Mr. Sierra’s ROCK CYCLE Prezi Notes
There are many different ways people
illustrate or describe the Rock Cycle
(just like with the Scientific Method).
Here is one example Æ
It is an ongoing process – without a
real beginning or end, and it can go in
any direction from one rock type to
any other.
There are 3 main Rock Types:
Igneous
Sedimentary
Metamorphic
You may notice that Magma and Sediment are included as transitional phases.
IGNEOUS Rock
Process:
Erosion & Sedimentation
SEDIMENTARY Rock
●
●
●
●
Forms when molten lava (magma) cools and become solid
The word "igneous" comes from Latin - meaning “fire”
(think of "igniting" something)
Crystals form as lava cools... the SLOWER it cools, the
LARGER the crystals! The cooling rate (how fast or slow)
determines the texture of igneous rock.
Wind and Rain cause rock to break down into sand, soil and
minerals. Erosion carries small particles of sediment until it
gets "deposited".
● Root word “sediment” = small particles (like sand)
● Goes through compacting & cementing (like glue)
● Usually has layers (horizontal lines) from “deposition”
● Fossils are only found in Sedimentary Rock
● The oldest layers are found at the bottom!
Process:
Heat & Pressure
As layers of rock and sediment pile up, the weight puts great
pressure on rocks down below. That plus, heat from magma
under the crust causes rock to "morph" into more dense rock.
METAMORPHIC Rock
Metamorphic: to “morph” = changing
● Formed from other rocks under heat and pressure
● Often has folded/wrinkled lines = “foliated”
Process:
Melting
Under enough heat and pressure, rock will eventually melt back
into Magma and begin the rock cycle over again.
…and that takes us back to the beginning again Æ see IGNEOUS Rock