oceanography

great circle
intersection of a plane passing through the center of the earth with the surface of the earth
nautical mile
unit of length equal to 1852 m or 1.15 land miles or 1 minute of latitude
projection
a system of projecting lines of latitude and longitude onto a plane surface to create a map with specific physical properties
bathymetry*
study and mapping of seafloor elevations and the variations of water depth; topography of the sea floor
polaris
north star
zenith
point in the sky that is immediately overhead
greenwich mean time
universal time; along the prime meridian
reservoir
a source or place of temporary residence for water
hydrologic cycle
movement of water among the land, oceans and atmosphere due to vertical and horizontal transport, evaporation and precipitation 
residence time
(think reservoir); mean time that a substance remains in a given area before being replaced
hypsographic curve
graph of land elevation and ocean depth versus area
radar
system of determining and displaying the distance of an object by measuring the time interval between transmission of a radio signal and reception of the echo return
lonar
navigational system in which position is determined by measuring the difference in the time of reception of synchronized radio signals
sublimation
transition of a substance from its solid state to its gaseous state without becoming a liquid
transpiration
process by which plants return moisture to air
Global Positioning System
a worldwide radio-navigation system consisting of twenty-four navigational satellites and give ground-based monitoring stations.
half-life
time required for half of an initial quantity of a radioactive isotope to decay
Tropic of Cancer
23 1/2 North
summer solstice
time of the year when the sun stands directly above 23 1/2 north latitude
Tropic of Capricorn
23 1/2 South
vernal equinox
directly above equator
latitude
parallel to the equator (north/south)
longitude
east or west of prime meridian (vertical)
prime meridian
meridian of 0 degrees longitude
international date line
an imaginary line through the pacific ocean (180 longitude)
inner core
inner most region of earth; 1222km thickness; solid; metallic
outer core
surrounds inner core; thickness = 2258km; liquid flows with speeds of about 1 km/year; metallic
mantle
main bulk of earth between crust and core; thickness – 2866km; solid but deformable; flows slowly 
crust
outer shell of the solid earth; continental thickness is about 40km (has granite); oceanic crust thickness is about 7km (has basalt)
seismic waves
how we know the internal structure of the earth; elastic waves created by earthquakes
lithosphere
strong rigid surface shell, consists of the crest and the upper mantle fused together
asthenosphere
layer below the lithosphere; temperature and pressure conditions leads to partial melting of the rock
p-wave
(aka primary wave) a type of seismic wave that can propagate through liquid; fast; think of a slinky
s-wave
(secondary wave) type of seismic wave; cannot propagate through liquid; slow; think of a rope
refraction
change in direction/bending of wave
isostasy
mechanism by which areas of the Earth’s crust rise or subside until their masses are in balance, “floating” on the mantle
ridge
long, narrow elevation of the sea floor with steep slides and irregular topography; if their mountain ranges are steep and narrow = ridge
rise
long, broad elevation that rises gently and generally smoothly from the sea floor; if their mountain ranges are gentler and broad = rise
trench
long, deep ; narrow depression of the sea floor (associate with subduction zone)
convection cell
the circulation of fluid in the asthenosphere
seafloor spreading
movement of crustal plates away from the mid-ocean ridges; process that creates new crustal material at the mid-ocean ridges; results in spreading center
subduction zone
plane descending away from a trench and defined by its seismic activity, interpreted as the convergence zone between a sinking plate and an overriding plate
sediment
organic and inorganic matter that accumulates in loose form
core
vertical, cylindric sample of bottom sediments, from which the nature of the bottom can be determined
dipole
a magnetic field like the Earth’s; has two opposite poles
polar reversal
north magnetic pole becomes south (or vice versa)
spreading centers
create magnetic stripes on the seafloor
2.250 x 108 years
the period of time during which the present oceans have been created
where is measured heat flow greatest along the oceanic crust?
in the center of ocean basins nearest the mid-ocean ridges
divergent plate boundary
two plates that are moving apart from one another
convergent plate boundary
two plates that are converging or colliding with one another
transform fault boundary
fault with horizontal displacement connecting the ends of an offset in a mid-ocean ridge
guoyant
submerged, flat-topped seamount
sonar
method or equipment for determining by under water sound the presence, location or nature of objects in the sea; derives from sound navigation & ranging
continental shelf break
zone along which there is a marked increase of slope at the outer margin of a continental shelf
continental slope
relatively steep downward slope from the continental shelf break to depth
shelf
the zone bordering a continent
submarine canyon
relatively narrow, V-shaped, deep depression with steep slopes, the bottom of which grades continuously downward across the continental slope.
