Rocks - what a crack up!
Sandstone weathering and erosion
Science, Geography, History
Learning intentions
We are learning to identify the features of sandstone and to understand how weathering and erosion breaks it down.
We are learning how Aboriginal peoples used sandstone.
Teacher information
In this topic, students learn that Sydney is built upon ancient sandstone rock, which is subject to weathering and erosion. Weathering and erosion help shape many beautiful sandstone landmarks in Sydney and Australia. Students will have a chance to make their own model to investigate erosion by water, and will also learn how local Aboriginal peoples made use of sandstone in their lives.
Non-digital Lesson: Not online? Download the lesson here.
Stage: S2 KLA: Science, Geography, History
Welcome to sandstone country!
Come and join Claire inside a cave to explore sandstone and learn about the lessons for this activity.
Task 1: Let's rock!
Go outside and see if you can find some rocks. On a page in your work book or nature journal make some observations of your rock. You might like to do more than one rock.
Draw your rock
Write what the colour/s are of your rock
Is your rock crumbly?
Can you see little grains of sand?
Rub two rocks together, and see if you can get some rock dust. Rub this on the page, or mix with water to make paint
Do you think it’s a sandstone rock? Why?
Task 2: What is weathering and erosion?
Watch this video and learn how the Earth's surface is shaped by weathering and erosion. You can test your knowledge with a quiz which is at the end of the video, click the 'Test yourself' tab on the video link.
weathering-and-erosion.mp4Task 3: Let's build a model!
Erosion can cause huge changes in landscapes. If you look around your local environment, can you see evidence of erosion?
Watch this video and make your own model of water erosion. You can get creative, and use what you have available, it doesn’t have to be exactly the same as what you see in the video. Maybe use some sticks, leaves and twigs to help create your landscape.
Make Your Own Erosion! - #sciencegoals.mp4Task 4: Aboriginal use of sandstone
How do Aboriginal Peoples use sandstone?
Aboriginal Rock Engravings
Engravings into sandstone are made by sketching an outline, then a series of holes are drilled or 'pecked' along the lines with a pointed stone or shell. The holes are then joined by rubbing a sharp object along the line. Aboriginal rock engravings are not just art, but tell stories of Country, and sometimes tell the creation stories for a particular area. Most of the Aboriginal rock engravings in Ku-ring-gai Chase National Park show images of people or animals.
Sandstone shelters
Sandstone caves and overhangs are used by Aboriginal Peoples for many reasons. It may be for shelter to protect themselves from the weather, for example in heavy rain. Sandstone shelters were also used as a place where Aboriginal people ate. Shell middens are important cultural sites where the remains of shellfish gathered and eaten by Aboriginal people for thousands of years can be found. Sandstone caves across the Sydney area were also used for rock art such as hand stencilling.
Grinding grooves
Grinding grooves provide information about how stone tools were made. Aboriginal peoples made the grooves in the sandstone when they shaped and sharpened stone tools by grinding them against the rock.
Want to see more local Aboriginal sites in Bobbin Head Kur-ring-gai Chase National Park? Check out one of our other lessons in nature here!
Extension: What caused that?
There are many beautiful places in Australia shaped by weathering and erosion.
Now you have learnt all about weathering and erosion, complete the Weathering and Erosion in the Australian Landscape worksheet to identify the different types of weathering and erosion.
Want to know more?
Sydney, a city of sandstone
Sandstone is a sedimentary rock, made when sand grains stick together. Sandstone is deposited by rivers, the sea, or by the wind, and can sometimes appear in layers of different colours.
Sydney is a city built upon sandstone. Underlying Sydney is sandstone that is millions of years old. You can see natural sandstone on our beach cliffs, along the rivers and chances are under your feet when you go for a bushwalk.
You may have also noticed sandstone in buildings around Sydney. The sandstone for these buildings has been dug out of the ground and used in construction. For example, the Queen Victoria building, Sydney Town Hall, or simply some paths that you might walk on in a bushwalk.
More activities for your nature journals!
Download the Nature Journal prompts below. Print a copy and stick it into your nature journal.
My Nature Journal .pdf