A circular pit on Google Maps becomes a major geology discovery

A circular feature first noticed on Google Maps has led scientists to identify a previously unrecognised meteor impact structure in remote Quebec. The structure, now named Uhackatik, is reported in the Meteoritical Society technical programme as a new 25 km diameter impact structure, approximately 390 million years old. The same abstract states that the site contains well-preserved shatter cones and around 50 m of impact melt rocks, key evidence for a hypervelocity impact origin.

The discovery began when an amateur observer noticed an unusual circular depression while exploring satellite imagery for a camping trip. What could easily have been dismissed as a natural lake basin or eroded topographic feature instead attracted the attention of planetary geologists. Researchers later visited the rugged site, collected samples and documented geological evidence consistent with a large ancient impact.

The findings are expected to be presented at the annual congress of the Meteoritical Society in Germany, a major international meeting for planetary science and impact research.

A 390 million year old impact crater will rarely look like a fresh bowl-shaped depression. Over geological time, erosion, glaciation, sedimentation, vegetation and later landscape evolution can heavily modify the original crater form. In places like Quebec, forest cover and rugged terrain can also hide large circular structures from field recognition.

This is why satellite imagery and digital elevation data have become useful tools in geological discovery. A circular pattern seen from above is not proof of an impact, but it can guide researchers toward promising targets. The real confirmation must come from field geology and laboratory analysis.

At Uhackatik, the most important evidence includes impact melt rock and shatter cones. Impact melt rock forms when the extreme energy of an asteroid impact melts part of the Earth’s crust. Shatter cones are distinctive fractured rock structures produced by shock waves and are widely recognised as strong evidence for impact events.

The Quebec discovery is important because confirmed impact structures are rare at the Earth’s surface. Unlike the Moon or Mars, Earth constantly recycles and erases its geological record through erosion, plate tectonics, sedimentation and biological cover. Many ancient impact scars may therefore remain hidden, distorted or only partly preserved.

At around 25 km in diameter, Uhackatik is not a small feature. If confirmed through full peer-reviewed publication, it will add an important new data point to the history of impacts on Earth and to the geological evolution of eastern Canada.

The discovery also shows the value of public observation. A single unusual pattern on a digital map led to a difficult field expedition, rock sampling and the identification of features that may record one of Quebec’s major ancient impact events.