Scientists recently conducted a new study that revealed how the largest known asteroid impact structure on Earth is buried in Southeast Australia. Dr. Andrew Glickson a geologist and Visiting Fellow of the School of Archaeology and Anthropology at Australian National University and his colleague Tony Yeates published the new study in the journal Tectonophysics.
During the research, the scientists studied a region that they believed to must have experienced asteroid impact in the past. Based on the outcome of the research, the team of researchers concluded that the largest known asteroid impact structure was buried deep beneath the surface of Earth in Southern New South Wales.
How the researchers discovered the largest known Asteroid impact structure
The researchers studied the surface beneath a region in Southern New South Wales and discovered the Deniliquin structure spanning up to 520 kilometers in diameter. Keep in mind that the Vredefort impact structure in South Africa retains the largest known asteroid impact as it has a size of about 300 km wide. However, the latest discovery which is yet to be tested by drilling has dethroned the Vredefort impact. Scientists revealed that the early Earth is bombarded by asteroids.
However, the impact of these bombardments has been concealed by Earth’s surface over the years. Researchers revealed that erosion could have triggered wind and water to wear out the land materials over time. Note that whenever asteroids hit the surface of a celestial body, it creates a crater with a raised core. Scientists revealed that the center of the crater often serves as the major characteristic of massive asteroid impact structures.
However, due to changes that occur on the Earth’s surface, the crater might disappear in thousands or millions of years. This disappearance makes it challenging to spot any crater. The visible craters can also be buried by sediments over time. Scientists revealed that they might likely vanish due to subduction.
During the subduction, tectonic plates often collide and slide below each other and move into Earth’s mantle layer. However, the latest geophysical discoveries are created by asteroids and they may have spanned up to tens of kilometers wide. The new findings are also helping us to understand how our home planet evolved.
What Scientists founded during the discovery
Ejecta which are materials pumped out of the crater during the asteroid impact was also spotted during the research. The team believed that the oldest layers of this ejecta could be seen in sediments during the early terrains around the Earth. The newest study revealed that Earth and other planets within the Solar System were exposed to massive asteroid bombardments until about 3.2 billion years ago.
Some massive impacts are related to massive extinction occurrence. Astronomers revealed that Australia and its predecessor continent, Gondwana have remained the target of several asteroid impacts in the past. They have collectively received up to 38 verified and 43 potential impact structures.
These structures range from small craters to large and entirely buried structures. Tony Yeates conducted research between 1995 and 2000 to reveal that patterns underneath the Murray Basin in New South Wales might have huge buried impact structures. During an updated geophysical study between 2015 and 2020, scientists discovered the existence of about 520 km in diameter. This structure possesses a seismically-like dome at its center.
Conclusion
Scientists recently discovered that the largest known asteroid impact structure is buried in Southeast Australia. The researchers hope that a new study on the early Paleozoic Earth will unveil more about the Deniliquin impact structure. What do you think about this fascinating discovery?
