The World's Oldest Rock Gives Insights On How The Earth's Continents Were Formed
Scientists discovered the world's oldest rock dated 4.02 billion years ago would uncover insights about the earliest history of Earth's crust. The study indicates that the early Earth was oceanic in structure and composition.
Scientists date world’s oldest rock back to 4.02bn yrs https://t.co/akaLq0OWjS
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Jesse Reimink, the lead author of the study said that the rock gives significant information about the early continents formed. He further said that because it's so far back in time, they have to grasp every piece of evidence they can. They have a very few data points with which to evaluate what was happening on Earth at this time.
Science Daily reports that rocks or minerals older than 4 billion years old existed in three locations namely in Northern Quebec, Canada Northwest Territories and mineral grains from Western Australia. The rock that was examined by Reimink has a well-preserved grain of the mineral zircon, which gives the age information. Reimink said that zircons lock in not only the age but also other geochemical information that they have exploited in the study. He further said that the rock records chemical information that the zircon grains don't.
Reimink describes the features on the rock as somewhat interesting. He said that they are different than the way continents are forming on the modern Earth, and also different from how continents were formed further back in time. This refers to something different about early Earth, according to CBC.
The researchers examined the rock to know the chemical signatures and to search the way that the magma meddles into the surrounding rock. Reimink said that while the magma cooled, it simultaneously heated up and melted the rock around it. He added that the chemistry of the rock is similar to that are forming in modern Iceland today, which is transitional between oceanic and continental crust.