Our directory of things of interest

University Directory

Appalachian bend explained

  • Written by  Olivia Edward
  • Published in Tectonics
The Appalachain mountains, USA The Appalachain mountains, USA Shutterstock
01 Sep
2014
A team of US scientists has explained why the Appalachian mountain chain has a curious bend in Pennsylvania and New York State

The Appalachians, which run for roughly 2,400 kilometres from Alabama to Newfoundland, were formed more than 300 million years ago when the North American and African continental plates collided.

The research team studied data collected by the Earthscope project, which uses GPS receivers and an array of portable seismometers to measure ground movement in northeastern USA. This was combined with data from the North American Gravity Database, allowing the researchers to determine the density of the rocks under and around the mountain range.

The results indicated the presence of a volcanic structure about 450 kilometres by 100 kilometres in size. The researchers were then able to use the data to model how the bend formed.

According to one of the study’s authors, Cindy Ebinger of the University of Rochester, scientists had previously known about the structure. ‘What we didn’t understand was the size of the structure or its implications for mountain-building processes,’ she said.

The computer model indicated that as the North American plate was pushed westward into the dense rock structure, it was folded and thrust upwards, creating the mountains. The shape of the structure caused the chain to shift east, forming the characteristic bend.

Related items

Geographical Week

Get the best of Geographical delivered straight to your inbox every Friday.

Subscribe to Geographical!

Adventure Canada

EDUCATION PARTNERS

Aberystwyth University University of Greenwich The University of Winchester

TRAVEL PARTNERS

Ponant

Silversea

Travel the Unknown

DOSSIERS

Like longer reads? Try our in-depth dossiers that provide a comprehensive view of each topic

  • National Clean Air Day
    For National Clean Air Day, Geographical brings together stories about air pollution and the kind of solutions needed to tackle it ...
    Hung out to dry
    Wetlands are vital storehouses of biodiversity and important bulwarks against the effects of climate change, while also providing livelihoods for mill...
    The green dragon awakens
    China has achieved remarkable economic success following the principle of developing first and cleaning up later. But now the country with the world's...
    The true cost of meat
    As one of the world’s biggest methane emitters, the meat industry has a lot more to concern itself with than merely dietary issues ...
    Mexico City: boom town
    Twenty years ago, Mexico City was considered the ultimate urban disaster. But, recent political and economic reforms have transformed it into a hub of...

MORE DOSSIERS

NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...

Wildlife

Celebrated author Professor Tim Birkhead provides a fascinating insight into…

Oceans

The world’s most biodiverse seagrass region – Indonesia’s Coral Triangle…

Oceans

Ocean conservation group urges world governments to step up action…

Climate

As climate conditions at the 100th meridian, the traditional United…

Climate

International shipping may be attempting to reduce its carbon footprint, but…

Geophoto

So much photographic theory is dedicated to image sharpness that…

Wildlife

Changing temperatures in East Africa are set to upset a delicate…

Climate

As the planet warms and tensions rise, Marco Magrini finds that…

Oceans

A deep-sea mission in the ocean around Bermuda confirms the…

Oceans

An oxygen-deprived ‘dead zone’ in the Arabian Sea is much…

Wildlife

Scientists working with new drone technology are hoping to reveal…

Oceans

A new virtual reality experience, ‘BBC Earth: Life in VR’,…

Nature

Faced with protecting a country more than 30 times the…

Oceans

As Chile’s president leaves office, the country designates large expanses…

Energy

More than two years after first being announced, the International…

Wildlife

The winner of the 2018 Whitley Gold Award is Pablo…

Polar

Celebrate World Penguin Day with this selection of penguin-related stories…

Geophoto

It takes a lot more than the latest research data…

Wildlife

NGOs shine a light on the underreporting of wildlife crime…

Wildlife

Pioneering laser photography is being used by scientists on the…