Oceanography Review Midterm 1
-Ocean is part of your daily life
● Provides oxygen you breath
● Influences the weather
● Takes carbon pollution
● Provides food, and energy
● provides the oxygen you breath
-Most of the Earth’s water is in the ocean (97%)
● Measures how far a point is north or south of the equator.
● Measures how far a point is east or west of the prime meridian (reference line) -Echo sounding
● Waves bouncing off the submarine, bouncing off the seafloor
● Depth=V( T ⁄ 2)
● V=sound wave velocity
● T=round-trip time
-Satellites bouncing radar off the ocean surface is used to measure its height it works b/c the vertical position of the satellite relative to the center of the Earth Don't forget about the age old question of How can language obscure meaning?
We also discuss several other topics like What is the ionic basis for the resting membrane potential?
-Satellite altimetry used radar (microwave/radio waves) to measure sea surface height -V⁄A= 1.37X
-What is the age of the Ocean & how we do know
● 4 billion years and because of CO2 from the atmosphere dissolved into the Oceans and was removed as carbonate sediments in the Earth’s crust
-How did Earth get its water (and ocean) If you want to learn more check out In chemistry, what is the function of hybridization?
● Outgassing of volatiles from Earth’s interiors or Icy comets hitting Earth bring water -Why does Earth have a liquid ocean but not the other planets in our solar system? ● Because Earth has a habitable zone
-What did the earliest ocean and atmosphere look like on Earth?
● Had little oxygen We also discuss several other topics like How did kepler challenge the earth centered model?
-Beginning of universe happened by the Big Bang which was the start of space and time as a point source of mass and energy followed by a massive explosion. The explosion released sub-atomic particles and energy, then the element hydrogen formed If you want to learn more check out What is the purpose of heuristics?
-Radioactive Decay: acts like a clock
● Forms of chemical element with the same number of protons but different numbers of neutrons
● Isotopes are unstable and lose energy by emitting radiation called Radioactive decay -Stars and planets are contained within galaxies
● A galaxy is a rotating aggregation of stars, dust, and gas (our galaxy is the Milky way) GAS+DUST=NEBULAE
-Stars converted hydrogen(H) to helium (He) to heavier elements by nuclear fusion through age they are called nucleosynthesis
● Hydrogen (H), Helium (He)
● Water (H2O) Methane (CH4) Ammonia (NH3)
● Silicates (like SiO4) Oxides
● Iron (Fe) Nickel (Ni) cause the movement of tectonics
-What is the difference between the continents and the ocean floor?
-What is the anatomy of an ocean basin?
-What physical forces shape the ocean basin?
-What is plate tectonics and what is the scientific evidence for this theory? -What happens at the boundaries between plates?
-Alfred Wegener Don't forget about the age old question of Who were the patriots during the american revolution?
● Suggested that continents were originally all together in a giant landmass (Pangaea) -Fossil Evidence
● Wegener noted that fossils of Mesosaurus were found in Argentina and Africa but nowhere else in the world. While fossils ferns, Glossopteris were found in all the southern landmass.
● There was matching rocks across the oceans
-Earthquakes can tell us about the structure of the Earth with a device called seismometers -Seismometers
● Record different types of energy waves caused by earthquakes
1. Surface waves move along Earth’s surface
2. Body waves travel through the Earth. It can be used to analyze Earth’s structure Types of Body Waves
1. P-waves(primary) particle motion is in direction that wave is traveling. The traveling pattern of compression and rarefaction SOLID, LIQUID, GASES
2. S-waves (secondary) particle motion is perpendicular to direction that wave is traveling sideways motion ONLY IN SOLIDS
-Crust the uppermost, lightweight layer
-Mantle beneath the crust, most of Earth’s mass
-Lithosphere the crust and the upper portion of the mantle
-Asthenosphere hot, partially melted layer of upper mantle
-Lower Mantle more dense than asthenosphere, flows much more slowly -Outer Core dense liquid
-Inner Core solid
-Earth’s magnetic field thought to arise from fluid motion in the outer core (convection currents) couple with the Earth’s rotation
● Characterized by mid-ocean ridges and the idea that the seafloor was spreading. New crust being added at the mid-Atlantic ridge
● Younger oceanic crust would be closer
● Older oceanic crust would be farther
● Where the old crust is removed
-Tectonic system is powered by heat (convection currents) arising from radioactive decay in Earth’s interior and by gravity (pulling the plates back down)
● are made of many rocks but compositionally are very similar to granite which are light meaning less dense
● beneath the sediments (oceanic crust) are made of basalt which is heavier meaning more dense
● Light things float and heavy things sink and it is a consequence of gravity -Divergent margin
● Move away from one another (ocean ridge, spreading center)
● New ocean crust is created (makes oceans bigger)
● Outgassing: gases added to hydrosphere and atmosphere
● Chemicals from mantle added to ocean-black smokers
● Heat is added to ocean
● Move toward one another (subduction zone, collision zone, trench)
● Ocean-Ocean Convergent Margin: Continents are born
● Continent -Continent Convergence: shows the convergence of two continental plates. Neither is dense enough to subduct. Their compression and folding uplift the plates edges to form the Himalayas
● Ocean -Continent Convergence: The more dense oceanic plate gets subducted beneath the light plate
● Slide past one another (transform margin)
● Crust is neither added or removed
● No volcanos just earthquakes
● They are formed b/c ocean crust breaks in different places as it is pulled apart by subducting plates
● Margins are coincident with plate boundaries and hence volcanic and earthquake activity (pacific type) (move)
● Margins do not coincide with plate boundaries (atlantic) (dont move)