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BCLN Science 7 - Rev. Sept/2015
Unit 7 ~ Learning Guide Name: ______________________________
Instructions:
Using a pencil, complete the following notes as you work through the related lessons. Show ALL work as is explained in the lessons. You are required to have this package completed BEFORE you write your unit test. Do your best and ask questions if you don’t understand anything! Minerals Questions
1. What does the word rock refer to?
2. What are 3 properties of minerals?
3. What conditions are necessary to form solid mineral deposits?
4. What are the three classifications of rock groups?
5. Complete the following table on mineral properties. The first one is done for you.
Property
Colour
Streak
Lustre
Hardness
Description
- The visible colour of the mineral.
- 2 minerals may have same
colour.
2 Examples
- Gold is yellow
- Jade is green
BCLN Science 7 - Rev. Sept/2015
Crystal Structure
Cleavage
Magnetism
Reaction with
certain
chemicals
Rock Families Questions
1. Define the following terms.
Term
Magma
Intrusive Igneous
Rock
Lava
Extrusive
Igneous Rock
Sediment
Definition
BCLN Science 7 - Rev. Sept/2015
2. How are each of the three rock families formed? Give two examples for each rock family,
describe how each specific example is formed, and one of its uses.
Igneous Rock
How it is formed:
Example 1:
Example 2:
Sedimentary Rock
How it is formed:
Example 1:
Example 2:
Metamorphic Rock
How it is formed:
Example 1:
Example 2:
BCLN Science 7 - Rev. Sept/2015
3. Draw and label a diagram about the formation of each rock family.
Igneous Rock
Sedimentary Rock
Metamorphic Rock
Fossils Questions
1. How are Fossils formed?
2. Write the steps in the correct order for the formation of cast fossils.
-The organism is buried in sediment
-An organism dies
-Water dissolves the organism
-Minerals in the organism are replaced by minerals in the water.
-The sediment becomes compacted by other layers of sediment.
1.
2.
3.
4.
5.
3.
What are three pieces of evidence of changes in the Earth have scientists found in the
Burgess Shale?
BCLN Science 7 - Rev. Sept/2015
Weathering Questions
1. What is weathering?
2.
Explain the difference between each type of weathering and provide an example for each
one.
Mechanical
Weathering
Chemical Weathering
Biological Weathering
Explain:
Explain:
Explain:
Example:
Example:
Example:
Erosion Questions
1. What is erosion?
2. What is deposition and how does it work?
3. Give an example of each type of erosion.
Type or Erosion
Gravity
Wind
Water
Ice
Example
BCLN Science 7 - Rev. Sept/2015
Rock Cycle Questions
1. Use the diagram of the rock cycle on lesson 7.8 to explain the following. Be sure to use
vocabulary from the legend and the diagram (such as melting and magma).
How an igneous rock becomes a sedimentary rock.
How an igneous rock breaks down and becomes an igneous rock again.
How a sedimentary rock becomes n igneous rock.
BCLN Science 7 - Rev. Sept/2015
Answer Key
Minerals Answers:
1. The word rock refers to solid mineral deposits.
2. 1) Minerals are not classified as animals or vegetables, 2) can be metal ores, 3) can be nonsolid (gas or liquid)
3. Pressure, temperature, erosion, and friction are forces that effect the formation of rocks.
4. The three rock groups are igneous, sedimentary, and metamorphic.
5.
Property
Colour
Streak
Lustre
Hardness
Crystal Structure
Cleavage
Magnetism
Reaction with certain
chemicals
Description
- The visible colour of the mineral. - 2
minerals may have same colour.
2 Examples
- Gold is yellow
- Jade is green
-rub a mineral across a porcelain tile it
leaves a coloured streak
-streaks can be different colours from the
mineral
-the way the mineral reflects light
-metallic lustre (very shiny), non-metallic
lustre (waxy, pearly, silky)
-measured by scratching a mineral
-measured using Mohs hardness scale 1
(soft) to 10 (hard)
-all minerals are made of crystals
-the crystals have different sizes, shapes,
flat, and straight edges
-Halcite leaves a reddish streak
-minerals harder than 7 will not
leave a streak
-the way a rock breaks apart can tell you
about it
-if it breaks apart smooth surfaces it has
cleavage, jagged edges are called
fractures
-minerals that contain iron will be
attracted to a magnet
-some minerals will react with different
chemicals
-produce bubbles or produce gas
-gold (metallic lustre)
-jade (non-metallic lustre)
-quartz (7 for hardness)
-talc (1 for hardness)
-Halcite has cubic crystals
-Pyrophyllite has star-like crystals
-mica and biotite splits across flat
surfaces
-obsidian fractures along jagged
edges
-magnetite is magnetic
-limestone, and calcite produces
bubbles or fizz when mixed
with vinegar
BCLN Science 7 - Rev. Sept/2015
Rock Families Answers:
1.
