Professor Wen Lianxing of the School of Earth and Space Sciences, University of Science and Technology of China, etc., used direct seismological evidence for the first time to prove the irregular shape of the edge of the earth's inner core. The international authoritative academic journal Proceedings of the National Academy of Sciences (PNAS) published the results of this research online on April 30.
The inner core of the earth is a solid iron ball the size of the moon. It is surrounded by the outer core of a liquid iron-nickel alloy (and some other lighter elements) flowing at high speed, a high-viscosity mantle, and a solid crust. The inner core of the earth solidifies from the outer core as the inside of the earth cools, and gradually grows outward. In this process, the growth of the inner core generates latent heat and releases lighter elements, providing a driving force for the thermochemical convection of the outer core and the "geomagnetic generator". The external nuclear convection is like the convection of boiling water on the stove, which is considered to be the cause of the earth's magnetic field. The existing concept in the scientific community believes that because the temperature of the outer core changes very little, the solidification process of the earth's inner core is uniform in different geographical locations, so the surface of the inner core should be uniform and smooth, and the driving force of the geomagnetic field generated by the solidification process should also be lateral average.
Under the support of the National Natural Science Foundation of China and the "Innovation Team International Partnership Program" of the Chinese Academy of Sciences and the State Administration of Foreign Experts Affairs, Professor Wen Lianxing's team analyzed and simulated the reflection from the surface of the Earth's inner core from three deep earthquakes in Bandahai The travel time (i.e. the time it takes for the seismic wave to reach the observation point from the source) and amplitude of the seismic wave is found to have at least a 6km horizontal and 14km vertical topography and another 2-4km, vertical A series of terrains undulating 4-8 kilometers. The results of this study prove that the surface of the Earth's inner core is not uniform and smooth, but has at least two irregular terrains of different scales.
The Earth ’s magnetic field intercepts charged particles from the solar radiation and rays from the universe, so that they cannot break through the atmosphere and reach the ground, but stay in high altitude and flow around the earth, which has an important protective effect on the survival and reproduction of living things. The research results of the Wenlianxing team have shown that the driving force for generating the geomagnetic field will also vary with different regions, and the scientific community needs to re-evaluate this.
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