Lecture 6 Minerals and Rocks 4

Question 1

where do sedimentary rocks form

Answer 1

on or near Earths surface

Question 2

what is erosion

Answer 2

geological process in which materials are worn away and (potentially) transported naturally by wind or water

Question 3

what is weathering and what factors allow it to happen

Answer 3

breaking down or dissolving of rocks and minerals on Earths surface

driven by factors such as:
- water
- ice/snow
- acids
- salts
- plants
- animals
- animals
- temperature fluctuations

Question 4

what are examples of sedimentary rock found on Mount Royal

Answer 4

• Limestone
• Shale

Question 5

what do erosion and weathering do

Answer 5

they slowly break down mountains, boulders, and larger rocks into smaller rocks and sediment/unconsolidated materials

Question 6

what are examples of unconsolidated materials

Answer 6

• gravel
• sand
• silt
• clay

Question 7

what is dissolution and another word for it

Answer 7

Dissolution = chemical weathering
- a form of weathering wherein slightly acidic water (pH less than 7) slowly wears down rock
- process by which soluble rocks/minerals are dissolved/incorporated into water due to the passage of water over the rock surface, entry of water into rock fractures or entry into rock pores

Question 8

what does frost do to rocks

Answer 8

frost causes rocks to fracture
- when rain absorbed by limestone surface freezes, it exerts pressure on the rock below, fracturing it

Question 9

what does it mean for a substance to be soluble

Answer 9

when it can dissolve/become incorporated into a liquid such as water

Question 10

is dissolution slower or faster in more or less soluble rocks/minerals

Answer 10

• dissolution is faster in MORE soluble rocks/minerals
• dissolution is slower in LESS soluble rocks/minerals

Question 11

what does limestone consist of + what is it

Answer 11

calcite (mineral made up of calcium carbonate CaCO3)
- limestone is a rock
- soluble

Question 12

what does dolostone consist of + what is it

Answer 12

dolomite [mineral made up of calcium magnesium carbonate, CaMg(CO3)2]
- dolostone is a rock
- soluble

Question 13

what does gypsum consist of + what is it

Answer 13

calcium sulfate, CaSO4 or CaSO4.2H2O
- gypsum is rock or mineral
- soluble

Question 14

what does halite consist of + what is it

Answer 14

sodium chloride (NaCl)
- halite is a mineral
- soluble

Question 15

which is more soluble
- limestone
- gypsum
- dolostone

Answer 15

gypsum is more soluble than both

Question 16

why does halite only exist in a certain environment + what is that environment

Answer 16

halite is very solvable and therefore only exists in dry environments

Question 17

what does combined erosion, weathering and dissolution do

Answer 17

it creates raw materials for making new sedimentary rocks

Question 18

what are raw materials

Answer 18

smaller rocks and sediment/unconsolidatd materials
- gravel
- sand
- silt
- clay

Question 19

what are raw materials, new minerals and new rocks generated by

Answer 19

lithification

Question 20

what is lithification (meaning and processes)

Answer 20

• from ancient Greek word “Lithos” meaning “rock”
• the making of rocks
• divided into two distinct processes:
  1. Compaction
  2. Cementation

Question 21

What is compaction

Answer 21

here are the three different definition/explanations on the slides:
- as more sediments accumulate above, clasts are forces closer together
- compaction is a process that squeezes or compacts sediments
- process by which sediment/unconsolidated materials and remains of plants/animals (ex. moss, mollusk shells) become compacted/packed down by weight of sediment/unconsolidated materials piled on above them

Question 22

What is compaction

Answer 22

here are the three different definition/explanations on the slides:
- as more sediments accumulate above, clasts are forces closer together
- compaction is a process that squeezes or compacts sediments
- process by which sediment/unconsolidated materials and remains of plants/animals (ex. moss, mollusk shells) become compacted/packed down by weight of sediment/unconsolidated materials piled on above them

Question 23

what is cementation

Answer 23

three definitions:
- groundwater moves between the grains and leave behind mineral deposits, bonding the grains to each other
- “glue” takes place when dissolved minerals are deposited in the tiny spaces among sediments

1. water moving through grains/clasts in compacted materials leaves behind mineral crystals
2. mineral crystals stick/cement/bond compacted materials together
3. compacting/compressing eventually results in release of any water and compacted layers of sediment becomes rock

