A rock is a naturally occurring aggregates of minerals and/or mineraloids.

1. ROCKS
By Prof. Liwayway Memije-Cruz

2. ROCKS
• Rocksaremadeup of
two or moreminerals
• They areNOT crystal
• Rocksarecollections
or aggregatesof one
or moremineral.

3. Rocksareclassified into:
• IgneousRock
• Sedimentary Rock
• Metamorphic
Rock

4. IGNEOUSROCK
 It istherock formed by the
solidification of molten magma.
 Areformed from themolten liquid
mineralsthat liebelow theearth’s
crust.
 Most abundant typeof rock

5. Two categoriesof IgneousRock
Plutonic or Intrusive:
 Characterized by largecrystal sizes.
 They cool slowly deep in Earth’scrust.
 Ex. (granite, gabbro and diorite)

6. Volcanic or
Extrusive:
it comesfrom lava.
finegrained and quickly
cooled.
Ex.(basalt, obsidian and
pumice)

7. SEDIMENTARY ROCK
• Thesesedimentsare
moved by wind, water,
iceor gravity.
• Sedimentary rocks
represent 7% of the
Earth’scrust, but they
cover 70% of the
Earth’ssurface

8. METAMORPHIC ROCK
 Rocksthat havechanged due
to intensetemperatureand
pressure
 Meta” means“ change” and
morphosismeans“ form ” in
Greek
 Igneous, sedimentary and
other metamorphic rockscan
changeto become
metamorphic rocks.
 Gneiss, acommon typeof
metamorphic rock