E-PRIME LAYER (Syllabus: GS Paper 1 – Geography)

News-CRUX-10     22nd November 2023        

Context: Recently, a study by an international team of researchers revealed the formation of a new enigmatic layer E prime layer at the outermost part of Earth's core.


E Prime Layer

  • About: There was a belief that the exchange of material between the core and mantle is minimal.
  • Experimental Discovery: However, experiments have shown that when water reaches the core-mantle boundary, it undergoes a reaction with silicon in the core, resulting in the formation of silica.
  • Earth comprises four primary layers: an inner core at the planet's center, surrounded by the outer core, mantle, and crust


How did this layer develop over time?

  • This latest research suggests that tectonic plates carrying surface water have transported it deep into the Earth over billions of years. 
  • Upon reaching the core-mantle boundary about 1,800 miles below the surface, this water initiates significant chemical changes, influencing the core's structure.
  • This reaction leads to the formation of a hydrogen-rich, silicon-depleted layer at the outer core, resembling a film-like structure.
  • Silica crystals generated by this process ascend and blend into the mantle, impacting the overall composition.
  • These modifications in the liquid metallic layer could potentially result in reduced density and altered seismic characteristics, aligning with anomalies detected by seismologists.

Significance of Research

  • This discovery enhances our comprehension of Earth's internal mechanisms, indicating a broader and more intricate global water cycle than previously acknowledged.
  • The transformed layer in the core holds significant implications for the interconnected geochemical processes linking surface water cycles with the deep metallic core.