Term
Definition
Magma
A hot semifluid liquid from the within the earth's crust. Forms lava and
igneous rock when cooled.
If the rocks are cooled below Earth's surface they are called intrusive igneous
rocks.
Hot molten or semifluid rock erupted from a volcano or fissure, or solid rock
resulting from cooling of this.
If the rocks are cooled above the Earth's surface they are called extrusive
igneous rocks.
Intrusive Igneous
Rock
Lava
Extrusive Igneous
Rock
Sediment
Little pieces of our earth have been eroded--broken down and worn away by
wind and water.
2.
Igneous Rock
How it is formed: It is formed underground or above ground by cooling magma (liquid rock from
volcanoes).
Example 1: Granite is a combination of quartz, feldspar, mica, and usually hornblende. Granite forms as
magma cools far under the earth's surface. Granite is an excellent material for building.
Example 2: Obsidian cools when lava cools quickly above ground. It is used as a scalpel by doctors in very
sensitive eye operations.
Another example is pumice.
Sedimentary Rock
How it is formed: It is formed by pieces of the earth slowly eroding and breaking into smaller pieces. These
pieces are called sediment. The sediment washes downstream and settles in lakes and streams. It is
cemented together with dissolved minerals.
Example 1: Shale is sand that gets compressed in slower moving waters to form thin layers. It is generally
used to make brick.
Example 2: Sandstone is compressed layers of sand. Pressure from materials on top cause it to compress
and it is cemented together with minerals. It is used as a building material.
Another example of a sedimentary rock is conglomerate.
Metamorphic Rock
How it is formed: It was once a sedimentary or igneous rock that changed forms. They change because of
pressure and heat. Many mountain ranges are made up of metamorphic rocks.
Example 1: Slate started out as shale and heat and pressure turned it into slate. It is often used in roofing
tiles.
Example 2: Marble was limestone that changed because of heat and pressure. It is used as a building
material, for countertops, and statues.
Another example of a metamorphic rock is Gneiss.
BCLN Science 7 - Rev. Sept/2015
3.
Igneous Rock
Sedimentary Rock
Metamorphic Rock
Metamorphic Rock
Sediments
Magma
Fossils Answers:
1. Fossils are formed when the remains of an animal or plants are buried before they can be
destroyed, and if the conditions are just right, the organism's remains get preserved as
fossils.
2.
1. An organism dies.
2.The organism is buried in sediment
3.Water dissolves the sediment
4.Minerals in the organism are replaced by minerals in the water
5.The sediment becomes compacted by other layers of sediment
3. 1. Evidence of climate changes, 2. Determine the history and age of the rocks in which they
are found, 3. Tell us about organisms that existed on Earth 500 million years ago, 4. The
fossil evidence, or fossil record, scientists can determine how life on Earth has changed over
time, 5. Fossils of sea animals found inland may be evidence that the ocean once covered
that area.
Weathering Answers:
1. The process of breaking down natural materials (such as rocks) into smaller pieces, is called
weathering.
BCLN Science 7 - Rev. Sept/2015
2.
Mechanical Weathering
Explain: mechanical (or
physical) forces
Example: Water seeped into
cracks in a rock. It expanded
when it froze and forced the rock
apart.
A glacier has moved over a rock,
causing gouges to be cut into it.
They can also cut deep valleys
with steep sides.
Chemical Weathering
Explain: caused by chemical
reactions
Example: Acidic water has
dissolved limestone to form a
cave.
When rock that contains iron is
oxidized a reddish-brown rust
appears.
Biological Weathering
Explain: caused by a living
organism
Example: Lichen growing on this
rock produces an acid that will
wear down the rock.
The roots from this tree have
forced the surrounding rocks to
break apart.
Erosion Answers:
1. In time (sometimes quickly and sometimes over large amounts of time), weathered rock gets
moved and spread out. The movement of this weathered rock is called erosion.
2. All types of erosion carry bits of soil, dirt, and rocks which is then dropped in a new place.
This dropping of sediment is called deposition.
3.
Type or Erosion
Gravity
Wind
Water
Ice
Example
Landslides and avalanches are caused by gravity. Landslides are quite common in
British Columbia.
Wind is responsible for moving sand and soil many miles. The prairies and desert
areas are prone to sandstorms.
Like most canyons and valleys, the Grand Canyon was carved out by water over
millions of years.
Glaciers are large bodies of ice that move slowly downhill carrying rocks and soil
with them.
Rock Cycle Answers:
1.
How an igneous rock becomes a sedimentary rock.
-the igneous rock undergoes weathering and erosion, it becomes pieces of sediment, it carries downstream,
into lakes and rivers, sediments become buried and solidify
How an igneous rock breaks down and becomes an igneous rock again.
Igneous rock undergoes melting to become magma, the magma hardens to become igneous rock again.
How a sedimentary rock becomes n igneous rock.
-a sedimentary rock melts and becomes magma, it then