Scientists indicate that they have discovered an old Earth crust in North America which dates back 4.3 billion years ago. Our planet formed approximately 4.6 billion years ago, and after some hundred million years after the formation, the planet cooled and formed a crust. This piece of old crust which was believed to have been recently discovered appears to have survived subduction.
- Geologists discovered a piece of an old Earth crust in North America.
- The ancient crust was estimated to date back about 4.3 billion years ago.
- Specialists used a new technique to establish the right measurements to reveal the age of the crust.
This represents a process in which the tectonic plates slide under each other, recycling and incorporating back into the mantle. Nevertheless, researchers argue that there remained some slivers of the old rock record. Geologists claim that they have discovered a piece of an old Earth crust along the shore of the Hudson Bay, in Northwestern Quebec, Canada.
The fantastic discovery was made by two geologists who were conducted by Jonathan O’Neil, at the University of Ottawa. O’Neil released the new study, being published in the Science (http://science.sciencemag.org/content/355/6330/1199) magazine. O’Neil argued that he actually believes that the piece of crust was once part of the original crust which formed at the surface of our planet billions of years ago. Nevertheless, he also pointed out that the old crust looks very similar to what scientists assume that the crust uses to be.
Before this finding, the oldest piece of Earth’s crust dated back 2.7 million years ago. However, some pieces of earlier crust remained evasive. Geologists have unearthed the piece of old crust in an area known as “The Canadian Shield,” which represents the ancient geological nucleus of the North American continent. The ancient volcanic rock contains basalt. O’Neil stated that he believes that this was once part of the bottom of Earth’s first oceans.
Researchers used a new technique to date the rock. They measured an isotope which was produced within the first five hundred million years of Earth’s life. The isotope is called neodymium-142. Scientists managed to establish that Earth’s silver formed between 4.2 billion years ago and 4.3 billion years back. This new finding reveals more details about the early development of Terra.
In this way, geologists obtain helpful insights into our planet’s geodynamics. This discovery could be useful when it comes to a better understanding of the formation of other planets in our solar system.
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