A new scientific theory suggests that Earth’s inner core could be much older than scientists estimated in their previous studies. Based on new findings, researchers think the freezing of Earth’s inner core took place half a billion years earlier.
Scientists from the University’s School of Environmental Sciences have taken a closer look at Earth’s inner and outer cores. They believe the inner core of our mother planet could have formed earlier than previously estimated, more specifically around 1-1.5 billion years ago. Past research suggested the inner core froze 1.3 billion years ago.
In support of their new theory, researchers have compared various samples from igneous rocks and discovered that the first time when the magnetic field of the Earth became really visible was 1-1.5 billion years ago. The magnetic field of the Earth is the result of the constant turmoil caused by the heat of the outer core and the cold of the inner core; hence, scientists new conclusion.
The outer core of the Earth is a hot liquid that surrounds the solid nucleus of the inner core. The latter formed at a subsequently date when the outer core began to freeze, scientists have explained. The real issue at hand is when exactly the inner core was formed.
There have been many theories in relation to the appearance of the inner core, but neither of them has been universally acknowledged. Until recently, scientists have agreed that Earth’s inner core most likely formed 1.3 billion years ago, but older theories get constantly revisited as new data is discovered.
Dr. Andy Biggin, the lead author of the current study and a paleomagnetism expert at the Liverpool University, thinks the new findings could fuel new information about Earth’s formation. He has confirmed that the fact that Earth’s magnetic field was present 1-1.5 billion years ago is a strong indicator of the earlier date when the inner core was formed.
Biggin has explained that it is very important to find out the date when the inner core was formed because this particular piece of information could shed further light on Earth’s evolution. It could lead to new discoveries about the Earth’s properties, in the author’s opinion.
The current research has further enabled scientists to discover that the inner core gets cooled down at a much faster rate than initially estimated. This causes the solid nucleus at the center of the Earth to become 1mm larger every year.
Scientists will continue to make investigations to understand how the larger size of the inner core affects the magnetic field of the Earth. The findings of the current study were published in the journal Nature.
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