Topic 2

Question 1

What are the three main types of rocks?

Answer 1

The three main types of rocks are igneous, sedimentary, and metamorphic rocks.

Question 2

How are igneous rocks formed?

Answer 2

Igneous rocks are formed from magma that cools and solidifies. If the magma erupts and cools on the Earth’s surface, it forms extrusive igneous rocks. If it cools inside the Earth, it forms intrusive igneous rocks.

Question 3

What is the difference between extrusive and intrusive igneous rocks?

Answer 3

Extrusive igneous rocks form from magma that cools on the Earth’s surface, while intrusive igneous rocks form from magma that cools inside the Earth.

Question 4

How do sedimentary rocks form?

Answer 4

Sedimentary rocks are formed from sediments that have been deposited at the bottom of lakes, seas, or oceans and compressed over millions of years. These sediments come from eroded rocks carried by rivers or ice, and from the skeletons of sea creatures.

Question 5

What processes lead to the formation of metamorphic rocks?

Answer 5

Metamorphic rocks are formed from existing rocks that are changed by heat, pressure, or chemical processes, usually deep within the Earth.

Question 6

What are the five main layers of rock in Malta?

Answer 6

The five main layers of rock in Malta are Upper Coralline Limestone, Greensand, Blue Clay, Globigerina Limestone, and Lower Coralline Limestone.

Question 7

Which rock layer is the oldest in Malta?

Answer 7

The oldest rock layer in Malta is the Lower Coralline Limestone.

Question 8

What are the characteristics of Upper Coralline Limestone?

Answer 8

Upper Coralline Limestone is known for its hardness and is often used in construction due to its durability.

Question 9

Why are fossils found in Maltese rocks?

Answer 9

Fossils are found in Maltese rocks because these rocks were formed from sediments that included the remains of sea creatures, which were compressed over millions of years.

Question 10

How is Blue Clay different from Globigerina Limestone?

Answer 10

Blue Clay is a softer, more easily eroded rock compared to the harder and more durable
Globigerina Limestone.

Question 11

How is porosity in rocks classified in the diagram?

Answer 11

Porosity in rocks is classified into three types in the diagram: non-porous (impermeable), porous (permeable), and porous connected (permeable).

Question 12

What is the difference between non-porous and porous rocks?

Answer 12

Non-porous rocks do not allow water to pass through them, while porous rocks have spaces that can hold water and allow it to pass through.

Question 13

Why are fossils commonly found in sedimentary rocks?

Answer 13

Fossils are commonly found in sedimentary rocks because these rocks are formed from sediments that include the remains of plants and animals, which are compressed over time.

Question 14

How does the porosity of a rock affect its permeability?

Answer 14

The porosity of a rock affects its permeability by determining how easily water can flow through the rock. Higher porosity usually means higher permeability, allowing more water to pass through.

Question 15

What is chalk and how is it formed?

Answer 15

Chalk is a soft, white limestone formed from the skeletal remains of sea creatures.

Question 16

What are the properties of clay when it is wet and when it is fired?

Answer 16

Clay is plastic-like when wet, meaning it can be easily shaped. When fired, it becomes hard and durable.

Question 17

What makes itacolumite unique among rocks?

Answer 17

Itacolumite is unique because it can bend due to its composition, making it useful as an oil reservoir and for ornamental purposes.

Question 18

How is chalk used in construction?

Answer 18

Chalk is used in construction because it is easy to cut and shape.

Question 19

Why is clay considered plastic-like when wet?

Answer 19

Clay is considered plastic-like when wet because it can be molded and shaped easily due to its fine particles and water content.

Question 20

How is limestone formed?

Answer 20

Limestone is formed over millions of years from the accumulation of shells, bones, and other calcium-rich materials on the ocean floor.

Question 21

What are the main uses of limestone in construction and architecture?

Answer 21

Limestone is used in construction and architecture due to its durability and ease of cutting. It is commonly used for building facades, flooring, and decorative elements.

