Ausgeology. Senior secondary lessons

SACE Stage 2 Earth and Environmental Science · Topic 2: Earth’s resources

Coal, oil and gas.

Coal, oil and gas formed from living things: plants in swamps, and plankton and algae in seas and lakes. Burial and heat over millions of years turned their remains into fuels that people now use far faster than they form. This lesson follows how each one forms and collects, how geologists find it, how it is got out, and what that does to the land, water and air.

Slide sideways to see the whole picture.

Illustration
One imaginary basin holding the coal, oil and gas in this lesson and the ways each is got out. In real life they are in different places and formed at different times. Not to scale: the depths are squeezed and the seams, traps and wells drawn far bigger than they are.
  • 1A swamp forest lays down peat (screen 2)
  • 2Brown coal near the surface (screen 2)
  • 3Black coal, deeper and older (screen 2)
  • 4A source rock makes oil and gas (screen 3)
  • 5An arch traps them under shale (screen 4)
  • AOpen cut (screen 7)
  • BUnderground longwall (screen 7)
  • CCoal seam gas wells (screens 5 and 7)
  • DA well into a trap on land (screen 7)
  • EA platform at sea (screen 7)
  • FShale gas: a well along the rock, cracked open (screens 5 and 7)

Australia’s coal, oil and gas in numbers

Coal mines

In 2024 Australia had 96 operating black coal mines and 3 operating brown coal mines. Queensland produces 57% of the black coal and New South Wales 42%.

Geoscience Australia: Australia’s Energy Commodity Resources 2026, Coal

Coal seam gas

Australia produced 1,665 petajoules of coal seam gas in 2024, nearly all of it from the Bowen and Surat basins in Queensland. A petajoule (PJ) is a million billion joules.

Geoscience Australia: Australia’s Energy Commodity Resources 2026, Gas

Oil

In 2023–24 Australia produced 738.5 PJ of crude oil, condensate and LPG, and over 94% of it was exported.

Geoscience Australia: Australia’s Energy Commodity Resources 2026, Oil

Where they come from

Twelve places

What we are learning

How coal, oil and gas form and where they collect, how geologists find them, how they are extracted, what their extraction and use do to the environment, and how long Australia’s reserves might last.

I can

  • 1explain how coal forms, and identify its ranks from hand specimens.
  • 2describe how oil and gas form in a source rock.
  • 3describe the structures that trap oil and gas.
  • 4describe how coal seam gas and shale gas are formed, held and got out.
  • 5explain how seismic and gravity surveys are used to find oil and gas.
  • 6explain how the depth, extent and location of a resource decide how it is extracted.
  • 7describe environmental impacts of extracting and using coal, oil and gas.
  • 8use data to judge how long Australia’s fossil fuel reserves might last.

SACE Stage 2 Earth and Environmental Science, Topic 2: Earth’s resources. This lesson covers the topic’s energy resources: coal, oil, gas and unconventional gas. Metallic and non-metallic mineral resources are in the ore deposits lesson.

How this lesson works: concept attainment

  1. Study labelled examples. Some are Yes examples of an idea; some are No. They appear one at a time.
  2. Write a rule that sorts them, and change it whenever a new example does not fit.
  3. Test your rule on new examples that are not labelled.
  4. Name the idea and compare its definition with your rule.

Three ideas are taught this way: coal (screen 2), the petroleum trap (screen 4) and unconventional gas (screen 5). Screen 3 follows how oil and gas form. Screens 6 to 9 follow how they are found and extracted, what that does to the environment, and how long the reserves will last. Screen 10 has eight questions.

Working with a partner works well: argue about each new example before you change your rule. Your answers and notes are saved in this browser, so you can stop and come back.

My notebook

Printable activity

Draw the traps

Two pages: draw and label four petroleum traps, show where gas, oil and water collect in each, and explain how they got there. It goes with screen 4.

Activity sheet (PDF) Editable (Word)

1Concept 1 of 3

Coal.

What makes a rock coal, and how does a swamp become a coal seam?

Coal forms where plant material piles up faster than it can rot and is then covered by sediment. Start by working out what makes a rock coal from the examples below. Then follow a swamp as it becomes a coal seam.

