2. Learning outcomes
❖ Describe the compositional and the structure layers of the Earth’s
interior.
❖ Discuss the Structural Zones of the Earth's Interior.
❖ List the characteristics of Earth’s four major spheres
❖ Identify the two main sources of energy in the Earth system.
3. The Earth Crust
The Earth’s Crust is the thinnest layer on the Earth 5- 100 km.
There are two types of crust
❖ Oceanic crust- made mostly of the igneous rock basalt. Found under the
ocean. Contains more iron than the continental crust, therefore it’s more
dense.
❖ Continental crust- made mostly of granite.
4. Special Parts of the Crust
Lithosphere
❖ Crust is the upper part of the lithosphere
❖ Broken up into the large plates
❖ The uppermost part of the mantle is also part of the lithosphere
Asthenosphere
❖ Upper part of the mantle, below lithosphere
❖ Cooler part of the mantle that the lithospheric plates slide on the top[
5. The Earth’s Mantle
❖ Located directly above the outer core
❖ Starts below the crust
❖ Is the largest layer
❖ 80% of the Earth’s volume & 68% of the Earth’s mass
❖ Composed of more iron than the crust.
❖ Density, pressure, and temperature all increase the deeper you
go to the mantle.
❖ Temperature ranges from 870c- 2000c (1598F-3632F)
7. The Earth Core
❖ Composed of the inner and outer core
❖ Both are made of iron and Nickel
8. The Earth’s Core
The Outer Core
❖ Liquid surrounds the inner core
❖ Temperature ranges 3992F~ 9032F
The Inner Core
❖ Temperature reaches 9032F
❖ Solid iron and nickel
❖ Usually both would be liquid but are solid in the core because of pressure
❖ The solid core is the source of Earth’s magnetic field.
9. Magnetosphere
❖ The inner core and outer core do not turn at the same
speed as the rest of the earth.
❖ Causes a generator effect which produces a magnetic
field.
❖ It protects us from some of the sun’s harmful radiation.
11. Alpha Decay
An Alpha particle is identical to that of a helium
nucleus
It contains two protons and two neutrons
12. Beta Decay
As a result of beta decay, the nucleus has one less neutron but
one extra proton. The atomic number, Z increases by 1 and the
mass number, A stays the same
13. Gamma Decay
Gamma rays are electromagnetic radiation with frequency.
When atoms decay by emitting (A) or (B) particles to
form a new atom, the nuclei of the new
atom formed may still have
too much energy to be completely stable.
14. Causes of Convection Currents
❖ Pressure and Temperature
❖ Density
❖ Cooling
❖ Earth’s rotation