UNIT 3-geosphere-1eso.pptx Biology & Geology Bilingual program

1. UNIT 3
THE GEOSPHERE,
MINERALS AND ROCKS
INDEX
1. Studying the earth’s interior
2. The layers of the geosphere
3. Minerals and rocks
4. The properties of minerals
5. Rocks
6. Use of minerals and rocks

2. VOCABULARY
POINT 1
• Drill holes
• Seismic
• Seismic waves
• Seismograph
• Speed
POINT 2
Crust
Mantle
Core
Molten
Outer
Inner
POINT 3
• Chemical
• Formula
POINT 4
 Lustre
 Dull
 Waxy
 Glassy
 Hardness
 Cleavage
 Streak
POINT 5
 Weathering
 Melting
 Cooling
 Igneous
 To beat
 To sink
 Layer
 Molten
 To rise up
 Towards
 Reaching
 To be subjected to
 Slate
 Mable
POINT 6
 Plaster
 Lead
 Native metal
• Sondeo
• Sísimico
• Ondas sísmicas
• Sismógrafo
• Velocidad
• Corteza
• Manto
• Núcleo
• Fundidas
• Externo
• Interno
• Química
• Fórmula
• Meteorización
• Fusión
• Enfriado
• Ígneas
• Golpear
• Hundir
• Capas
• Fundido
• Elevar
• Hacia
• Alcanzando
• Estar sujeto a
• Pizarra
• Mármol
• Escayola
• Plomo
• Metal nativo
•Brillo
•Mate
•Ceroso
•Vítreo (cristalino)
•Dureza
•Exfoliación
•Raya

3.  The Earth is 6370 km at the Equator but we only
have direct knowledge of the most superficial
layers under the Earth’ s surface.
 Mines or drill holes have allowed us to reach
depths of 8 -12 km.
 To understand the composition of the Earth’ s
interior, scientists have to use indirect methods.
1. STUDYING THE EARTH’S
INTERIOR
drill holes

4.  This method analyses the energy generated by
earthquakes.
 When an earthquake occurs, the movement
generates waves of energy that travel to the
interior of the Earth, called seismic waves.
 These waves can be detected by an apparatus
called a seismograph.
 This shows us that the speed of the waves vary
as they pass from one layer to another.
 The study of the data obtained from
seismographs has allowed scientists to deduce
the composition of the Earth’ s interior.
1. STUDYING THE EARTH’S
INTERIOR
INDIRECT METHODS
 The most common method is the study of earthquakes called the seismic
method. /saɪzmɪk/

5. 2. THE LAYERS OF THE
GEOSPHERE
 The GEOSPHERE has
three concentric layers:
 CRUST: It’s made up of
solid and hard rocks.
It’s divided into:
 Continental crust
 Oceanic crust
 MANTLE: It’s made up of
denser rocks than the
crust’s rocks.The rocks in
the upper part are hard, but
in other zones they can be
molten.
 CORE: It consists of two
parts: OUTER CORE
(molten) and INNER CORE
(solid).
(Crust-Mantle)
(Mantle-Core)

6. http://www.oum.ox.ac.uk/thezone/minerals/define/quiz/index.htm
3. MINERALS AND ROCKS
Minerals: They are substances that have to be:
Solid at room temperature. They cannot be
liquids or gases.
Inorganic, they cannot be formed by living
beings.
Defined chemical composition, they are
formed by one or more elements in a certain
proportion that we can express with a chemical
formula.
Natural origin, that is to say, they are not
made up by humans.
• The terrestrial crust is formed by different materials.
• The most important ones are minerals and rocks.
Rocks: They are solid
substances formed by
the combination of
minerals.

7. 3. MINERALS AND ROCKS
3.1. Look at the chart below and indicate why these substances cannot be
considered minerals.
Substance
State
(at room
temperature) Inorganic
Chemical
composition Natural origin
Water Liquid Yes H2O Yes
Mercury Liquid Yes Hg Yes
Bone Solid No Ca 3(PO4) 2 Yes
Plastic Solid Yes Undefined No
3.2. What is the difference between a mineral and a rock?

