Asteroid That Killed the Dinosaurs Reportedly Caused ‘Mega Earthquake’ That Lasted Months

by Craig Garrett
Dinosaur extinction day - stock photo

A new study says that the asteroid which caused the extinction of the dinosaurs caused an earthquake that shook Earth for weeks to months. 66 million years ago, an asteroid 10 kilometers wide hit Earth, setting off the dinosaurs’ extinction, EureakAlert! reports. New proof suggests that this Chicxulub impact also caused a massive quake. It was so large that it shook the planet for weeks or even months after the collision.

The energy released in this “mega-earthquake” is around 50,000 times more than the Sumatra earthquake of 2004. That quake had a magnitude of 9.1. Hermann Bermudez, a geologist at Montclair State University in New Jersey, measured the severity of the impact’s earthquake by visiting K-Pg mass extinction outcrops in Texas, Alabama, and Mississippi.

Bermúdez discovered spherule deposits in 2014 while doing fieldwork on Colombia’s Gorgonilla Island. These layers of sediment contain small glass beads (1.1 mm at most) and shards known as ‘tektites’ and ‘microtektites,’ remnants of an asteroid impact that heated and pressurized the Earth’s crust until it melted, scattering melted blobs into the atmosphere. The blobs cooled to form glass under the influence of gravity before falling back to Earth’s surface.

More on the research that led to the discovery of the ‘mega earthquake’

The spherules and tektites found along the coast of Gorgonilla Island tell a tale. They showed what had happened on the seafloor around 1.25 miles underwater at the time of the asteroid’s impact. As the Chicxulub impactor hit Earth, layers of mud and sandstone below 33 to 50 feet beneath ocean floor were deformed. Bermúdez theorizes that this deformation captured in outcrops today was due to shaking associated with the impact.

Bermúdez elaborated on his findings. “The section I discovered on Gorgonilla Island is a fantastic place to study the K-Pg boundary because it is one of the best-preserved and it was located deep in the ocean, so it was not affected by tsunamis.” In Mexico, where he found the fingerprint of liquefaction, Bermudez discovered evidence of a mega-earthquake triggered by the Chicxulub impact, with the signature of liquefaction, in which water-saturated sediments flow like a liquid.

The mega-earthquake also created deformations in Mexico and the United States. Amazingly, people can still see them today. He also took photographs of tsunami deposits at several outcrops. These resulted from an enormous wave that was a part of the cascading disasters caused by the asteroid collision. While at the sites in Mississippi, Alabama, and Texas, Bermúdez discovered cracks and faults. These were likely created by the mega-earthquake caused by the Chicxulub impact. Waves from a resulting tsunami deposited several layers of sediment at these outcrops. This is another sign of the asteroid’s devastating crash into Earth.