Massive Bolivian earthquake reveals mountains 660km below our feet.::--
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We know from school that earth interior consist of three layers the crust, the mantle and the core. All the topographic features lies over the crust. But recently seismologists discovered the mountains and other topography within mantle.
Geophysicist used the seismic data from a massive earthquake in Bolivia to find mountains at the depth of 660km boundary. These underground mountains are larger than that on earth surface like Rockies, Andes, Appalachian, Himalayas, Alps,etc .
How and who discovered the topography like mountains within mantle?
The Princeton geophysicists Jessica Irving and Wenbo Wu, in collaboration with Sidao No from the Institute of Geodesy and Geophysics in China discovered the mountains and other topography on a layer located 660km depth, which separates the upper and lower mantle.
For this study they used data of the second largest deep earthquake ever recorded that shook Bolivia in 1994 of magnitude 8.2 earthquake. Seismologists and data scientists use Tiger supercomputers to simulate the behaviour of seismic waves in the deep earth.
Seismic waves (P-waves and S-wave) have ability to reflect(bounce) or refract (bend) when passes through medium. Straight path indicates homogeneous rocks but reflect or refract when they encounter any boundary or roughness. With the increase in one magnitude on Richter scale seismic energy increased by more than 32 times.
We know mantle constitutes 84% of the total volume of the earth. At the depth of 410 km to 660km within a mantle lies a transition zone that separates upper and lower mantle. Below 660km boundary the heat energy cycle (mantle convection) produce two situation :-
1) well mixed upper and lower layers of mantle form homogeneous surface or plains.
2) not mixed, keep thermal and physical difference between the upper and lower mantle , represents the roughness within mantle. These roughness leads to mighty mountains below the 660km boundary.
Geochemical and minerological differences arise due to subduction process of plates . Within the mantle subducted plates does not get melted and thus produce the reliefs like mountains and plains at the 660 km boundary or below.
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We know from school that earth interior consist of three layers the crust, the mantle and the core. All the topographic features lies over the crust. But recently seismologists discovered the mountains and other topography within mantle.
Geophysicist used the seismic data from a massive earthquake in Bolivia to find mountains at the depth of 660km boundary. These underground mountains are larger than that on earth surface like Rockies, Andes, Appalachian, Himalayas, Alps,etc .
How and who discovered the topography like mountains within mantle?
For this study they used data of the second largest deep earthquake ever recorded that shook Bolivia in 1994 of magnitude 8.2 earthquake. Seismologists and data scientists use Tiger supercomputers to simulate the behaviour of seismic waves in the deep earth.
Seismic waves (P-waves and S-wave) have ability to reflect(bounce) or refract (bend) when passes through medium. Straight path indicates homogeneous rocks but reflect or refract when they encounter any boundary or roughness. With the increase in one magnitude on Richter scale seismic energy increased by more than 32 times.
We know mantle constitutes 84% of the total volume of the earth. At the depth of 410 km to 660km within a mantle lies a transition zone that separates upper and lower mantle. Below 660km boundary the heat energy cycle (mantle convection) produce two situation :-
1) well mixed upper and lower layers of mantle form homogeneous surface or plains.
2) not mixed, keep thermal and physical difference between the upper and lower mantle , represents the roughness within mantle. These roughness leads to mighty mountains below the 660km boundary.
Geochemical and minerological differences arise due to subduction process of plates . Within the mantle subducted plates does not get melted and thus produce the reliefs like mountains and plains at the 660 km boundary or below.
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