A new research reveals that the outer crust of the earth under the mountains of Sierra Nevada, California, is sinking into the cloak.
Geologists have discovered evidence of a rare geological process, called lithospheric “founding” under the mountains of Sierra Nevada, California. This phenomenon occurs when the rigid outer layer of the earth, the lithosphere, becomes too dense and sink slowly in the hottest cloak and fluid below.
The lithosphere, the solid outer crust of the earth, behaves like a floating shell over the cloak. Over millions of years, dense sections of the lithosphere can break and down to the cloak. Although scientists have theorized for a long time on the role of lithosphere erosion in geology From the earth, the concrete tests have been difficult to obtain – so far.
In a new published in Geophysical Research Letters, researchers at the University of Colorado in Boulder and the University of California in San Diego analyzed seismic data and earthquake records. Their discoveries revealed weak seismic tremorswith magnitudes between 1.9 and 3.2, which occur more than 40 kilometers below the central nevada sierra. These tremors point to a thinning of the cloak layer that aligns with the theory of the foundation of the lithosphere, says.
The study suggests that, millions of years ago, a dense section of the lithosphere under the southern sierra began to sink into the cloak. This process continued for at least 3 million years and now it seems to be progressing north under the mountain range.
The researchers explain: “The impression we have in the rocks on the current border between the crust and the cloak records a dense portion that comes off under the snack on California.” The authors add that, while the southern region of Sierra Already detached itself largely From its dense lithosphere, the central region is still undergoing this slow sinking process, which is causing the small and deep seismos observed today.
Although this discovery may seem alarming, the investigation does not suggest that California is at risk of a dramatic geological collapse. Sinking of the lithosphere is an extremely slow process that occurs in the depths of the underground, far from surface disturbances.
However, discoveries can offer valuable information about the construction of continents and the tectonic plates, which shapes the earth’s terrestrial masses along geological time scales.
