Could somebody please tell me the specific gravity of the outer core

Question

Also which periods come immediately before and after the Permian.

Please and thank you for your answers.!!!

Answer 1

The density of the outer core is about 9.9 g/cc.  

"The outer core is presumed to be liquid because it does not transmit shear (S) waves and because the velocity of compressional (P) waves that pass through it is sharply reduced. The inner core is considered to be solid because of the behavior of P and S waves passing through it.

Cross section of the whole Earth, showing the complexity of paths of earthquake waves. The paths curve because the different rock types found at different depths change the speed at which the waves travel. Solid lines marked P are compressional waves; dashed lines marked S are shear waves. S waves do not travel through the core but may be converted to compressional waves (marked K) on entering the core (PKP, SKS). Waves may be reflected at the surface (PP, PPP, SS).

Data from earthquake waves, rotations and inertia of the whole Earth, magnetic-field dynamo theory, and laboratory experiments on melting and alloying of iron all contribute to the identification of the composition of the inner and outer core. The core is presumed to be composed principally of iron, with about 10 percent alloy of oxygen or sulfur or nickel, or perhaps some combination of these three elements. "

543 MYA - 490 MYA

CAMBRIAN : Explosion of Life on Earth

The Cambrian Period marks an important point in the history of life on earth; it is the time when most of the major groups of animals first appear in the fossil record.

          

290 MYA - 248 MYA

PERMIAN : Largest Mass Extinction

The Permian period lasted from 290 to 248 million years ago and was the last period of the Paleozoic Era. The distinction between the Paleozoic and the Mesozoic is made a...

          

245 MYA - 65 MYA

MESOZOIC : Age of Dinosaurs

The Mesozoic is known as the Age of Dinosaurs. It also saw the development of early birds and mammals, and of flowering plants (angiosperms). At the end of the Mesozoic,...