AICE Marine Science (Unit 2 Cram Sheet)

Core

Innermost, dense sphere made of iron and nickel.

Solid Inner Core

The solid part of the Earth's core.

Liquid Outer Core

The liquid part of the Earth's core.

Mantle

Hot, semisolid, molten rock capable of slow movement.

Viscous Asthenosphere

Part of the mantle capable of movement and deforming at high temperatures.

Crust

Outermost layer of solid rock.

Continental Crust

Thinner and denser crust made of basaltic rocks filled with iron and magnesium.

Granite

Type of rock found in the continental crust.

Theory of Plate Tectonics

The lithosphere is divided into plates that float independently and are in constant movement due to the viscous asthenosphere.

Geological Matching of Rock Formations

Evidence supporting plate tectonics where geology of rock formations matched.

Distribution of Fossils

Evidence supporting plate tectonics where fossils and organisms are distributed on coasts of many continents.

Paleomagnetic Stripes

Reversals in Earth's magnetic fields every 250K years due to new solidified rock having charged magnetite.

Divergent Boundary

Tectonic plates moving away from each other, creating new seafloor.

Transform Boundary

Sliding of plates against each other, with no crust destroyed or created.

Ocean Trenches

Narrow, deep canyons in seabed formed at subduction zones of convergent boundaries.

Mid-Ocean Ridges

Underwater mountain ranges with central valleys where new crust forms due to upwelling of magma.

Hydrothermal Vents

Openings in the ocean floor where cold ocean water is superheated by magma and forced out.

Abyssal Plains

Flat, sandy regions found between trenches and continental rise, formed due to seafloor spreading.

Volcanoes

Mountains with crater/vent where lava erupts.

hot vapor

gas rock fragments are forced through Earth's crust

convergent boundary

Tectonic plates moving towards each other, forming a subduction/destruction zone. where pressure builds up between oceanic and continental plates causing the crust to thin and magma to rise/erupt

lava

solidifies into new rock building a volcano, and sometimes islands

Ring of Fire

has high volcanic and seismic activity

earthquakes

sudden energy release from crust's movement

tsunamis

long, high-energy waves caused by seismic activity of earthquake or volcano

convection currents

fluid/air movement based on temperature/density: warmer, less dense rock rises above colder, denser rock, and as rocks cool, they sink; happening in a circular cycle

hydrothermal vent plume

the superheated, pressurized water rich in dissolved nutrients that comes from hydrothermal vents

weathering

gradual breaking down of substances into smaller pieces

erosion

material is broken down and transported to a new location

chemical weathering

chemical composition of rock is changed mostly by oxygen or water

physical/mechanical weathering

changes physical not chemical composition

organic/biological weathering

performed by living organisms

ice erosion

ice crushing rock

gravity erosion

the moving of rock through gravitational forces

wind erosion

wind blowing and picking up sediment

water erosion

water picks up sediment and carries them through runoff

sedimentation

the deposition(delivery) of suspended particles(sediments) to a new location

littoral zone

the area where the land meets the sea between the highest spring tide and lowest spring tide water marks

rocky shores

made of a rocky substrate; varies in slope and rock size; made of granite/igneous rock, resistant to weatherings

sandy shores

made of silica(loose sand deposits), gravel, and shells; formed by sandstone erosion and sand sedimentation

muddy shores

found in protected regions; least exposed and most resistant to weathering and erosion

estuaries

partially enclosed, brackish bodies of water; sheltered from erosion and weathering of waves

deltas

triangular areas at river mouths where land meets the sea

tides

periodic rise and fall of surface of water bodies

diurnal tide

1 high and low tide daily

semi-diurnal tide

2 high and low tide daily

tidal range/amplitude

difference between coastline's highest and lowest water mark

tidal surge

abnormally high coastal flooding from low pressure system

spring tide

Sun and Moon are aligned with Earth creating the greatest tidal range

neap tide

Sun and Moon are perpendicular to Earth, creating the smallest tidal range

currents

continuous, directional movement of seawater

surface currents

driven by global wind patterns

deep currents

thermohaline circulation - deep water circulator caused by density differences due to temperature and salinity changes

upwelling

movement of cold, nutrient-rich water from deep ocean to surface

global ocean conveyor belt

deep water currents facilitated by thermohaline circulation

El Nino

caused by Western winds stop blowing in their normal pattern, causing warm water to buildup on South American coast

La Nina

cooling phase after El Nino where stronger than average winds blow winds off the South American coast allowing for cold water from Humboldt current to upwell