A part of the ancient ocean crust deeply buried under the midwest is pulling parts of the crust of North America into the Mental of the Earth, found by scientists.
The discovery published on 28 March in Nature Geosines suggests that the underground process is making a large -scale “drip” under the continent, extending from Michigan to Nebraska and Alabama. These rock drip hangs in deep as 640 km.
“We observed something below Creton,” said Junlin Hua, the lead author of the study.
Researchers say that the reason for this is the Farlan Slab – a survived from the Farlan Tactonic plate that was once pushed below North America along the west coast. Although the plate was broken about 20 million years ago, a large slab remains under the midwest and still pulling the rock material downwards.
This bridge is diluting the base of the continent in a process called crateonic thinning. Creton is the stable fragmentation of the ancient, the earth’s crust that lasts for billions of years. Until now, scientists had never seen the crateonic thinning occurring in real time.
Hua said in a statement, “A very broad range is experiencing some thinning.” “Fortunately, we also got a new idea of ​​what the drive drives to this thin.”
The team used a state-of-the-art imaging technology, called full-waveforms inverted, which uses seismic waves to make high-resolution underground maps. It turns out how the rocks across the continent are being funnel towards the drip area and pulled into the mental.
“This type of thing is important if we want to understand how a planet has developed for a long time,” said Thorson Baker, a geophysicist at UT Austin.
Computer simulation confirmed the findings. When the Farlan slab was included in the models, it appeared to be dripping. When it was removed, the dripping stopped.
Although dramatic in the scale, scientists say there is no reason to panic. The process is very slow and there will be no change in the surface at any time. In fact, it can be completely shut down once the Farlan slab sinks deep into the earth.
This “helps us understand how you make continents, how you break them, and how you recycle them,” said Baker.
The study was supported by the National Science Foundation and UT Austin’s Jackson School of GeoSines, with the contribution of researchers from institutes at Air University, Nevada University and China.
