Quintero et al., Meteorit. Planet Sci., 2026
Scientists discovered an impact crater that was almost completely erased by geological processes. The crater is particularly notable for being only the second to be found entirely in Archean green rocks, some of the oldest on Earth.
The search for gold in Western Australia led scientists to an extraordinary geological discovery: a rare ancient meteorite impact structurehidden beneath one of the most famous mining regions in the country.
Investigators investigating the Eastern Goldfields region discovered evidence of a long-buried impact craternow known as the Ora Banda impact structure.
The discovery, detailed in a published in the journal Meteoritics & Planetary Science, reveals the remains of a catastrophic collision that occurred millions of years ago and almost completely erased by geological processes.
The structure was initially detected through gravimetric surveys, which revealed a unusual circular anomaly under the desert landscape. Further investigation, including exploratory drilling originally intended for prospecting for gold, has revealed a series of geological clues that point to an ancient meteorite impact, says the .
Among the most significant discoveries were the shatter conesreferring to distinctive cone-shaped fracture patterns created by powerful shock waves during an impact event. The researchers also identified impact breccias, rocks formed when intense pressure shatters and fuses fragments during a collision.
Microscopic analysis of the glassy material trapped in these rocks has provided the strongest evidence to date. Scientists have found exceptionally high concentrations of nickel, cobalt, iridium, platinum, palladium and rhodium, all elements often associated with iron-rich meteoritesbut rarely found in such abundance in the Earth’s crust.
Based on the evidence, investigators believe the structure was formed by the impact of an iron-rich meteorite. The underground crater consists of a central zone surrounded by concentric rings about four kilometers in diameter.
The discovery is particularly significant because Ora Banda is only the second impact structure confirmed found entirely in Archean green rocks, some of the oldest rocks on Earth, dating back billions of years. These ancient formations offer valuable information about the planet’s early history and the role that meteorite impacts may have played in Earth’s formation.
Researchers say Ora Banda offers a rare opportunity to study how meteorite impacts interact with some of the oldest rocks on Earth still exist. The site may also serve as an important analogy for understanding ancient impact events on Mars.
