The Earth’s core is a huge ball of liquid metal that is lying at around 3,000 kilometers below the surface. The core is surrounded by a hard and hot layer of rocks that is called mantle. At this depth, both mantle and core undergo very high pressure and temperatures. Researchers have found out that hot buoyant rocks slowly move several centimeters per year and transfer the heat to the surface.
The transfer of heat gradually cooling down the core over geological time. A group of geologists from the Earth-Life Science Institute(ELSI) directed by Kei Hirose started examining the core temperature changes in 2013. They have reported at the Tokyo Institute of Technology(Tokyo Tech) that 4.5 billion years ago from today, during the formation of the Earth the core temperature was 1,000 degrees higher than the present. This temperature loss could be a reason for weakening magnetic field but, scientists have found another energy source that sustains the strength of the geomagnetic field.
These results are the breakthrough in Geoscience and Peter Olson from Johns Hopkins University defined it as,"the New Core Heat Paradox". Their discoveries were first published in the journal of Nature. Scientists faced several difficulties while analyzing the chemical compound of the core. Lead researcher of the study Kei Hirose said in a statement,“The core is mostly iron and some nickel, but also contains about 10% of light alloys such as silicon, oxygen, sulfur, carbon, hydrogen, and other compounds”.
According to Phys report, researchers took a dust-sized sample and placed it inside a diamond anvil. They applied intense pressure that is equivalent to the pressure of Earth’s core. By shooting LASER beam the team created heating samples of Earth’s core. Hirose and his colleagues identified the unique behavior of different alloy combinations by performing experiments under the variety of conditions.
Researchers used various combinations of the alloy to match the environment of Earth’s core. Hirose and his team decided to combine Silicon and Oxygen under this condition. The result was amazing, by analyzing the samples under Electron microscope researchers found Silicon dioxide crystals that are the composition of the mineral quartz. The calculation showed that the silicon dioxide crystals are the powerhouse of Earth’s magnetic field.
The result implied the formation and conditions of the Earth in the earlier Solar System. Dissolved silicon and oxygen get removed by the changing composition during Crystallization. The process of crystallization will stop when then the core will run out of Silicon and Oxygen.
