1	"Rocks are the most common..." Rocks are the most common material on Earth. They are naturally occurring aggregates of one or more minerals. Rock divisions occur in three major families based on how they formed: igneous, sedimentary, and metamorphic. Each group contains a collection of rock types that differ from each other on the basis of the size, shape, and arrangement of mineral grains. The rock cycle is an illustration that is used to explain how the three rock types are related to each other and how Earth processes change a rock from one type to another through geologic time. Plate tectonic movement is responsible for the recycling of rock materials and is the driving force of the rock cycle
2	ROCKS
3	The Rock Cycle A Model What are rocks: A mixture of minerals, mineraloids, glass, or organic matter Some rock forming minerals include feldspar, quartz, hornblende and mica Granite is a mixture of feldspar, quartz, mica, hornblende, and other minerals How are they mixed? Do they stay the same forever? Rock Cycle Cycle shows 3 types of rock and the processes that form them Throughout earth’s history, rocks of each type have been changed into other types by natural forces Melting Cooling and hardening Weathering and erosion Compacting and cementing Heat and pressure
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5	Sediments Sediments are particles that come from all rock types Carried by wind and water over thousands of miles Worn away rock is not destroyed rock Elements forming rocks and minerals not destroyed Only changes form Law of Conservation of Matter Changes in Rock Cycle don’t create or destroy Weathering processes break away existing rocks, even mountains Mineral matter broken away by wind, water, or ice but remains same Physical change Some mineral particles dissolve in streams and reacts with other particles to form new minerals Chemical change New minerals may be different from original rocks and minerals
6	How Do Earth Processes Affect Rocks?
7	"Igneous Rocks" Igneous Rocks Formed from cooling magma (molten rocks and minerals) or lava(magma that reaches earth’s surface) Quickly cooling lava forms extrusive or volcanic and have small mineral grains Slowly cooling magma forms intrusive or plutonic and have large mineral grains Sedimentary Rocks Sediment-pieces of rocks, minerals, organic remains and dissolved minerals from water When sediment becomes solid it is sedimentary rock Sediment piles up on land, riverbeds, ocean floor and the layers build up over time. Clastic, chemical, or organic sedimentary rocks form in different ways