Subscribe free to our newsletters via your
. 24/7 Space News .




EARLY EARTH
Ancient megavolcanoes killed half the world's species
by Staff Writers
Washington (AFP) March 21, 2013


New rock dating techniques have helped narrow the timeframe of a chain of massive volcanic eruptions that wiped out half the world's species 200 million years ago, a study said Thursday.

The result is the most precise date yet -- 201,564,000 years ago -- for the event known as the End-Triassic Extinction, or the fourth mass extinction, said the study in the journal Science.

The eruptions "had to be a hell of an event," said co-author Dennis Kent, a paleomagnetism expert at Columbia University's Lamont-Doherty Earth Observatory.

They may offer a historic parallel to the human-caused climate change happening today, by showing how sharp increases in carbon dioxide can outpace vulnerable species' ability to adapt, researchers said.

The new analysis winnows the estimated date from its previous range of up to three million years to 20,000 years at most, a blink of an eye in geological terms.

The eruptions caused an already hot Earth to become even more stifling, killing off plants and animals and making way for the age of the dinosaurs -- before they, too, were obliterated some 65 million years ago, possibly by another volcanic event combined with a devastating meteorite strike.

Volcanoes roiled the Earth in a time when most of the land mass was united in one big continent, spewing some 2.5 million cubic miles of lava that, over time, split the terrain and led to the creation of the Atlantic Ocean.

For the study, scientists analyzed rock samples from Nova Scotia, Morocco and outside New York City, all of which came from this once-united landmass known as the Central Atlantic Magmatic Province.

An analysis of the decay of uranium isotopes in the basalt, a type of rock left by the eruptions, offered researchers more precise dates.

The eruption in Morocco was the earliest, followed by Nova Scotia about 3,000 years later and New Jersey 13,000 years later.

Sediments that lie below that time hold fossils from the Triassic era. Above that layer, they disappear, the study said.

Some of the lost creatures include eel-like fish called conodonts, early crocodiles and tree lizards.

"In some ways, the End Triassic Extinction is analogous to today," said lead author Terrence Blackburn, who carried out the study while at the Massachusetts Institute of Technology but is now with the Carnegie Institution.

"It may have operated on a similar time scale. Much insight on the possible future impact of doubling atmospheric carbon dioxide on global temperatures, ocean acidity and life on earth may be gained by studying the geologic record."

.


Related Links
Explore The Early Earth at TerraDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








EARLY EARTH
An oxygen-poor 'boring' ocean challenged evolution of early life
Riverside CA (SPX) Mar 24, 2013
A research team led by biogeochemists at the University of California, Riverside has filled in a billion-year gap in our understanding of conditions in the early ocean during a critical time in the history of life on Earth. It is now well accepted that appreciable oxygen first accumulated in the atmosphere about 2.4 to 2.3 billion years ago. It is equally well accepted that the build-up of ... read more


EARLY EARTH
NASA's LRO Sees GRAIL's Explosive Farewell

Amazon's Bezos recovers Apollo 11 engines

Leaping Lunar Dust

Lunar Orbiter Image Recovery Project Seeks Public Support To Retrieve Apollo Era Moon Images

EARLY EARTH
Sun in the Way Will Affect Mars Missions in April

ChemCam data abundant at Planetary Conference

Los Alamos science sleuth on the trail of a Martian mystery

Curiosity Rover Exits 'Safe Mode'

EARLY EARTH
Lockheed Martin to Continue Providing Life Sciences Support To NASA

U.S. Astronomers Call on Congress to Support R and D Investments

NASA Voyager Status Update on Voyager 1 Location

Voyager 1 has entered a new region of space

EARLY EARTH
Shenzhou 10 - Next Stop: Jiuquan

China's fourth space launch center to be in use in two years

China to launch new manned spacecraft

Woman expected again to join next China crew roster

EARLY EARTH
New Space Station Crew Members to Launch and Dock the Same Day

ESA seeks innovators for orbiting laboratory

New ISS crew prepares for launch

Space crew returns to Earth from ISS

EARLY EARTH
Dragon capsule to spend extra day in space

Sea Launch and EchoStar Reach Preliminary Agreement for Launch Services

Estonia's student cubesat satellite is ready for the next Vega launch

Vega receives its upper stage as the next mission's two primary passengers land in French Guiana

EARLY EARTH
Astronomers Detect Water in Atmosphere of Distant Planet

Distant planetary system is a super-sized solar system

Water signature in distant planet shows clues to its formation

The Great Exoplanet Debate

EARLY EARTH
Record simulations conducted on Lawrence Livermore supercomputer

Breakthrough research shows chemical reaction in real time

Mainz scientists create new flexible mineral inspired by deep-sea sponges

NTU scientist develops a multi-purpose wonder material to tackle environmental challenges




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement