Monday , June 5 2023

huge crater discovered in Greenland – here is how the impact could & # 39; removed the mammoths


ice sheet in Inglefield Land & # 39; Greenland hide the krater of & # 39; Hiawatha. Credit: Museum & # 39; Natural History of Denmark, Kriżeriku Science Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA

Scientists have discovered a krater & # 39; & # 39 wide impact; 31 km below the glaciers & # 39; Hiawatha in Greenland. The discovery, published in Scientific Advances, Made with the use of & # 39; radar survey revealed depression air circular rock bottom under the ice. The presence of quartz and other particles and features in the ground helped the team confirms the finding – they showed signs subjected to high pressures of & # 39; shock.

The grains analysis also shows that the impact x & # 39; likely was made from iron meteorite of & # 39; more than 1 km wide. It was there during the Pleistokenu, between about 12,000 and 3 million years ago. This is by no means the only kattur of great impact in the World, and research shows how those features can teach about the history of our planet – including the evolution of life. So how can & # 39; impact & # 39; Greenland changed our planet?

Many of the older impacts from space occurred on the oldest shells of our planet and the center of its large continental plates tekontiċi. Unfortunately, this crust is constantly renewed – older rock is destroyed by weather processes and waste are recycled in & # 39; new ships. This process destroys evidence & # 39; early impacts from large bodies. In addition, many kraters impact (often mistaken for an extinct volcanic kraters) formed a circular lake, which means that many properties lost due to water erosion.

Despite this lack of & # 39; evidence, we know that the meteorite impacts can produce dramatic changes in the local environment. larger ones may even have a drastic effect on the global environment – leading to mass extinctions. The big hat & # 39; Chicxulub in Mexico, for example, is believed to have contributed to killing the dinosaurs.

ice sheet in Inglefield Land & # 39; Greenland hide the krater of & # 39; Hiawatha. Credit: Museum & # 39; Natural History of Denmark, Kriżeriku Science Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA

But as one of the localized impact warns all species? The initial impact and wave & # 39; shock from an asteroid might erode clear in life & # 39; substantial radius. Everything gets heat of & # 39; impact – produce barren desolate landscape. Shock waves passing through the planet's body can also lead to destructive earthquakes, tsunamis and volcanoes.

But are the lasting effects of the impact that has the potential to cause the most serious changes. large volume & # 39; debris ejected from the krater can & # 39; travels the & # 39; and now spread worldwide. B & # 39; & # 39 outcome; this, a larger number of & # 39; particles in the atmosphere can & # 39; block the sunlight, climate change and preventing photosynthesis – in the ultimately has a devastating effect on the food chain. Eventually, the particles in the atmosphere come back to Earth and the light returns, along with life. The species may be able to live and prosper in & # 39; new world where much larger creatures, as was the case with the dinosaurs, now extinct.

Obviously, these events & # 39; re turning impact of World history and paved the way to aid in the evolution of our species. It is interesting to think about if the world is the same now if the Chicxulub impact never happened – or even the impact found in Greenland.

BARRINGER crater. Credit: D. Roddy (LPI) / NASA

The extinction & # 39; Greenland?

There is evidence that three impacts are possibly related to & # 39; & # 39 events; mass extinction, including Kretaċe events caused by Chicxulub-Palegene. We also know that the majority of marine species and terrestrial vertebrates became extinct during the Triassic event & # 39; Permian some 252 million years ago, believed to have been caused by the impact of the asteroid that left behind -Land crater & # 39; Wilkes in Antarctica. Meanwhile, the Siberian Popigia impact about 35 million years ago is linked to the Eocene-Oligocene event, which wiped out many marine species.

All these impacts have created craters of & # 39; a whopping 100km around or more (for Chicxulub 170km), suggesting that the krater of & # 39; 31 km in Greenland could not have been so devastating to Earth. However, it was drastically alter the local environment and reset the race of life in & # 39; that area.

If it is really true that the creator of & # 39; Greenland was created 12,000 years ago or more, can & # 39; explains mysterious feature called the younger Dryas event. This was a change in & # 39; sigh and dramatic climate – glacier period & # 39; up about 12.900 11.700 years ago, followed by a gradual global warming. Previously, scientists believed that this event was caused by an explosion & # 39; meteoru before impact, which would have also caused changes in the local environment.

Kurt Kjær collect sand samples in front of the Glacier Hiawatha. Credit: Svend Funder

The climate change in & # 39; blow is deemed to have a drastic effect on large mammals & # 39; American & # 39; On. For example, it is believed that helped cause the extinction of mammoths and mastodon. We know that many of the woolly mammoth populations disappeared between 14,000 and 10,000 years ago. Collection & # 39; ancient human hunters could & # 39; also had to adapt to cope with climate change from this event by changing the hunting habits or even migrate to more suitable areas.

It is clear that the impact of space & # 39; have devastating consequences for life on Earth. So x & # 39; happening today? Center Plant Minor f & # 39; Massachusetts, USA, has been collecting and categorizing the orbit & # 39; asteroids and comets by 1947, and NASA has a similar program & # 39; Near Earth Objects. If a body is found to be on a course interċettwali plans & # 39; prevention set, ranging from deflection and the launch of & # 39; spacecraft to the asteroids moved to a new orbit the asteroid to open up. Unfortunately, they all have their disadvantages and take many years to plan – which means that work can & # 39; be a little too late.

Indeed, the late physicist Stephen Hawkins stated that collision & # 39; the asteroid "is the greatest threat to our planet" and one that we can not control it. Despite the monitoring and all our preparation, great body can & # 39; hear & # 39; quickly. And, because the previous impacts taught us, while the damage can & # 39; not enough to destroy the world, you & # 39; change dramatically – perhaps even the best.

Explore more:
Crater that killed the dinosaurs shows how broken rock can & # 39; is liquid

the Journal reference:
Scientific Advances

Awarded by:
The Conversation

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