Geologists rank coal by how far burial has changed it. As Geoscience Australia puts it, with more time, heat and pressure, plant material first forms peat, then brown coal, then sub-bituminous coal, bituminous coal and, last of all, anthracite. Water, carbon dioxide and methane are given off and escape, so the coal becomes richer in carbon. In Australia, sub-bituminous coal, bituminous coal and anthracite are together called black coal, and brown coal is also called lignite.

Rank by rank

Two measures
Show the numbers as a table

Brown coal holds little energy per tonne mostly because so much of it is water. Victoria’s brown coal is 48 to 70% water as it is mined. Resources Victoria gives its energy as 8.6 MJ/kg on average as it is mined, but 26.6 MJ/kg measured on dry coal. One gigajoule per tonne (GJ/t) is the same as one megajoule per kilogram (MJ/kg).

Australia’s black coal is 299 to 145 million years old, and most of it formed in the Permian period. Its brown coal is younger, mostly 66 to 23 million years old. Brown coal is mined only in Victoria, where the seams in the Latrobe Valley are up to 100 m thick.

Key idea

Coal forms where plant remains pile up in swamps faster than they rot, and are buried. Over millions of years, heat and pressure drive off water and gases, so the rank rises from peat to brown coal, black coal and anthracite, and the share of carbon rises with it.

As peat becomes brown coal, then black coal, then anthracite, what happens to it?

My notebook

PHow petroleum forms

Oil and gas.

How do plankton and algae become oil and gas, and where do they go?

Crude oil and natural gas, together called petroleum, come from algae, plankton and other organic material that settled on the floor of a sea or lake and was buried in mud. What happens next depends on how deep the mud is buried and how hot it gets.

Oil and gas are made in one rock and usually end up in another. Geologists give rocks three jobs:

  • A source rock is rich in organic matter, often a dark shale, and makes oil and gas when it is heated.
  • A reservoir rock, such as many sandstones and limestones, has spaces that can hold oil and gas (its porosity), connected so that they can flow through it (its permeability).
  • A seal is a rock that oil and gas cannot pass through, such as shale, clay or salt.

Which job does each rock do?

0 of 6 sorted

Oil and gas are less dense than the water in the rocks, so once they leave the source rock they rise, through porous rock and along faults and fractures, until a rock they cannot pass through stops them. Where nothing stops them, they reach the surface as a seep. On the Yampi Shelf, off the Kimberley coast of Western Australia, a Geoscience Australia survey saw plumes rising from the sea floor and gas bubbles with oily films at the sea surface, and its samples suggested that sea life clusters around the active seeps.

Key idea

Oil and gas form when organic-rich mud is buried and heated over millions of years: oil at about 60 to 120 °C, gas at about 100 to 200 °C. Less dense than water, they then rise through porous rock until a seal stops them or they escape at the surface.

Why must a source rock be buried deeply before it makes oil?

My notebook

2Concept 2 of 3

Traps.

What stops oil and gas rising all the way to the surface?

Oil and gas keep rising until something stops them. Where the rocks are arranged so that they cannot rise any further, they collect, and that is where explorers look for them. Work out what every trap has from the examples below.

Traps come in two families. Structural traps form when rock layers are deformed into a shape that stops oil and gas moving any further: an arch, called an anticline, is the most common, and a fault or a rising body of salt can do the same. Stratigraphic traps form where the reservoir rock itself changes into another kind of rock or is cut off.

Four common traps

Not to scale
  • Sandstone (porous)
  • Shale (seals)
  • Source rock
  • Salt
  • Gas
  • Oil

Cross-sections, not to scale, with the layers steepened so the shapes are easy to see. In each trap, gas sits above oil and oil above water, because gas is the least dense of the three and water the most.

Key idea

A petroleum trap needs a reservoir rock, a seal over it, and a shape that closes off the top, so that oil and gas collect at a high point. Folds, faults and rising salt make structural traps; a reservoir rock that changes or is cut off makes a stratigraphic trap.

Sandstone is folded into an arch, but the rock over the top of the arch is sandstone too. What happens to oil rising into it?

My notebook

Printable activity

Draw the traps

Draw and label an anticline, a fault trap, a salt dome trap and a stratigraphic trap, show where gas, oil and water collect, and explain how they got there.

Activity sheet (PDF) Editable (Word)

3Concept 3 of 3

Unconventional gas.

How can gas be held in a rock that it cannot flow out of?

Not all gas has moved into a trap. Some is still held where it formed. Geoscience Australia counts this kind of gas as unconventional: coal seam gas, shale gas and tight gas. Work out what makes gas unconventional from the examples below.

