Earth Science Midterm 1

Maturity (sedimentary rocks)

Combination of composition, sorting, and roundness

Neutrons

No charge/Neutral (in nucleus)

Mass Number

Number of protons + neutrons in atom (can differ in same element)

Atomic Number

Number of protons in atom

Theory

Principle formed to support data patterns

Sorting (clastic sediment)

Process where bigger sediments are deposited earlier in a river so that the end of the river is all tiny sediment grains

Rounding (clastic sediment)

Process where sharp corners are broken off of grains

Protons

positive charge (in nucleus)

Streak

Color of the mineral when powdered/smeared on streak plate

Pegmatitic igneous texture

Very slow cooling produces extremely coarse grained huge crystals

Pahoehoe

Very smooth/ropey lava that looks like flowing toothpaste

Flood basalts

extremely huge amounts of low viscosity mafic lava

Mohs Scale

1-10 scale to measure mineral hardness

Decompression melting

A decrease in pressure lowers a rocks melting temperature

Bowens reaction series

A diagram that shows how different minerals cool and crystalize at different temperatures

Sill (Volcano feature)

A horizontal intrusion of magma that flows between rock layers

Xenolith (Volcano feature)

A piece of foreign rock that gets incorporated into the magma chamber

Dike (Volcano feature)

A vertical intrusion of magma that cuts across existing rock layers

Metallic Bond

All of the atoms in a substance can share many electrons.

Hypothesis

Assumption made before testing has been done

Ionic Bond

Attraction between positively and negatively charges ions(atoms)

Luster

Describes the way a mineral reflects light (metallic vs non-metallic)

Quenched igneous rock

Extremely rapid cooling that produces a glassy texture

Light Silicates (nonferromagnesian)

Feldspars (Orthoclase/Plagioclase)

Pyroclastic rock texture

Fragmental

Vesicular igneous texture

Gas filled lava that cools as the gas escapes (rock bubbles)

Volatiles

Gases that easily come out of magma

Explosive eruptions

Higher silica and higher viscosity

Permeability

How easily water can drain through a rock

Porosity

How much space there is to store water within a rock

Shield volcanos

Huge , shallow volcanos (exclusively basaltic) (Hawaii)

Composite cone volcanos (Stratovolcano)

Large mountain sized volcanos (typically intermediate composition) (Mt. St. Helens)

Melt

Liquid part of magma

Hardness

Measure of a minerals resistance to scratching

Lava

Molten rock that cools at the surface

Magma

Molten rock that cools below the surface

Electrons

Negative charge (cloud around nucleus)

dark silicates (ferromagnesian)

Olivine, Pyroxenes, Amphiboles

Felsic (Granitic)

Quartz rich, lighter color, continental crust, low melt temp, high viscosity

Fine grained (aphanitic) igneous texture

Rapid cooling that produced small crystals

Crystal Form(Habit)

Refers to the minerals external geometry(shape)

Clastic rocks

Rocks formed by mineral grains bound together (classified by grain size)

Extrusive igneous rock

Rocks that form from lava at the surface

Intrusive igneous rock

Rocks that form from magma below the surface

Coarse grained (phaneritic) igneous texture

Slow cooling that produced large crystals

Flux melting

The addition of a fluid(flux) that lowers a rocks melting temperature

SiO4 Tetrahedron

The basic building block of all silicate materials

Color

The color of the rock (unreliable mineral indicator)

Nucleosynthesis

The creation of elements within stars

Magmatic differentiation

The process of partial crystallization of magma that changes the composition of the remaining magma

Lithification

The process that converts sediments into solid rock by compaction and cementation.

Cementation

The process where minerals/sediments crystalize together

Compaction

The process where sediments is squished together (loses water like a sponge)

Differential weathering

The process where softer rock gets eroded away and leaves harder rock exposed behind

Weathering

The process which degrades rocks without displacing them

Erosion

The process which rock particles are carried away by wind and water

Cleavage (vs Fracture)

The tendency(or lack) of a mineral to break along planes of weak bonding

Batholith (Volcano feature)

The term for the magma chamber after it has cooled and crystalized

Cinder cone volcanos

Tiny gaseous magma volcanos (sunset crater)

Covalent Bond

Two or more atoms sharing an electron

Porphyritic igneous texture

Variable cooling that produces many sizes of crystals

Pyroclastic flow

Volcanic ash and debris that is shot upwards out of a volcano then lands and spreads down the volcano

Lahar

Volcanic mudflow that usually results from melted snow on a volcano

Intermediate (Andesitic)

a medium level of silica content, intermediate viscosity, medium melting temperature

Aa

broken jumbles of sharp lava fragments with rough edges

Specific Gravity

compares weight of mineral to an equal volume of water

Nucleus

contains most of the mass of the atom

Mafic (Basaltic)

lots of iron and magnesium, darker color, oceanic crust, high melt temp, low viscosity

Non-Clastic rocks

rocks that are formed from evaporation, precipitation, or biological processes (classified by chemical composition)

Volcanic neck (volcano feature)

the upper part of the pipe that connects the magma chamber to the top of the volcano