麻豆淫院

Earth's largest gold reserves are not kept inside Fort Knox, the United States Bullion Depository. In fact, they are hidden much deeper in the ground than one would expect. More than 99.999% of Earth's stores of gold and other precious metals lie buried under 3,000 km of solid rock, locked away within Earth's metallic core and far beyond the reaches of humankind.

Now, researchers from the University of G枚ttingen have found traces of the precious metal ruthenium (Ru) in volcanic rocks on the islands of Hawaii that must ultimately have come from Earth's core. The findings were in Nature.

Compared to Earth's rocky mantle, the metallic core contains a slightly higher abundance of a particular Ru isotope: ¹⁰⁰Ru. This is because part of the Ru, which was locked in Earth's core together with gold and other precious metals when it formed 4.5 billion years ago, came from a different source than the scarce amount of Ru that is contained in the mantle today. These differences in ¹⁰⁰Ru are so tiny that it was impossible to detect them in the past.

Now, new procedures developed by researchers at the University of G枚ttingen make it possible to resolve them. The unusually high ¹⁰⁰Ru signal they found in lavas on Earth's surface can only mean that these rocks ultimately originated from the core-mantle boundary.

Dr. Nils Messling, at G枚ttingen University's Department of Geochemistry, explains, "When the first results came in, we realized that we had literally struck gold. Our data confirmed that material from the core, including gold and other precious metals, is leaking into Earth's mantle above."

Professor Matthias Willbold, from the same department, adds, "Our findings not only show that Earth's core is not as isolated as previously assumed. We can now also prove that huge volumes of super-heated mantle material鈥攕everal hundreds of quadrillion metric tons of rock鈥攐riginate at the core-mantle boundary and rise to Earth's surface to form ocean islands like Hawaii."

This means that at least some of the precarious supplies of gold and other precious metals that we rely on for their value and importance in so many sectors such as renewable energy, may have come from Earth's core.

Messling concludes, "Whether these processes that we observe today have also been operating in the past remains to be proven. Our findings open up an entirely new perspective on the evolution of the inner dynamics of our home planet."