Geology quiz 4

What is the percentage of dissolved salt in seawater?

3.5%

Approximately what percentage of Earth's surface is covered with water?

70%

Using the figure below, which of the following lists correctly identifies the various seafloor landform.

A = continental shelf, B = continental slope, D = continental rise, G = abyssal plain, C = mid-ocean ridge, F = trench, and E = volcanic arc

Why is the surface salinity in the tropics so much higher than that of the equator or high latitudes?

There is a higher evaporation rate and a lower rate of precipitation in the tropics

You are running a sonar survey to map the bathymetry of an ocean basin. Using the following continuous sonar data giving the depth of the seafloor, what feature have you just discovered?

a mid-ocean ridge

Which type of coastline would most likely contain estuaries or fjords?

a submergent coastline

The form and topography (depth profile) of the ocean floor is termed ______

bathymetry

Why is a spring tide so much higher than a normal high tide?

because the sun is aligned with the moon

In the figure below, which letters represent the crest and trough?

c and d

The density of seawater increases with ________ temperature and ________ salinity.

decreasing; increasing

Compared with the continental crust, the oceanic crust is ______

denser

When the sea level rises, an ocean may invade a river valley, producing a nearshore body of water of mixed and variable salinity termed a(n) ________.

estuary

Rip currents_____ the shoreline.

flow directly away from

Longshore currents_____ the shoreline.

flow parallel

Because of wave refraction, erosion along an irregular coastline is______

greatest along headlands

Ephemeral streams ________

have flowing water either episodically or during a portion of the year

High tide will be ________ during a full moon than normally.

higher

Mid-ocean ridges (MORs), which are the sites of new oceanic crust formation, are linear mountain chains that run along divergent plate boundaries. Why does an MOR sit up higher than the surrounding oceanic crust?

hot materials are less dense and expand, thus the new crust will sit higher than the surrounding crust

The sea surface salinity is ________ at the mouth of the Amazon River and ________ in the Dead sea.

low; high

Bioturbation is the_______

mixing of sediment by burrowing organisms

Saline ocean water is ________ dense than fresh water and provides ________ buoyancy to objects floating in it.

more; more

At the equatorial ocean basins, the sea surface temperatures may reach 25°C or greater. What is the range of temperatures for the seafloor, approximately 4-5 km below?

near freezing

Runoff is NOT commonly derived from ________.

ocean currents

A wave will disturb the water to a depth equal to______

one-half of its wavelength

Waves_______

refract so as to impact the shore in a nearly parallel manner

The U-shaped valleys in Kenai Fjords national park in Alaska were created during an_______

regression

If sea level continues to rise and covers the city of Miami, the Florida coast will become a(n) ________.

submergent coast

Barrier islands are constantly moving in the direction of______

the longshore drift

Geological evidence suggests that many millions of years ago, the Amazon basin drained toward the west rather than the east. What caused this drainage reversal?

the rise of the Andes mountains

Thermohaline circulation carries ________ water from the poles to the equator, where the water becomes ____.

warm; cold