Massive asteroid impact crater in Falklands linked with Great Dying mass extinction

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Credit: worldatlas.com

Something new for geologists to get their teeth into.

The Falkland Islands may be home to one of the world’s largest craters, reports the IB Times. A new analysis has revealed it has many characteristics of an asteroid impact and may date back to the ‘Great Dying’ extinction event.

About 200 similar large craters have been discovered so far on Earth but there are many other examples of them on other planets including on Venus, Mercury and Mars.

The Falkland Islands structure, which is described in detail in the journal Terra Nova, has a diameter measuring approximately 250 kilometres (150 miles). If it turns out to be an impact crater, this size would make it one of Earth’s largest – comparable to the famous Chicxulub crater discovered in the Yucatan Peninsula in Mexico nearly four decades ago.

Gravity and magnetism

In this research, the scientists have documented the geophysical features of a large basin situated on the Falkland (Malvinas) Plateau, to the northwest of West Falkland Island.

They have analysed marine seismic-reflection profiles of the area, and conducted gravity and magnetic surveys. Their investigations suggest that they are confronted with a large basin with traits consistent with those of impact craters caused by collisions with asteroids.

In particular, the researchers note a gravity anomaly, characterised by a decrease in the strength of Earth’s gravity over the site. This negative anomaly is surrounded by a ring-shaped positive gravity anomaly. These features are very similar to the one seen at the Chicxulub impact structure.

In contrast, there is an important increase in the strength of Earth’s magnetism in the basin’s vicinity – another characteristic of other large impact craters.

Continued here.