A study published June 9, 2026, estimates that hydrothermal activity in Chicxulub’s peak ring lasted at least about 8 million years. Hydrothermal activity is the circulation of water heated by hot rock; the study links the system’s longevity to a prolonged window of potentially habitable conditions.
A long-lived system beneath Chicxulub
The study calculates a minimum duration of 7.8 ± 1.3 million years, rounded to about 8 million. It describes that interval as roughly four times longer than earlier estimates for Chicxulub. The estimate concerns the sampled part of the peak ring, not the entire crater.
The impact that formed Chicxulub occurred about 66 million years ago. The research examines four impact-melt-rock samples from three depths—706.4, 735.0 and 756.0 meters below the seafloor—in core M0077A. The core was recovered during a 2016 drilling expedition.
How researchers estimated the duration
The researchers used 40Ar/39Ar dating to measure the ages of minerals in the impact-melt rocks. Potassium-rich feldspar overgrowths in the samples are interpreted as minerals that formed during hydrothermal activity.
The youngest robust age plateau was 58.3 ± 1.3 million years. Compared with the impact age of 66.052 ± 0.086 million years, it yields the 7.8 ± 1.3-million-year minimum. This isotope-based estimate comes from rock samples; numerical simulations provide a separate way to examine how heat and water may have moved through the crater.
What the temperature model estimates
In the study’s 70 °C/km geothermal-gradient simulation, modeled temperatures at about 1 km below the seafloor in the peak ring reached 90 °C 5.5 million years after impact, then about 70 °C after 6.4 million years. The 70 °C/km scenario best matched the temperature measured at the bottom of the present-day borehole.
These are outputs from a specified model, not direct measurements of ancient temperatures. In the same simulation, fluid flow had effectively ceased by 8 million years after impact.
A potential window for habitability
The study evaluates the duration of environmental conditions that could have been habitable. Its findings center on mineral ages and modeled heat and fluid flow, rather than observations of organisms. The distinction matters: an extended period of potentially habitable conditions is a geological result, while evidence of life would require biological or geochemical observations.
What the result may suggest about larger impact basins
The Chicxulub estimate may help researchers consider whether larger impact basins on early Earth could have supported even longer-lived hydrothermal systems. That possibility is an implication for future study; the 8-million-year estimate applies to the sampled part of Chicxulub’s peak ring.
