According to a new study, a massive asteroid that hit the Timor Sea around 35 million years ago may have contributed to the formation of the Antarctic ice sheets.
Andrew Glikson, a specialist in the study of extraterrestrial impacts, from the Planetary Science Institute at the Australian National University in Canberra, who analysed a dome found 2.5 kilometres below the Timor Sea, said there were two obvious explanations for its formation: from a mud volcano or from the movement of tectonic plates.
As per reports of New Scientist , Glikson concluded using electron microscopy and seismic surveys that the dome, called Mount Ashmore, was the result of an asteroid crashing into the earth at such speeds that it caused the Earth’s crust to rebound.
Seismic surveys and aboveground magnetic studies revealed that the dome has a diameter of over 50 kilometres and vertical axis several kilometres in height.
Discovery News reports, “Smaller [asteroid] impacts only create an impact crater. But during larger impacts, something different may happen: an impact dome or central peak rises up in the middle of the crater.” Australian Geographic reports, “Several other craters have been documented from a similar time, including one of the Western Australian coast measuring 120km in diameter. Another asteroid impact structure in Siberia is 100km in size.”
Glikson believes that this asteroid storm may have shifted the earth’s plates to create a gap between Antarctica and South America, known as the Drake Passage, which still exists today.
Discovery News writes, “The rush of water through Drake Passage isolated Antarctica’s climate from the rest of the globe, and fostered the growth of a large ice sheet.”
According to Australian Geographic, these ice sheets in combination with newly-emerging currents around Antarctica may have allowed cooler water into the world’s ocean, and possibly resulted in a well-documented cooling of the planet.
The study appears in Australian Journal of Earth Sciences .