Question 24

what are clastic rocks

Answer 24

(e.g., conglomerate)
- rocks composed of broken pieces of other rocks bonded together

Question 25

what is a clast

Answer 25

a fragment within clastic rocks

Question 26

what is precipitation

Answer 26

process by which water rich in molecules that make up minerals/rocks gradually evaporates, allowing molecules to deposit and form mineral crystal/rocks

Question 27

what happens in Death Valley (California) and what does it leave behind

Answer 27

mineral crystals form out of shallow after that flooded Death Valley, the driest location in North America leaves behind the following minerals: - halite (NaCl) - calcite (CaCO3) - gypsum (CaSO4 or CaSO4.2H2O) - borax (Na2B4O5(OH)4.8H2O)

Question 28

what are the two categories that sedimentary rocks can be classified as

Answer 28

- detrital sedimentary rock - chemical sedimentary rock

Question 29

what are detrital sedimentary rocks

Answer 29

- consist of organic and/or inorganic materials - formed from eroded/weathered rock fragments, smaller rocks, sediments/unconsolidated materials, organic materials - all aforementioned “ingredients are referred to as detritus, hence the name detrital sedimentary rock

Question 30

what is detritus latin for

Answer 30

worn down

Question 31

examples of detrital sedimentary rock

Answer 31

- conglomerate - breccia - sandstone - siltstone - shale (ie., mudstone)

Question 32

what does organic detrital sedimentary rock consist of

Answer 32

consists of animal/plant parts (organic material) that decay in ground

Question 33

what does organic detrital sedimentary rock undergo and how long does it take

Answer 33

over thousands or millions of years, organic material undergoes compaction and cementation (lithification), forming rock

Question 34

what’s special about peat

Answer 34

it doesn’t undergo complete lithification its a sedimentary material largely consisting of partially decayed vegetation/organic materials such as peat moss - formation of peat is the first step in forming another important and controversial organic sedimentary rock

Question 35

what are uses of peat

Answer 35

- peat harvesting in Scotland - used for energy - gardening - farming

Question 36

what does peat become

Answer 36

coal

Question 37

what is coal

Answer 37

a sedimentary rock made up of plant matter compressed over millions of years

Question 38

how does coal form

Answer 38

over years, with increased layers of sediment above the peat, increasing depth of burial and increased temperatures, peat is converted to lignite (one of four coal types)

Question 39

what are the four coal types and how do they come about

Answer 39

increased time and higher temperatures can convert lignite into 3 other coal types - lignite - then subbituminous coal - then bituminous coal - and ultimately anthracite

Question 40

where do we see coal

Answer 40

given its carbon content: - coal is burned to generate electricity used to manufacture steel - coal train in canada - coal mine in BC

Question 41

what is the carbon content in each type of coal

Answer 41

- lignite (25-35% carbon) - subbituminous coal (35-45% carbon) - bituminous coal (45-86% carbon) - anthracite (86-97% carbon)

Question 42

what is steel made of

Answer 42

- mix of iron (Fe) and carbon (C) - steel can contain up to approximately 2% carbon

Question 43

why is coal important to the canadian economy

Answer 43

in 2021, canada produced 47.6 million tons (1 ton = 1000 kilograms) of coal, of which 61% was sued to manufacture steel, and 39% used to generate electricity

Question 44

mining and burning of coal harmful to environment and organisms because…

Answer 44

** need to add

Question 45

how much of canadas electricity in 2020 came from burning coal

Answer 45

6% - by 2030, canada wants to phase out electricity generated using coal

Question 46

what is the percentage of electricity from coal in alberta, saskatchewan, and nova scotia

Answer 46

alberta: 44% saskatchewan: 43% nova scotia: 10%

Question 47

coal production percentage in canada

Answer 47

63% BC 21% alberta 17% saskatchewan

Question 48

in 2021, canada was the 7th largest exporter of coal in the world with how many tons + where does canada export coal to

Answer 48

32 million tons exported - china - south korea - japan - india

Question 49

what percentage of global electricity comes from coal in 2022

Answer 49

36% (followed by natural gas with 22% (3% comes from other fossil fuels fossile fuels still produce over 60% of the worlds electricity)