Midterm 1 Flashcards
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The first major oceanographic expedition that carried out a variety of oceanographic measurements across several oceans was
C. Wyville Thompson’s Challenger Expedition
The primary variable responsible for the the physical stratification of the ocean is:
Density
The concept of Earth as a System includes several ‘spheres’ that are inter-connected and affect each other at different time- and spatial scales. Which of the following ‘spheres’ include organisms responsible for photosynthesis in the ocean:
Biosphere
The average elevation of the continental crust is much higher than the oceanic crust because:
The density of the oceanic crust is greater than the density of the continental crust
Which of the following tools have been used to measure bathymetry?
Ship-based multibeam echosounders,
lead lines dropped off the side of ships, and altimetry of sea surface height from satellites
Which of the following is an example of stable stratification in an Earth system?
Dense oceanic crust sinks under less dense continental crust
Based on the principle of Isostasy, the vertical distribution of Earth’s crust (i.e. continental and oceanic lithosphere) relative to the underlying mantle depends on:
thickness and density
The Pacific Northwest margin is considered an active convergent margin for all the reasons listed here
Earthquakes are common along the region between the Juan de Fuca Plate and the North American Plate, A chain of volcanoes is located north-to-south along the North American Plate, and The age of the Juan de Fuca plate is rather young (10 million years) even though the Pacific Ocean has existed for a very, very long time (200 million years).
The idea of continental drift used evidence from the fitting shapes of continents and commonalities of fossils and rocks across ocean basins to explain the mechanisms and rates of plate tectonics
False
An understanding and visualization of the global pattern of earthquakes was achieved because of:
A. Development of accurate and sensitive seismographs, and Expansion of seismographic stations across different contiental and oceanic regions of the planet
A good example of the MATURE stage of the Wilson Cycle is: (select the best choice)
Atlantic Ocean
Because of water’s unique properties, the surface of the ocean can be cooled (i.e. heat being removed) by which of these processes: (choose best answer)
Direct transfer of heat to a colder atmosphere above, Transfer of moisture to a drier atmosphere above due to evaporation
What are the four most abundant dissolved ions that make up seawater?
Chloride, Sodium, Sulfate, Magnesium
What is the best explanation for the contrasts between dissolved solutes in river and ocean water?
A) Dissolved elements coming into the ocean from rivers are removed from ocean in different ways and at different rates
B) The much higher concentration of dissolved solutes in the ocean reflect the rapid evaporation of water relative to the residence time of major salts in seawater
C) There are additional sources of dissolved solutes into the ocean besides rivers (e.g., hydrothermal fluids, dust
The concept of residence time (RT) for a dissolved ion brought into the ocean by rivers can be most easily visualized in comparison to the residence time of river water using the following equation:
RT(any ion) = RT(river water) x Concentration (ion in ocean)/Concentration (ion in river)
Given that
RT(river water) = 35,000 years
Concentration of SiO2 in river = 13.1 mg/liter
Concentration of SiO2 in ocean = 3.0 mg/liter
Which of the following is the most correct statement
The residence time of SiO2 in the ocean is considerably less (about 8,000 years) compared to river water
