Fossil Fuels

• Fossil fuels — coal, petroleum, natural gas formed over millions of years from dead organisms.
• Limited and non-renewable resources.
• Formation of coal from forest remains; petroleum from marine micro-organisms.
• Need for conservation.

1. Fossil fuels — energy-rich deposits buried and transformed by heat/pressure over geological time.
2. Coal formation — swamp plants buried → peat → lignite → bituminous → anthracite (increasing carbon).
3. Petroleum formation — marine plankton buried in sediments → crude oil and natural gas in porous rocks.
4. Natural gas — mainly methane (CH₄); found with petroleum.
5. Non-renewable — consumption rate far exceeds formation rate.
6. Real world — India's coal belts; Mumbai High offshore oil; PNG pipelines.

Tracing origin of petrol at filling station

Step 1 — Crude oil extracted from underground/ocean wells.
Step 2 — Refinery separates fractions (petrol, diesel, kerosene).
Step 3 — Petrol transported to pump.
Step 4 — Millions of years ago: marine organisms → sediments → petroleum.

• Thinking fossil fuels renew quickly (millions of years to form).
• Misconception: coal is pure carbon from start (formed gradually).
• Confusing natural gas with LPG cylinder gas only (LPG is propane/butane mix).
• Believing petroleum only on land (offshore wells common).

• What are fossil fuels? Give three examples.
• How is coal formed in brief?
• Why are fossil fuels called non-renewable?

Open the Practice tab for graded questions on Fossil Fuels.