Mountains not as stable, Wits researchers prove

2013-10-15 11:37
Mountains are not as stable as previously thought, researchers have found. (Duncan Alfreds, News24)

Mountains are not as stable as previously thought, researchers have found. (Duncan Alfreds, News24)

Multimedia   ·   User Galleries   ·   News in Pictures Send us your pictures  ·  Send us your stories

kalahari.com

  • Environment
    This volume of "The New Encyclopedia of Southern Culture" surveys the dynamic environmental forces... Now R886.00
    buy now
Johannesburg - New evidence by South African researchers has shown that mountains are not as stable as previously thought.

Lightning strikes causing rocks to explode have for the first time been shown to play a huge role in shaping mountain landscapes in southern Africa, debunking previous assumptions that angular rock formations were necessarily caused by cold temperatures

Professors Jasper Knight and Stefan Grab from the School of Geography, Archaeology and Environmental Studies at Wits University used a compass to prove that lightning is responsible for some of the angular rock formations in the Drakensburg.

"A compass needle always points to magnetic north. But when you pass a compass over a land's surface, if the minerals in the rock have a strong enough magnetic field, the compass will read the magnetic field of the rock, which corresponds to when it was formed," said Knight.

"In the Drakensburg, there are a lot of basalt rocks which contain a lot of magnetic minerals, so they've got a very strong magnetic signal."

Slow change

He added that readings showed a dramatic shift in the polarity of rocks where lighting was known to have struck. This indicates that the phenomenon had the ability to melt the rock and which took on the polarity of the Earth when it cooled again.

"The energy of the lightning hitting the land's surface can, for a short time, partially melt the rock and when the rock cools down again, it takes on the magnetic imprint of today's magnetic field, not the magnetic field of millions of years ago when the rock was originally formed," said Knight.

Because of the movement of continents, magnetic north for the newly formed rock will be different from that of the older rock around it.

The researchers challenge the assumption that mountains are passive and that change occurs very slowly over long periods of time.

"Many people have considered mountains to be pretty passive agents, just sitting there to be affected by cold climates over these long periods of time.

"This evidence suggests that that is completely wrong. African mountain landscapes sometimes evolve very quickly and very dramatically over short periods of time. These are actually very sensitive environments and we need to know more about them," said Knight.

The research was published in the Geomorphology journal and may hold important clues for the people living in the valleys below mountain ranges.
- SAPA
Read more on:    environment
NEXT ON NEWS24X
SHARE:

Read News24’s Comments Policy

24.com publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
15 comments
Add your comment
Comment 0 characters remaining
 

Inside News24

 
/Dewani Trial
 

Red Bull Lionheart trail run - not for the fainthearted!

Entries are open, so what are you waiting for?

 
 

Where were you when you last felt alive?

Adventure holidays for your bucket list
Top 10 water sports to try before you die
6 impressive camping tips
LOL! The 8 stages of marathon running

Jobs in Cape Town [change area]

Property [change area]

Travel - Look, Book, Go!

Magical Massinga

Spend 5 nights at the gorgeous Massinga Beach Lodge in Mozambique and only pay for 4 from R13 220 per person sharing. Includes return flights, accommodation, transfers and romantic turndown. Book now!

Kalahari.com - shop online today

Save up to R1000 on Hisense smartphones!

View the large range of Hisense smartphones. Buy today and save up to R1000!

Deal of the week!

Save R1200 on the Samsung 48” smart full HD LED television now only R8799. Buy now!

Toys 4 for the price of 3

Buy 4 toys and get the cheapest FREE! Offer valid while stocks last. Shop now!

Mind blowing prices – As seen on TV

Get mind blowing prices on 1000’s of products! Shop now.

Save 20% on Nivea beauty products!

Buy any two Nivea beauty products and save 20%. Offer valid while stocks last. Shop now!

OLX Free Classifieds [change area]

Samsung Galaxy s4

Mobile, Cell Phones in South Africa, Western Cape, Cape Town. Date October 24

Best bargain in big bay

Real Estate, Houses - Apartments for Sale in South Africa, Western Cape, Cape Town. Date October 25

VW Golf 6, 1.6 Trendline (Excellent condition)

Vehicles, Cars in South Africa, Western Cape, Cape Town. Date October 25

Horoscopes
Aquarius
Aquarius

There is an easy social flow and the need to blend in, yet you may not feel entirely comfortable. Something beneath the surface...read more

There are new stories on the homepage. Click here to see them.
 
English
Afrikaans
isiZulu

Hello 

Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.


Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire 24.com network.

Settings

Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.








Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.