oceanography chapter 3
c
Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern. a. Abyssal hill b. Tablemount c. Submarine canyon d. Abyssal plain e. Seamount
d
New lithosphere is produced in association with: a. fracture zones b. deep-sea trenches c. hydrothermal vents d. oceanic ridges e. transform faults.
a
Oceanic ridges and rises result from seafloor spreading along ________. a. divergent plate boundaries b. convergent plate boundaries c. transform plate boundaries d. convergent and transform plate boundaries e. convergent and divergent plate boundaries
a,b
Of the following items, which is/are associated with a passive continental margin? Choose all that apply. a. a wide continental shelf b. a continental rise c. volcanic eruptions and pillow lavas d. a deep-ocean trench e. an abundance of earthquake activity
a,b,d,e
Of the following techniques, which one(s) can be used to map the sea floor? Choose all that apply. a. sending sound through water (sonar) b. recording many depths using a long cable c. measuring seawater clarity d. direct visitation of the sea floor e. using satellites to measure the sea surface
e
Older lithosphere is destroyed in association with: a. mid-ocean ridges b. fracture zones c. hydrothermal vents d. spreading centers e. deep-sea trenches
c
Trenches are typically associated with a. transform continental margins b. passive continental margins c. convergent continental margins d. abyssal hills e. fracture zones
d
Volcanic peaks that are below sea level but rise more than 1 kilometer above the deep-ocean floor and have a pointy top like an upside-down ice cream cone are called ________. a. guyots b. nemataths c. seaknolls d. seamounts e. islands
d
What is a linear sea floor feature that is seismically inactive, occurs beyond offset mid-ocean ridge segments, and the relative movement between two points on either side of the feature is in the same direction? a. Guyots b. Seaknolls c. Transform fault d. Fracture zone e. Nemataths
b
Where a mid-ocean ridge is offset, the linear feature connecting and between the crests of the ridge segments is called a a. central rift valley b. transform fault c. fracture zone d. seismic fissure e. hydrothermal vent
d
Where are the deepest portions of the world's oceans found? a. At submarine canyons b. At the intraplate abyssal plains c. At transform plate boundaries d. At convergent plate boundaries e. At divergent plate boundaries
e
Where does the deep-ocean basin begin along a passive continental margin? a. Continental shelf b. Abyssal plain c. Shoreline d. Continental rise e. Continental slope
b
Which of the following features is related to transform faults along mid-ocean ridges? a. Continental shelf b. Fracture zone c. Continental slope d. Submarine canyon e. Continental rise
b
Which of the following is the predominant process that forms the metallic minerals in and around black smokers? a. Undersea streams b. Precipitation c. Melting icebergs d. Suspension settling e. Turbidity currents
d
Which part of Earth's cumulative hypsographic curve includes linear scars in the ocean floor, caused by the collision of two plates along convergent plate margins? a. The gentle slope above sea level b. The long and flat part below sea level c. The shallowest slope below sea level d. The steep deepest part below sea level e. The steep segment above sea level
c
Which part of Earth's cumulative hypsographic curve includes the continental shelves of passive margins? a. The gentle slope above sea level b. The long and flat part below sea level c. The shallowest slope below sea level d. The steep deepest part below sea level e. The steep segment above sea level
b
With respect to mid-ocean ridges, transform faults are: a. associated with hydrothermal vents b. perpendicular to the ridge axis c. located in submarine canyons d. parallel to the rift valley.
e
Worldwide, scientists estimate that there are about 125,000 known seamounts, many of which originated at ________ centers. a. sedimentary b. metamorphic c. seismic d. erosional e. volcanic
a
Active continental margins are characterized by which of the following? a. Deep-sea trenches b. Sparse earthquake activity c. Broad continental shelves d. No sediment accumulation e. Shallow coastal waters
e
An oceanographic vessel is mapping a section of the ocean floor stretching for tens of miles in all directions. The seafloor is extremely flat, with a slope of less than one degree, and the water depth is about 4,500 meters. The area being mapped is most likely a(n) __________. a. continental slope b. continental border land c. continental rise d. continental shelf e. abyssal plain
e
Characteristics of passive continental margins include which of the following a. chains of islands b. Deep-sea trenches c. Thin sediment accumulation d. Volcanic and earthquake activity e. Broad continental shelves
b
Directly seaward of the continental shelf is a more steeply sloping region called the: a. continental rise b. continental slope d. mid-ocean ridge e. abyssal plain.trench.
b
In comparison with other ocean basins, major sedimentary features such as continental rises and abyssal plains are relatively rare in the Pacific. The primary reason for their scarcity in the Pacific is that __________. a. turbidity currents are rare in the Pacific, so little sediment is carried down the continental slopes b. sediment is trapped within the trenches of the convergent plate boundaries ringing the Pacific c. rivers do not carry much sediment into the Pacific d. the Pacific Ocean is too large for those features to form e. the numerous volcanoes of the Pacific rim and islands prevent normal sedimentation
a
Most large ocean floor features owe their origins to _________. a. plate tectonic processes b. extreme pressure at depth c. biological activity d. ocean current activity e. erosion and weathering
a
Passive margins are usually produced over geologic time by which of the following? a. Continental rifting and continued sea floor spreading b. Subduction of oceanic crust and submarine volcanic activity c. The closing of an ancient sea to form a salt rich lake d. Transform faulting along a continental margin or a mid-ocean ridge e. Hot spot volcanism forming a chain of islands and seamounts
e
Sediments deposited by the process of suspension settling produce the majority of sediment found on a. the continental slope and rise b. the continental shelf c. submarine fans d. shallow islands in tropical seas e. abyssal plains
c
Segments of the oceanic ridge system that are gentler and less rugged in slope due to faster rates of seafloor spreading are called: a. deep-sea trenches b. fracture zones c. oceanic rises d. transform faults e. convergent plate boundaries
e
The two relatively flat areas on the hypsographic curve represent: a. continental slopes and deep-sea trenches b. continental mountains and mid-ocean ridges c. some interior continental areas/coastal plains and mid-ocean ridges d. continental mountains and abyssal plains e. some interior continental areas/coastal plains and abyssal plains on the ocean floor
b
Underwater avalanches of muddy water mixed with rocks and debris are: a. turbidite deposits b. turbidity currents c. white smokers d. deep sea fans e. graded bedding.