E.M Practical Task

PRACTICAL TASK:

ROCKS

Igneous Rocks:

They are formed underground or above ground when magma

 (if it is underground) or lava (when is above ground) cools.

Example:

Obsidian:         

# Formed when lava cools above ground.

        # Actually glass and not a mixture of minerals.
# It’s edges are sharp.

                     

Metamorphic Rocks:

Were igneous or sedimentary rocks before, that with the pressure,

wich fosters hit build up, and this causes them to change.

Example:

Schist Rocks: 
# Were igneous rocks before.
# Are formed from basalt.

                                # Transform into metamorphic because of 
 heat and pressure.

Sedimentary Rocks:

Are formed million years ago, by little pieces of earth or rocks

 that were erosion or weathering, this pieces get together

and formed the sedimentary rocks.

Example:

Conglomerate Rocks.
# Made up of large sediments.

              # It cemented together with dissolved
minerals.

                # Sediments are so large that pressure

       can’t hold the rock.

  

What rocks are similar to the ones we saw in class?

The ones that are very similar to the ones we saw in class are the Obsidian

and Schist Rocks. But the Conglomerate Rock is not similar to any rock 

that we saw in class.

PRECIOUS ROCKS	SEMIPRECIOUS ROCKS
It’s less common to find them, that’ why they are more value.	It’s more common to find them, that’s why they are less value.

By: Ganora, Florencia

                   &

       Villar C. Camila