Question 22

Why is limestone considered durable and workable?

Answer 22

Limestone is considered durable and workable because it is a hard rock that can be easily cut and shaped, making it suitable for various construction purposes.

Question 23

What materials contribute to the formation of limestone?

Answer 23

The formation of limestone involves materials such as shells, bones, and other calcium-rich remains of marine organisms.

Question 24

How does the presence of fossils in limestone indicate its origin?

Answer 24

The presence of fossils in limestone indicates that it originated from the accumulation of biological materials on the ocean floor, which were then compressed and solidified over time.

Question 25

What is quarrying?

Answer 25

Quarrying involves removing massive rocks from the land's surface, particularly for the construction industry.

Question 26

What are the two types of stone quarries identified in Malta and Gozo?

Answer 26

The two types of stone quarries identified in Malta and Gozo are hard stone quarries (such as coralline limestone) and soft stone quarries (such as globigerina limestone).

Question 27

Why are quarry sites important for Malta's construction industry?

Answer 27

Quarry sites are important because they provide raw materials for building and construction industries and offer employment opportunities.

Question 28

What are some advantages and disadvantages of quarrying?

Answer 28

Advantages of quarrying include providing raw materials at cheaper rates and supporting economic growth. Disadvantages include environmental issues such as habitat loss, pollution, and changes to landscapes.

Question 29

How does quarrying impact the environment?

Answer 29

Quarrying impacts the environment by causing habitat destruction, pollution, changes in water levels, and landscape scarring.

Question 30

What are some visual impacts of quarries on the Maltese landscape?

Answer 30

Quarries can be an eyesore, causing visual intrusion in the landscape.

Question 31

How does dust pollution from quarries affect people living nearby?

Answer 31

Dust pollution from quarries can cause respiratory problems for people living nearby and create dust issues for houses close to quarries.

Question 32

What type of pollution is caused by trucks carrying stones from quarries?

Answer 32

Trucks carrying stones from quarries can cause noise pollution.

Question 33

How can quarrying activities contaminate groundwater?

Answer 33

Quarrying activities can contaminate groundwater by introducing pollutants into the water supply.

Question 34

What are some environmental consequences of creating space for quarries?

Answer 34

Creating space for quarries can lead to the destruction of agricultural land and habitats for various species, such as birds.

Question 35

What are some environmental consequences of creating space for quarries?

Answer 35

Creating space for quarries can lead to the destruction of agricultural land and habitats for various species, such as birds.

Question 36

What are some sustainable ways to reuse disused quarries?

Answer 36

Disused quarries can be sustainably reused by converting them into parks, wildlife habitats, or lakes.

Question 37

How can disused quarries be rehabilitated?

Answer 37

Disused quarries can be rehabilitated by filling them with construction waste, converting them into agricultural land, theme or heritage parks, parking spaces, or solar farms.

Question 38

What is the difference between weathering and erosion?

Answer 38

Weathering is the breaking down of rocks, minerals, or other materials, while erosion is the movement of sediment from one place to another.

Question 39

What are the three types of weathering mentioned?

Answer 39

The three types of weathering mentioned are chemical weathering, biological weathering, and mechanical/physical weathering.

Question 40

Why is it important to restore disused quarries?

Answer 40

Restoring disused quarries is important to mitigate environmental impacts, provide new habitats, and make the land usable for other purposes.

Question 41

What is biological weathering?

Answer 41

Biological weathering is the process by which living organisms contribute to the breakdown of rocks and minerals.

Question 42

How do lichen and mosses contribute to the weathering of rocks?

Answer 42

Lichen and mosses contribute to the weathering of rocks by releasing acids that dissolve the rock they grow on, leading to chemical weathering.

Question 43

What role do burrowing animals play in biological weathering?

Answer 43

Burrowing animals contribute to biological weathering by digging into the ground, which breaks up rocks and soil, allowing for further weathering processes.

Question 44

How do tree roots cause biological weathering?

