1. Exploring Our Beloved Earth

2. Earth’s Parts are open systems
interact by exchanging matter and energy
**Planet Earth is a closed system
Geosphere
Atmosphere
Hydrosphere
Biosphere

6. Earth’s Layers Interior Layers
Crust- loose rocks and soil on earth’s surface
The crust extends as high up as the mountains and as low as the ocean floor
Interior Layers

7. Earth’s Parts Layers of the crust
Lithosphere- solid rock, minerals and soil
Consists of the upper mantle and the crust
Layers of the crust

8. The Lithospheric Plates
The crust of the Earth is broken into many pieces called plates. The plates "float" on the soft, semi-rigid asthenosphere.

9. Earth Stats The Earth's mass is about 5.98 x 1024 kg.
Earth is the densest planet in our Solar System (mass/volume).
Earth is made of several layers with different compositions and physical properties, like temperature, density, and the ability to flow.
MASS, DENSITY, AND ESCAPE VELOCITY The Earth's mass is about 5.98 x 1024 kg. The Earth has an average density of 5520 kg/m3 (water has a density of 1027 kg/m3). Earth is the densest planet in our Solar System. To escape the Earth's gravitational pull, an object must reach a velocity of 24,840 miles per hour (11,180 m/sec).

10. The Structure of the Earth
Lithosphere
Solid
Asthenosphere
Viscous Liquid
The Structure of the Earth
Outer Core
Liquid
Mesosphere
Solid
Core: The Earth has a iron-nickel core that is about 2,100 miles in radius. The inner core may have a temperature up to about 13,000°F (7,200°C = 7,500 K), which is hotter than the surface of the Sun. The inner core (which has a radius of about 750 miles (1,228 km) is solid. The outer core is in a liquid state and is about 1,400 miles (2,260 km) thick.
Inner Core
Solid

11. The Composition of the Earth
The Earth is made of many different and distinct layers. The deeper layers are composed of heavier materials; they are hotter, denser and under much greater pressure than the outer layers.

12. Earth’s Layers Outer core- melted metals, below the mantle
Interior Layers

13. Earth’s Layers
Inner core- solid metal, pressure is so high, liquids are squeezed into solids
Interior Layers

14. The Layers of the Earth
© Copyright 2006.  M. J. Krech. All rights reserved.

15. Lithosphere = ‘rock sphere’
Crust and upper rigid part of Mantle
Asthenosphere = ‘weak sphere’
Upper part of Mantle

16. Earth’s Layers Mantle- below crust, hard but flexible molten rock
Convection currents influence plate movement
Interior Layers

17. The Composition of the Earth
Crust
Thinnest layer (5-100 km)
Two types of crust
Continental
Like granite
Average 30 km
Oceanic
Like basalt
(Basalt is denser than granite!)
Average 5-8 km

18. The Composition of the Earth
Mantle
Extremely Thick! (2,900 km)
It is too far down to drill
How do we know what it is made of?
Scientists infer based on:
Pushed up rock
Ocean floor/molten rock
What is it like?
Like the mineral olivine
Large amounts of iron and magnesium
The Earth is made of many different and distinct layers. The deeper layers are composed of heavier materials; they are hotter, denser and under much greater pressure than the outer layers. Core: The Earth has a iron-nickel core that is about 2,100 miles in radius. The inner core may have a temperature up to about 13,000°F (7,200°C = 7,500 K), which is hotter than the surface of the Sun. The inner core (which has a radius of about 750 miles (1,228 km) is solid. The outer core is in a liquid state and is about 1,400 miles (2,260 km) thick.

19. The Composition of the Earth
Core
Pretty darn big. (6,856 km)
(Slightly bigger than Mars!)
33% mass of the Earth
Scientists think….
Made mostly of iron
Some nickel, sulfur, oxygen
What is the evidence?
The particular way seismic waves travel
Earth’s Magnetic field
The Earth is made of many different and distinct layers. The deeper layers are composed of heavier materials; they are hotter, denser and under much greater pressure than the outer layers. Core: The Earth has a iron-nickel core that is about 2,100 miles in radius. The inner core may have a temperature up to about 13,000°F (7,200°C = 7,500 K), which is hotter than the surface of the Sun. The inner core (which has a radius of about 750 miles (1,228 km) is solid. The outer core is in a liquid state and is about 1,400 miles (2,260 km) thick.

20. The Outer Core
The core of the Earth is like a ball of very hot metals. The outer core is so hot that the metals in it are all in the liquid state. The outer core is composed of the melted metals of nickel and iron.

21. The Inner Core
The inner core of the Earth has temperatures and pressures so great that the metals are squeezed together and are not able to move about like a liquid, but are forced to vibrate in place like a solid.

22. How HOT is it?
Surface of Sun!
5,500°C
Sun Core
15,000,000°C

23. Convection Convection (heat) currents
carry heat from the hot inner mantle to the cooler outer mantle.
The mantle gets warmer with depth
top of the mantle is ~ 1,600° F (870° C)
bottom of the mantle is ~4,000-6,700° F (2,200-3,700° C)
The mantle contains most of the mass of the Earth

25. Assessment One 1. Name Earth’s parts.
2. Describe how Earth’s parts are inter-connected. What are some examples?
3. Describe the Earth’s top two interior layers.

26. The Rock Cycle
Igneous- formed when magma rises to the earth’s surface & hardens
Ex: granite, basalt, pumice, obsidian
Rock Cycle