 10, 2009
Source:
University of Oxford
Summary:
A study into ash fallout from the biggest volcanic eruption in almost 20 years has shown that the impact of past eruptions is likely to have been significantly underestimated as so much of the evidence quickly disappears.

Ash and steam rising from the Chaiten lava dome, shortly after a small earthquake.
Credit: Oxford University

A study into ash fallout from the biggest volcanic eruption in almost 20 years has shown that the impact of past eruptions is likely to have been significantly underestimated as so much of the evidence quickly disappears, Oxford University scientists report.

The study focuses on the Chaitén volcano in southern Chile that began to erupt explosively on 2 May 2008. For six days afterwards the volcano pumped huge volumes of ash high into the atmosphere before its activity began to decline to a low intensity eruption still going on today. 

With emergency funding from the UK’s Natural Environment Research Council, a team of scientists from the University of Oxford was quickly dispatched to map out the distribution of ash from the eruption and to study its impacts on the local environment, in collaboration with Argentinian scientists. 

A first report of their findings is published in the Journal of Geophysical Research.

‘The area around a volcano immediately after an eruption is like a crime scene where the evidence can quickly be destroyed by the elements,’ said Professor David Pyle of Oxford University’s Department of Earth Sciences. ‘Ash deposited on land will rapidly be removed by rain or wind, while ash deposited out to sea is only accessible by collecting core samples of the sea-floor sediment. This makes it extremely difficult for volcanologists to accurately reconstruct a past eruption from the available evidence and say how much fine ash was deposited, and over what area, during an eruption.’

The team’s work on Chaitén has shown that the several millimetres thickness of ash deposited across Argentina have been lost from wide areas – of at least 50,000 square kilometers – in only nine months. A geologist attempting to map the region affected by ash fallout now would significantly underestimate the size of the area affected, and as a result would underestimate the size of the eruption and the amount of ash erupted.

‘By using satellite imagery to guide us, we were able to map the ash fallout across Argentina to a thickness of less than one tenth of a millimetre,’ said Sebastian Watt, a PhD student in Oxford’s Department of Earth Sciences, who led the team. ‘We collected samples from over 220 sites across an area of 100,000 square kilometres and with these field data and samples we were able to make the first scientific assessment of the size and impact of the eruption.’  

The Chaitén eruption had immediate social and economic impacts across Patagonia (southern Chile and Argentina), with more than 5,000 people evacuated from settlements up to 75 km from the volcano, and extensive ash deposition leading to regional disruption of agriculture and aviation. The volcano was not routinely monitored, and there was no recognised warning before the eruption started. 

Sebastian Watt said: ‘Chaitén is still erupting right now, although it is currently in a less explosive phase. Our previous work has shown that eruptions from this volcano have the potential to be much larger in size making careful monitoring of the present eruption a priority.’


Story Source:

The above story is based on materials provided by University of Oxford. Note: Materials may be edited for content and length.


Cite This Page:

University of Oxford. "Chaitén Volcano In Southern Chile: Historic Volcanic Eruptions Significantly Underestimated, Ash Fallout Analysis Shows." ScienceDaily. ScienceDaily, 10 May 2009. <www.sciencedaily.com/releases/2009/05/090507195208.htm>.
University of Oxford. (2009, May 10). Chaitén Volcano In Southern Chile: Historic Volcanic Eruptions Significantly Underestimated, Ash Fallout Analysis Shows. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2009/05/090507195208.htm
University of Oxford. "Chaitén Volcano In Southern Chile: Historic Volcanic Eruptions Significantly Underestimated, Ash Fallout Analysis Shows." ScienceDaily. www.sciencedaily.com/releases/2009/05/090507195208.htm (accessed September 2, 2014).

Share This




More Earth & Climate News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Thousands of Fish Dead in Mexico Lake

Raw: Thousands of Fish Dead in Mexico Lake

AP (Sep. 2, 2014) — Over 53 tons of rotting fish have been removed from Lake Cajititlan in western Jalisco state. Authorities say that the thousands of fish did not die of natural causes. (Sep. 2) Video provided by AP
Powered by NewsLook.com
Raw: Iceland Volcano Spewing Smoke

Raw: Iceland Volcano Spewing Smoke

AP (Sep. 2, 2014) — The alert warning for the area surrounding Iceland's Bardarbunga volcano was kept at orange on Tuesday, indicating increased unrest with greater potential for an eruption. Smoke is spewing from the volcano, and lava is spouting nearby. (Sept. 2) Video provided by AP
Powered by NewsLook.com
U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) — The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Sharks Off the Menu and on the Tourist Trail in Palau

Sharks Off the Menu and on the Tourist Trail in Palau

AFP (Sep. 2, 2014) — Tourists in Palau clamour to dive with sharks thanks to a pioneering conservation initiative -- as the island nation plans to completely ban commercial fishing in its vast ocean territory. 01:15 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins