Billion Years Ago, a Rift Nearly Split North America in Two and It Left Behind a Mysterious Scar
Around a billion years ago, a geological event occurred in North America that could have completely changed the continent as people know it. This event could have split the North American continent in two, but for some reason, it suddenly stopped, according to Daily Galaxy.
The event in question is an ancient rifting process, which, as per experts, started 1.1 billion years ago and continued for 100,000 years. This process ran through the entire North American continent and facilitated a massive scar on the continent's surface, which to date remains. This 2,000 km scar on the U.S. Midwest is labelled Midcontinent Rift.
The giant scar has also been nicknamed North America's 'broken heart' by enthusiasts, according to Live Science. As per experts, this 'broken heart' could have torn apart the continent if it were allowed to progress. This Midcontinent Rift runs from Kansas north to Lake Superior and then runs south again in Michigan. The whole structure looks somewhat like a horseshoe.
Geologists believe that at one point, the rift possibly measured around 1,900 miles (3,000 kilometers) long and had a basin as wide as the majestic Red Sea. Over the years, glacier cycles have eroded a lot of the rift, and most of the rift valley now remains under sediment. Experts have detected solidified magma and lava in the rift valley. At present, the only portions of the Midcontinent rift that are visible are near Lake Superior. Here, huge blocks of basalt and other rift-related rocks, which make up the scar, stand out.
Researchers think that the rifting process was triggered by tectonic forces that were pulling the North American Continent in opposite directions. The experts also claim that the Basalt visible near Lake Superior was also formed during this pulling apart. They believe that when the Earth was torn apart, lava erupted to the surface and solidified. During its cooling, several Basalt rocks came into existence.
Geologists believe that the rift opened up on Earth's surface in the present-day Midwest because, for some reason, the crust was already weak there. Experts speculate it could be because of an ancient blob of magma, already present there, that the surface was weak enough to be impacted by the ongoing rift. The whole process caused several molten rocks to rise, which in turn triggered volcanic eruptions. These eruptions deposited a lot of dense material in the rift valley and caused it to sink into the Earth's crust.
Geologists claim that the rift could have created a new ocean between two portions of the continent, but for some reason stopped, according to Daily Galaxy. Some scientists think the halt happened due to mountain building on North America’s Atlantic coast, while others think that the formation of the sea between Laurentia and Amazonia could be the culprit. To date, none of the theories has been proven correct.
Many scientists are also stunned that despite being so powerful at its peak, the rift did not manage to break the continent before the stoppage. "It’s incredible that something of this scale could remodel the crust of the Earth in the Lake Superior region and not manage to break the continent apart," G. Randy Keller, professor emeritus of geophysics at the University of Oklahoma and director of the Oklahoma Geological Survey, shared. He believes it was a "spectacular failure" for the strong rifting process.