The asteroid impact that ended the non-avian dinosaurs also created a vast, long-lived hydrothermal system beneath the seafloor, according to a study in Communications Earth & Environment. Researchers analyzed rock samples drilled from the Chicxulub crater in 2016 and used potassium-argon dating to determine when the rocks last solidified. They found the system stayed hot and supplied with nutrients from 66 million years ago to 58 million years ago — at least four times longer than earlier estimates of about 2 million years.
The team, led by geologist Annemarie Pickersgill of the University of Glasgow, also ran computer simulations of hydrothermal flow. Those models suggested that cooling to 90°C took 1.5 to 2.3 million years, while temperatures below 50°C persisted for up to 5 million years, with significant fluid flow ceasing after about 6 million years and ending by 8 million. The simulations matched the rock ages, supporting the longer duration.
The study does not prove that life actually inhabited the Chicxulub system — only that conditions were habitable for millions of years. That distinction matters because hydrothermal systems in underwater impact craters are common, yet microbes have been found in only 8 of 70 such craters. Pickersgill noted that larger impacts on early Earth or other planets could have produced even longer-lived systems, offering extended windows for prebiotic chemistry and microbial colonization. The work helps refine where and how long such environments might persist beyond Earth.