turbidity current
dense, sediment-laden current flowing downward along an underwater slope; disposes turbidite
continental rise
gentle slope formed by the deposition of sediments at the base of a continental slope
abyssal plain
flat ocean basin floor extending seaward from the base of the continental slope and continental rise
abyssal hill
low, rounded submarine hill less than 100 m high
fringing reef
reef attached directly to the shore of an island or a continent and not separated from it by a lagoon
barrier reef
coral reef that parallels land but is some distance offshore, with water between reef and land
atoll
ring-shaped coral reef that encloses a lagoon in which there is no exposed preexisting land and which is surrounded by the open sea
island arc system
chain of volcanic islands formed when plates converge at a subduction zone
which of following statements is an accurate in regards to the use of satellite altimeters to measure bathymetry?
the gravitational anomaly due to subsurface bathymetric features causes the sea surface to be elevated or depressed, which is then measured using radar.
lithogenous sediment
sediment composed of rock particles eroded mainly from the continents by water, wind and waves; coming off the land and also from volcanoes
hydrogenous sediment
sediment formed from substances dissolved in seawater
biogenous sediment
shell and coral fragments as well as hard skeletal part of Plankton
cosmogenous sediment
particles from space
the thickest ocean sedimentary deposits are found where?
near continental margins
foraminifera
minute, one-celled animals that usually secrete calcareous shells
carbonate
a sediment or rock formed from the accumulation of carbonate minerals precipitated organically or inorganically
lysocline
depth where calcium carbonate begins to dissolve
carbonate compensation depth (CCD) 
the depth at which the amount of calcium carbonate preserved falls below 20% of the total sediments; no calcium carbonate will be deposited below this depth
phosphorite
a sedimentary rock composed largely of calcium phosphates; used to produce phosphate fertilizers
manganese modules
lumps found on the deep ocean floor; 18% manganese, 17% iron, with smaller amounts of nickel, cobalt and copper
continental shelf
flat borders of varying width that slope very gently towards the ocean basin; edge of continent
coccolithophore
microscopic, planktonic alga surrounded by a cell wall with embedded calcareous plates
diatoms
microscopic unicellular alga with an external skeleton of silica
radiolarian
single-celled protozoans with siliceous skeletons
red clay
fine rock powder blown out to sea by wind and swept out of the atmosphere by rain, may remain suspended in water for many years
calcereous ooze
fine-grained deep-ocean biogenous sediment containing at least 30% calcereous tests, or the remains of small marine organisms
Under which conditions do calcium carbonate shells dissolve more rapidly?
all of the above (at high pressure, in low pH water, in cold water)
covalent bonds
chemical bond formed by the sharing of one or more pairs of electrons
hydrogen bonds
weak attraction between the positively polar hydrogen of one water molecule and the negatively polar oxygen of another water molecule
moho
a physical boundary between crust and mantle
reservoirs are water frozen in icecaps and glaciers is not considered a reservoir because it is frozen. T/F?
false
latent heat of fusion
amount of heat required to change the state of 1 g of water from ice to liquid
latent heat of vaporization
amount of heat required to change the state of 1 g of water from liquid to gas
heat capavity
quantity of heat required to produce a unit change in temperature in a unit of mass material
cohesion
molecular force between particles within a substance that acts to unite them
surface tension
tendency of liquid surface to contract owing to bonding forces between molecules; measure of how difficult it is to stretch or penetrate the surface of a liquid
vicsosity
resistance to motion or internal friction
conduction
transfer of heat energy through matter by internal molecular motion
convection
transmission of heat from a heated gas or liquid, vertical circulation
radiation
energy transmitted as rays or waves, without the need of a substance to conduct energy
absorption
taking in of a substance by chemical or molecular means; changing of sound or light energy into some other form
attenuation
caused by absorption, scattering and divergence, the decrease in the energy of a wave or beam of particles occurring as the distance from the source increases
sound shadow zones
area of the ocean into which sound does not penetrate because the density of the water refracts the sound waves
sofar channel
natural sound channel in the oceans in which sound can be transmitted for very long distances; depth of minimum sound velocity
polar molecule
a molecule with unbalanced electrical charge; 105 degrees