G11 - EARTH SCIENCE - LESSON 2

petrology

study of rocks

ways that rocks are classified

origin

mineral composition

texture

color

rocks

most common material of our planet

rocks

a hard mass of material came from the collection of common aggregate of grains of one or more minerals

mud and sand

materials that disaggregate are not classified as rock

rocks

vary in terms of size, color, texture, and hardness

rocks cycle

process wherein rocks evolve or change from one type to another

weathering

changes that rocks undergo

weathering

process that break down the rock because of exposure to the atmosphere

rock classification

sedimentary rocks

metamorphic rocks

igneous rocks

igneous rocks

formed from hot moltrn material called magma that has undergone solidification, cooled and hardneed due to high temperature

igneous rocks

with holess

igneous rocks

large and small crystal grains

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igneous textures

aphanitic

igneous textures

phaneritic

igneous textures

porphyritic

igneous textures

glassy

aphanitic

fine grained texture

aphanitic

form at the surface or as small masses within the upper crust where cooling is relatively rapid

phaneritic

coarse-grained

phaneritic

formed when large masses of magma solidify slowly below the surface

porphyritic

rocks which has large crystals embedded in a matrix of smaller crystals

Porphyritic

large crystals

groundmass

smaller crystals

glassy

during a volcanic eruption, molten rock is ejected into the atmosphere where it is quenched quickly. Rapid cooling may generate rocks with a ______ texture

sedimentary rocks

form when loose sediments or rock fragments hardened, cemented, and packed together

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classic sediments

chemical sediments

organic sediments

categories of sedimentary rocks

clastic rocks

formed mostly by weathering and erosion such as gravel, sand, silt, shale, and mud

chemical rocks

formed from hardened minerals usually dissolved in water, minerals can be separated from water by evaporation or precipitation

organic rocks

formed from remains of living organisms

metamorphic rocks

formed from previous igneous rocks or sedimentary rocks changes due to high pressure and temperature

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foliated

minerals are flattened, drawn out, and arranged in bands and parallel layers such as rocks that contain mica or iron magnesium minerals

unfoliated

fracture without definite pattern

contact metamorphism and regional metamosphism

types of metamosphism

contact metamorphism

an igneous or sedimentary rock is converted to metamorphic if it is direct contact with the source of heat

regional metamosphism

increase pressure and temperature is due to some processes known as plate tectonic and causes the formation of mountains

metamosphism agents

heat, pressure and stress, chemical activities / chemically active fluids

heat

provides the energy to drive chemical reactions that result in recystallization

pressure and stress

buried rocks are subjected to the force or stress, pressure as metamorphic agent exerted by the load above

chemical activities / chemically active fluids

the common fluid is water containing ions in solution

mineralogy

study of minerals

minerals

inorganic, solid, possesses orderly internal structure, has definite chemical composition, and occurs naturally

ores

minerals taken from the ground or mines. Minerals such as iron and copper come from this

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Minerals

all ________ are solid

Minerals

_________ form naturally; they are found in nature

Minerals

the substances that makeup _-------- are inorganic, and they are never part of living thing, nor are they formed by living things

Minerals

each kind of ______ has definite chemical composition or a limited range of compositions

Minerals

the atoms of _ are connected to one another in an orderly, repetitive arrangement

siliceous minerals

most abundant of the minerals

non-metallic minerals

contains carbonates, sulfates, and other compounds or native elements of sulfur

metallic minerals

include common metal ores. these ores have been formed due to a large process of chemical and physical changes

gem minerals

include precious and semi-precious stones

gem minerals

known for their color, luster, hardness, and crystalline form

crystal form

external expression of the orderly internal arrangement of atoms of a mineral

crystal form

can be based in the six systems of crystals which are: cubic, hexagonal, orthorhombic, monoclinic, and triclinic

luster

appearance or quality of light reflected from the surface of a mineral

color

most obvious property of a mineral and often unreliable diagnostic property

streak

color of a mineral in its powder

streak

obtained by rubbing the mineral across a piece of unglazed porcelain

cleavage

the tendency of a mineral to break along planes of weak bonding

cleavage

comes from latin word “to cut” or “to cleave”

fracture

tendency for minerals that do not exhibit cleavage when broken like quarts are said to be ________

specific gravity

number which represents the ratio of the weight of the mineral to the weight of an equal volume to water

hardness

measure of the resistance of a mineral to abrasion or scratching