Earth Science

Grade 7

Chapter 3: Minerals

Vocabulary

• Mineral- 4,000 minerals are naturally occurring inorganic solids with a definite structure and composition.

• Crystal- is a solid in which the atoms are arranged in repeating patterns.

• Magma- cooling of hot melted rock material.• Silicate- materials that contain silicon and

oxygen.

Mineral IdentificationTest Description

Appearance Observe - What does it look like?

Hardness Mohs scale 1-10 (talc is the softest - 1; diamond is hardest – 10)

Luster How well does it reflect light? Metallic shiny, non-metallic is dull.

Color Distinct; yellow for sulfur and purple for amethyst

Streak Color left on tile

Cleavage Smooth break like mica

Fracture Rough break like quartz

Other Tests Smell, Magnet, Acid Test, Double Refraction

Uses of Minerals• Gems-rare, beautiful, highly prized minerals• Ores-mineral mined for a profit• Titanium-Strong, lightweight, nontoxic ore

that can be used in airplanes, artificial body parts, sporting equipment, wheelchairs, etc.

Other Uses of Minerals

Chapter 4- Rocks• Rock-mixture of minerals, mineraloids, glass or organic matter• Rock Cycle- a continuous dynamic process where one rock changes

to another • Processes of the Rock Cycle• Weathering-breaking of rocks into smaller pieces, either

mechanically or chemically• Erosion-the process that wears away surface materials and moves

them from one location to another, usually by gravity, glaciers, wind, or water.

• Compaction-pressing sediments of rock together• Cementation-sediments naturally being glued together• Sediments-made from loose rock fragments

Igneous Vocabulary

• Igneous Rock-most abundant rock on Earth because its inside and outside the earth, formed from magma and lava

• Intrusive-forms inside the earth from magma• Extrusive-forms outside the earth from lava• Granitic-light colored, light weight, low density rocks

like Pumice and Granite (Silicon,Oxygen)• Andesitic-medium color and density• Basaltic-dark colored, heavy rich in Iron and

Magnesium

Igneous Rock Examples

GranitePumice

Obsidian

Scoria

Metamorphic Rocks

• Metamorphic-rocks that have changed due to heat and pressure

• Foliated-rocks with parallel lines • Nonfoliated-rocks with out parallel lines

Metamorphic Rock Examples

Slate Marble

Gneiss Quartzite

Sedimentary Rocks

• Sedimentary Rocks-form when sediments get pressed or cemented together

• Organic-made from the remains of once living things

• Detrital/Clastic-made from broken rock fragments

• Chemical-when minerals precipitate out of a solution

Sedimentary Rock Examples

Shale Limestone

Coquina Sandstone

Coal

Conglomerate

Chapter 5-Views of the Earth

Landforms:• Plains- large relatively flat areas of land, good

for grazing and crops• Plateaus-a relatively raised flat area of land• Mountains-rise above surrounding land• Examples-folded, volcanic, up warped, and

fault-block

Landform Examples

Plains Plateau Mountains

Viewpoints

• Equator-imaginary point that separates the Northern and Southern hemispheres

• Prime Meridian-line that separates the Eastern and Western Hemispheres

• Latitude-tells us degrees north or south of the equator

• Longitude-tells us degrees east or west of the prime meridian

• Time Zones-6 times in the United States, 24 Time Zones in the World

Viewpoints

Globe Equator and Prime Meridian

WEATHERINGChapter 6

Types of WeatheringMechanical Weathering Chemical Weathering

Breaks rocks apart without changing chemical composition

Chemical composition of the rock changesWater & Oxygen are factors

Examples:

-Plant roots grow into the cracks of rocks-Animals Burrowing-Ice Wedging

Examples:

-Acid Rain-Rust

Sediments + Organic Matter = Soil• Soil-

• Humus-

• Soil Profile-

• Horizon-

• Leaching-

Layers of Soil

Process

of

Soil Formation

Process

of

Soil Formation

Chapters 7 & 8

Erosion ForcesDeposition

Erosion Words to Know

• Erosion

• Deposition

• Mass Movement

• Slump

• Creep

More Erosion Words to Know

• Glacier

• Plucking

• Till

• Moraine

And More Erosion Words to Know

• Deflation- • Abrasion-

• Loess-

Chapter 11

Plate Tectonics

Continental Drift

• Continental Drift

• Pangaea

Evidence Supporting Continental Drift

Climate Clues Rock Clues Fossil Clues

Fossils of warm weather plants found in typically cold climates, Antarctica could have been closer to the equator at Pangaea time