Coal seam gas is held on the surfaces of the coal, inside a seam. The seam is generally full of water, and the pressure of that water keeps the gas as a thin film on the coal. Some of the gas formed as the coal was buried deeply and heated, and some was made by microbes breaking down the organic matter at lower temperatures.

Shale gas is held in the shale it formed in, in pores and cracks that are not connected. To get it out, a well is drilled down into the shale and then sideways along it, and the rock is cracked open.

The Beetaloo Sub-basin, Northern Territory

The Beetaloo Sub-basin lies under the Sturt Plateau, between Mataranka and Elliott, about 500 km south-east of Darwin. Geoscience Australia estimated its shale gas resources at 8,015 PJ at the end of 2024.

While a scientific inquiry, chaired by Justice Rachel Pepper, studied the risks of hydraulic fracturing, the Northern Territory had a moratorium on it. The inquiry’s final report, delivered in March 2018, had chapters on water, land, greenhouse gas emissions, public health, Aboriginal people and their culture, and social and economic impacts, and made 135 recommendations. On 17 April 2018 the Government lifted the moratorium. The first gas from a pilot project began flowing into the Territory’s pipelines on 1 September 2026.

Key idea

Unconventional gas is spread through a large area of rock that holds on to it: on coal, held there by water pressure, or in tight rock such as shale. It has not collected in a trap, so it needs special methods to get it out: pumping water out of coal seams, or horizontal wells and hydraulic fracturing.

Why is water pumped out of a coal seam before its gas will flow?

My notebook

6From discovery to the future · 1 of 4

Find it.

How do geologists see a trap that is kilometres underground?

Only a well shows for certain what is in a trap, and wells are expensive. So explorers first build a picture of the rocks below the surface, mostly with two kinds of survey: gravity surveys and seismic surveys.

A gravity survey measures tiny differences in the pull of gravity. Gravity is a little stronger over dense rock and a little weaker over less dense rock. The sedimentary rocks that fill a basin almost always have low densities, so basins show up as gravity lows. Over the top of an anticline, where denser rock is arched up, gravity is a little stronger; over a salt dome, it is a little weaker.

A seismic survey sends sound into the ground and records the echoes. Each boundary between different layers of rock reflects some of the sound back. On land, the sound can come from trucks with vibrating plates, and the echoes are recorded by sensitive microphones on the surface called geophones. At sea, a ship tows airguns and long cables of hydrophones, called streamers. The time an echo takes to go down to a layer and back up, the two-way time, is turned into a depth using the speed of sound in the rocks.

A 2D survey uses one line of sound and receivers to make a single cross-section, like the one you made. A 3D survey tows several streamers at once to build a detailed three-dimensional picture of a whole area.

Key idea

Gravity surveys show where the density of the rocks changes, picking out basins, arched-up rock and salt. Seismic surveys time the echoes from boundaries between layers to map their shapes, and so find structures that could be traps. Only drilling shows whether a trap is full.

An echo from the top of a sandstone arrives 1.2 seconds after the shot. What does the 1.2 seconds measure?

My notebook

7From discovery to the future · 2 of 4

Get it out.

Why is each fuel extracted in a different way?

How a resource is got out of the ground depends on how deep it is, how far it extends and where it is: close to the surface or far below it, under land or under the sea, in rock it can flow through or rock it cannot. Match each Australian deposit to the way it is extracted.

How is it got out?

0 of 7 matched

Two meanings of shale oil. Oil made by heating oil shale in a retort, as at Gladstone, is often called shale oil. Geoscience Australia also uses the name for oil held in shale and other tight rock, which is got out the same way as shale gas: with horizontal wells and hydraulic fracturing.

Gas for export. To ship gas overseas, it is cooled until it turns into a liquid, liquefied natural gas (LNG). Gas from the North West Shelf, from the fields piped to Darwin, and from coal seams piped to Curtis Island near Gladstone is made into LNG and shipped overseas.

Key idea

The method follows the deposit. Coal close to the surface is dug from open cuts and deeper coal is mined underground. Oil and gas in traps flow up wells, on land or from platforms at sea. Unconventional gas needs its rock opened up: water pumped out of coal seams, or shale cracked open along horizontal wells. Oil shale is mined and heated.

Which deposit is most likely to be mined from an open cut?

