The Earth's inner core, a solid sphere and viscous iron and nickel that is located in the deepest part of the world, grows about an inch each year,
said Jaime Urrutia Fucugauchi.
The researcher of the Institute of Geophysics, National Autonomous University of Mexico (UNAM) explained that this part of the planet has a radius of
one thousand 220 kilometers, but over time becomes larger, as shown by various methods to calculate their size and characteristics.
In a statement, geophysical engineer and doctor of paleomagnetism stated that the inner core liquid surrounding an area with a radius of two thousand
100 kilometers, comparable to an ocean with iron, but instead of water.
The inner core was discovered in 1936 by Inge Lehmann's Danish seismologist, while working on the revision of seismograms and noticed that the
transmission speed of seismic waves that cross the Earth's interior had a slight variation.
Seismologist and calculated these variations and found that within the nucleus had a smaller, inner, both with different characteristics.
Urrutia explained that the way to explain is that when the waves enter the outer core, the velocity decreases, it is a low-velocity zone, "but then
re-accelerate in the solid phase."
The outer core has a low viscosity, is fluid and has been compared to an ocean made of iron, the other, in contrast, is solid, research abounded in
2009 awarded the National Prize of Sciences and Arts.
The earth structure continues to the mantle, the middle layer and largest balloon that is 83 percent of the planet, between two thousand and two
thousand 900 800 km thick, and where internal forces are generated, such as drift continents, the expansion of the oceans and the occurrence of
The outermost layer is the crust, with a thickness ranging from 30 to 40 km on the continents, and about 10 kilometers beneath the oceans. The top is
composed of rocks of the type granites, and denser than other, as basalts and gabbros.
edit on 30-12-2011 by newyorkee because: (no reason given)