Exploring Our Beloved Earth

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

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

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

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

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).

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

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.

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

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

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

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

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

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

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. www.soc.soton.ac.uk

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.

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.

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.

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

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

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.

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