Geography [1 Mark Question Answer]

Moho Discontinuity is the boundary between crust and mantle and Gutenberg Discontinuity is the boundary between mantle and core.

At the depth of 100 – 250 km. The mantle is partially molten and known as asthenosphere, with a temperature of 1100°C.

Mantle lies between 60 – 2900 km. depth. It is divided into two parts namely upper mantle and lower mantle, which are in the form of solid rocks and semi-molten rocks respectively.

The crust is made of solid rocks and divided into oceans and continents.

The crust is called Lithosphere made of solid rocks with a thickness of 60 km. below high mountains and 6-12 km below the oceans.

NiFe is composed of Nickel (Ni) and Iron (Fe), being heavy metals and having high density, these are found deep inside the earth.

NiFe is found in the inner core of die earth.

Geology is the science dealing with the origin and types of rocks found in the interior of the earth.

The Mantle or Mesosphere is located between 2850 – 2900 km beneath the earth crust.

The Earth is not a perfect sphere. It is slightly flattened at both the poles. It is due to the centripetal force produced by the rotation of the Earth.

Oxygen and Silicon.

‘Nife’ means Nickel (Ni) and Iron (Fe) due to the majority of Nickel and Iron in the core.

Sima is the second layer of earth which gives support to the ocean beds. There is the excess of Silica and Magnesium.

Sial is the upper layer or crust of the earth. The name Sial is based on the excess of Silica and Aluminium. The depth of Sial is 60 km.

The high pressure in the interior core keeps this layer firm and solid in some parts, in spite of the temperature as high as 5000°C.

At the depth of 100 – 250 km the mantle is partially molten and known as asthenosphere due to the temperature around 1100°C along with greater pressure and density.

Due to enhancing density and pressure the temperature goes on increasing gradually towards inside of the interior of the earth.