Show Menu
Cheatography

EngGeology214 Cheat Sheet (DRAFT) by

Engineering Geology study notes for finals

This is a draft cheat sheet. It is a work in progress and is not finished yet.

MATTER and MINERALS

Definition of a mineral
-naturally occurring
-inorganic
-solid
-specific chemical composition
-ordered atomic structure
Polymorph: two different minerals that have the same compos­iti­onbut different crystal structures
E.g. graphite and diamond
What is a crystal?
-any natural solid with an ordered, repetitive atomic structure
-a single continuous piece of crysta­lline solid bounded by flat surfaces that grew naturally.
Crystal growth
-Solidi­fic­ation of melt: freezing of liquid; atoms attach to mineral surface; growth starts with a crystal seed.
-Precip­itation from a solution: minerals seperate from water; groundwater->geode.
Solid-­state diffusion: atoms or ions move through a solid(slow).
Biomin­era­lis­ation: living organisms cause minerals to precip­itate: clams
-Gas precip­itate: volcanic vents
Geode
a spherical hollow within a rock comprising of inward projecting crystals
 

MATTER and MINERALS

Crystal structure
-ordered chemical crysta­lline structure
-internal atomic arrang­ement determined by ionic size
-crystal lattice = 3D geometric pattern in which atoms are arrang­ed-> controls outter shape
Amorphous: A solid in which atoms are not arranged in definite crystal struct­ure­(glass)