Photo credit: www.gadgets360.com
A newly observed underground structure in the central United States has been identified as a significant factor in the movement of surface materials deep into the Earth. This action has been attributed to ancient crustal remnants located far below the Midwest region. Researchers indicate that this process is actively pulling rocks from across the continent toward a funnel-shaped area, leading to a thinning of the crust as material is drawn down. The implications of this phenomenon extend beyond the Midwest, affecting a broader geographical scope.
Connection to Crust Loss Under the Midwest
A recent study featured in Nature Geoscience establishes a link between this underground activity and the remnants of a tectonic plate known as the Farallon slab. Positioning approximately 660 kilometers beneath the Earth’s surface, this slab is recognized as a catalyst for what scientists are describing as cratonic thinning. Cratons represent the stable, inner sections of continental crust and upper mantle that are typically resistant to change.
The seismic mapping initiative was spearheaded by Junlin Hua during his postdoctoral research at The University of Texas at Austin, where he is now a faculty member at the University of Science and Technology of China. In a statement, Hua pointed out that a broad region is exhibiting signs of crustal thinning, marking a notable finding that provides a fresh explanation for these geological developments.
Innovative Seismic Method Reveals ‘Dripping’ Lithosphere
Employing a technique known as full-waveform inversion, researchers were able to monitor the geological changes occurring beneath North America with unprecedented clarity. This advanced seismic imaging method facilitates high-resolution subsurface mapping. According to Thorsten Becker, the Geophysics Chair at UT Austin, this approach enhances the comprehension of the relationship between deep mantle areas and the overlying lithosphere.
Additionally, computer simulations played a crucial role in confirming the observed phenomena. The inclusion of the slab in these models illustrated a definitive downward movement, whereas its removal resulted in the disappearance of this movement, underscoring its significance in the overall geological landscape.
Source
www.gadgets360.com