Israeli geologist finds oldest oceanic crust

Israeli geologist finds oldest oceanic crust

An Israeli geologist has discovered what he describes as the oldest oceanic crust in the world. The ancient crust that lies on bottom of Mediterranean Sea is believed to be 340 million years old. The finding was published in Nature Geoscience.

Roi Granot at the Ben-Gurion University of the Negev, Beersheba, studied the pattern of Earth’s magnetic field trapped in submerged rocks. He also measured the patch that resulted from breakdown of the supercontinent Pangaea in the Palaeozoic era.

The crust discovered recently was once thought to be a part of the southern Tethys Ocean that originated when the Panagea supercontinent broke slightly. The site today is called Herodotus Basin, which is the north eastern edge of the African plate that lies under the eastern Mediterranean Sea and is buried under over 10 kilometers of silt.

It could have been costly and time consuming thing to dig the sediments to measure how old the curst is. But Granot used Earth’s magnetic field to measure the time the curst belongs to. Earth’s magnetic field creates magnetic strips in the crust and each stripe can work as time indicator. They have formed over a period of millions of years.

Granot found 250 kilometers long strips in the Herodotus Basin. He then measured skewed patterns in the strips and calculated that the oceanic crust originated around 340 million years ago. This indicates that if the basin was once a part of Tethys Ocean it had formed about 100 million years before than previously believed.

“I was shocked. The picture was quite clear - I see oceanic crust! Since I had no one to share my new understanding, I had to walk back and forth in the airplane until [we] landed”, said Granot.

A report published in Business Insider informed, "Earth isn't the steadfast planet we assume it to be. Its continent-size slabs constantly move, buckle, and vanish beneath each other over the millennia, all while hardly leaving a trace."

The roughly 60,000-square-mile piece of crust has been hiding below the eastern Mediterranean Sea for about 340 million years. That means it's from right around when Earth's landmasses came together to form the supercontinent Pangea, which later separated into the continents we recognize today.

A crew towed three large sensors behind a boat, zigzagging across the sea during each trip to hunt for magnetic anomalies - the signatures of magnetic rocks locked in crust that was made by undersea volcanic ridges - buried deep beneath miles of ocean sediment.

According to a report in Nature World News by John Raphael, "The seafloor slab, described in a paper published in the journal Nature Geoscience, is about 340 million years old, approximately 150 million years older than the previous record holder located east of Japan. Dr. Granot believes that the 60,000 square mile piece of crust was a remnant of the Ancient Tethys Ocean, which existed long before the Atlantic and Indian Ocean."

Pangaea is known to be a supercontinent before newly forming ocean split it apart less than 300 million years ago. However, the discover of the 340 million years old oceanic crust suggests that the supercontinent started breaking apart before it was fully formed or that the section where the crust was found is already existing even before Pangaea arose.

Magnetic stripes is the striped pattern in mineral orientations formed when molten magma cools down, making the magnetic minerals within it to align themselves Earth's geomagnetic field. The flipping of the Earth's north and south magnetic poles forms the magnetic stripes for over millions of years.


User login



You May Have Missed...

Israeli geologist finds oldest oceanic crust
Tue, 08/16/2016 - 12:10

An Israeli geologist has discovered what he describes as the oldest oceanic crust in the world. The ancient crust that lies on bottom of...


Nigeria Update

Fresh Polio Cases lead to WHO Travel Restrictions on Pakistan and Syria
Tue, 05/06/2014 - 00:45

World Health Organization has slapped international travel restrictions on Pakistan, Cameroon...


Economy Watch

US Import Prices decline in April
Thu, 05/14/2015 - 01:13

For a straight 10th month, US import prices declined in April. The decline could be due to the...


Health Tonight

More than expected rise in US maternal death rate: Study
Tue, 08/09/2016 - 11:21

A rise has been witnessed in the US maternal death rate, women who die during or soon after...


UK News

How a Comet smells? Here’s a Perfume That Mimics the Smell
Wed, 06/29/2016 - 12:41

You may not be able to visit a comet in your life, but you can know how it smells. A British...


Pharmaceuticals

Aetna
Sat, 01/17/2015 - 06:04

Aetna inc., health care company, on Friday announced that it has signed a deal with Gilead...


US News

Facebook messages can now be officially sent to President Obama
Thu, 08/11/2016 - 10:46

In a highly noteworthy announcement made via a press release on Wednesday, the White House said...


Technology Tonight

HTC’s forthcoming Nexus Sailfish handset spotted on AnTuTu Benchmark
Fri, 08/12/2016 - 10:56

According to reports, Taiwanese handset maker HTC’s forthcoming Nexus handset for Google --...