Featured Research

from universities, journals, and other organizations

Surprise: Geologists Find Glaciers Can Suppress Volcanic Eruptions

Date:
December 9, 1998
Source:
University Of North Carolina At Chapel Hill
Summary:
Scientists have known for decades that large erupting volcanoes such as Mt. St. Helens in Washington and Mt. Pinatubo in the Philippines can alter climate by spewing smoke, gases and ash into the atmosphere. Now new evidence indicates that the opposite also occurs - that environmental change can trigger volcanic eruptions. Over the past 800,000 years, a new study shows, glaciers prompted eruptions after they retreated north.

CHAPEL HILL - Scientists have known for decades that large erupting volcanoes such as Mt. St. Helens in Washington and Mt. Pinatubo in the Philippines can alter climate by spewing smoke, gases and ash into the atmosphere.

Related Articles


Now new evidence indicates that the opposite also occurs - that environmental change can trigger volcanic eruptions. Over the past 800,000 years, a new study shows, glaciers prompted eruptions after they retreated north.

Dr. Allen F. Glazner, professor of geological sciences at the University of North Carolina at Chapel Hill, reported results of field and laboratory research at the American Geophysical Union's fall meeting in San Francisco Tuesday (Dec. 8).

"When we looked at almost the last million years of geologic activity in eastern California, we found that volcanoes tended to erupt between glacial cycles," Glazner said. "When the glaciers were present, the volcanoes were pretty much subdued. When the glaciers retreated, volcanoes became much more active."

Earlier research had shown a similar pattern around islands and along coastlines, but the new study is the first to show it happens far inland as well, he said.

How glaciers suppress eruptions is not known, Glazner said.

"One possibility is that all the extra weight of the glacial ice holds the magma, or molten rock, in place," he said. "Then when the ice melts and the water evaporates, less weight on the Earth's crust triggers volcanoes to erupt."

The UNC-CH scientist, who has been studying California geology for many years, said the newest work involved three years of chipping samples from volcanoes east of the Sierra Nevada and both dating the lava specimens and analyzing them chemically. He and his colleagues also analyzed previously gathered data.

"We are interested in the connection between a natural process - volcanism - and climate, in part because we want to know how much of the recent global warming is due to people burning fossil fuels and how much is just natural," Glazner said. "This past year, for example, has been the warmest on record, and some people are concerned about it."

Others involved in the study were Drs. Curtis R. Manley of geological sciences and Steve Marron of statistics, both at UNC-CH, Lang Farmer of the University of Colorado and Stuart Rojstaczer of Duke University.

The National Science Foundation and the Geothermal Program Office of the China Lake Naval Weapons Center supported the research. The U.S. Navy funds Glazner's work because the China Lake center lies near several young volcanoes that the federal government taps for geothermal energy. It also tests missiles there.

"Data indicate a lot of volcanic activity since the glaciers last retreated about 10,000 years ago, and recent increasing earthquake activity raises the possibility of eruptions in the Mammoth Lakes area of eastern California in the not-too-distant future," Glazner said. "Many people have moved there for skiing, mountain biking and the dry climate."

In the past million years in the Northern Hemisphere, glaciers have moved south about 10 times, he said.


Story Source:

The above story is based on materials provided by University Of North Carolina At Chapel Hill. Note: Materials may be edited for content and length.


Cite This Page:

University Of North Carolina At Chapel Hill. "Surprise: Geologists Find Glaciers Can Suppress Volcanic Eruptions." ScienceDaily. ScienceDaily, 9 December 1998. <www.sciencedaily.com/releases/1998/12/981209080734.htm>.
University Of North Carolina At Chapel Hill. (1998, December 9). Surprise: Geologists Find Glaciers Can Suppress Volcanic Eruptions. ScienceDaily. Retrieved March 6, 2015 from www.sciencedaily.com/releases/1998/12/981209080734.htm
University Of North Carolina At Chapel Hill. "Surprise: Geologists Find Glaciers Can Suppress Volcanic Eruptions." ScienceDaily. www.sciencedaily.com/releases/1998/12/981209080734.htm (accessed March 6, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Friday, March 6, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Late Winter Storm Wreaks Havoc Across Eastern US

Late Winter Storm Wreaks Havoc Across Eastern US

AP (Mar. 5, 2015) — A strong cold front moving across the eastern U.S. has dumped deep snow in some regions, creating hazardous conditions from Kentucky to New England. (March 5) Video provided by AP
Powered by NewsLook.com
Keurig Co-Founder Says Company Has A Waste Problem

Keurig Co-Founder Says Company Has A Waste Problem

Newsy (Mar. 5, 2015) — Keurig co-founder John Sylvan told The Atlantic he doesn&apos;t even own a Keurig because they&apos;re too expensive and produce too much waste. Video provided by Newsy
Powered by NewsLook.com
Raw: Tourists Visit Rare Grey Whales in Mexico

Raw: Tourists Visit Rare Grey Whales in Mexico

AP (Mar. 4, 2015) — Once nearly extinct, grey whales now migrate in their thousands to Mexico&apos;s Vizcaino reserve in Baja California, in search of warmer waters to mate and give birth. Tourists flock to the reserve to see the whales, measuring up to 49 feet long. (March 4) Video provided by AP
Powered by NewsLook.com
Raw: Injured Miners Treated After Blast

Raw: Injured Miners Treated After Blast

AP (Mar. 4, 2015) — An explosion ripped through a coal mine before dawn Wednesday in war-torn eastern Ukraine, killing at least one miner, officials said. Graphic video of injured miners being treated in a Donetsk hospital. (March 4) Video provided by AP
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