My notebook

8From discovery to the future · 3 of 4

The footprint.

How do extracting and using coal, oil and gas affect the land, water, air and living things?

Every step, from the mine or well to the power station or engine, can change the environment around it. Four Australian cases show how the non-living parts of ecosystems, such as air, water and rock, are linked to the living parts, including people.

Latrobe Valley, Victoria, 2014

The Hazelwood mine fire

On 9 February 2014, embers, most likely from bushfires outside the mine, set fire to exposed brown coal in the Hazelwood open cut. It burned for 45 days. Smoke and ash overwhelmed the nearby town of Morwell: fine particles were well above the advisory standard, carbon monoxide was high, and vulnerable people in part of the town were advised to move away for a time. The Board of Inquiry found that the mine’s owner was not adequately prepared, and that fire is an ever-present risk in a brown coal mine.

Hazelwood Mine Fire Inquiry Report, 2014

Timor Sea, 2009

The Montara oil spill

From 21 August to 3 November 2009, oil and gas flowed unchecked into the Timor Sea from a well in the Montara oil field, about 250 km off the north-west coast. The operator estimated that 400 barrels (64 tonnes) of crude oil were lost each day. The Commission of Inquiry found that the main barrier in the well, its cemented casing shoe, had failed, that the operator had not followed sensible oilfield practices, and that the regulator’s regime was totally inadequate.

Report of the Montara Commission of Inquiry, 2010; Australian Maritime Safety Authority

Surat Basin, Queensland

Water from coal seam gas

Coal seam gas wells in the Surat area pump out around 52,000 megalitres of water a year. The water is generally brackish, with a salinity of about 300 to 10,000 mg/L, against about 35,000 mg/L for seawater. Taking it out lowers the water pressure in the coal seams and in the layers of rock around them.

Office of Groundwater Impact Assessment, Surat UWIR 2025 (consultation draft); Independent Expert Scientific Committee (2014)

New South Wales and Queensland

Subsidence over longwall mines

Longwall mining removes all the coal from each long panel, and the roof and the rock above collapse into the space left behind. The ground above a deep longwall mine typically sinks 1 to 2 m, and it can sink 2 to 3 m above a thick seam mined at shallow depth.

Independent Expert Scientific Committee: Subsidence from longwall coal mining (2014)

From gas well to farm bore

Put the chain in order

Using the fuels. Burning coal gives off sulfur dioxide, which irritates the nose, throat and airways and can end up as sulfate in rain, part of acid deposition. In New South Wales, coal-fired power stations are the largest source of it. Greenhouse gases, including methane, also escape from coal mines and from oil and gas wells, plants and pipelines. These fugitive emissions were 47.2 million tonnes of carbon dioxide equivalent in 2023–24, about a tenth of Australia’s net emissions of 466.4 million tonnes. Over 100 years, a tonne of methane has 28 times the warming effect of a tonne of carbon dioxide, the value Australia’s greenhouse accounts use.

Coal, gas or uranium for electricity?

Greenhouse gases, whole life
Show the numbers as a table

Life-cycle values count every stage, from getting the fuel and building the power station to running it and dealing with its waste. The chart compares greenhouse gases only. Other impacts differ too: nuclear power leaves radioactive waste that has to be managed for a very long time, and burning coal gives off sulfur dioxide.

Key idea

Extracting and using fossil fuels links the non-living and living parts of ecosystems: a burning coal mine fouled a town’s air, a leaking well spilt oil into the sea, and pumping water from coal seams lowers the water in rock around them. Burning the fuels, and methane escaping from them, adds greenhouse gases to the atmosphere.

Why did the Hazelwood mine fire burn for so long?

My notebook

9From discovery to the future · 4 of 4

How long will it last?

Are Australia’s coal, oil and gas reserves sustainable?

Coal, oil and gas took millions of years to form, so they are not replaced on any human timescale. How long they last depends on how much is known, how fast it is produced, and how much more is found.

Years of reserves

Geoscience Australia, 2026

Geoscience Australia divides the reserves known at the end of 2024 by the production in 2024. The answer is the reserve life: how many years the reserves would last at that rate.

