New Study Reveals Ancient Ocean Floor Wrapped Around Earth’s Core
Scientists have unveiled the most detailed map to date of the geological composition beneath Earth’s Southern Hemisphere, and it has uncovered a surprising finding: an ancient ocean floor that may encircle the core. This groundbreaking discovery sheds new light on the complex structure of our planet and has important implications for various scientific studies.
Published in the journal Science Advances, the study conducted by geologist Samantha Hansen from the University of Alabama and her team utilized seismic investigations to provide high-resolution imaging of Earth’s interior structure. The researchers found a thin but dense layer, called ultralow velocity zones (ULVZs), approximately 2,900 kilometers (1,800 miles) below the surface. These ULVZs exist at the core-mantle boundary (CMB), where the molten outer core meets the rocky mantle.
According to Hansen, the complexity of Earth’s structure is far more intricate than previously believed, and seismic investigations offer invaluable insights into understanding our planet. The detailed knowledge of what lies beneath our feet is crucial for studying phenomena such as volcanic eruptions and the fluctuations in Earth’s magnetic field, which safeguards us from solar radiation in space.
To map the ULVZs, Hansen and her colleagues deployed 15 monitoring stations deep in the Antarctic ice over a three-year period. By analyzing seismic waves generated by earthquakes, they were able to determine the composition of Earth’s interior. These waves move slower in the ULVZ areas, suggesting the presence of anomalous zones of material at the CMB, potentially representing oceanic crust buried over millions of years.
Geophysicist Edward Garnero from Arizona State University, who was also involved in the study, highlighted the varying thickness of this material, with some areas potentially housing mountains on the core that exceed the height of Mount Everest by five times. Although the cause of these ULVZs is not entirely certain, simulations conducted in the study propose convection currents as a possible mechanism for shifting the ancient ocean floor to its current location.
While making assumptions based on seismic wave movement can be challenging, the ocean floor hypothesis seems the most plausible explanation for the ULVZs at present. However, the thinness of the sunken crust makes it difficult to ascertain whether it wraps around the entire core. Future seismic surveys are expected to provide further clarity on this matter.
Aside from its geological significance, this discovery offers insights into how heat from the core escapes into the mantle. The differences in composition between these two layers far outweigh the distinctions between the solid surface rock and the air above, which provides geologists with crucial information about the overall processes driving our planet.
Hansen emphasized the importance of the research, stating, “Our research provides important connections between shallow and deep Earth structure and the overall processes driving our planet.” As seismic surveys continue to advance, they will play a vital role in unraveling Earth’s mysteries and deepening our understanding of our home planet.
The findings of this groundbreaking study have the potential to revolutionize various fields of science and were met with great enthusiasm among the scientific community. As we continue to explore the depths of our planet, the secrets of Earth’s past and present are gradually being unveiled, giving us a clearer picture of the intricate mechanisms that shape our world.