When you buy through our articles links, Future and its syndication partners can earn commissions.
The only visible parts of the middle holder rupture, mainly basalt outcrop, such as shown, are in the highest lake region. ; | Credit: Don Grall/Getty Images
Fast facts
Name: Middle -level rupture
Location: US MIDWEST
Why is this incredible: Rift in North America almost half 1 billion years ago almost broken.
North America’s “broken heart” is the ancient rectum valley in the Central Western US. The Sagittarius began about 1.1 billion years due to tectonic forces attracted to the present North American continent in opposite directions. Evidence shows that the process of reefling has been suspended 100,000 years After it started, but scientists are not sure why.
The Rift Valley is like horseshoes stretched from Kansas north to Lake Superior and again south to Michigan, based on maps From 2013 In the nature of the article – Although some evidence Offers Rift can continue to south. Geologists estimate that rift was once measured by about 1,900 miles (3000 kilometers) long and created the same width pool as the Red Sea, but most of the structure is now buried under a thick layer of sediment, says National Park Service (NPS).
Map of the mid -bracket, which opened 1.1 billion years ago. | Credit: US Geological Survey
According to the NPS, the only visible parts of the rupture today are near the Superior Lake, where huge blocks of basalt and other feathers are associated with blocks. Basalt is dark, fine-grained, so dense-oes formed from fast cooled lava. When the Earth’s crust was torn during the rifle process, the Magma rose to fill the crack, creating a hardened lava and magma belt in the valley.
Rift probably opened now because in the middle west, because the Earth’s crust was already fragile – NPS, according to NP, a large magma fiber could weaken the surface and stained the fate of the region. As the rifle improved, the molten rocks rose and caused volcanic eruptions, depositing huge dense substances such as basalt, due to the rift valley immersed in the crust.
“Impressive failure”
For the reasons why scientists are debating, reefing and eruptions stopped, causing the sediment to settle on the volcanic material. However, the rift valley did not stop drowning, as the weight of the sediment pushed the structure deeper into the crust.
Related: Turning dome: Utah’s “belly button” that divided scientists from its discovery
After the rifle, there was a compression period when the crust pieces were crushed on each side of the rift valley. According to the NP, this pushed the volcanic material and sediment, revealing parts of the rift valley, which were later covered with sediment.
Cyclic glaciers’ growth and numbness have removed some of these sediment over the last 2.5 million years, resulting in still visible parts of the slit. Near the Superior lake-ypaci northern Michigan Keweenw Peninsula-Academy-of-Basalt and Copper rich rocks. People dug this copper At least 8,000 years – and although the mines are closed in the late 20th century, the industry is now seeing the rebirth;
Why the rifle ended after 100,000 years remains a bit unclear.
“It’s an impressive failure” G. Randy Keller2013 In the Nature article, a professor of geophysics at the University of Oklahoma and director of the Oklahoma Geological Survey. “How this feature could simply rearrange the Earth’s crust in the Lake Supreme Region and not be able to ruin the continent separately is quite wonderful.”
More incredible places
—L cones: The mysterious holy “pyramid” hidden deeply in the Amazon rainforest
—Aran folded rocks: crushed mountains at the intersection of Asia and Europe
—Wilkes Land Crater: A giant hole in the eastern Antarctic gravitational field, which is most likely caused by a meteorite
Geologists have been studying this issue for more than a decade, some scientists with some scientists by linking the failure In the mountainous episode along the North American Atlantic Ocean. Other researchers reject this theory, instead offers The rifle ended when the sea between Laurentia and Amazon, the North and South American geological cores.
Meanwhile, the Rift Valley sections in Kansas have attracted the attention of resource exploration companies; Basalt can react with water to get hydrogen, which is a source of clean energy and an ingredient in basic chemicals, living science has previously reported.
Discover more Incredible placeswhere we emphasize the fantastic history and science behind the most dramatic landscapes on Earth.