South Korean Crater Yields 10-20 cm Stromatolites, Pointing to 42,000-Year-Old Impact Lake
Updated
Updated · ScienceAlert · May 24
South Korean Crater Yields 10-20 cm Stromatolites, Pointing to 42,000-Year-Old Impact Lake
3 articles · Updated · ScienceAlert · May 24
Multiple stromatolites 10 to 20 centimeters wide were found beneath the Jeokjung-Chogye Basin in Hapcheon, giving researchers what they call the first comprehensive evidence of stromatolites forming in an asteroid-impact hydrothermal lake.
Europium traces, along with elevated calcium, calcite and sulfur in the sediments, indicate the crater once held hot hydrothermal water created by residual heat from the impact.
Radiocarbon dating of one sample places stromatolite formation at about 23,400 to 14,600 years ago, implying the post-impact lake remained hydrothermal for tens of millennia after the crater formed roughly 42,000 years ago.
The team says such crater lakes could have offered refuges for early microbes on heavily bombarded Earth and possibly created localized "oxygen oases" if stromatolite-building organisms were producing oxygen.
Published in Communications Earth & Environment, the finding also sharpens the case for searching other terrestrial impact craters—and potentially Martian ones—for buried microbial structures.
If asteroid craters are 'life oases,' why did Earth's oxygenation take billions of years?
Did an asteroid impact spark life in Korea, and could the same have happened on Mars?
Are the fossils found in a Korean crater truly ancient life, or just a geological mimic?
Stromatolites with Extraterrestrial Signatures Discovered in Korea’s Hapcheon Impact Crater: New Insights into Early Life and Earth’s Oxygenation
Overview
Scientists have made a groundbreaking discovery by finding stromatolites—ancient structures formed by microbial activity—in Korea’s only confirmed impact crater at Hapcheon. After a colossal meteorite impact created the crater, it filled with water and became a hydrothermal lake, providing ideal conditions for microbes. These microbes trapped and bound sediment grains, and their photosynthetic activity increased the water’s alkalinity, leading to carbonate precipitation and the formation of stromatolites. This discovery not only reveals how impact craters can foster early life but also shows a direct link between extraterrestrial events and the origins of life on Earth.