Throughout history, our planet has encountered numerous celestial bodies, some of which are quite large. However, uninterrupted geological activity is gradually erasing the traces of these collisions. The largest impact crater confirmed to date was the 250 to 300 kilometers diameter Vredefort Crater in South Africa. This massive crater even surpasses the famous Chicxulub crater, which was implicated in the extinction of non-avian dinosaurs.

Although Wilkes Black Crater in Antarctica stretches for 500 kilometers, confirmation of the impact’s source remains unclear. However, recent research by Australian scientists points to a potential new champion in the field of impact craters: the Deniliquin structure in southeast Australia, whose diameter over 500 kilometers.

According to the researchers, it was this catastrophic event that could have caused the ancient mass extinction during the Ordovician-Silurian period.

Examination of impact craters

For decades, scientists have relied mainly on “external” signs of impact craters, such as:

• round depressions,
• central elevators,
• concentric rings.

Unfortunately, these features are subject to erosion, sedimentary burial, and other forms of degradation. In the last few years, based on new techniques analysis of certain mineralsIt was formed as a result of monumental influences. These methods make it possible to estimate the size and age of primary structures, although they are almost completely destroyed.

In the late 20th century, Professor Andrew Glickson of the University of New South Wales discovered mineral signatures in the Murray River Basin that indicated the presence of an ancient and imposing structure with a central uplift of impact zones. On this basis, a new analysis has been made using carefully collected geophysical data for the period 2015-2020. This extensive study confirmed previous findings and made it possible to estimate the diameter of the structure in an unprecedented way. 520 kilometers.

The mineral distribution revealed a central fold that plunges 30 kilometers below the surface and rises 10 kilometers above the adjacent mantle layers. Around this core are concentric rings broken by fissures through which magma flows. These characteristics coincide with those of large impact craters. And yet, these conclusions were made on the basis of surface analysis of minerals. Verification requires drilling and exploration of deeper layers.

If the Deniliquin structure turns out to be a truly ancient crater, its formation predates the continent itself. Scientists hypothesize that its origin is linked to the Ordovician-Silurian extinction that occurred approximately. 450 million years agoWhile Australia was part of the Gondwana supercontinent.

It can be assumed that this event may be the cause. global climate disasterled to the extinction of many previously existing species. But geologists remain cautious, suggesting Deniliquin may be even older. Only future and more detailed research will reveal the full story of this monumental discovery.