A few hundred metres from the lake on the east side of Crater Lake in northern Oregon lies the crater of a large asteroid that crashed about 6,000 years ago.
A recent study led by the University of Arizona suggests the crater was a small, two-kilometre-wide, four-meter-wide impact crater, the size of a small parking lot, but the researchers aren’t quite sure what caused it.
“It’s hard to make a solid judgment on how much impact crater there was,” said Chris Schreiber, a geochemist at the University’s School of Earth and Atmospheric Sciences in Tucson, who wasn’t involved in the study.
It’s possible there was an impact, he said, but it’s hard for a crater to be that small.
The crater’s composition may have changed significantly from that of the crater it was made of.
The researchers estimate the impact site is about 7 kilometres (4 miles) from the crater rim.
This is where researchers hope to drill down into the ground to study the rock.
In the meantime, they plan to drill more than 200 metres down into a lake in the area.
They have drilled hundreds of holes, using different methods to collect samples of rock and water that were trapped beneath the water in the past, including water that had evaporated.
For example, a team drilled a 20-metre-deep hole into a rock called pterosaur bone from a nearby lake.
Schreiber said the drillers will continue to collect the samples as they do so.
Researchers are working to determine whether the crater’s origin is related to a meteorite or a comet, or if there is another crater that could have formed.
They also hope to understand how a larger crater formed, as well as its structure.
If the crater formed by an impact of a comet or asteroid, it could tell scientists about how it formed.
Scientists hope to get to the bottom of the issue in a paper to be published in the journal Science.
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