mining in Australia
what is an ore?
A rock that contains enough of a valuable mineral to make mining worthwhile.
how are sedimentary rocks formed?
From layers of sediments being compacted and cemented over time.
how are igneous rocks formed
From cooled and solidified magma or lava.
how do metamorphic rocks form?
From existing rocks changed by heat and pressure.
What is the rock cycle?
A continuous process that changes rocks from one type to another.
name 1 mining method
Open-cut mining, underground mining, dredging, leaching
give an example of a sedimentary rock
Sandstone, limestone, shale, conglomerate.
name the 2 types of igneous rocks
intrusive and extrusive
name 1 metamorphic rock
Marble , slate
Which processes form sedimentary rocks?
Weathering, erosion, deposition, compaction, cementation.
name 2 minerals or ores that are mined in Australia
iron ore, gold, bauxite, lithium, nickel, diamonds.
What is a fossil and why are fossils usually found in sedimentary rocks?
Fossils are preserved remains of plants/animals; they form in soft sediments that harden into rock.
difference between intrusive and extrusive igneous rocks
Intrusive cool slowly underground (large crystals), extrusive cool quickly on the surface (small crystals).
metamorphic rocks take a long time to form true or false
true
Which rock type can turn into metamorphic rock?
Any rock type — sedimentary, igneous, or another metamorphic rock.
name 1 way mining benefits Australia's ecomony
Exports bring in money, create jobs, support local communitie
What process moves sediments from one place to another
Erosion (by wind, water, ice).
give an example of igneous rock
basalt, granite, obsidian, pumice, gabbro, diorite, and peridotite
Why are metamorphic rocks often hard and dense?
Heat and pressure cause minerals to recrystallise, making them more compact
what process turns rocks into magma
melting
name 1 environmental impact of mining and how it can be reduced
Habitat destruction → rehabilitate land after mining / reduce waste.
sedimentary locations are identified as places where sedimentary rocks are likely to form. name a sedimentary location
lakes, rivers, oceans,
Explain how crystal size tells you how fast the rock cooled.
Large crystals = slow cooling, small crystals = fast cooling
Explain the difference between foliated and non-foliated metamorphic rocks.
Foliated = layers/bands (slate, gneiss), non-foliated = no layers (marble).
Explain how an igneous rock could eventually become a sedimentary rock.
Igneous rock weathers into sediments → sediments erode, deposit, compact, cement into sedimentary rock