Answer 44

Tree roots cause biological weathering by growing into cracks in rocks. As the roots grow larger, they force the cracks to widen, eventually breaking the rock apart.

Question 45

What is the process of chemical weathering as described in the context of lichen and mosses?

Answer 45

The process of chemical weathering involves the release of acids by lichen and mosses, which dissolve the rock they grow on, leading to its disintegration and chemical alteration.

Question 46

What is frost shattering (freeze and thaw) weathering?

Answer 46

Frost shattering (freeze and thaw) weathering occurs when water collects in rock cracks, freezes and expands, causing the rock to break apart.

Question 47

How does onion skin (exfoliation) weathering occur?

Answer 47

Onion skin (exfoliation) weathering occurs when rocks are exposed to alternating heat and cold, causing the outer layers to expand and contract, eventually flaking off.

Question 48

What role do tree roots play in biological weathering?

Answer 48

Tree roots contribute to biological weathering by growing into cracks in rocks, expanding and breaking the rock apart as they grow.

Question 49

In what type of environment is frost shattering most likely to occur?

Answer 49

Frost shattering is most likely to occur in cold environments, such as mountainous regions.

Question 50

What happens to rocks during the day and night in onion skin weathering?

Answer 50

During the day, the warmth of the sun heats up the rock, causing the outer layers to expand. At night, cooler temperatures cause the rock to contract, leading to small pieces flaking off over time.

Question 51

What is biogeochemical weathering?

Answer 51

Biogeochemical weathering is a process where biological, geological, and chemical factors cause rocks to break down over time.

Question 52

How does chemical weathering affect rocks?

Answer 52

Chemical weathering affects rocks by breaking down the bonds that hold them together through chemical reactions, often involving water and gases.

Question 53

What is biogeochemical weathering?

Answer 53

Biogeochemical weathering is a process where biological, geological, and chemical factors cause rocks to break down over time.

Question 54

How does chemical weathering affect rocks?

Answer 54

Chemical weathering affects rocks by breaking down the bonds that hold them together through chemical reactions, often involving water and gases.

Question 55

What natural formations can result from the dissolution of limestone?

Answer 55

Natural formations such as caves can result from the dissolution of limestone.

Question 56

What role do tree roots play in biogeochemical weathering?

Answer 56

Tree roots contribute to biogeochemical weathering by growing into cracks in rocks, breaking them apart as the roots expand.

Question 57

How do caves form through chemical weathering?

Answer 57

Caves form through chemical weathering when rainwater, which has absorbed carbon dioxide and turned into a weak acid, dissolves limestone along joints, bedding planes, and fractures, eventually enlarging them enough to form caves.

Question 58

How are caves formed in the Maltese Islands?

Answer 58

Caves in the Maltese Islands are formed by the dissolution of limestone. Rainwater picks up carbon dioxide from the air, turning into a weak acid that dissolves the limestone along joints, bedding planes, and fractures, eventually forming caves.

Question 59

What is a doline and how does it form?

Answer 59

doline is a depression formed by local chemical weathering of soluble rocks, such as limestone. Water accumulates around a fissure or joint in the rock, dissolving it and creating a hollow that gradually enlarges.

Question 60

What are garigue landscapes and how do they develop?

Answer 60

Garigue landscapes are areas where limestone has become scarred and potholed through the action of acid rain. These potholes collect enough soil to support a thriving population of shrubs and other herbaceous plants, forming a unique vegetational community.

Question 61

What role does rainwater play in the formation of caves?

Answer 61

Rainwater plays a crucial role in the formation of caves by picking up carbon dioxide from the air and soil, turning into a weak acid that dissolves limestone, creating and enlarging cavities.

Question 62

How does acid rain affect limestone in karst landscapes?

Answer 62

Acid rain affects limestone in karst landscapes by reacting with its constituent chemicals, causing the rock to become scarred and potholed over time. This process contributes to the formation of unique geological features and supports diverse plant life.