The pyrosphere is the core of the earth. They are made of two elements (Nikel and Iron). The inner core is harder than the outer core because of the material it contains while the outer core is semisolid.
Available information shows that the globe consists of collections of concentric layers which becomes denser towards the center. From the interior outwards,the successive layers are the pyrosphere ( Core or Nife),Barysphere (mantle),and the Lithosphere (crust=sial+sima). These layers are enveloped by hydrosphere and the atmosphere which is the outer layer of the globe.
1.THE CORE: This is the deep interior of the globe. It is the largest part of the earth,a spherical central zone about 3,400km in radius and consists of two parts.
i.THE INNER CORE (GRAIN OF THE CORE):these forms the solid inner most part of the earth, about 1,300km in radius and maybe solid and crystalline.
ii. THE LIQUID OUTER CORE: About 2,100kms thick which lacks rigidity. The core has metaluc property and a very high density. Its mean density is 10.72grams,that of the central part is about 12.3grams while the out periphery of the core has a density of about 8.0grams. The main component of the core are Nikel and Iron,hence,the nickname Nife.The core has remarkable high temperature, high pressure and high specific gravity in the core. Its temperature is estimated to be between 1,925°c and 4,416°c,pressure is high as 3 to 4 million times sea level pressure and specific gravity of 10 to 15. The boundary between the core and the mantle is known as the "Wiecher-Gutenburg discontinuity".It was discovered in 1914 by a man called 'Ben Gunten burg of Germany'.
2.THE MANTLE: This surrounds the core and its about 2,900kms thick. Its mean density is 453grams. The mantle is the zone of heavy rocks often referred to as substratum, and it is believed to be composed of mineral matter. It is probably made up of mineral matter, and it is called OLIVINE(magnesium and iron silicate) which comprises a basic rock variety called DUNITE a rock which maybe in glassy state.
3.THE CRUST: The crust is the outer most of the concentric earth zones. It is a shell of regular thickness with an average thickness of 35kms. The crust consist of two zones with contracting dominant rock types.
i. A Lower Basoltic Zone: this is composed of dark and heavy rocks consisting mainly of basolt and related rock types with a density of about 2.8 to 3.0gram and still heavier ultra basic rocks(density up to 3.4grams).
Silica is the most abundant constituent of this rocks while iron oxide and magnisia,either single or together. The whole group is known by the term "SIMA".
ii. OUTER GRANITE ROCK:this is composed of light rocks including granite and rated rocks which have an average density of about 2.7grams.The rocks are collectively know as "SIAL".
The mantle is enveloped by the crust and separated from it by a major discontinuity zone known as the "mohorovicic discontinuity" or briefly as Moho discontinuity.This boundary was discovered in 1909 by a Croatian is irregularly covered by a sedimentary layer which varies in depth from zero in some places to a maximum depth of about 9,150meters in some depressions and river valleys.
Available information shows that the globe consists of collections of concentric layers which becomes denser towards the center. From the interior outwards,the successive layers are the pyrosphere ( Core or Nife),Barysphere (mantle),and the Lithosphere (crust=sial+sima). These layers are enveloped by hydrosphere and the atmosphere which is the outer layer of the globe.
1.THE CORE: This is the deep interior of the globe. It is the largest part of the earth,a spherical central zone about 3,400km in radius and consists of two parts.
i.THE INNER CORE (GRAIN OF THE CORE):these forms the solid inner most part of the earth, about 1,300km in radius and maybe solid and crystalline.
ii. THE LIQUID OUTER CORE: About 2,100kms thick which lacks rigidity. The core has metaluc property and a very high density. Its mean density is 10.72grams,that of the central part is about 12.3grams while the out periphery of the core has a density of about 8.0grams. The main component of the core are Nikel and Iron,hence,the nickname Nife.The core has remarkable high temperature, high pressure and high specific gravity in the core. Its temperature is estimated to be between 1,925°c and 4,416°c,pressure is high as 3 to 4 million times sea level pressure and specific gravity of 10 to 15. The boundary between the core and the mantle is known as the "Wiecher-Gutenburg discontinuity".It was discovered in 1914 by a man called 'Ben Gunten burg of Germany'.
2.THE MANTLE: This surrounds the core and its about 2,900kms thick. Its mean density is 453grams. The mantle is the zone of heavy rocks often referred to as substratum, and it is believed to be composed of mineral matter. It is probably made up of mineral matter, and it is called OLIVINE(magnesium and iron silicate) which comprises a basic rock variety called DUNITE a rock which maybe in glassy state.
3.THE CRUST: The crust is the outer most of the concentric earth zones. It is a shell of regular thickness with an average thickness of 35kms. The crust consist of two zones with contracting dominant rock types.
i. A Lower Basoltic Zone: this is composed of dark and heavy rocks consisting mainly of basolt and related rock types with a density of about 2.8 to 3.0gram and still heavier ultra basic rocks(density up to 3.4grams).
Silica is the most abundant constituent of this rocks while iron oxide and magnisia,either single or together. The whole group is known by the term "SIMA".
ii. OUTER GRANITE ROCK:this is composed of light rocks including granite and rated rocks which have an average density of about 2.7grams.The rocks are collectively know as "SIAL".
The mantle is enveloped by the crust and separated from it by a major discontinuity zone known as the "mohorovicic discontinuity" or briefly as Moho discontinuity.This boundary was discovered in 1909 by a Croatian is irregularly covered by a sedimentary layer which varies in depth from zero in some places to a maximum depth of about 9,150meters in some depressions and river valleys.



