Metamorphic Rocks

1
Metamorphic Rocks
2
Metamorphic Rocks

• LO To know how metamorphic rocks are formed

What does the term metamorphic mean? Break it
down What does morph mean? How can we link
this to a rock type?
3
Can you metamorphose chocolate?!

• Collect an instruction sheet and a mini mars bar.
• Work your way through the sheet filling out the
  different sections as you go.
• Stick the sheet into your book.

4
So what are metamorphic rocks?

• Metamorphic rocks are formed from existing
  sedimentary rocks that are changed because of
  heat or pressure
• Earth movements may cause rocks to be deeply
  buried or squeezed - these rocks are heated and
  put under great pressure but they do not melt (if
  they melt they become igneous rocks)
• The minerals they contain are changed chemically,
  forming metamorphic rocks

5
Formation

• Compare the following metamorphic rocks from the
  sedimentary rock they formed from (we know what
  sedimentary rock they formed from as they have
  the same chemical composition)

Heat PRESSURE
Limestone (with bivalve fossils)
Marble
6
(No Transcript)
7
Metamorphic Rocks

• Marble is formed from limestone
• Very high temperatures break down the shells and
  they form small crystals (but the rock does not
  melt)

Limestone
Marble
8
Metamorphic Rocks

• Slate is formed from clay
• As the clay gets heated and compressed the tiny
  plate-like particles align in the same direction
  (split into sheets, great for roofing material)

HEAT PRESSURE
Clay
Slate
9
How are diamonds formed?

• Read the diamonds are forever information and
  answer the questions.

10
Metamorphic

• Complete the metamorphic rocks worksheet

11
Metamorphic
12
What type of rock am I?

1. I am formed when lava cools quickly
2. I am formed from compaction of tiny grains of
   sand
3. I am formed deep within the earths crust from
   heat and pressure
4. I am formed from molten rock
5. I sometimes contain fossils
6. I am the hardest substance known to man
7. I am formed when magma cools slowly
8. I am easily eroded by acid rain