Show the numbers as a table

Work it out

Divide reserves by production
Geoscience Australia calls its reserve life figures “a snapshot in time that can only be used for general impressions”, because they assume that production stays at the 2024 rate and that the reserves used up are not replaced by new discoveries.Geoscience Australia, Australia’s Energy Commodity Resources 2026

Oil found and oil produced

The world, 2016
Show the numbers as a table

For the world’s conventional oil, the question is not only how much is left, but how fast new oil is found. A review by the UK Energy Research Centre found that most of the world’s conventional oil was discovered between 1946 and 1980, and that discoveries peaked in the 1960s. A widely cited graph suggests that more oil has been produced than discovered every year since 1980, although the reserves added each year, which include upward revisions to fields already found, have been larger than production over most of that time. This is the debate about peak oil. In Australia, Geoscience Australia says the limited conventional oil resources are being used up faster than new discoveries replace them.

Key idea

Coal, oil and gas are not readily replaced. At 2024 rates, Australia’s oil and gas reserves would last 8 to 17 years and its black coal about 165. Reserve life is a snapshot, though: discoveries, prices, technology and demand all change it.

Australia’s crude oil has a reserve life of 8 years. What does that tell you?

My notebook

10Show what you know

Show what you know.

Eight questions, one for each of the I can statements on screen 1. You get one try at each, so think before you tap.

Which hand specimen is the highest rank of coal?

Which set of conditions turns the remains of plankton and algae into oil?

Oil fills the thin end of a layer of sandstone that thins out to nothing inside shale. What kind of trap is this?

Which of these is unconventional gas?

How does a gravity survey help in exploring for oil and gas?

Oil and gas lie in a trap under the sea floor, 50 km offshore. How are they most likely to be extracted?

Which statement about the water pumped out of coal seams is supported by this lesson?

Reserve life in years: black coal 165, conventional gas 15, crude oil 8. Which conclusion is best supported?

Printable activity

Draw the traps

Draw and label four petroleum traps, show where gas, oil and water collect, and explain how they got there.

Activity sheet (PDF) Editable (Word)
For teachers

Curriculum

SACE Board of South Australia, Stage 2 Earth and Environmental Science Subject Outline (accredited for teaching at Stage 2 from 2018, reissued for 2025), Topic 2: Earth’s resources. NT students take the subject as part of the NTCET. The topic outline says:

Students investigate the formation of non-renewable mineral and energy resources; techniques used for their discovery; identification and extraction, and effects of the extraction; and use of these resources on ecosystems.

This lesson covers five of the topic’s seven Science Understanding statements, for energy resources. The first statement (how people use geological resources) and the formation of metallic resources are in the ore deposits lesson.

Non-renewable mineral and energy resources are formed in various ways over geological time-scales, so are not readily replenished.

  • Discuss the sustainability of reserves of fossil fuels, and metallic and non-metallic resources.

The formation of non-renewable energy resources, including fossil fuels and unconventional gas, is related to their geological setting.

  • Explain the processes by which coal is formed.
  • Describe the processes by which petroleum and coal-seam gas are formed and are trapped.
  • Describe structures within which petroleum may be trapped.

A variety of techniques can be used to discover deposits of mineral and energy resources and identify the extent and quality of these resources.

  • Discuss techniques for finding mineral resources, using magnetic and electromagnetic surveys, geochemical sampling, and drilling.
  • Explain how seismic and gravity surveys are used in petroleum exploration.
  • Discuss how the presence of a resource can affect the surrounding physical and chemical environment.

The depth, extent, and location of mineral and energy resources determine the method of extraction.

  • Describe the essential features of underground, open-cut, and in-situ leaching methods of extraction of mineral resources.
  • Explain how the size, shape, and depth of a mineral deposit influence the choice of extraction method.
  • Explain how petroleum, shale oil, coal, and coal-seam gas are extracted from the Earth in different locations.

The extraction and use of mineral and energy resources influences interactions between the abiotic and biotic components of ecosystems, including hydrologic systems.

  • Describe potential environmental impacts that can be associated with the extraction, use, and processing of mineral and energy resources.

