Chapter 9 Rocks

Question 1

what all rocks are made of

Answer 1

minerals

Question 2

the outermost layer of the Earth, includes the crust and uppermost part of the mantle

Answer 2

lithosphere

Question 3

a very hot mixture of molten rock and gases, just below the Earth’s surface, that has come from the mantle

Answer 3

magma

Question 4

material broken down by weathering and erosion that is moved by wind or water and collects in layers

Answer 4

sediments

Question 5

elements found uncombined in the Earth’s crust

Answer 5

native elements

Question 6

substance made up of atoms and molecules arranged in one of seven different shapes.

Answer 6

crystals

Question 7

appearance of a mineral caused by the way it reflects light. A mineral can appear glassy, waxy, metallic, dull, pearly, silky or brilliant.

Answer 7

lustre

Question 8

colour of a mineral as a fine powder, found by rubbing it onto an unglazed white ceramic tile

Answer 8

streak

Question 9

a measure of how difficult it is to scratch the surface of a solid material. The hardness rating of a mineral is determined by comparison with ten standard minerals. Diamond has a hardness rating of 10 and can scratch other minerals with a lower hardness rating.

Answer 9

hardness

Question 10

eroding or being eroded by wind, water, or other natural agents.

Answer 10

erosion

Question 11

denoting rocks composed of broken pieces of older rocks.

Answer 11

clastic

Question 12

interactions of substances as studied in chemistry.

Answer 12

chemical

Question 13

relating to or derived from living matter.

Answer 13

organic

Question 14

the remains or impression of a prehistoric plant or animal embedded in rock and preserved in petrified form.

Answer 14

fossils

Question 15

rocks that form from the cooling of lava or magma as it is thrown through the air from a volcanic eruption

Answer 15

igneous rocks

Question 16

igneous rock that forms when lava cools above the Earth’s surface

Answer 16

extrusive rocks

Question 17

a pale rock that forms when frothy lava cools in the air. Pumice often floats on water as it is very light and full of holes that once contained gas.

Answer 17

pumice

Question 18

a dark, igneous rock formed from gassy lava that cools quickly

Answer 18

scoria

Question 19

a property of a material or substance that easily scratches another

Answer 19

abrasive

Question 20

a dark, igneous rock with small crystals formed by fast cooling of hot lava. It sometimes has holes that once contained volcanic gases.

Answer 20

basalt

Question 21

a black, glassy rock that breaks into pieces with smooth shell-like surfaces

Answer 21

obsidian

Question 22

igneous rock that forms when magma cools below the Earth’s surface

Answer 22

intrusive rocks

Question 23

intrusive rock mass that measures more than 100 kilometres across

Answer 23

batholiths

Question 24

a hard, igneous rock with different-coloured crystals large enough to see. It forms slowly below the Earth’s surface.

Answer 24

granite

Question 25

flat, open land beside a river where sediments are deposited during floods

Answer 25

floodplains

Question 26

large bodies of ice that move down slopes and push boulders, rocks and gravel in front of them

Answer 26

glaciers

Question 27

deposit left by movement of a glacier

Answer 27

moraines

Question 28

a sedimentary rock with medium-sized grains. The sand grains are cemented together by silica, lime or other salts.

Answer 28

sandstone

Question 29

a fine-grained, sedimentary rock without layering

Answer 29

mudstone

Question 30

a fine-grained sedimentary rock formed in layers by the consolidation of clay

Answer 30

shale

Question 31

a sedimentary rock with a particle size between that of sandstone and mudstone

Answer 31

siltstone

Question 32

sedimentary rock containing large particles of various sizes cemented together

Answer 32

conglomerate

Question 33

a sedimentary rock formed from the remains of sea organisms. It consists mainly of calcium carbonate.

Answer 33

limestone

Question 34

a sedimentary rock formed from dead plants and animals that were buried before rotting completely

Answer 34

coal

Question 35

a sedimentary deposit formed when a salt lake or seabed dried up. Its main chemical is sodium chloride.

Answer 35

rock salt

Question 36

the process that changes rocks by extreme pressure or heat (or both)

Answer 36

metamorphism

Question 37

rock formed from another rock that has been under great heat or pressure (or both)

Answer 37

metamorphic rocks

Question 38

a fine-grained metamorphic rock formed as a result of moderate heat and pressure on shale

Answer 38

slate

Question 39

a metamorphic rock formed as a result of great pressure on limestone

Answer 39

marble

Question 40

a coarse-grained metamorphic rock formed mainly as a result of great pressure on granite

Answer 40

gneiss

Question 41

rocks mined to obtain a metal or other chemical within them

Answer 41

mineral ores

Question 42

extraction of natural resources from the Earth

Answer 42

mining

Question 43

study of the possible effects of a planned project on the environment

Answer 43

environmental impact statement (EIS)

Question 44

restored to its previous condition

Answer 44

rehabilitated

Question 45

waste rock removed from below the topsoil. This rock is replaced when the area is restored.

Answer 45

overburden

Question 46

mining that scours out soil and rocks on the surface of the land

Answer 46

open-cut mining

Question 47

mining that uses shafts and tunnels to remove rock from deep below the surface

Answer 47

underground mining

Question 48

any remains, impression, or trace of an animal or plant of a former geological age; evidence of life in the past

Answer 48

fossil

Question 49

the buckling of rocks. It is caused when rocks are under pressure from both sides.

Answer 49

folding

Question 50

a scientist who studies fossils

Answer 50

palaeontologists

Question 51

the age of a rock compared with the age of another rock

Answer 51

relative age

Question 52

animal that eats other animals

Answer 52

carnivores

Question 53

animals that eat dead plant and animal material

Answer 53

scavengers

Question 54

cavity in a rock that shows the shape of the hard parts of an organism; types of fungi found growing on the surface of foods

Answer 54

mould

Question 55

fossils that provide evidence, such as footprints, that an organism was present when the rock was formed

Answer 55

trace fossils

Question 56

describes volcanoes that are no longer active. Extinct volcanoes have not erupted for thousands of years and show no sign of future eruption.

Answer 56

extinct

Question 57

a law that states that energy cannot be made or lost. However, energy can be transformed from one type to another or transferred from one object to another.

Answer 57

Law of Conservation of Energy

Question 58

the energy made available by the flow of electric charge through a conductor

Answer 58

electrical energy

Question 59

energy stored due to the height of an object above a base level

Answer 59

gravitational potential energy

Question 60

potential energy derived from chemical reactions

Answer 60

chemical energy

Question 61

the potential energy stored in a stretched elastic material

Answer 61

elastic potential energy

Question 62

the energy stored at the centre of atoms, the tiny particles that make up all substances. Nuclear energy can be released from the radioactive metals uranium or plutonium, and transformed into electrical energy in a nuclear power station.

Answer 62

nuclear energy

Question 63

the fraction of energy supplied to a device as useful energy. It is usually expressed as a percentage.

Answer 63

efficiency

Question 64

releasing its own light

Answer 64

luminous

Question 65

describes objects that emit light when they are hot

Answer 65

incandescent

Question 66

describes living things that release light energy

Answer 66

bioluminescent

Question 67

describes light sent in many directions by small particles within a substance

Answer 67

scattered