A lot of cachers avoid earthcaches due to their perception that they are difficult, we have made the earth science lesson easy to help get more people interested.
The Shrine of Remembrance
Is dedicated to those from Victoria who served and died in World War One. The Shrine of Remembrance is Victoria’s principal war memorial and the focus for commemorative ceremonies and marches. It was built between July 1928 and November 1934 in remembrance of those 114 000 men and women of Victoria who served, and those who died, in the Great War of 1914-1918. The Duke of Gloucester dedicated Melbourne’s Shrine of Remembrance at the Domain before an audience of over 300,000 people.
The Tympana are sculptures at the northern and southern ends of the Shrine. The Northern Tympana is "The call to arms" and shows a winged goddess symbolic of Mother England calling her children to defend her. The Southern Tympana is "The Homecoming" showing Australia at peace. At each corner of the Shrine, buttresses support large statues sculpted by Paul Montford, titled Patriotism, Justice, Peace and Goodwill, Sacrifice
About 6000 tonnes of stone was quarried from Tynong’s Granite Hill for the construction of the shrine in the late 1920s. The granite was said to have been selected for its distinctive silvery colour and its exceptional hardness and the fact that it “split straight”, which was ideal for a long-lasting monument.
The Granite Hill quarry, which has long been out of operation, is now listed as a site of state significance but the granite belt extends north where another open-cut quarry has been established.
In some areas, granite is used for gravestones and memorials. Granite is a hard stone and requires skill to carve by hand. In the Western world until the early 18th century, granite could only be carved by hand tools with generally poor results
Three things distinguish granite.
First, granite is made of large mineral grains (The word "granite" comes from the Latin granum, a grain) that fit tightly together.
Second, granite always consists of the minerals quartz and feldspar, with or without a wide variety of other minerals (accessory minerals). The quartz and feldspar generally give granite a light color, ranging from pinkish to white. That light background color is punctuated by the darker accessory minerals. Thus classic granite has a "salt-and-pepper" look. The most common accessory minerals are the black mica biotite and the black amphibole hornblende.
Third, almost all granite is igneous (it solidified from a magma) and plutonic (it did so in a large, deeply buried body or pluton). The random arrangement of grains in granite—its lack of fabric—is evidence of its plutonic origin.
Amateur Granite, Real Granite and Commercial Granite
With only a little practice, you can easily tell this kind of rock in the field. A light-colored, coarse-grained rock with a random arrangement of minerals—that's what most of us mean by "granite." Ordinary people and even rockhounds agree.
That's OK, but that's amateur granite.
Geologists are professional students of rocks, and what you would call granite they call granitoid. True granite is only one of the granitoids, a granitoid with quartz content between 20 and 60 percent and a feldspar content in which alkali feldspar rather than plagioclase feldspar predominates.
Stone dealers have a third set of criteria for granite. Granite is a strong stone because its mineral grains have grown tightly together during a very slow cooling period. And the quartz and feldspar that compose it are harder than steel.
This makes granite desirable for buildings and for ornamental purposes such as gravestones. Granite takes a good polish and resists weathering and acid rain. But stone dealers use "granite" to refer to any rock with big grains and hard minerals. So many types of commercial granite seen in buildings and showrooms don't match the geologist's definition. Black gabbro or dark-green peridotite, or streaky gneiss, which even amateurs would never call "granite" in the field, still qualify as commercial granite in a countertop or building.
How Granite Forms
Granite is found in large plutons on the continents, in areas where the Earth's crust has been deeply eroded. This makes sense, because granite must solidify very slowly at deeply buried locations to make such large mineral grains.
Lavas erupt all over the Earth, but lava with the same composition as granite (rhyolite) only erupts on the continents. That means that granite must form by the melting of continental rocks. That happens for two reasons: adding heat and adding volatiles (water or carbon dioxide or both).
And the processes of plate tectonics, can cause basaltic magmas to rise underneath the continents. In addition to heat, these magmas release CO2 and water, which helps rocks of all kinds melt at lower temperatures. With the slow release of heat and fluids from that basalt, a large amount of continental crust could turn to granite at the same time.
To Log this EarthCache, please send an email with answers to the following questions to our Geocaching.com account.
Your caching name and the EarthCache name
Looking at the wall in front of you what are the 3 prominent colour of stone making up the Granite ?
What reaction is occurring on some of the stones which is causing a change of colour?
Why do you think only some blocks are showing the change of colour?
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