Where the lesson covers them:

  • Non-renewable resources and the sustainability of fossil fuel reserves: screen 9 (Geoscience Australia’s reserve life for coal, gas, oil and uranium; oil discovered against oil produced; peak oil). Metallic and non-metallic reserves are in the ore deposits lesson.
  • The formation of non-renewable energy resources: screen 2 (how coal forms; ranks of coal, with hand specimens in 3D), screen 3 (how petroleum forms and migrates), screen 4 (the structures that trap petroleum) and screen 5 (how coal seam gas and shale gas form and are held).
  • Discovery techniques: screen 6 (gravity and seismic surveys in petroleum exploration). How a resource can affect its surroundings: seeps, screens 3 and 6. Magnetic and electromagnetic surveys, geochemical sampling and drilling for minerals are in the ore deposits lesson.
  • Extraction: screen 7 (petroleum on land and at sea, shale oil in both its senses, coal by open cut and longwall, coal seam gas and shale gas). Underground, open-cut and in-situ leaching for minerals are in the ore deposits lesson.
  • Environmental impacts: screen 8 (the Hazelwood mine fire, the Montara oil spill, coal seam gas water, longwall subsidence, sulfur dioxide, fugitive emissions, and the life-cycle emissions of electricity from coal, gas and uranium) and screen 5 (the Northern Territory inquiry).

Science as a human endeavour runs through the lesson. Its key concepts in the outline include these, used on the screens shown:

New technologies improve the efficiency of scientific procedures and data collection and analysis. This can reveal new evidence that may modify or replace models, theories, and processes.

Screen 6: seismic surveys, from single 2D lines to 3D surveys; screen 5: horizontal wells and hydraulic fracturing, the specialised technology unconventional gas needs.

The use of scientific knowledge may have beneficial or unexpected consequences; this requires monitoring, assessment, and evaluation of risk, and provides opportunities for innovation.

Screen 8: the Hazelwood and Montara inquiries, and the Office of Groundwater Impact Assessment’s monitoring of coal seam gas water in Queensland.

Science informs public debate and is in turn influenced by public debate; at times, there may be complex, unanticipated variables or insufficient data that may limit possible conclusions.

Screen 5: the Northern Territory’s scientific inquiry into hydraulic fracturing; screen 9: reserve life as a snapshot, and the debate about peak oil.

Assessment design criteria the tasks give practice for: KA1 and KA2 (the concept attainment rules, the checks and the extraction match), IAE2 and IAE3 (the seismic survey and the reserve life data), KA3 (the Beetaloo inquiry, the footprint cases and the supply screen) and KA4 (the Draw the traps sheet, which asks for the labelled diagrams of petroleum traps that the outline suggests).

How the lesson is taught

Screens 2, 4 and 5 use concept attainment (Bruner, Goodnow and Austin, 1956; Joyce, Weil and Calhoun, 2015). Students meet labelled Yes and No examples one at a time, write a rule and change it as each new example appears, test it on unlabelled examples, and only then see the concept’s name, definition and essential attributes. The No examples are chosen to break the likeliest wrong rules: peat and charcoal break the rule made of plants and burns, and oil shale breaks a rock that gives off fuel; a tilted layer, a faulted arch and an eroded arch break oil under rock; and conventional traps break gas deep underground. Each concept ends with students comparing their rule with the definition, which is where most of the learning happens.

  • Lesson 1: screen 1, then screen 2. Run the first concept with the whole class: show each new example, have pairs say their rule aloud, and ask for a rule that fits every example so far before you show the next one. Then the swamp-to-seam model and the ranks. With a school coal kit, use real peat, brown coal, black coal and anthracite alongside the 3D specimens.
  • Lesson 2: screens 3 and 4 in pairs, then start the Draw the traps sheet.
  • Lesson 3: screen 5, finishing with a class discussion of the benefits and risks of unconventional gas.
  • Lesson 4: screens 6 and 7.
  • Lesson 5: screens 8, 9 and 10.

Students working alone can do every screen in order.

Handle with care

  • Coal, oil and gas are many families’ work, in Queensland, New South Wales, the Latrobe Valley and the Northern Territory especially, and the future of fossil fuels is contested. The lesson sets out what the sources say without telling students what to think about the industry. Let students bring their own knowledge.
  • Hydraulic fracturing in the Beetaloo Sub-basin is a live issue in the Northern Territory, including for the Traditional Owners of the land concerned; the inquiry gave a chapter to Aboriginal people and their culture. The lesson does not speak for anyone. To go further, use the inquiry’s report, and invite local voices following your school’s protocols.
  • Some students are anxious about climate change. Screens 8 and 9 give figures without forecasts or blame. Give students room to talk, and look at what is being done as well as at the problem.
  • Safety: if you use real coal specimens, have students wash their hands afterwards, and do not burn coal in class.

