>
- The crater has a diameter of 520 km
- Buried deep under Deniliquin, NSW
- Crater linked to the Late Ordovician extinction event
A rural town in NSW is believed to hide the largest crater on Earth, created by a meteor twice as powerful as the one that caused the extinction of the dinosaurs.
Experts believe the world’s largest meteor crater is buried deep within the Earth in the town of Deniliquin, in the Riverina region of NSW, close to the Victorian border.
The research, published in the journal Technophysics, suggests the impact structure has a diameter of up to 520 km.
The Deniliquin structure is three times as wide as the crater in Chicxulub, Mexico, left behind by the meteor that wiped out the dinosaurs 65 million years ago.
The crater has yet to be tested by drilling, but it is believed to be linked to a mass extinction event.
Experts believe the world’s largest meteor crater is buried deep in the Earth in the town of Deniliquin, in the Riverina region of NSW, close to the Victorian border (photo, Deniliquin)
Research suggests that the crater was created by an impact during the Late Ordovician extinction event between 445.2 and 443.8 million years ago.
About 85 percent of life on Earth was wiped out during the Ordovician.
At the time, the Deniliquin structure was located on the eastern part of the Gondwana supercontinent – before it broke up – and wiped out about 85 percent of life on Earth.
Study co-author Dr. Andrew Glikson said the Deniliquin structure could be even older, suggesting it was caused during the Cambrian era — about 514 million years ago.
Massive asteroids have ravaged Earth in its long history, with Australia recording at least 28 confirmed and 43 potential impact structures.
Dr. Glikson said identifying an impact structure is difficult because the crater can erode over millions of years.
A crater with an uplifted core is left behind after an asteroid impacts “similar to how a drop of water splashes up from a passing crater when you drop a pebble into a pool,” explains Dr Glikson in Live Science.
Australia has at least 28 confirmed and 43 potential impact structures, of which Deniliquin is by far the largest
That central raised dome is an important feature of impact structures, but it can erode over millions of years and become difficult to identify.
“Currently, most of the evidence for the Deniliquin impact is based on geophysical data obtained from the surface,” Dr. Glikson.
“As evidence of the impact, we need to collect physical evidence of the shock, which can only come by drilling deep into the structure.
‘The next step is to collect samples to determine the exact age of the structure. To do this, a deep hole must be drilled in the magnetic center and the extracted material must be dated.’
Scientists and co-author Tony Yeates discovered a magnetic pattern under the Murray Basin in NSW between 1995 and 2000 that indicated a buried impact structure.
Research suggests the crater was created by an impact during the Late Ordovician extinction event between 445.2 and 443.8 million years ago — which was twice as powerful as the meteor that wiped out the dinosaurs
Analysis between 2015 and 2020 revealed the existence of the 520 km wide structure.
The crater has a seismically defined dome at its center – similar to structures found after an asteroid impact.
The Deniliquin crater has all the hallmarks of a large impact structure, including magnetic measurements showing a symmetrical wavy pattern in the Earth’s crust and “radial fractures.”
The magnetic ripple pattern was likely created by the immense heat after the asteroid slammed into Earth.