Distinct Compositions of Africa and Pacific LLVPs Reveal Earth’s Secrets
A new study identifies significant compositional differences between the LLVPs beneath the African and Pacific plates, countering previous beliefs of their similarities. The African LLVP is older and more mixed, while the Pacific LLVP exhibits characteristics from ongoing volcanic replenishment. These distinctions impact our understanding of the Earth’s magnetic field and heat extraction processes.
A recent study has uncovered significant differences between the Large Low-Velocity Provinces (LLVPs) beneath the African plate and the Pacific plate, challenging prior assumptions of their similarities. These LLVPs, larger than continents, extend approximately 900 kilometers up and have distinct chemical compositions and histories. The African LLVP is found to be older and more diffuse than its Pacific counterpart, which is influenced by a frequent volcanic activity in the Pacific Ring of Fire.
Research based on seismic wave analysis reveals that LLVPs have varying compositions due to differing geological histories. The slower movement of seismic waves through these regions indicates significant divergence in their development. The Pacific LLVP, subject to repeated subduction interactions, displays characteristics distinct from the African LLVP, enriching its material with oceanic crust constituents over time.
Dr. James Panton, the lead author of the research, emphasizes the implications of these differences, particularly regarding the Earth’s magnetic field. He notes, “As numerical simulations are not perfect, we have run multiple models for a range of parameters. Each time, we find the Pacific LLVP to be enriched in subducted oceanic crust, implying that the Earth’s recent subduction history is driving this difference.” This study sheds light on the heat extraction dynamics from the Earth’s core, as the structure of LLVPs may influence magnetic field stability.
The recent investigation into the LLVPs beneath the African and Pacific plates reveals critical differences in their composition and geological history. The African plate, characterized by age and a lack of recent geological activity, contrasts sharply with the younger, dynamic Pacific plate. These findings have profound implications for our understanding of the Earth’s magnetic field and highlight the need for further research into these mysterious structures.
Original Source: www.indiatoday.in
