Image attribution. Own work.
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The footpath surface is laid with Victorian Bluestone pavers. Bluestone is the common name used for basalt in Victoria. The pavers are quarried at the Lara Quarry just outside of Melbourne.
Melbourne has its distinctive architecture due to the use of bluestone in its buildings. Basalt in Melbourne was quarried in the Clifton Hill area (now exhausted). It is used in public buildings such as Melbourne Gaol, St Patrick's Catheral, and Victoria Barracks, to name a few.
Volcanic origins
The word basalt is probably derived from the an incorrect spelling of the Latin word basanites meaning "very hard stone", which came from the Greek word basanos meaning "touchstone". Basalt arises from solidified lava (lava being molten rock) after it has been extruded onto the Earth's surface. In that process, gas can be trapped within the molten rock. Usually, these gases escape. When they don't, they form what are called vesicles. In layperson terms, a vesicle is a cavity in a volcanic rock formed by the expansion of a bubble of gas that was trapped inside the lava. Vesicles are of interest to scientists as the trapped gases can given indications of the types of gases that were around when the rock was formed.
An active basalt lava flow in the United States. Image copyright. United States Geological Survey. Public Domain.
The pavers at the listed co-ordinates will give you an opportunity to look at lots of examples of basalt,
Questions
1. Find the tile "Boxes". Above the letter E in Boxes, look at the basalt tile that is there. What characteristics of that tile allow you to conclude that there are vesicles within the basalt?
2. The number of vesicles in a rock will give you an indication of how gaseous it was at the time of its formulation. Based on your observations, would you conclude that it was very gaseous, or not very gaseous?
Answers
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Feel free to post pictures of the location, but please don't post a picture of the pavers.
Sources.
http://www.darlingharbour.com/learn-explore/history-and-heritage/