Misconceptions the screens target

  • Coal and oil are made from dinosaurs (screens 2 and 3). Coal is made from plants; oil and gas from algae, plankton and other organic material.
  • Anything black that burns is coal (screen 2). Charcoal and peat are made of plants and burn, but have not been buried and changed into rock.
  • Oil lies in underground lakes or caves (screens 3 and 4). It fills the pore spaces of a reservoir rock such as sandstone.
  • Oil and gas are found where they formed (screen 3). Most move out of a source rock into a reservoir rock.
  • Coal seam gas lies under the water in a seam (screen 5). It is held on the coal by the water’s pressure.
  • A seismic survey finds oil (screen 6). It shows the shapes of the layers; only drilling shows what a trap holds.
  • Reserve life is a countdown (screen 9). It is a snapshot that assumes nothing changes.

About the data and the pictures

  • All the cross-sections, the two step-through models, the survey line and the well drawings are models, not surveys of real places, and each says what is stretched or simplified. The 3D specimens are drawn in code from descriptions, not photographed. The map’s markers are placed by latitude and longitude, approximately.
  • Coal: Geoscience Australia, Coal (Australian Energy Facts; formation, carbon by rank on a dry, ash-free basis, ages) and Black Coal (Australian Resource Reviews; the names black and brown coal); GA, Australia’s Energy Commodity Resources (AECR) 2026, Coal (mines and production by state); National Greenhouse Accounts Factors (July 2017), Table 1 (energy content factors); Resources Victoria, Coal (Latrobe Valley seams, cover, water and energy: the 8.6 MJ/kg is on a net wet basis and the 26.6 MJ/kg on a gross dry basis); SA Department for Energy and Mining (Leigh Creek). Sources differ on brown coal carbon: 60 to 70% (GA) against 65 to 70% (Resources Victoria).
  • Petroleum: Wyoming State Geological Survey (formation; conventional traps); AAPG Wiki (source rocks, migration, geothermal gradients of 24 to 41 °C/km); US Energy Information Administration (2016) for the oil window, 60 to 120 °C, and gas window, 100 to 200 °C. Sources give different windows: the Wyoming survey gives about 65 to 150 °C for oil. The model takes the surface as 20 °C and a rise of 30 °C per kilometre.
  • Traps and seals: Britannica, petroleum trap; AAPG Wiki; SEG Wiki. Seeps: Geoscience Australia Survey 267, Yampi Shelf.
  • Unconventional gas: Geoscience Australia, AECR glossary (conventional and unconventional resources; shale gas; tight gas; shale oil); Queensland Government, Coal seam gas; CSIRO GISERA (how coal seam gas formed); Australian Government, Beetaloo Strategic Basin Plan (hydraulic fracturing); Scientific Inquiry into Hydraulic Fracturing in the Northern Territory, Final Report (2018); NT Government (the moratorium lifted); NT Territory Coordinator and APA (first gas, 1 September 2026); GA AECR 2026, Gas (Beetaloo resources).
  • Surveys: Geoscience Australia, Gravity and Exploring for the Future (vibrator trucks); USGS Fact Sheet 239-95 (basins as gravity lows); Britannica, petroleum production (anticlines and salt domes); NOPSEMA, Marine seismic surveys (airguns, streamers, 2D and 3D); Geological Survey of Victoria (geophones); US EPA, Seismic reflection (two-way time). The survey model’s speeds of sound and densities are typical values chosen for the model.
  • Extraction: Resources Victoria (open cuts; Hazelwood closed in 2017, Yallourn to close in 2028, Loy Yang expected to run to 2035); IESC (2014), Subsidence from longwall coal mining; Victorian Government, NOPSEMA and Britannica (Bass Strait); SA Department for Energy and Mining (Cooper Basin); Office of Groundwater Impact Assessment, Surat Underground Water Impact Report 2025, consultation draft (wells and water; the approved report took effect on 1 May 2026, so check its figures); Queensland Parliament, Record of Proceedings, 10 November 2015 (first LNG cargo from Gladstone); Geoscience Australia, Oil Shale; Queensland Department of Environment and Heritage Protection (2013), review of the Gladstone oil shale plants; Britannica, petroleum production (natural flow and artificial lift).
  • Footprint: Hazelwood Mine Fire Inquiry Report (2014); Report of the Montara Commission of Inquiry (2010) and AMSA (the operator’s estimate of the loss); IESC (2014), Coal seam gas extraction and co-produced water; NSW EPA (2024) and EPA Victoria (sulfur dioxide); National Inventory Report 2024, Volume 1 (fugitive emissions; methane GWP of 28 from the IPCC Fifth Assessment Report); IPCC AR5 WGIII Annex III, Table A.III.2 (life-cycle emissions). The share of about a tenth is worked out from the inventory’s figures.
  • Supply: Geoscience Australia, AECR 2026, Table 1.1 (reserves at the end of 2024; production in 2024, with coal production for 2023–24). GA’s oil chapter gives crude oil reserve life as less than 8 years and its overview as 8 years. IEA, Global oil discoveries and new projects fell to historic lows in 2016 (news release, 2017; the yearly production is worked out from its 69 million barrels a day); Sorrell and others (2009), UK Energy Research Centre.
  • Map: Geoscience Australia, state governments, NOPSEMA, INPEX and the State Library of Western Australia. The outline is from Natural Earth.

