OCE1001 Test 1
4.6 billion years old
Earth is about
plant photosynthesis provides oxygen that is critical for aerobic respiration
Earth's current atmosphere supports animal life because __________.
A compass points toward the North Pole during normal polarity and to the South Pole during reverse polarity.
How are normal polarity and reverse polarity of Earth's magnetic field different
A record of Earth's magnetic field is recorded in oceanic rocks, which show a clear pattern of changes in Earth's magnetic polarity
In general, what is our best evidence that the orientation of Earth's magnetic field has changed over time
theory
In science, a well-substantiated explanation of some aspect of the natural world
- a sandy beach -at the base of the continental slope -the abyssal plains
In which of the following environments would you expect lithogenous sediment to be the dominant sediment type? Choose all that apply.
Asthenosphere
Isostatic adjustments are the result of the buoyancy of Earth's lithosphere as it floats on the ________ below which is denser and plastic like
Baffin Land
It is believed that Eric the Red may have discovered this area.
all of the above
Marine sediments provide valuable clues about which of the following Earth history events? Choose all that apply.
continental volcanic arcs, volcanic island arcs
Melt from the subducting plate rises to the surface, erupts through the crust on the overriding plate and forms ______________ on continents, or __________ in the ocean.
in the same direction as the plates are spreading
The direction of motion along a seafloor transform fault is
Erathso
The first person we are aware of who determined the circumference of the Earth using trigonometry and the angle of sunlight at Alexandria, Egypt, was:
Atlantic, Pacific, Indian, Southern, and Arctic Oceans
The four principal ocean basins (plus an additional ocean) on Earth are the
gas hydrate
The main energy resources associated with marine sediments are petroleum and ________.
- the Pacific Ring of Fire narrow or no continental shelves - subduction zones and associated faults - very deep ocean water depths - volcanic arcs and active continental margins
The majority of ocean trenches are associated with ___________. Choose all that apply.
the mid-ocean ridge
The majority of ocean trenches are associated with all of the above except
bathymetry
The measurement of ocean depth and the charting of seafloor topography is called __________.
Pytheas
The method of determining latitude in the Northern Hemisphere by measuring the angle between an observer's line of site to the North Star and line of site to the northern horizon was developed by:
abyssal plain far from a continent.
The most likely place to find abundant manganese nodules is on the:
-Continental crust is thicker than oceanic crust. -Continental crust floats higher on the mantle than oceanic crust. -Continental crust is mainly composed of granite, whereas oceanic crust is mainly composed of basalt
Which statement(s) below correctly describe differences between oceanic and continental crust?
divergent
Which type of plate boundary is most closely associated with the formation of new ocean floor?
vasco nunez de balboa
Who is credited with being the first European to see the Pacific Ocean?
Eratosthenes
Who is credited with being the first person to accurately determine Earth's circumference?
Juan Sebastian Del Cano
Who left Spain in September 1519 and became the first person to complete a circumnavigation of the globe when he returned to Spain three years later?
Submarine canyons, turbidity currents
______________ are deep valleys at passive continental boundaries. They are likely carved out by __________, which occur when sediment-laden water rapidly moves down slope.
deep sea trenches
Active continental margins are characterized by which of the following?
Arctic
Based on definition, it is more appropriate to consider which ocean as a sea?
Broad continental shelves
Characteristics of passive continental margins include which of the following?
observation
Collection of scientific facts through observation
water vapor released from volcanic outgassing
Current scientific knowledge indicates that the most likely origin of most of Earth's oceans was due to ________.
outgassing
Earth's second atmosphere formed from ________.
basalt
Oceanic crust is primarily
mid-ocean ridges
Oceanic crust spreads at ____________ , creating new crust and slowly enlarging the ocean basin.
- a wide continental shelf - a continental rise
Of the following items, which is/are associated with a passive continental margin? Choose all that apply
- manganese nodules - coatings of metal sulfides near black smokers
Of the following sediments, which one(s) is/are considered hydrogenous? Choose all that apply.
- Multibeam surveys from ships produce very detailed maps of the sea floor. - Measurements of sea surface elevation by satellites are used to produce maps of the sea floor. - Only about 20% of the sea floor has been accurately mapped in detail.
Of the following statements about mapping the ocean floor, which is/are true? Choose all that apply.
-The asthenosphere is a highly viscous layer located beneath the lithosphere. -The asthenosphere is very hot and contains areas of partially molten rock.
Of the following statements about the asthenosphere, which is/are true? Choose all that apply
-Petroleum -Gas hydrates
Of the following, which energy resource(s) can be extracted from marine sediments? Choose all that apply.
can form ozone and block some UV radiation.
One of the reasons that free oxygen in our atmosphere is important to the development and maintenance of life on Earth is because oxygen:
Shape, position
Our world ocean can be divided into four principal oceans plus an additional ocean, based on the ________ of the ocean basins and the ________ of the continents.
Continental rifting and continued sea floor spreading
Passive margins are usually produced over geologic time by which of the following?
the shape of the ocean surface reflects large features on the seafloor
Satellites are used to map the ocean floor because ________.
Ring of fire
Subduction zones surrounding the Pacific Ocean give rise to volcanoes. This area surrounding the Pacific Ocean is called the _________.
differing densities of the elements that make up the Earth
The separation of the Earth into layers while it was molten was the result of the
geographical
The study of the structure of the sea floor and how the sea floor has changed through time is an example of ________ oceanography.
Earth's magnetic field switches polarity at irregular time intervals
Which of the following statements about Earth's magnetic field is most accurate?
They record the timing and severity of some global extinction events.
Which of the following statements about marine sediments is correct?
-Aluminum -Silica
What element(s) are found in high concentrations in continental crust?
-Magnesium -Iron
What element(s) are found in high concentrations in oceanic crust
iceland
What is the first new land conquered by the vikings
Vinland (newfoundland)
What is the land discovered by Leif Erikson
- trench formation at convergent boundaries - large fluctuations in sea level over geologic time - major climate changes, such as ice ages - tectonic activity produced by offshore faults
What processes influence the shape and features of continental shelves? Choose all that apply
Greenland
When Eric the Red was banished from Iceland, he discovered this land, where he later started a colony.
thermal energy that was converted from the gravitational energy of the original nebula collapse
Where did the energy of the Sun come from originally
on both sides of the mid-ocean ridge
Where would you expect to see alternating bands of rock with different magnetic polarities
- basalt volcanism and pillow lavas - a central rift valley - volcanoes - hydrothermal vents
Which of the following feature(s) is/are associated with the mid-ocean ridge? Choose all that apply
suspension settling
Which of the following is the predominant process that forms the thick blanket of sediment on abyssal plains the deep-ocean floor?
Petroleum
Which of the following resources found in ocean sediments has the greatest economic value?
hypothesis
a tentative, testable statement about the natural world
testing
development of observations, experiments, and models to test
1. Calcareous ooze 2. abyssal clay 3. siliceous ooze
order types of marine sediment in order of abundance
microscopic organisms
the ancient remains of which of the following, buried before they could decompose, are the source of today's petroleum deposits?