EPSI
Granite
continental crust density: 2.7/2.8 g/cm3
Layers of earth
crust, mantle, outer core, inner core - increasing density into the core
bio-intermediate
depleted by biological processes, but never becomes limiting for biological activity
New oceanic lithosphere forms at
divergent boundaries - mid ocean ridges
Basalt
oceanic crust density: 2.9/3.0 g/cm3
Physical state of matter
solid, liquid, gas, plasma
Asthenosphere
The soft layer of the mantle on which the lithosphere floats. Hot, plastic, upper mantle
Mesosphere
The strong, lower part of the mantle between the asthenosphere and the outer core. Hot, plastic, strong, lower mantle
Paleoceanography
The study of the history of oceans in the geological past - using environment nodes with different proxies
Sound travels ___ times faster in the water than air
4
___% of the world population lives close to the ocean
40%
terrigenous covers __% of all ocean floor
45%
divergent boundary
two plates move away from each other - make new lithosphere - mid Atlantic ridge
transform boundary
two plates move past each other in opposite directions - conserve lithosphere - San Andreas fault
convergent boundary
two plates move toward each other. - destroy old lithosphere (subduction) - trenches, Himalayas
Biogenic covers ___% of all ocean floor
55%
___ % of earth is covered by water
70%
Mantle density
3.3 g/cm3
Oozes contain __% of biogenesis material
30%
The average salinity of the ocean is ___
35 PSU (35 g/kg)
Science uses what system of measurement?
(SI units) international system of units
Molecules
- chemically bonded atoms
submarine canyon
- erosion through shelf and slope - transport sediment from rise out into abyssal plains
Proposal 1
- from the inside Water originated from inside the watch. Primary source is volcanic outgassing
volcanogenic sediment
- generate along active margins and around large volcanic ocean islands
covalent bond
- molecular - sharing electron pairs between atoms - stable balance of attractive and repulsive force between them
Carbonate Compensation Depth (CCD)
- more CO2 can dissolve in cold water which makes it more acidic—> makes more calcium carbonate —> which dissolved calcium carbonate in deeper waters
manganese nodules
- most significant authigenic sediment - metal rich sediments - pebbles or stones
Challenger Expedition
- on the HMS challenger - circumnavigated the globe - was a scientific exercise that laid the foundation of oceanography
How many magnetic plates are in the lithosphere?
-14 major plates - 50 total
Earthquakes
-concentrated in few "strips" of lines near surface (cracks or boundaries between ridges areas) - at trenches earthquakes get deeper with distance
gyres: convergence
-in areas of downwelling -change in sea surface height induces pressure gradient force directed from high pressure to low-pressure -balance of pressure gradient force with Coriolis force leads to circulation motion around high pressure system
Gyres: divergent
-in areas of upwelling -changes in sea surface height induces pressure gradient force directed from high pressure toward low pressure -balance of pressure gradient force with Coriolis force leads to circular motion around low pressure system
Proposal 2
-introduced by meteoroid impacts Water arrived from outer space via meteoroid/asteroid impacts
density of pure water
1 gram per cubic centimeter
bond strength
1. Ionic 2. Covalent 3. Hydrogen bond
Hydrogenous (authigenic) covers __% of all ocean floor
<1%
Aristotle
A Greek Philosopher and scientist - first recorded observations in the distribution, organization and habits of marine life
Salinity
A measure of the amount of dissolved salts in a given body of water - affects density of water - more salty, higher density
Anion
A negatively charged ion
Cation
A positively charged ionic
scavenged
Affected by non biological processes
Thickensss if the sediment depends on
Age of seafood since formation and sediment rate
continental drift
All continents fit together as a single land mass (Pangaea)
Isostatic Balance
Balance due to density lithosphere pieces balanced in asthenosphere
Scientific method (empirical)
Based on observation and measurements
submarine landslide
Burden of sediment breaks and rushes down continental slope - generates rapid response of sea level (tsunamis)
Atom
Cannot be brown down into simpler parts by chemical means
polar covalent bond
Between two atoms where electrons forming bond are unequally distributed - cause slight electrical dipole - one positive, one negative
biogenic ooze
Biochemical material (shells and skeletons) destruct (dissolve before burial) and mix with terrigenous sediments (bilution) - uncommon near continents due to few nutrients
Lithosphere
Cold, strong, crust and upper mantle
polyatomic molecule
Consist of different atoms
Diatomic molecules
Consist of two of the same atoms
Scientific Method (Accurate)
Consistent and non arbitrary
Lithosphere is consumed at
Convergent boundaries (subduction) Deep sea trenches
abyssopelagic zone
Deeper than bathypelagic - abyss
bio-limiting
Depleted a lot, becomes a limiting factor for biological activity
Turbidity
Distinct layer of sediment different from the layer below or above
Cori okie effect
Earth is spinning on axis - Northern hemisphere: deflection to the right (counterclockwise) - southern hemisphere: deflection to the left (Clockwise) - no deflection on the equator
Charles Darwin
English natural scientist -5 year voyage on H.M.S beagle
Hotspots
Form independent of tectonic plate boundaries - fed by underlying mantle that is hot - Hawaiian island chains
continent-continent convergence
Forms giant mountain ridges, volcanic island arcs
Biogenic Sediment
From biological sources - dead algae, fecal pellets
Chemogenic Sediments
From precipitation of minerals - authigenic
volcanogenic sediment
From volcanism - volcanic ash
Convection
Help lithosphere Recycling - (heat transfer by moving "fluid")
Convection loop
Hot air rising at equator, travel to poles - low pressure at poles - high pressure at equator
Sea surface height
Increases as you go west
Melting temperature
Increases dramatically as pressure increases with depth
Alfred Wagner