Similar rock structures on different continents , East coast of South America and West Coast of Africa

Fossil remains found on different continents , dinosaurs could not swim across the ocean,

ex. Mesosaurus

Seafloor Spreading• Seafloor Spreading-

• Magnetometer-

• Age Evidence-

Theory of Plate Tectonics

• Plate Tectonics-

• Plate-

• Lithosphere-

• Asthenosphere-

Plate BoundariesDivergent Boundary Convergent Boundary Transform Fault Boundary

Plates divide, move apart Plates collide Plates slide past each other

Ex. Mid-Ocean Ridge Ex. India crashed into China to create the Himalayan Mountain Range

Ex. San Andreas Fault in California

Cause of Plate Tectonics

• Convection Currents-

• Effects of Plate Tectonics-

Ch. 9- Earthquakes

Forces Inside Earth

• Fault-

• Earthquake-

Types of FaultsNormal Fault Reverse Fault Strike-Slip Fault

Plates move apart, Tension

Compression crash into each other

Rocks move past each other

Ex. Mid Ocean Ridge

Ex. Rocky Mountains

Ex. San Andreas Fault

Aka Divergent Boundary

Aka Convergent Boundary

Aka Transform Fault Boundary

Earthquake Information• Seismic waves-

• Primary Wave-

• Secondary Wave-

• Focus-

• Epicenter-

Draw & label the parts of an earthquake.

Include the following:

focus, epicenter, fault, primary wave, secondary wave, surface wave

Earth!• Inner core-

• Outer core-

• Mantle-

• Crust-

• Moho discontinuity-

Compare the layers of earth to an apple!

Earthquake Destruction

• Seismologist-

• Seismograph-

• Magnitude-

Ocean waves generated by earthquakes are called seismic sea waves, or tsunamis.

What is A Volcano?

• A VOLCANO is an opening in Earth’s surface that often forms a mountain when layers of lava & ash erupt

• After many thousands or even millions of years, magma reaches earth’s surface and flows out through an opening called a VENT.

Magma vs. Lava

Draw & Label the Parts of A Volcano

Where do volcanoes occur?

1. Where plates move APART

AKA: Divergent plate boundaries

1. Where plates move TOGETHER

AKA: Convergent plate boundaries

Where do volcanoes occur?

3. HOT SPOTS areas of earth that

melt rock & force magma upward

Pacific Ring of Firearea around the pacific plate where earthquakes & volcanoes are common

Active vs. Dormant• Most of Earth’s volcanoes are DORMANT, which

means they are not currently active

• There are more than 600 active volcanoes in the world

• The most active volcano in the world is Kilauea in Hawaii

Brain Pop

http://www.brainpop.com/science/earthsystem/volcanoes/

Quick Review!

1. I am an opening in earth’s surface that often forms a mountain when lava & ash build up

2. I am an opening through which magma flows

3. I am an area around the Pacific Plate where earthquakes & volcanoes are common

Label the Volcano!

Don’t Forget:

Vent

Crater

Lava

Types of Volcanoes

A volcano’s form depends on whether it is the result of a quiet or an explosive eruption.

TYPE 1: SHIELD VOLCANO

• Broad volcano• Gently sloping sides

Hawaiian Islands

TYPE 2: CINDER CONE VOLCANO

• Explosive eruptions throw lava into the air• Lava then cools & hardens into TEPHRA

- steep sides- loosely consolidated

Paricutin, Mexico

TYPE 3: COMPOSITE VOLCANO

• Vary between quiet & explosive eruptions• Lava & tephra is repeated over & over

Mount Saint Helens

Websites!

• www.brainpop.com• Kids.nationalgeographic.com• www.mineralogy4kids.org • www.geology4kids.com • www.geography4kids.com