Continue Your GeoAdventure!
Congratulations, Geo Explorer!
You solved mysteries, discovered ancient fossils and travelled through billions of years of Earth's history.
Want to learn even more? Here are the answers to your workbook, along with some amazing extra facts!
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Geological True or False Answers
1. All fossils are bones.
False
Bones can become fossils, but so can footprints, burrows, leaves, shells, eggs and even dinosaur poo! Fossils are any preserved evidence of ancient life.
Did you know?
Some ripple marks preserved in Western Australia are more than 3 billion years old!
2. The oldest rocks in the world are found in Western Australia.
False
Rocks are made from tiny crystals called minerals. The oldest known mineral ever discovered is a tiny zircon crystal found in the Jack Hills of Western Australia. It is about 4.4 billion years old and formed when the Earth was very young.
The oldest known complete rock is found in Canada, where the ancient Acasta Gneiss is about 4.0 billion years old. Scientists have also found even older rocks in Quebec that may be around 4.16 billion years old, but their exact age is still being studied.
3. Australia was once joined to Antarctica.
True
Australia and Antarctica were once connected as part of a giant supercontinent called Gondwana. Over millions of years, the continents slowly drifted apart to their present positions.
4. Tiny little creatures can change the atmosphere.
True
Ancient microbes began producing oxygen through a process called photosynthesis billions of years ago. Over time, this changed Earth's atmosphere, making it possible for more complex plants and animals to evolve.
5. Diamonds are made from squashed coal.
False
Diamonds and coal are both made mostly of the element carbon, but they form in completely different ways. Diamonds form deep underground under enormous heat and pressure, while coal forms from ancient plants buried in swamps.
Even though they are both made of carbon, the carbon atoms are arranged differently. This gives them very different properties. Diamonds are the hardest natural material on Earth, while coal is soft and can easily be broken.
6. Some fossils are older than dinosaurs.
True
Life existed for billions of years before dinosaurs appeared. Fossils of ancient microbes, trilobites and giant sea scorpions (called eurypterids) are all much older than dinosaurs.
7. Humans are very new to Earth.
True
Earth is about 4.6 billion years old, but modern humans have only been around for about 300,000 years. If Earth's history was one day long, humans would appear in the last few seconds before midnight!
8. The first life on Earth formed on land.
False
The earliest life began in the oceans billions of years before plants and animals moved onto land. These tiny microbes eventually changed Earth's atmosphere and made complex life possible.
Geo Detective Answers
1. Why do we find things usually found in water, such as ripples in sand and fish bones, high up in the rocks of hills and mountains?
Many rocks begin as layers of sand, mud or silt that settle on the bottom of oceans, lakes or rivers. As more and more sediment builds up, the layers become buried. Over millions of years, heat and pressure squeeze them together to form solid rock.
Things like ripple marks, footprints, shells and fish bones can become trapped in these layers. They may be preserved as fossils or as ancient structures in the rock.
Later, powerful forces inside the Earth can fold, tilt and push these rocks upwards to form hills and mountains. Over millions of years, wind, rain and rivers wear away the rock, revealing the ancient fossils and ripple marks for us to discover.
2. What causes the large gorges in places like Kalbarri or Karijini?
Water is one of the most powerful forces shaping our planet. Over millions of years, rivers slowly wear away solid rock. Every flood carries tiny grains of sand and gravel that act like sandpaper, gradually cutting deeper and deeper into the landscape.
Rain, floods and weathering continue to widen and shape the gorge, creating the spectacular cliffs and valleys we see today.
3. Why do some rocks have layers while others do not?
Some rocks form when layers of sand, mud or shells settle one on top of another in oceans, lakes or rivers. Over millions of years, these layers are buried and squeezed into solid rock, so the layers are still visible.
Other rocks, such as granite, form when molten rock cools and hardens deep underground. Because they didn't form in layers, they usually look solid and uniform instead.
4. Why do sand dunes move?
Although sand dunes may look like they stay in one place, they are constantly moving. Wind blows tiny grains of sand up one side of a dune and drops them on the other side. Over time, this causes the whole dune to slowly move across the landscape.
Some dunes move only a few centimetres each year, while others can travel several metres each year if the winds are strong enough.
Wordsearch Answers
