Atlas Mountains in Morocco are buoyed up by superhot rock

Date:

Share post:

The Atlas Mountains defy the standard model for mountain structure in which high topography must have deep roots for support, according to a new study from Earth scientists at USC.

Atlas Mountains in Morocco are buoyed up by superhot rock
Atlas Mountains [Credit: Christoph Hormann/Views of Earth]

In a new model, the researchers show that the mountains are floating on a layer of hot molten rock that flows beneath the region’s lithosphere, perhaps all the way from the volcanic Canary Islands, just offshore northwestern Africa.

“Our findings confirm that mountain structures and their formation are far more complex than previously believed,” said lead author Meghan Miller, assistant professor of Earth sciences at the USC Dornsife College of Letters, Arts and Sciences.

The study, coauthored by Thorsten Becker, professor of Earth sciences at USC Dornsife, was published by Geology on Jan. 1, 2014 and highlighted by Nature Geoscience.

A well-established model for the Earth’s lithosphere suggests that the height of the Earth’s crust must be supported by a commensurate depth, much like how a tall iceberg doesn’t simply float on the surface of the water but instead rests on a large submerged mass of ice. This property is known as “istostacy.”

“The Atlas Mountains are at present out of balance, likely due to a confluence of existing lithospheric strength anomalies and deep mantle dynamics,” Becker said.

Atlas Mountains in Morocco are buoyed up by superhot rock
This is a profile depicting the height and depth of the Atlas Mountains. The blue bars indicate the boundary between the crust and the superhot rock below, about 15 km shallower than predicted by previous models [Credit: Meghan Miller and Thorsten Becker]

Miller and Becker used seismometers to measure the thickness of the lithosphere – that is, the Earth’s rigid outermost layer – beneath the Altas Mountains in Morocco. By analyzing 67 distant seismic events with 15 seismometers, the team was able to use the Earth’s vibrations to “see” into the deep subsurface.

They found that the crust beneath the Atlas Mountains, which rise to an elevation of more than 4,000 meters, reaches a depth of only about 35 km – about 15 km shy of what the traditional model predicts.

“This study shows that deformation can be observed through the entire lithosphere and contributes to mountain building even far away from plate boundaries” Miller said.

Miller’s lab is currently conducting further research into the timing and effects of the mountain building on other geological processes.

Source: University of Southern California [January 02, 2014]

ADVERTISEMENT

spot_img

Related articles

A Greek showcase in modern Italy

Some 900 kilometers west of Athens, on the southern coast of Sicily, lies a fascinating place steeped in...

Experts meet to discuss Maya calendar, debunk end-of-world stories

As the clock winds down to Dec. 21, experts on the Mayan calendar have been racing to convince...

1,500 year old livestock stable found in Israel

A structure that was apparently used as a livestock stable in the Byzantine period was recently revealed in...

Jain basadi at Talakad to be excavated

The ancient site of Talakad continues to beckon archaeologists and explorers hoping to uncover the world buried in...

Team recovers ‘most complete Michigan mastodon skeleton in many decades’ from Thumb site

The most complete ice age mastodon skeleton found in Michigan since the 1940s was recovered this month from...

Origin of Scandinavian gorges finally revealed

The deep gorges which cut across Scandinavian landscapes may have been carved by rivers flowing under ancient glaciers,...

Ancient tectonic activity was trigger for ice ages

For hundreds of millions of years, Earth's climate has remained on a fairly even keel, with some dramatic...

3,000-year-old artefacts unearthed in central Vietnam

Antiques from 1000 BC have been unearthed at a mountainous site in the central province of Quang Ngai....