Short-term episodicity of Archaean plate tectonics

Mar 28, 2012

Plate tectonics, the dominant process shaping Earth as we know it today, may not have existed throughout Earth's history.

Indeed, the interior of our planet (the mantle) cools progressively, by perhaps 300 degrees Celsius over the past 3.0 billion years.

reveal that in Archaean times (4.0-2.5 billion years ago), the mantle was too hot to support stable, long-lived plate tectonics.

Rather, Jean-François Moyen and Jeroen van Hunen suggest that subduction -- a key component of plate tectonics, with cold, rigid plates sinking from the surface down into the -- was an episodic process, stopping and starting frequently.

Evidence for this episodicity is found in rocks from old geological units such as the Abitibi province of the Canadian Shield, where Moyen and van Hunen describe short, repeated, episodic bursts of subduction related lavas interlayered in non-subduction rocks.

They propose that started progressively on by more and more frequent, long-lived, and large-sized subduction events progressively evolving into the stable, large structures observed today.

Explore further: Atmospheric boundary layer exacerbated mega heat waves

More information: Jean-François Moyen, UMR 6524 CNRS and Université Jean-Monnet, 23 rue du Dr Michelon, 42023 Saint-Etienne, France., Durham DH1 3LE, UK; and Jeroen van Hunen Durham University. Geology. Posted online 26 March 2012; doi: 10.1130/G32894.1

Journal reference: Geology search and more info website

Provided by Geological Society of America

not rated yet
add to favorites email to friend print save as pdf

Related Stories

Plate tectonics may take a break

Jan 03, 2008

Plate tectonics, the geologic process responsible for creating the Earth’s continents, mountain ranges, and ocean basins, may be an on-again, off-again affair. Scientists have assumed that the shifting of crustal plates ...

Plate tectonics modelled realistically

Feb 23, 2012

Swiss scientists have for the first time succeeded in realistically simulating how an oceanic plate sinks of its own accord under an adjacent plate. At the same time they showed why only one of the plates ...

Plate tectonics coming of age

Nov 24, 2011

(PhysOrg.com) -- Plate tectonics in its current form is believed to have started one billion years ago. A study of two billion year old rocks from African gold mines has now shown that the same process of ...

Recommended for you

Atmospheric boundary layer exacerbated mega heat waves

2 hours ago

The extreme nature of the heat waves of 2003 in Western Europe and of 2010 in Russia and Eastern Europe even surprised scientists at the time. NWO Veni researcher Ryan Teuling from Wageningen University says ...

Magnitude-7.2 earthquake shakes Mexican capital

Apr 18, 2014

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

User comments : 0

More news stories