Oceanography Exam 1 Study Guide

What is oceanography?

the study of the worlds ocean with a broad field encompassing geological, physical, chemical, and biological oceanography as well as marine engineering

what are two meteor expeditions

scripps institution of oceanography and woods hole oceanographic institution (hoie)

what is an argo float

floats that dive up to 2,000 m and stay for 10-14 days
* they can sink, drift, collect data, float back to the surface, and send data to satellite

measure temperature, saltiness, and depth

what were earth’s sources of water?

mantle and asteroid

what is a half life?

a half life how long it takes to loose half of what was started with

if 400 atoms start off how many are left after two afterlives

400/2= 200/2= 100

what are three important parts of the hydrologic cycle

evaporation, transpiration (water that goes through plants into air), and sublimation (solid water that turns directly into water vapor)

what takes up the most percentage of fresh water on earth

ice caps and glaciers (biggest percentage)

what is the second biggest percentage of freshwater

freshwater lakes

what is the smallest amount of fresh water

rivers

with all the freshwater what is the order from most to least percentage of all freshwater on earth

ice caps and glaciers, groundwater?, freshwater lakes, soil moisture, atmosphere, rivers

what is residence time

how long water stays in a reservoir (or body of water) on average

large reservoirs like lakes and bathtubs have what type of residence time

they have a long residence times because they have more water and a smaller flux

small reservoirs like a cup of water or a pipette of water have what type of residence time

they have short residence times because they have less water and a larger flux

what are the five world oceans and where are they

artic ocean (up north in the artic)

southern ocean (down south near antartica)

indian ocean (right of africa left of australia below euraisa)

pacific ocean (left of the americas and right of eurasia and oceania)

atlantic ocean (between the americas and europe and africa)

what helps the scientists figure out what is below the ground

seismic waves, specifically those that come from earthquakes
they can see how long it takes for the seismic waves to go from where they started down into the earth and based on their actions figure out whats in between

what are the two types of waves that are used

primary (p) waves and secondary (s) waves
primary waves are faster, compressional, and can go through solids liquids and gasses
secondary waves are slower, shear, and can only go through solids

what are the 3 layers of the earth

surface layer is the crust, middle layer is the mantle, and center is the core

what is isostasy

because we are floating on magma, continents are balanced out by buoyancy, its likes something floating on water or a soft surface with another force balancing it

who do scientists figure out how fast the sea floor is spreading

magnetic stripes, magnetic field, and looking at things like ocean mountain ridges (hawaii)

the lithosphere is broken into three types of plates, what are they

divergent boundary, convergent boundary, and transform boundary

what makes a divergent boundary divergent

the plates move in different directions away from each other

what makes a convergent boundary convergent

the plates move towards each other

what makes a transform boundary transform

the plates slide against each other

what is subduction

when one plate goes under another plate

the subduction zone is a line of volcanoes

what are the three types of convergences

ocean-ocean (density chooses which plate goes up or down, older sea floor will go down)

ocean-continent (line of mountain belt, active volcanoes)

continent-continent (force squeezes against each other, mountain belt gets taller)

if there is a line of volcanoes and only one is active which one is the oldest (like hawaii)

casued by mantle plumes, the one farther away is the oldest, the one closest is the youngest, this helps scientists determine what direction and how fast the ocean floor is spreading

what are the different areas on the mantle convection

island arc (like hawaii, the islands are formed by active and old unactive volcanoes in a line, magma plumes)

mid-oceanic ridge (line of mountains formed in the ocean because of sea floor spreading and hot magma rising)

earthquakes (happen when plates move either away from each other, towards each other, or next to each other)

subduction zone (area where one plate goes under another plate when moving)

in an ocean basin cross section what are the different areas

the continental shelf (shallow and flat by the coast)

slope (the drop off from the shelf into deeper parts of the ocean)

mid oceanic ridge (line of mountains in ocean)

sea mounts (large underwater mountain, not in a line)

trench (subductions can create deep trenches, but not all do)

it goes from shelf to slope to trench

what are the two terms to determine distance from shore

neritic (area close to shore line)

pelagic (area farther from shore, deep ocean)

how to determine where you would find certain sediments in the ocean

big chunks of rock would settle near the coast line in the neritic area

smaller particles are easier to travel farther away so would end up in the pelagic area

ex: a boulder would be in a neritic area while clay would most likely be in a pelagic area

what are two ca shells

foram and coccolith

build shells out of calcium

what are two si shells

diatom and radiolaria

made of silica

which two shells are more animal like

foram and radiolaria

they move around and eat, they are on the larger size

which two shells are more plant like

coccolith and diatom

they use photosynthesis, grow, and eat, they are a smaller size

global distribution of marine sediments follow what

they follow similar patterns to that of plate tectonics

an example is that calcium carbonate follows the same s pattern in the atlantic ocean that the broken plates do

what is the lysocline line

this is the line where dissolution begins for creatures like foram and diatom

what is the carbonate compensation depth

this is the line where dissolution occurs fully, no creatures like foram or diatom would survive below this line

where are foram and diatom found

they are found on ocean mountains in shallower areas

why are some foram and diatom found while others dissolve

they use carbonate ions and calcium to form their shells which are calcium chloride, this process needs lots of carbonate ions

in deep water there are not as many carbonate ions so if the beings go down there they need to substitute the amount of ions with calcium which then causes them to dissolve

in shallow water there are lots of carbonate ions so the shells can be formed and survive

in the chart there are two lines for the different minerals and how much of each of them are needed, when a being crossed that line the carbonate ions need to be preserved, it splits into two minerals

these minerals need to be stable, so if theres more carbonate ions than the minerals need they will survive, if there arent enough and are below carbonate compensation the shells will dissolve fully

what are other parts of the hydrologic cycle

sublimation, precipitation, runoff, condensation, evaporation, groundwater transpiration

what are gas hydrates

methane and water combined under high pressure and low temperature

what are manganese nodules

small round shaped rocks composed of layers of iron and manganese hydroxides that lie on the ocean floor in certain areas around the coast