Ancient Earth’s fingerprints in young volcanic rocks, study shows

Earth’s mantle is made of solid rock that nonetheless circulates slowly over millions of years. Some geologists assume that this slow circulation would have wiped away any geochemical traces of Earth’s early history long ago. But a new study of volcanic rocks that recently erupted from volcanoes in Hawaii and Samoa reveals surprising geochemical anomalies — the ‘fingerprints’ of conditions that existed shortly after the planet formed.
Geology News — ScienceDaily