News tagged with volcanic eruptions

Giant impact near India -- not Mexico -- may have doomed dinosaurs

A mysterious basin off the coast of India could be the largest, multi-ringed impact crater the world has ever seen. And if a new study is right, it may have been responsible for killing the dinosaurs off 65 ...

Space & Earth / Earth Sciences

created Oct 15, 2009 | popularity 4.8 / 5 (42) | comments 15

Researchers find smoking gun of world's biggest extinction

About 250 million years about 95 per cent of life was wiped out in the sea and 70 per cent on land. Researchers at the University of Calgary believe they have discovered evidence to support massive volcanic ...

Space & Earth / Earth Sciences

created Jan 23, 2011 | popularity 4.7 / 5 (38) | comments 36 | with audio podcast

Expanding Spot on Venus Puzzles Astronomers

(PhysOrg.com) -- The expanding spot discovered on Venus last month may not have garnered as much attention as the meteor impact with Jupiter, but its cause is certainly more puzzling. ...

Space & Earth / Space Exploration

created Aug 04, 2009 | popularity 4.3 / 5 (31) | comments 7 weblog

Previously Unknown Volcanic Eruption Helped Trigger Cold Decade

(PhysOrg.com) -- A team of chemists from the U.S. and France has found compelling evidence of a previously undocumented large volcanic eruption that occurred exactly 200 years ago, in 1809.

Space & Earth / Earth Sciences

created Oct 29, 2009 | popularity 4.3 / 5 (27) | comments 9

Studies agree on a 1 meter rise in sea levels

New research from several international research groups, including the Niels Bohr Institute at the University of Copenhagen provides independent consensus that IPCC predictions of less than a half a meter ...

Space & Earth / Earth Sciences

created Apr 13, 2010 | popularity 3.5 / 5 (33) | comments 32 | with audio podcast

Possible trigger for volcanic 'super-eruptions' found

The "super-eruption" of a major volcanic system occurs about every 100,000 years and is considered one of the most catastrophic natural events on Earth, yet scientists have long been unsure about what triggers ...

Space & Earth / Earth Sciences

created Oct 12, 2011 | popularity 4.9 / 5 (22) | comments 20 | with audio podcast

Earth's massive extinction: The story gets worse

Scientists have uncovered a lot about the Earth's greatest extinction event that took place 250 million years ago when rapid climate change wiped out nearly all marine species and a majority of those on land. ...

Space & Earth / Earth Sciences

created Jan 05, 2012 | popularity 4 / 5 (25) | comments 36 | with audio podcast

Paleoecologists suggest mass extinction due to huge methane release

(PhysOrg.com) -- Micha Ruhl and colleagues from the University of Copenhagen's Nordic Center for Earth Evolution have published a paper in Science where they contend that the mass extinction that occurred at the ...

Space & Earth / Earth Sciences

created Jul 22, 2011 | popularity 4.4 / 5 (21) | comments 32 | with audio podcast report

Experts reaffirm asteroid impact caused mass extinction 65 million years ago (w/ Video)

(PhysOrg.com) -- Responding to challenges to the hypothesis that an asteroid impact caused a mass extinction on Earth 65 million years, a panel of 41 scientists re-analyzed data and provided new evidence, ...

Space & Earth / Earth Sciences

created Mar 04, 2010 | popularity 4.4 / 5 (20) | comments 4 | with audio podcast

Ancient volcano may have caused mass extinction

A previously unknown giant volcanic eruption that led to global mass extinction 260million years ago has been uncovered by scientists at the University of Leeds.

Space & Earth / Earth Sciences

created May 28, 2009 | popularity 4.4 / 5 (20) | comments 0

Scientists offer new theory for largest known mass extinction

The largest mass extinction in the history of the earth could have been triggered off by giant salt lakes, whose emissions of halogenated gases changed the atmospheric composition so dramatically that vegetation ...

Space & Earth / Earth Sciences

created Mar 30, 2009 | popularity 4 / 5 (21) | comments 5

Team explains how dinosaurs rose to prominence

A shade more than 200 million years ago, the Earth looked far different than it does today. Most land on the planet was consolidated into one continent called Pangea. There was no Atlantic Ocean, and the rulers ...

Space & Earth / Earth Sciences

created Mar 22, 2010 | popularity 4.7 / 5 (17) | comments 9 | with audio podcast

Study suggests dinosaurs killed off by more than one asteroid

(PhysOrg.com) -- Dinosaurs, along with over half of other species, became extinct at the end of the Cretaceous period about 65.5 million years ago, and many scientists believe this was due to a single impact ...

Space & Earth / Earth Sciences

created Aug 31, 2010 | popularity 4.2 / 5 (19) | comments 24 | with audio podcast report

Supervolcano eruption -- in Sumatra -- deforested India 73,000 years ago

A new study provides "incontrovertible evidence" that the volcanic super-eruption of Toba on the island of Sumatra about 73,000 years ago deforested much of central India, some 3,000 miles from the epicenter, ...

Space & Earth / Earth Sciences

created Nov 23, 2009 | popularity 4.5 / 5 (17) | comments 3

NOAA study suggests aerosols might be inhibiting global warming

(PhysOrg.com) -- A new study led by the U.S, National Oceanic and Atmospheric Administration (NOAA) shows that tiny particles that make their way all the way up into the stratosphere may be offsetting a global ...

Space & Earth / Earth Sciences

created Jul 22, 2011 | popularity 4.4 / 5 (17) | comments 28 | with audio podcast report

Volcano

A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot, molten rock, ash, and gases to escape from below the surface. Volcanic activity involving the extrusion of rock tends to form mountains or features like mountains over a period of time. The word volcano is derived from the name of Vulcano island off Sicily. In turn, it was named after Vulcan, the Roman god of fire.

Volcanoes are generally found where tectonic plates are diverging or converging. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are usually not created where two tectonic plates slide past one another. Volcanoes can also form where there is stretching and thinning of the Earth's crust (called "non-hotspot intraplate volcanism"), such as in the African Rift Valley, the Wells Gray-Clearwater volcanic field and the Rio Grande Rift in North America and the European Rhine Graben with its Eifel volcanoes.

Volcanoes can be caused by mantle plumes. These so-called hotspots, for example at Hawaii, can occur far from plate boundaries. Hotspot volcanoes are also found elsewhere in the solar system, especially on rocky planets and moons.

For more information about Volcano, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.