Overview
- Curtin University researchers published a study Tuesday, June 23, reporting concordant uranium–lead ages of about 3.02–3.024 billion years from zircon grains they interpret as impact‑modified and from apatite formed by post‑impact hydrothermal fluids.
- The team says those two independent mineral clocks give a direct date for the North Pole Dome (Miralga) event and, if accepted, make it the oldest recognised terrestrial impact structure.
- Some independent geologists continue to dispute the 3.02 billion‑year interpretation and argue the impact must be younger based on mapped rock relationships and documented shatter cones tied to nearby rocks dated at about 2.77 billion years.
- Curtin researchers argue the mineral textures and the matching zircon and apatite ages are best explained by an impact and by late hydrothermal fluid flow, while critics say long‑distance stratigraphic correlations and alternative hydrothermal events could account for the signals.
- Resolving the disagreement will require more targeted field mapping, petrographic study and additional geochronology, and the outcome could change how scientists view early Earth processes and possible habitats for ancient microbial life.