Featured Research

from universities, journals, and other organizations

When two parts of the Earth's crust break apart, this does not always cause massive volcanic eruptions

Date:
June 30, 2010
Source:
Imperial College London
Summary:
New research reveals that when two parts of the Earth's crust break apart, this does not always cause massive volcanic eruptions. The study explains why some parts of the world saw massive volcanic eruptions millions of years ago and others did not.

New research reveals that when two parts of the Earth's crust break apart, this does not always cause massive volcanic eruptions. The study, published June 16 in the journal Nature, explains why some parts of the world saw massive volcanic eruptions millions of years ago and others did not.

Related Articles


The Earth's crust is broken into plates that are in constant motion over timescales of millions of years. Plates occasionally collide and fuse, or they can break apart to form new ones. When the latter plates break apart, a plume of hot rock can rise from deep within the Earth's interior, which can cause massive volcanic activity on the surface.

When the present-day continent of North America broke apart from what is now Europe, 54 million years ago, this caused massive volcanic activity along the rift between the two. Prior to today's study, scientists had thought that such activity always occurred along the rifts that form when continents break apart.

However, today's research shows that comparatively little volcanic activity occurred when the present-day sub-continent of India broke away from what is now the Seychelles, 63 million years ago.

Researchers had previously believed that the temperature of the mantle beneath a plate was the key to determining the level of volcanic activity where a rift occurred. The new study reveals that in addition, the prior history of a rift also strongly influences whether or not volcanic activity will occur along it.

In the case of the break-up of America from Europe, massive volcanic activity occurred along the rift because a previous geological event had thinned the plate, according to today's study. This provided a focal point where the mantle underneath the plate could rapidly melt, forming magma that erupted easily through the thinned plate and onto the surface, in massive outbursts of volcanic activity.

In comparison, when India broke away from the Seychelles very little volcanic activity occurred along the North Indian Ocean floor, because the region had experienced volcanic activity in a neighbouring area called the Gop Rift 6 million years earlier. This exhausted the supply of magma and cooled the mantle, so that when a rift occurred, very little magma was left to erupt.

Dr Jenny Collier, co-author from the Department of Earth Science and Engineering at Imperial College London, says: "Mass extinctions, the formation of new continents and global climate change are some of the effects that can happen when plates break apart and cause super volcanic eruptions. Excitingly, our study is helping us to see more clearly some of the factors that cause the events that have helped to shape the Earth over millions of years."

The team reached their conclusions after carrying out deep sea surveys of the North Indian Ocean to determine the type of rock below the ocean floor. They discovered only small amounts of basalt rock, which is an indicator of earlier volcanic activity .The team also used new computer models that they had developed to simulate what had happened along the ocean floor in the lead up to India and the Seychelles splitting apart.

Dr John Armitage, lead author of the paper from the Department of Earth Science and Engineering at Imperial College London, adds: "Our study is helping us to see that the history of the rift is really important for determining the level of volcanic activity when plates break apart. We now know that this rift history is just as important as mantle temperature in controlling the level of volcanic activity on the Earth's surface."

In the future, the team hope to further explore the ocean floor off the coast of South America where that continent split from Africa millions of years ago to determine the level of ancient volcanic activity in the region.

This work was partly funded by the UK Natural Environment Research Council.


Story Source:

The above story is based on materials provided by Imperial College London. Note: Materials may be edited for content and length.


Journal Reference:

  1. Armitage et al. The importance of rift history for volcanic margin formation. Nature, 2010; 465 (7300): 913 DOI: 10.1038/nature09063

Cite This Page:

Imperial College London. "When two parts of the Earth's crust break apart, this does not always cause massive volcanic eruptions." ScienceDaily. ScienceDaily, 30 June 2010. <www.sciencedaily.com/releases/2010/06/100616133321.htm>.
Imperial College London. (2010, June 30). When two parts of the Earth's crust break apart, this does not always cause massive volcanic eruptions. ScienceDaily. Retrieved March 1, 2015 from www.sciencedaily.com/releases/2010/06/100616133321.htm
Imperial College London. "When two parts of the Earth's crust break apart, this does not always cause massive volcanic eruptions." ScienceDaily. www.sciencedaily.com/releases/2010/06/100616133321.htm (accessed March 1, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Sunday, March 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Whale-Watching Scientists Spot Baby Orca

Whale-Watching Scientists Spot Baby Orca

AP (Feb. 28, 2015) Researchers following endangered killer whales spotted a baby orca off the coast of Washington state, the third birth documented this winter but still leaving the population dangerously low. (Feb. 28) Video provided by AP
Powered by NewsLook.com
Bridge Collapses Due to Flooding in Bolivia

Bridge Collapses Due to Flooding in Bolivia

Reuters - News Video Online (Feb. 28, 2015) Heavy rain and flooding sweep through parts of Bolivia causing damage and leaves more than 2,000 people homeless. Sophia Soo reports. Video provided by Reuters
Powered by NewsLook.com
Death Toll from Afghan Avalanches Tops 200

Death Toll from Afghan Avalanches Tops 200

AFP (Feb. 27, 2015) More than 200 people have been killed in a series of avalanches triggered by heavy snowfall in Afghanistan. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
France, Philippines Call for Agreement on Climate Change

France, Philippines Call for Agreement on Climate Change

Reuters - News Video Online (Feb. 27, 2015) The presidents of France and the Philippines issue a joint appeal for a binding agreement on climate change. Katie Sargent reports. Video provided by Reuters
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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