Oceanography 100 Final SDSU Exam Questions And Answers 100% Verified

Oceanography 100 Final SDSU Exam Questions And Answers 100% Verified How was the solar system formed? - answer-a supernova (explosion of a start when it runs out of fuel) -4.6 billion years ago how was the earth formed? - answer-a nebula made of gas and dust -was formed 4.5 billion years ago how did oceans form? - answer-A volcanic expulsion - rained for thousands of years -hit by an icy comets -volcanic out gassing and ice from comets when did life form? - answer-3.7 billion years ago how long have animals been around for? - answer-600 million years ago how long has photosynthetic organisms been around? - answer-2.5 billion years ago what is the lithosphere? - answer-crust and top mantle -outer most layer of the earth -the ground on which we walk on -(rigid and brittle) -(100km) What is the asthenosphere? - answer-beneath the lithosphere -where convection is thought to occur -(hot, plastic region, 600km) what is the mesosphere - answer-outer core, inner core -(lower mantle) -core is made of Iron and nickel what is the order of the earth layer (from outer most to inner most) - answer1. Lithosphere (ridge) 2. Asthenosphere (plastic) 3. Mesosphere (ridge) 4. Outer core (liquid) 5. inner core (rigid) What is kinetic energy? - answer-Energy of motion what is heat energy - answer-Energy transfer of heat from hot to cold what is density? - answer-relationship between mass of a substance/how much space it takes up -when it is colder it is more dense -when it is warmer it is less dense what is the difference between oceanic crust and continental crust - answer-oceanic crust is (basalt) thinner and more dense -continental crust (granite) is thinker and less dense what is convection - answer-means of heat energy transfer -sinking of cold air because it is denser -rising of hot air because it is less dense Bioaccumulation - answer-as you go up the base of the food chain, the level of mercury is more concentrated at the top of the food chain than the base of the food chain -ex) bigger fish eat smaller fish with contamination -(little fish is contaminated, then bigger fish is contaminated because he ate little fish) Biodegradtion - answer-Process by which organic substances are decomposed by microorganisms -(plastic is NOT biodegradable) -nature can break it apart and can be used again photo-degradation - answer-when the sun breaks things down to make them smaller -plastic is broken down by the sun but only into smaller particles so animals confuse them for food -plastic enters out food chain by eating animals that have consumed plastic Diffusion - answer-molecules go from high concentration to low concentration -ex) when cooking pasta, the water diffuses into the noodles, making them bigger and more moist -ex) when using a diffuser, the high concentration would be the essential oil and then it transforms into mist, which would be the low concentration continental drift - answer-Pangea (super continent during early years of Earth -break up of continent= asthenosphere melts and pushes land apart -the initial hypothesis was by wegener and his evidence Eco sounding and Sonar - answer-(velocity of sound) * (time)/2 -shallowest in the middle of oceans seafloor spreading - answer-mid-ocean ridges -rocks rise from center and create plates ages of ocean floor - answer-youngest= mid ocean ridges -oldest= closer to coasts and continents (deeper) Earth's magnectic field - answer-rocks at ridges capture the energy of magnetic fields -get increasingly older as they move further away from ridge what is the world distribution of earthquakes? - answer-the distribution is not random, mostly at the pacific rim -generally happens at plate boundaries -earthquakes are mostly distributed in the ridges because when the oceanic lithosphere is going under the other oceanic lithosphere, the sliding of the rocks make the earthquake world distribution of volcano - answer-generally happens at convergent plate boundaries convergent boundary - answer-Subduction zones (forms trenches) -one plate overlaps another plate (comes together) - -----> <------- -ex) tsunamis, earthquakes, deep sea trenches -ex) Mt Fuji, Tonga, The cascades *both are coming together and one "ducks" underneath the other divergent boundary - answer-Mid-ocean ridges -2 plates move apart, magma comes up to create new crust -examples: East Pacific Rise, Mid-Atlantic Ridge, Iceland -Results: seafloor spreading, huge volcanic mountain chains -plates separate - <------ ------> Transform Boundary - answer-Plates slide by opposite directions horizontally -they connect oceanic ridges -found mostly in ocean, with exception of San Andreas fault on land - ^ / what are trenches - answer-deepest parts of the ocean -where one plate subducts (slab-pull) under the other -the plate subducting is the denser of the two -Mariana trench is the deepest what is our plate boundary here in San Diego? Where is it? - answer-San Diego lies on the San Andreas Fault -It is a transform boundary in what direction are we moving - answer-we are on the pacific plate -moving North to west what are hot spots? - answer-Deep mantle plume of hot rock -rises by convection and forms a volcano -Hot spots do not move, plates move instead (North west) -ex) Island of Loihi in Hawaii -southeast -newest Island passive margin - answer-continental shelf -(slope, rise, abyssal plain) -little tectonic activity (its located away from a plate boundary) - wide shelf (more sediment) -ex) Atlantic ocean Active margin - answer-subduction zone -trenches and narrow shelfs -erosional coasts and cliffs -located at a plate boundary -ex) Pacific ocean what is the average temperature of the ocean - answer4 degrees Celsius -(38 degrees Fahrenheit, almost freezing) -majority of the ocean is very deep and not exposed to sunlight and therefore colder what is the water molecule - answer-2 hydrogen (+) and 1 oxygen (-)- this is a covalent bond covalent bond - answer-share electrons between H and O -connects hydrogen to oxygen hydrogen bond - answer-connects H20 to H20 -binds all the water molecules together to form liquid or a solid (there is no hydrogen in gas forms) -the bond angle is 105 polarity - answer-electromagnetic -positive charge on one end (hydrogen) -negative charge on the other (oxygen) -called a dipole molecule because it has two poles