Unit: Rocks Flashcards
What do Geologists look at?
mineral composition, color and texture of the rock
What does color give scientist?
provides clues to the rock’s mineral composition
What are 2 examples of color info?
granite- light colored rock having high silica
basalt-dark colored rock that is low in silica
What is a rock’s texture
look and feel of the rocks surface which is made up of the minerals or other fine rocks( grains)
What are the 3 grains?
grain size, shape, and pattern
What 3 groups to scientist classify rocks in?
sedimentary, igneous, metamorphic
How are igneous rocks formed?
created by magma or lava when it cools or crystalizes( obsidian)
How does sedimentary rocks form?
forms when rocks are broken down and joins together has rocks, plants, animals all pressed together
How is metamorphic rock formed?
forms when existing rock is changed by heat and pressure or chemical reactions
What are the 5 properties of minerals?
1.solid under normal conditions
2.naturally occurring
3.crystalline structure
4. definite chemical composition
5.inorganic substances
characteristic- color
used to identify a few minerals that have their own mineral color
characteristic- streak
color of the minerals powder
characteristic- luster
how light reflects off surface
characteristic-density
how dense it is
Characteristic hardness
how easily minerals break on surfaces