Oceanography 001                                                                                                          West Valley College

R. Lopez

Study Questions 4: Continental Margins and Ocean Basins


1)       What was the significance of the HMS Challenger? (p. 88 of Garrison text)



2)       The Challenger Report provided the foundation for what field of science?




3)       The sea floor is broken down into what two categories?




4)       Continental Margins are the submerged edges of the _______________?



5)       List the properties for Passive margins and Active margins.




6)       Define both Continental Shelf and Continental Slope.




7)       What is the Shelf Break? .




8)       What are Submarine Canyons and what are the two theories regarding their origin?





9)       The geologic epoch that corresponds to the “Great Ice Ages” is



10)    The last glacial high stand occurred during this epoch ______ years ago.



11)    How low was sea level during the last glacial maximum?



12)    Where was the shore line off San Francisco during the last glacial maximum?





13)    Abyssal Fans occur at the mouths of submarine canyons. True or False?




14)    What are Turbidity Currents and what is their significance regarding sediment transport? (see page 98-99, Garrison)




15)    What is the Continental Rise?





16)    Why is the continental crust under the continental shelves faulted in down dropped blocks (see the left side of figure 4.8 page 93)?







17)    Define features of the Deep Ocean Basins (see pages 71-80, in Garrison text):


a.       Mid-Oceanic Ridges,

b.       Abyssal Plains,

c.       Aseismic Riges

d.       Seamounts

e.       Guyots,

f.        Ocean Trenches,

g.       Island Arc Volcanoes,

h.       Ocean Island Volcanoes

i.         Hydrothermal Vents


18)    Why are abyssal plains so flat? (see page 104-105)




19)    What happens to the bathymetry of the sea floor as you get closer to the Mid-Oceanic Ridges? (i.e. when you move from the abyssal plain to the Mid-Ocean Ridge – Compare Figures 4.22b and 4.27)





20)    What are the distinctions between Seamounts and Guyots.




21)    Why are Guyots flat?



22)    What is a fringing reef, barrier reef, and atoll?  How do these form?




23)    What is an Oceanic Trench? (e.g. subduction zone)




24)    In what type of tectonic setting are Island Arc Volcanoes formed?



25)    Be able to name at least two famous chains of Island Arc volcanoes in the world, and also be able to locate any of these in the World Ocean.




26)    How are Ocean Island Volcanoes formed (e.g. Hawaii)?



27)    Be able to name at least two famous chains of Ocean Island Volcanoes, and also be able to locate any of these in the World Ocean.