Bibliography

http://www.mcmc.org.au/
http://en.wikipedia.org/wiki/Sedimentary_rock
http://en.wikipedia.org/wiki/Scoria
http://home.vicnet.net.au/~foopnp/opnp.htm
http://www.parkweb.vic.gov.au/1park_display.cfm?park=167
http://en.wikipedia.org/wiki/Dights_Falls
http://www.melbourneplaygrounds.com.au/melbourneplaygrounds-info.php?id=21388
http://www.onlymelbourne.com.au/melbourne_details.php?id=3084

Yarra Bend Park: Part Six

What type of rock was used to construct the mill and millrace? Where did this rock come from?

The rock used to construct the mill and the millrace was a sedimentary rock type called bluestone blocks, that were taken from the Dight's old mill building.

Yarra Bend Park: Part Five

What is a mill? When was this mill constructed? Why was it constructed here? Why has this mill been preserved when most mills have not?

A mill is an operation to break down solid pieces and is often associated with breaking down wheat products. The mill was constructed in the early 1840's so a weir that was built on a natural rock bar so it could supply water to the mill. It was preserved because it was a water-turbine powered mill and the largest and most sophisticated mills built at the time in Victoria.

Yarra Bend Park: Part Four

How long might it take to make a sedimentary layer? How long might it take to make the rock face you see opposite?

Why aren't these rocks still at the bottom of the sea?

What geological features are visible?

The length of how long it takes for a sedimentary layer to be made varies. It may happen rapidly if evaporation of salt flats create chemical sedimentary rocks or slowly, if it's gradually depositing sediments by tidal waters which can take millions of years.
It would take millions of years to make the rock face seen opposite because of tidal waters, weathering and erosion.

The rocks aren't at the bottom of the sea any more because it got all washed up and tossed up onto shore.

The geographical features that are visible are the layers of rock and the folding.

Yarra Bend Park: Part Three

Dight's Falls

 A photograph and a description of Dight's Falls. Are there any other falls on the Yarra?

Dight's Falls are sandstones and interbedded mudstones that crop out as cliffs and bluffs along the left side of the bank of Yarra River. The cliffs today were former river bluffs that came up again as Yarra River was turned to the south by lava flows pouring down Merri Creek and Darebin Creek valleys.

They are naturally occuring rock falls that is located below the junction of Yarra River and Merri Creek. Dight's Falls has sandstone on the east and volcanic deposits on the north and west. It was first seen by Europeans and its name refers to John Dight and his brother Charles. 

It was used as a trading route and it was significant to Aboriginal clans. The completion of the Eastern Freeway in 1972 destroyed the Deep Rock Basin and transformed the area into a place to attract tourists. 
There are no other falls on the Yarra.

Yarra Bend Park: Part Two

 How has the natural environment of Merri Creek been impacted by the construction of the freeway?
 The natural environment of Merri Creek has been naturally slowly deteriorating due to weathering and it is recognised as a potentially hazardous site as there are a number of loose blocks on the cliff face and the steep rock of the face. The construction of the freeway has made Merri Creek worse than ever.

Yarra Bend Park: Part One

A map of Yarra Bend Park

A map of the general areas of Yarra Bend Park. Explain why Deep Rock is a significant place.

The Deep Rock is a significant place because it relates to Aboriginal history and when the Europeans arrived, they recognised the beauty of the park and they wanted to preserve it and keep it as a natural landmark.

Organ Pipes National Park: Part 6

A photograph of a scoria rock

A photograph of scoria, a description of the rock and a description of how it was formed.

Scoria is a less technical term for macrovesicular volcanic rock and it is commonly basaltic or andestic in composition. Scoria is considered light but has a gravity more than one and sinks in water. Scoria differs in the textural tone than other volcanic rocks because they have larger vesicles and thicker vesicle walls and is often darker in colour (dark brown, black or red).

Scoria is a rock full of bubble holes and the bubble holes were formed as the lava spewed out of the volcano and were trapped as the lava cooled and hardened.

Organ Pipes National Park: Part 5

Horizontal stones at Tessellated Pavement

Vertical stones at Tessellated Pavement

Include your photos. Explain how the tessellated pavement formed. Include a photo of the vertical columns as well of the rocks that make up the pavement.

The Tessellated Pavement was formed very much the same way as the Organ Pipes was formed except that it was built on "top" rather than underneath the lava flow and everyting from the Organ Pipes. This was not shown yet as the rocks in the Tessellated Pavement is much newer than the rocks that make up the Organ Pipes.

Organ Pipes National Park: Part 3

Sedimentary rocks underlying the New Volcanics in Organ Pipes National Park

 What are these rocks doing here? Why are sedimentary rocks so close to igenous rocks? Which rocks are older?

The valley of Jacksons Creek exposes steeply dipping fossilised Silurian sedimentary rocks overlain by flows from the Newer Volcanics basalt. They differ from the rocks in the Organ Pipes because these rocks are igenous rocks formed from lava while the latter are sedimentary rocks. The sedimentary rocks are so close to the igenous rocks because they were initially one type of rock but erosion, weathering and other natural disasters caused the rock to seperate and forming sedimentary rock. The igenous rocks are much older than the sedimentary rocks because they were the original rock that were there in the first place because they were created from the old volcanic areas in the park.

Organ Pipes National Park: Part 2

Organ Pipes close up

A photograph, and a written description of the Organ Pipes, an explanation of how they were formed, and an explanation about why they are considered so special a National Park had to be created.

 

The Organ Pipes are a set of basalt columns that are as straight and regular as regular pipes and it is the central feature of the park. They were formed a million years ago when a large lava flow which was about 70 metres thick spread over the plains from nearby volcano hills. A surface crust was formed and the lava beneath slowly cooled down and began to join together.  Vertical cracks on the surface began to develop and as the lava continued to get harder, the cracks got longer in length until the basaltic mass was divided into columns. Over the next million years, Jacksons Creek cut a deep valley through the basalt layer to expose the formation known as the "organ pipes".

They were considered so special that a National Park had to be created because environmentalists wanted to preserve the remaining flora, fauna and the unusual basalt formations along Jacksons Creek because the area was beginning to be settled in.

Organ Pipes National Park: Part 1

The rise and the end of Jackson's Creek.

Location of Organ Pipes National Park

Valley at the Organ Pipes National Park

 A map of the area, showing Jackons Creek - where it rises, where it ends, and the location of the Organ Pipes.

A photograph, and a written description of the valley, and an explanation of how the valley was formed.

The valley is a vast dry wasteland and an important part of the Organ Pipes National Park. The Maribyrnong Valley Committee decided to focus on the valley in 1972 and restore it to what it was before the Europeans came. The biggest problem was the serious rate of soil erosion. The MVC checked local valleys for vegetation, collected seeds, bred seedlings in their backyard, conducted fifteen working bees annually and started planting trees on the fact that large plants with root systems to match would stop the erosion. A member of the MVC did a bird survey for fifteen years, checking that the return of indigenous species would come back as the flora recovered.