Earth Systems Exam 1: Chapters 1-5

continental drift

the gradual movement and formation of continents: Alfred Wegener

Convection

the vertical movement of heat or other properties by massive motion within the atmosphere

Paleo-magnetism

When rock cools and solidifies, their magnetic alignment is frozen into place, creating permanent magnetic records.

Wadati-Benioff zones

The creation of ocean trenches and island arcs are linked to seismic activity and tectonic plate movement.

Outermost chemical layer of the earth:

crust

Middle chemical layer of the crust:

mantle

Innermost chemical layer of the crust:

core

outermost physical layer of the crust:

Lithosphere: oceanic and continental

second physical layer of the crust:

Athenosphere

third physical layer of the crust:

Mesosphere: lower mantle

4th and 5th physical layers of the crust:

Inner and Outer core: outer core is the only entirely liquid layer of the earth

Convergent boundaries

high density plate pushed beneath a more buoyant plate: Subduction. Oceanic-Continental and Oceanic-Oceanic.

Divergent Boundaries

Creates mid-ocean ridges and continental rift zones.

Transform Boundaries

Mostly found around mid-ocean ridges, lithosphere boundaries slide past each other.

The Wilson cycle

Outlines ongoing origin and breakup of super continents. 3 theories: The ridge-pull hypothesis, Slab-pull (best hypothesis today), and gravitational sliding.

Hotspots

an area in lithospheric plates where molten magma breaks through and creates a volcanic center, islands in ocean, and mountains on land.

Classic definition of a mineral

1: naturally occurring 2: inorganic 3: solid at room temp. 4: regular crystal structure 5: defined chemical composition

Rock

substance that contains one or more minerals/mineraloids. 3 Types: igneous, sedimentary, metamorphic.

Formation of minerals

1. Precipitation directly from a water solution with a temperature change. 2. Crystallization from magma with a temperature change 3. Biological precipitation by the action of organisms.

The Olivine Family

Silicate minerals, primary mineral in mantle rock. Solidifies into igneous rock, a mafic material.

The Pyroxene Family

Silicate mineral: another mafic mineral, found in both igneous and metamorphic rocks.

The Amophibole Family

Silicate mineral: found in both igneous and metamorphic rocks, have a long-bladed crystal habit.

Sheet Silicates

Silicate mineral: micas and clays, quartz and feldspar very abundant

Carbonates and phosphates

Non- Silicate minerals, also referred to as salts

Minerals are ID'ed by:

luster, color, streak, hardness, crystal habit, cleavage, fracture, and special properties like effervescence.

Igneous rocks are classified by:

Texture: coarse-grained (phaneritic), fine-grained (apantic), or mixed (porphyritic).
Composition

The different groups of igneous rock composition:

1: felsic 2: intermediate 3: mafic 4: ultramafic

Bowen's Reaction Series

describes the temperatures at which minerals crystallize and melt. All minerals will crystallize by 700 C and melt by 1,250 C.

What are the components of magma and lava?

melt, solids, and volatiles (gaseous components)

Solidus

melting point of rock at given pressure.

Where does most volcanism occur on Earth?

On the ocean floor along mid-ocean ridges

What are the unique properties of water?

Polarity, adhesion, and cohesion.

Mechanical weathering

physically breaks apart rock through pressure, temperature, freeze/thaw, plant/animal activity, and/or salt evaporation.

Chemical weathering

water, oxygen, and other reactants chemically degrade the mineral components of bedrock and turn them into water soluble ions through hydrosis, dissolution, oxidation, and/or erosion.

What is a soils characteristics determined by?

1. Mineralogy of parent material 2.topography 3.weathering 4.climate 5.organisms in the soil.

What are the main categories of sedimentary rocks?

Clastic (detrial) and Chemical

How does Lithification turn sediment into rock?

Decomposition, compaction, and cementation

Chemical sedimentary rocks

formed by processes that do not directly involve mechanical weathering and erosion

Inorganic sedimentary rocks

made of minerals precipitated from ions dissolved in solution, created without aid of living organisms

Biochemical sedimentary rocks

formed from aquatic shells and bodies, usually from organic material lithified underwater.

Classification of sedimentary rocks

1: Determine makeup 2: Grain size 3: Rock description 4: Rock name

Sedimentary Structures

Visible textures/arrangements of sediments within a rock. Ex: bedding planes, graded bedding, plane beds, ripples, dunes, anti dunes, bioturbation, mud cracks.

Marine Depositional Environment

completely submerged in seawater.

Continental Slope Depositional Environment

not common in rock record: lower and upper slope on beach

Littoral zone Depositional Environment

The beach: tidal flats, reefs, lagoons, deltas

Terrestrial Depositional Environment

Diverse: Fluvial, Alluvial, Glacial

Facies

classify sedimentary rocks by physical, chemical, and biological properties.

The four earth systems

Geosphere, Hydrosphere, Biosphere, and Atmosphere

The types of boundaries between plates

divergent: oceanic spreading center, cont. drift zones. convergent: oceanic-continent, continent-continent, oceanic-oceanic. transform: continental transform fault, mid ocean ridge transform fault.

Intrusive rock

Plutonic, forms within earth's interior and cools within the earth, forming large crystal sizes

Extrusive rock

Volcanic, forms outside of earths interior, creating small crystal sizes

Textures of Igneous rock

pegmatic, phaneritic, aphantic, glassy, porphyritic, vesicular, and pyroclastic (slow to fast cooling)