World’s Oldest Asteroid Crater Discovered In Western Australia

World's Oldest Asteroid Crater Discovered In Western Australia

Scientists at Curtin University have discovered that a crater in Yarrabubba, Western Australia, may be the world’s oldest, and that the asteroid’s landing 2.2 billion years ago may one of the reasons behind the end of the last Ice Age.

Despite the crater itself having been discovered in the outback in 1979, scientist had previously not tested the mineral deposits left behind to determine its age. The crater is not visible to the naked eye due to billions of years of erosion.

To determine when the asteroid hit the earth, scientists tested tiny zircon and monazite crystals found within the rocks whose properties will have changed upon the impact. Tiny amounts of uranium and iron deposits within the crystals enabled the scientists to figure out relatively accurately how long ago the asteroid struck.

Zircon crystal used to date the Yarrabubba impact. Curtin University

Zircon crystal used to date the Yarrabubba impact. Curtin University

The team of scientist are very excited about the age of the crater especially in the context of the Earth’s other events.

At this point, 2.2 billion years ago, the Earth’s surface was covered in ice, and it is now believed that the water vapour produced by this asteroid striking such a thick sheet of ice could be the reason behind a warming effect on the planet, perhaps even ending the Ice Age. Water vapor today is the most abundant greenhouse gas within the Earth’s atmosphere. Without greenhouse gasses, it is estimated that the average temperature of the planet would be -18 degrees Celsius, rather than the 15 degrees Celsius that currently stands. With additional greenhouse gasses entering the atmosphere, the average temperature of the planet is set to continue to rise.

Other theories have suggested that the carbon dioxide, another greenhouse gas, released from volcanic eruptions may be responsible.


Main Image: Barlangi Hill, part of the Yarrabubba crater. Graeme Churchyard, Flickr Creative Commons

 

Tectonic: New Zealand White Island Volcano Erupts

Tectonic: New Zealand White Island Volcano Erupts

New Zealand’s White Island Volcano, known locally as Whakaari, has erupted with a tragic blast leaving 34 people injured, 8 people missing and 6 confirmed dead. The eruption took place at approximately 2:00PM local time on December 9th 2019.

White Island’s volcano is New Zealand’s most active cone volcano, situated off the northeastern coast of New Zealand’s north island, attracting tourists, geologists and volcanologists from afar. The volcano has been releasing volcanic gasses constantly at least since it was first sighted by Captain James Cook 250 years ago in 1769.

In the past, the volcano has had eruptions of Lava, ash and pyroclastic flows, with the most recent significant eruption having been in 2016. In October 2019, the volcano was raised to a Volcanic Alert level 2, stating that there was increased volcanic activity and indicating that an eruption was more likely to occur.

Further seismic activity in the hours following the eruption included subsequent eruptions, and an earthquake at a magnitude of 5.3 in Gisborne, Northeastern New Zealand in the early hours of December 10th. The island is now on Volcanic Alert level 3, with GeoNet stating that the volcano is in minor eruption, but that the alert level could change without notice.

Of the confirmed fatalities, the injured and the missing people, all were either visiting the island as tourists or operating the tours. Pilot Productions extends it’s deepest sympathies and thoughts to all those affected by the eruption.

More information:

Study Guide: Volcanoes

Read: Captain Cook continues to inspire travel habits

Watch: Volcanoes – Ring of Fire

Watch: Globe Trekker – New Zealand 1

Watch: Globe Trekker – New Zealand 2

Main Image: White Island, New Zealand – Volcano, Thru MyShutter, Flickr Creative Commons

By Sofi Summers

Tectonic: Italian Volcanic Island Of Stromboli is Erupting

Tectonic: Italian Volcanic Island Of Stromboli is Erupting

A volcano has erupted on the Italian island of Stromboli, killing one hiker and injuring a second. Lava streams and rocks have been slowly making their way down the volcano’s slopes following the eruption yesterday afternoon.

WATCH ON DVD: Volcanoes & Extreme Landscapes

Stromboli has a population of around 500, and its volcano is very active with frequent minor eruptions, making for an adrenaline junky’s paradise. As many as 7000 tourists flock to the island every summer to take in its incredible natural beauty, challenging landscape and Italian Island charm.

READ: Fireworks Night: Trekking Mount Stromboli

Yesterday’s eruption is described as a ‘major eruption’ with two major explosive events occurring. Tourist’s and locals alike have described scenes of people fleeing hotels and restaurants and jumping into the sea in a state of panic.

READ: Study Guide: Volcanoes

The Aeolian Islands, where Stromboli is situated, are a volcanic archipelago in the Tyrrhenian Sea, and are listed by UNESCO as a World Heritage Site for providing “an outstanding record of volcanic island building and destruction, and ongoing volcanic phenomena”. Stromboli has been in a state of almost continuous eruption for the past 2000 years, its eruptions characterised as short and mild blasts of lava and rock and a slow and viscous flow of lava.

WATCH ON DVD: Globe Trekker – Cosica, Sicily & Sardinia where traveller Ian Wright visits the spitting summit of stromboli

 

Main Image: Flrnt, Stromboli, Flickr Creative Commons

By Sofi Pickering