About 66 million years ago, a giant asteroid slammed into Earth and wiped out the dinosaurs, along with around 70% of all life in the oceans.
The impact left behind a massive crater under what is now the Gulf of Mexico.
While it’s mostly known as the site of mass extinction, scientists have now discovered that this crater also became a surprising place for life to recover.
A new study published in Nature Communications shows that the area around the impact site, called the Chicxulub crater, became a hotspot for new marine life soon after the disaster.
For at least 700,000 years after the asteroid hit, the crater supported a rich underwater environment, thanks to a special kind of natural heating system called a hydrothermal system.
After the asteroid impact, extremely hot rock deep beneath the seafloor created this hydrothermal system, where water heated by the Earth’s heat flowed through the crust and brought nutrients up to the ocean floor.
These nutrients helped life in the area bounce back more quickly than in other parts of the world.
Lead researcher Honami Sato from Kyushu University in Japan said that the recovery at the Gulf of Mexico was very different from the rest of the world because of this constant hydrothermal activity.
Instead of being a dead zone, the crater became a unique marine environment that helped life flourish.
The study builds on earlier work done in 2016 when scientists drilled into the crater and brought up 829 meters of rock and sediment samples. Those core samples have revealed many new details about the effects of the asteroid, and this latest research focuses on a metal called osmium.
Osmium is important because certain types of it can be traced back to asteroids.
The scientists found that osmium from the original asteroid was still being released into the ocean long after the impact, carried by the hot fluids from below the seafloor.
As these fluids cooled, they deposited osmium in the surrounding sediment. By studying these layers, the team figured out how long this nutrient-enriching process lasted.
The scientists also found that the types of tiny sea creatures called plankton living in the area changed over time. When osmium levels were high, the plankton were ones that thrive in nutrient-rich waters.
But when osmium levels dropped back to normal, the plankton shifted to species that prefer low-nutrient environments. This showed that the hydrothermal system was likely fueling the local ecosystem during the early recovery period.
Eventually, the system stopped feeding the ocean, although it kept running deep below the surface for millions of years. Over time, it was buried under more and more layers of sediment.
While the Chicxulub impact is famous for causing mass extinction, this research shows it also helped create the conditions for life to recover—and thrive.
Co-author Steven Goderis from Vrije Universiteit Brussel said this study shows that even destructive events can lead to new life.
And researcher Sean Gulick from the University of Texas added that this kind of hydrothermal activity could be important in the search for life on other planets too.