Initiated the plate tectonic theory - advocates the existence of continental drift - explained location of most earthquakes, volcanoes etc
Metallic core
Iron rich inner part of the planet
Luigi Marsigli
Italian scholar and natural scientist - wrote the first oceanography book
Temperature
Kelvin (K) or Celsius
Earth's magnetic field
Made by convection in outer core - dominantly dipolar (opposite charge) - magnetic poles reverse locations
Marine snow composition
Made up of aggregates of smaller particles held together by sugary mucus transparent extracellular polysaccharides (TEPs)
What is the deepest tench
Mariana Trench
bimodal distribution
Most of earths surface is elevated either a little above sea level or 2-6km below sea level
Electrons
Negative charge - little mass, occupy the most space
bathypelagic zone
No sunlight at all - midnight
latent heat
No temperature change with added/subtracted heat
Major gyres
North Atlantic, South Atlantic, North Pacific, South Pacific, Indian Ocean
Fridtjof Nansen
Norwegian explorer who observed ice in the Arctic Ocean moving to the right of the wind direction Was on expedition that attempted to travel to the north pole. Went on ship called the Fram - predicted there is an ice drift
Bio-unlimited
Not affected by biological activity
ocean-continent convergence
Ocean subduct under continent - forms mountains and volcanoes
ocean-ocean convergence
Ocean subducts under ocean - forms volcanic island arcs, trenches
Cosmogonies sediment
Outer space - cosmic dust
Pebbles, sand, clay
Pebbles: hard to transport Sand: middle Clay: easy to
Ocean depth zones
Pelagic zone
Photosynthesis
Plants and bacteria make simple organic compounds (sugar) from H2O, CO2 and light energy
Authigenesis
Process whereby a mineral or sedimentary rock deposit is generated where it is found or observed - forms during sedimentation by precipitation or crystallization
Passive margins (Atlantic style)
Produced over geological time. Mark the sites where continents have rigged apart to become seperated by an ocean - broad flat shelves
Nucleus
Proton (+ charge) Neutron (uncharged) - high mass, small
PH scale
Quantify how acidic a solution is - lower number= more acidic
Why is the ocean blue?
Quantity of light changes; it decreases with depth - wavelength decreases and energy increases as you move from red to violet light across the spectrum
Pycnocline
Rapid density change per depth
Halocline
Rapid salinity change per depth
Thermocline
Rapid temperature change per depth - thin layer in the ocean
Genous
Refers to the local origin of the sediment (from land)
Silicate rock
Rock mantle
What do we use to map the ocean sea floor?
Satellite altimetry or multi beam sonar
terrigenous sediment
Sediment eroded from the land/continents - rivers, dust, icebergs
Bond
Share one electron
Speed of sound in water
Sound waves can travel through any substance - water particles are closer together and can transmit quickly creating vibration energy
Archimedes' Principle
States that the buoyant force is equal to the weight of the fluid displaced by an object. - any object in a fluid displaces the amount of fluid equivalent to its mass
Factors influencing density
Temperature, salinity
Ekman transport
The balance between friction and Coriolis effect
hadal zone
The deepest zone of the ocean - trench
seismic waves
The energy in an earthquake that move outwards from the focus and make the ground quake
epipelagic zone
The lighted, or photic, zone in the ocean. - sunlight zone
Fram Strait
The passage between Greenland and Svalbard
focus
The point in earths interior where earthquake energy is released
Respiration
The process by which cells break down simple food molecules to release the energy they contain.
Subduction
The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.
Genic
The process that formed the sediments (by biological)
Thermal convection in water
The transfer of heat from one place to another by the movement of fluids - important in ocean circulation as water is cooked at the pokes and heated at the equator
How is sea floor formed at mid ocean ridges?
Through uprising hit mantle material at spreading zones of ocean plates
Nansen's Fram Expedition
To to reach the geographical North Pole by using the natural East-west current of the Arctic ocean
Subtropical Convergence
Trade winds going parallel and opposite direction of westerlies - cause winds to converge
thermal converters
Transport heat through the movement of liquids
Ekman suction
Upwelling from equatorial diverge from trade winds Meant to replace water that is diverging from equator
mixed layer
Where active turbulence has homogenized some range of depths - shallowest at equator
Active margins (pacific style)
a continental margin that coincides with a plate boundary - narrow shelf adjacent to a deep sea trench
marine snow
a continuous shower of mostly organic detritus falling from the upper layers of the water column - exploiting energy from the light rich photic zone to the aphotic zone below
polarity of water
has polar covalent bonds; H is partially positive, O is partially negative
Mass
kilogram (kg)
Mid ocean ridges
longest chains of mountains on the ocean floors
length
meter (m)
Concentration
moles/volume
Continental crust vs. oceanic crust
oceanic crust is denser so it will sub-duct under continental crust. - the continental crust (granite) is lighter (less dense) but thicker than the oceanic (basaltic, more dense (thinner) crust
geostrophic current
oceanic flow in which the pressure gradient force is balanced by the Coriolis effect
heat capacity
the amount of heat needed to increase the temperature of an object exactly 1°C - water has a high heat capacity takes a lot of energy to heat up compared to other systems
Ionic bonds
the complete transfer of valence electron(s) between atoms - generate two oppositely charged ions
sensible heat
the heat we can feel and measure with a thermometer
Isostasy
the state of gravitational equilibrium between Earth's crust and mantle such that the crust "floats" at an elevation that depends on its thickness and density
Oceanic crust
thinner, more dense, younger crust making ocean floor
mesopelagic zone
where light can penetrate, yet without the intensity to support photosynthesis - twilight zone