Rather than being created only during supernova explosions, chemical elements could also be produced deep within the Earth’s lower mantle.
It has long been theorized that hydrogen, helium and lithium were the only chemical elements existing during the big Bang when the universe was formed, and the explosions of supernova, stars exploding at the end of their life, are responsible for the transmutation of these elements into heavier elements and their distribution throughout our universe.
Researchers in Japan and Canada are now questioning one piece of the Big Bang puzzle. Do all the elements heavier than iron really come from exploding stars, or are some created deep in the Earth’s mantle, thanks to convection dynamics driven by plate tectonics?
In AIP Advances, by AIP Publishing, the group proposes an alternative model for the formation of nitrogen, oxygen and water based on the history of the Earth’s atmosphere.
They postulate that the 25 elements with atomic numbers smaller than iron (26) were created via endothermic nuclear transmutation of two nuclei, carbon and oxygen. These nuclei could be confined within the natural core of Earth’s lower mantle aragonite network at elevated temperatures and pressures during lithosphere subduction, which occurs when two tectonic plates converge.
The group describes the endothermic nuclear transformation process as being “aided by the physical catalysis of excited electrons generated by the sliding motion of geoneutrino mineral compounds produced deep in the Earth’s mantle by nuclear fusion of deuterons or radioactive decay of elements.” .
âOur study suggests that the Earth itself was able to create lighter elements through nuclear transmutation,â said Mikio Fukuhara, co-author of the New Industry Creation Hatchery Center at Tohoku University in Japan.
If it is correct, this is a groundbreaking discovery because “it has already been theorized that all of these are from supernova explosions, while we are postulating an additional theory,” Fukuhara said.
This work will have a huge impact on the field of geophysics and could, therefore, “point to possible research directions for the potential to create the elements necessary for future spatial development,” Fukuhara said.
Reference: âEarth factories: Creation of the elements from Nuclear transmutation in Earth’s lower mantleâ by Mikio Fukuhara, Alexander Yoshino and Nobuhisa Fujima, October 12, 2021, AIP Advances.
DOI: 10.1063 / 5.0061584