Rocks

It is a concept used to explain how the three basic rock types are related and how Earth processes, over geologic time, change a rock from one type into another.

An aggregate of minerals or rocks that are coherent.

WHAT IS THE IMPORTANCE OF STUDYING MINERALS?

Three TYPES OF ROCKS

Any crystalline or glassy rock that forms from cooling of a magma.

TYPES OF IGNEOUS ROCKS

Crystallized below the surface of the earth (P or V) - igneous

PHANERITIC texture: coarse-grained (P or V)

Examples: Granite, Diorite, Gabbro (P or V)

Examples of Plutonic Rocks

Crystallized on the surface of the earth

APHANITIC texture: fine-grained (P or V)

Examples: RHYOLITE, ANDESITE, BASALT

VOLCANIC ROCKS -examples

rocks that form near the surface of the earth through chemical precipitation from water or by cementation of loose fragments.

Breaking down of rocks to sediments (Classification of sedimentary rocks)

Compaction and cementation of sediments to rocks (Classification of sedimentary rocks)

–causes the disintegration of rock to smaller fragments (Classification of sedimentary rocks)

disintegration of rocks and minerals by a physical or mechanical process. Example: frost or ice wedging, burrowing of animals, roots of plants (Classification of weathering; sedimentary rocks)

chemical alteration or decomposition of rocks and minerals Examples: hydrolysis, hydration, oxidation (Classification of weathering)

TYPES OF SEDIMENTARY ROCKS

Classified on particle size • clastic or non-clastic?

The presence of variable grain sizes is indicative of sedimentary differentiation which is actually a function of processes happening in different sedimentary environment. -clastic or non-clastic?

Formed through evaporation and precipitation (Type of Sedimentary rocks)