Answers at a glance

  • What makes a rock coal: the Yes examples are A (black coal), C (brown coal) and E (anthracite). Tests: 1 No (petrified wood), 2 Yes (Leigh Creek coal), 3 No (obsidian), 4 Yes (Bowen Basin coal).
  • Rock jobs: dark shale rich in plankton remains, source; sandstone with connected spaces, reservoir; thick salt, seal; shale over sandstone, seal; porous reef limestone, reservoir; mud rich in algae laid down where the water held little oxygen, source.
  • Trap or no trap: the Yes examples are A (anticline), C (fault), E (pinch-out) and G (salt dome). Tests: 1 Yes (reef), 2 No (no seal over the dome), 3 Yes (unconformity), 4 No (sandstone against sandstone across the fault).
  • Conventional or unconventional: the Yes examples are A (coal seam gas), C (shale gas) and E (tight gas). Tests: 1 Yes (coal seam), 2 No (salt dome trap), 3 Yes (shale), 4 No (trap below an unconformity).
  • Survey: the echoes arrive earliest, and gravity is highest, in the middle of the line. A well at 8 to 12 km finds gas with oil below it; at 7 or 13 km, oil; elsewhere, water.
  • Extraction: Latrobe Valley, open cut; deep black coal, underground; Bass Strait and the Cooper Basin, wells that flow; Surat Basin, wells that pump out water; Beetaloo, horizontal wells and fracturing; oil shale, mine it and heat it.
  • Gas well to farm bore: wells pump out water; pressure in the seams falls; pressure falls in the layers next to them; bore water levels drop; make good.
  • Reserve life by hand: crude oil 1,255 ÷ 162 = 7.7 (GA: 8); coal seam gas 28,955 ÷ 1,665 = 17.4 (GA: 17); black coal 1,877,705 ÷ 11,398 = 164.7 (GA: 165).
  • Checks: q-coal, loses water and gases; q-oil, heated to about 60 to 120 °C; q-traps, keeps rising with no seal; q-ugas, the water’s pressure; q-find, down and back; q-extract, the thick, shallow seam; q-foot, exposed coal; q-last, at the 2024 rate if none were added.
  • Exit check: x1 hard, black and glassy (anthracite); x2 burial in low-oxygen mud, then 60 to 120 °C; x3 stratigraphic; x4 gas in the shale it formed in; x5 density changes over structures; x6 wells from a platform; x7 lowers pressure in nearby layers; x8 oil and gas run out much sooner than coal at 2024 rates.

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References

  • Borthwick, D. (2010). Report of the Montara Commission of Inquiry. Commonwealth of Australia.
  • Bruner, J. S., Goodnow, J. J., & Austin, G. A. (1956). A study of thinking. Wiley.
  • Joyce, B., Weil, M., & Calhoun, E. (2015). Models of teaching (9th ed.). Pearson.
  • Pepper, R., and others (2018). Final report of the Scientific Inquiry into Hydraulic Fracturing in the Northern Territory. Northern Territory Government.
  • Schlömer, S., and others (2014). Annex III: Technology-specific cost and performance parameters. In Climate change 2014: Mitigation of climate change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press.
  • Sorrell, S., and others (2009). Global oil depletion: An assessment of the evidence for a near-term peak in global oil production. UK Energy Research Centre.
  • Teague, B., Catford, J., & Petering, S. (2014). Hazelwood Mine Fire Inquiry Report. Victorian Government Printer.

Sources

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