Universe Today has an article stating researchers have discovered a new layer to the our shiny blue marble. The Earth's layers have been tradiitonally defined as the crust (the surface where we live), upper and inner mantle, and outer and inner core, but scientist studying the Earth's interior have discovered an inner, inner core within the center of the Earth. The rotation of Earth's iron core generates the planetary magentic field that shields us and every other living organism from stellar radiation.
University of Illinois @ Urbana-Champaign were using naturally occurring seismic sound waves to study the core, which consists of a solid inner layer and a fluid outer layer. When the examined the results form the inner core, they discovered an anomaly in the results that led to the discovery.
"The team was specifically studying how the waves were affected as they passed through the solid inner core and were surprised to see that it wasn't a uniform sphere of iron.
Instead, the seismic waves clearly showed that there's an additional layer at a diameter of 1,180 km (733 miles), which makes this less than half the diameter of the inner core. This is the Earth's inner, inner core.
So what is it? Here's what the lead scientists, Xiaodong Song had to say:
"Our results suggest the outer inner core is composed of iron crystals of a single phase with different degrees of preferred alignment along Earth’s spin axis," Sun said. "The inner inner core may be composed of a different phase of crystalline iron or have a different pattern of alignment."
Interesting, still iron but formed into a different type of structure. Still no Lost World full of dinosaurs though, sorry Jules Verne.