8. 4. PROPERTIES OF MINERALS
 They are physical characteristics that can be observed and determined in a
simple way. The chemical composition and the disposition of the atoms influence
many physical properties:
1. HARDNESS:
It is the resistance that the mineral has to being scratched.
To define the hardness of a mineral we use the MOSH SCALE OF HARDNESS.
Page 31
Ex. 5 & 6

9. Mohs Scale Hardness Hardness of Common
Objects
Talc (softest) 1 Fingernail 2.5
Gypsum 2 Piece of copper 2.5-3.0
Calcite 3 Iron nail 4.5
Fluorite 4 Glass 5.5
Apatite 5 Steel file 6.5
Feldspar 6 Streak plate 7.0
Quartz 7 Flint sandpaper
Topaz 8 Spinel (rock shops)
Corundum 9 Emery sandpaper
Diamond
(hardest)
10 Carborundum sandpaper
LOW
HARDNESS
HIGH
HARDNESS
MEDIUM
HARDNESS
http://mundo-
mineral.blogspot.com.es/search/label/Mag
netita

10. 4. PROPERTIES OF MINERALS
2. COLOUR:
It depends on the light that is absorbed or reflected by the mineral.
• Some mineral have always the same color, but others can be different colors
because small differences in their chemical composition, such as quartz.
white or
transparent
halite
different
colours
quartz
waxy
talc
dull to glassy
feldspars
metallic
pyrite
glassy
quartz
3. LUSTRE: /lʌstəʳ/
The way a mineral reflects light.

11. 4. PROPERTIES OF MINERALS
4. CLEAVAGE
This is how a mineral breaks up.
muscovite
Mica cleaves in sheets.
Galena cleaves into small
Cubes.

12.  The earth´s crust is made of rocks.
 Rocks are aggregates of mineral particles.
 According to the origin of the rocks, geologists classify them into:
1. Metamorphic rocks
2. Igneous rocks
3. Sedimentary rocks
http://www.bbc.co.uk/bitesize/ks3/scien
ce/environment_earth_universe/rock_cy
cle/activity/
both types considered to result from
internal processes (internal dynamics of
the Earth)
Derived from external processes
(extenal dynamics of the Earth).
5. ROCKS

13. SEDIMENTARY ROCK
IGNEOUS ROCK
METAMORPHIC ROCK
weathering
and
erosion
compaction
and
cementation
melting
cooling
SEDIMENTS
MAGMA
http://www.students.linguaframe.com/04b-
rocks
5. ROCKS

14. Formation of sedimentary rocks
Wind and moving water
beat away fragments of
rocks and transport them.
The fragments sink to
the sea floor as
sediment. Over time
they build up and
form layers.
When many layers are formed, the
lower layers of sediment are
compacted by the upper layers
and are transformed into
sedimentary rocks.
1 2
3
Limestone
Examples of sedimentary rocks
Conglomerate Sandstone
5. ROCKS A. SEDIMENTARY
ROCKS

15. Formation of magmatic rocks
Magma (very hot
masses of molten
minerals) rises up slowly
through the lithosphere
towards the Earth’s
surface.
The magma that
reaches the surface
through volcanoes
cools down quickly and
forms VOLCANIC
ROCKS.
The magma that does
not reach the surface
cools down slowly
and forms
PLUTONIC ROCKS.
1 2 3
http://recursos.cnice.mec.es/biosfera/alumno/2ESO/tierrin/actividades/rocas1.htm
http://recursos.cnice.mec.es/biosfera/alumno/2ESO/tierrin/actividades/act16.htm
http://roble.pntic.mec.es/~hotp0039/jaznar/Hibrida.htm
5. ROCKS B. IGNEOUS
ROCKS
GRANITE
BASALT

16.  They are created from rocks which are crushed (high pressures) and/or
exposed to high temperatures inside the crust, but they DON’T MELT.
Some rocks inside the
lithosphere are subjected to
great pressures and high
temperatures.
High pressure and temperatures cause
changes in these rocks that turn them
into metamorphic rocks.
1 2
5. ROCKS C. METAMORPHIC ROCKS
SLATE GNEISS
MARBLE

17. 6. USES OF MINERALS AND ROCKS
Minerals are used in:
• MEDICINE: Gypsum to make plaster.
• CONSTRUCTION:
 Metals such as iron (Fe) and lead (Pb),
 calcite to make cement,
 quartz to make glass and electrical components.
• JEWELLERY: Gems as diamonds or native metals, such as gold and silver.
USE OF MINERALS

18. 6. USES OF MINERALS AND ROCKS
Rocks are used in:
• CONSTRUCTION:
 Clay to make bricks and ceramics
 Stones
 Marble and granite for urban furniture and sculptures
• ENERGY PRODUCTION: Coal and oil.
• PLASTICS: Produced from oil.
USE OF ROCKS