ROCK FORMATION Flashcards
Name the 3 main types of rocks that all rocks are grouped in
Igneous Rocks
Sedimentary Rocks
Metamorphic Rocks
Give an explanation of Igneous Rocks and name 5
This rock forms when magma (underground) and lava (above ground) cools down and solidifies. These rocks are grouped according to
- minerals in the rocks,
- time it takes to cool down
- and where the cooling took place
eg. Granite, Basalt, Pumice, Obsidian, Peat
Give an explanation of Granite
Granite forms in the crust.
Its Magma - rich in silica (silicon and oxygen), that cools down very slowly just below the surface, crystals r formed. Used in construction - strong & hard.
Explain Basalt
PS ba(SALT) refers to sea - remember
It’s lava that cools down quickly. Temp is 1100 - 1250, forms a hard dark rock. Can be found over large part of earth and ocean.
Commonly used for tar roads or hot stone massages
This rock retains heat for longer than others
Which rock is full of bubbles explain why?
PUMICE:
Volcanic eruption where temp and pressure reduce quickly and together. Used as beauty tool to soften hard dry skin on heals.
Which rock were used as cutting tools in olden days
Obsidian:
Volcanic glass. Forms quickly without crystals,
Is dark and sharp edges - used for cutting or spear heads
What is PEAT
PEAT:
Formed from volcanic ash, grey, yellow or brown.
Used for counter tops of floors
Which rock plays an important role in learning more about the history of our world?
Sedimentary Rocks
Sedimentary rocks form when sediment are deposited in layers over time. What does sediment include?
dust, mud, iron ore, rock salt, organic material
Where does this sediment settle and why
The process occurs in large water masses, where weather conditions can not interfere with the rock forming process.
Where do we find sedimentary rocks
On the surface of the earth, very little in the crust
Name the 5 sedimentary rocks and their uses
LIMESTONE:
Filler for paper, plastic, paint
Fine limestone in breakfast cereals and calcium tablets
SANDSTONE:
Very soft stone good for statues and used in buildings like walls, tiles, pillars
MUDSTONE:
Formed in water. Used in construction and decoration
COAL:
Used to produce electricity and to make steel and cement.
CALY STONE:
Popular for building and pottery
Clay stone is when what stone weather to dust?
Granite
The coal that we use today where is it derived from? Where does it come from?
From plants that lived millions of yrs ago in swamps
How did coal form?
The dead plants formed layers and was covered by layers of sediment and water on top of it for millions of yrs.
The pressure and high temp caused the plants to form rocks
