Geology Chapter 15

________ are gently sloping areas on coastlines that consist mostly of sand. Tidal flats Beaches Lagoons Inlets

Beaches

Where do the deep ocean currents rise to the surface? the equator the North Pole the tropics the South Pole

the equator

If a beach is in an east-west orientation and the waves are approaching the shore from a southeasterly direction, in which direction will the longshore drift be? northern western southern eastern

western

Waves are created by ________. tides the Moon the crust wind

wind

Many rocky coasts occur along active margins; why is this? Active margins are associated with larger storms, which causes more erosion of sediment, leading to fewer beaches. Active margins are associated with volcanic activity, and volcanic rocks are very hard to erode; thus, there is not enough sediment produced. Active margins often experience repeated uplift, and thus the waves have not had sufficient time to erode the land surface down to sea level. Active margins tend to have far fewer streams that feed sediment to the oceans; thus, there is not enough sand to create beaches.

Active margins often experience repeated uplift, and thus the waves have not had sufficient time to erode the land surface down to sea level.

What would happen to the tides if the Sun and Moon are aligned? There would be no tides at all. There would be no low tides on Earth. High tide would be much larger. There would be only low tides on Earth.

High tide would be much larger.

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 a MOR sit up higher than the surrounding oceanic crust? Hot materials are less dense and shrink; thus, the new crust will sit higher than the surrounding crust. As the hot magma exits the MOR, it shoots up higher than the surrounding crust. Hot materials are less dense and expand; thus, the new crust will sit higher than the surrounding crust. Hot, geothermal waters cause the new crust to expand and sit higher than the surrounding crust.

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

The entire state of Florida is composed of fossiliferous limestone. What does this imply about Florida during the recent past? It was covered with caves. It was a submergent coast. It was an emergent coast. It was in the mountains.

It was a submergent coast.

Why do beaches become sediment-starved after dams are installed on rivers? Dams trap water, thus reducing the volume of water that enters the ocean and erodes away the coast to produce sediment. Rivers supply sediment to beaches; dams trap river sediment, and thus that sediment cannot make it to the beaches. The chemical composition of river water is changed when it flows through a dam; this alters the amount of chemical weathering that occurs along the coast. Dams are built using sediment covered in concrete; the sediment most often comes from nearby beaches.

Rivers supply sediment to beaches; dams trap river sediment, and thus that sediment cannot make it to the beaches.

________ provides the largest tide-generating force. The Sun The Moon Earth The ocean

The Moon

Why are waves larger during storms? The larger wind speeds create more shear. The storm increases the amount of upwelling. There is more water pulled in by the storm. The motion of the water becomes more elliptical.

The larger wind speeds create more shear.

How would the Coriolis effect affect the space station? The space station would curve to the right because it is above the Northern Hemisphere. The space station would curve to the left because it is above the Southern Hemisphere. The space station would not curve because it is above the equator and not affected. The space station would not be affected because it is not in Earth's atmosphere.

The space station would not be affected because it is not in Earth's atmosphere.

Major oceanic surface currents travel ________. parallel to the prevailing wind direction in a region in direct opposition to prevailing winds as a result of the Coriolis effect at an angle to prevailing winds as a result of the Coriolis effect at an angle to prevailing winds as a result of the Doppler effect

at an angle to prevailing winds as a result of the Coriolis effect

The form and topography (depth profile) of the ocean floor is termed ________. orogeny bathymetry allocthony aquitopography

bathymetry

Building a dam across a river can lead to ________ because sediment becomes trapped behind the dam. pollution beach nourishment reef bleaching beach erosion

beach erosion

What type of material would you expect to find on the continental slope? basalt and plankton shells carbonate-rich sediments and shells silicic-rich gravels and plant remains metamorphosed oceanic crust

carbonate-rich sediments and shells

Thermohaline circulation carries ________ water from the poles to the equator, where the water becomes ________. warm; cold cold; warm low density; more dense low density; more salty

cold; warm

Longshore current is the result of waves ________. coming in perpendicular to the shore coming into shore at an angle created during large storms retreating back to the ocean

coming into shore at an angle

The shallowest portions of an ocean found along the margins of continents are the ________. abyssal plains continental rises continental shelves continental slopes

continental shelves

The density of seawater increases with ________ temperature and ________ salinity. increasing; increasing decreasing; increasing increasing; decreasing decreasing; decreasing

decreasing; increasing

Compared with the continental crust, the oceanic crust is ________. denser less dense about the same density about half as dense

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) ________. atoll lagoon estuary jetty

estuary

When sea level rises and floods a glacially carved valley, the area is called a(n) ________. fjord wetland estuary reef

fjord

Longshore currents ________ the shoreline. flow directly toward flow directly away from flow parallel to are not affected by

flow parallel to

Because of wave refraction, erosion along an irregular coastline is ________. even along the length of the coast greatest along headlands greatest in bays the same as it would be along a regular coastline

greatest along headlands

High tide will be ________ when the Sun and Moon are aligned parallel to each other as opposed to normally (when they are not aligned parallel to each other). the same lower higher reversed

higher

The deepest segments of the ocean floor are found ________. along mid-ocean ridges in the geographic centers of abyssal plains in trenches associated with passive margins in trenches associated with subduction zones

in trenches associated with subduction zones

Along beaches, groins have ________. solved the problem of beach drift increased erosion rates immediately up current from the groin increased erosion rates immediately down current from the groin increased depositional rates immediately down current from the groin

increased erosion rates immediately down current from the groin

The sea surface salinity is ________ at the mouth of the Amazon River and ________ in the Great Salt Lake, Utah. low; low high; low low; high high; high

low; high

A wave will disturb the water to a depth equal to ________. its wavelength its surface amplitude the bottom of the seafloor one-half of its wavelength

one-half of its wavelength

Coastal landforms are constantly changing because the ________. sand is constantly moving tides are getting stronger sand is moved by developers storms are getting stronger

sand is constantly moving

As a wave passes through the open ocean, the water molecules move ________. horizontally diagonally in a circular path straight up and down

straight up and down

Which type of coastline would most likely contain estuaries or fjords? subductive emergent submergent divergent

submergent

If sea level continues to rise and covers the city of Miami, the Florida coast will become a(n) ________. emergent coast submergent coast continental slope abyssal plain

submergent coast

Barrier islands are constantly moving in the direction of ________. the longshore drift the high tide down welling the Coriolis effect

the longshore drift

Which of the following would be an area of the ocean with the LEAST dense water? the mouth of the Amazon River off the coast of Africa the middle of the Pacific Ocean off the coast of Madagascar

the middle of the Pacific Ocean

Which is the larger of the two tidal bulges? the one farthest from the Sun the one farthest from the Moon the one closest to the Sun the one closest to the Moon

the one closest to the Moon

The Coriolis effect causes the apparent deflection of currents due to ________. changes in wind speed the rotation of Earth changes in ocean currents the location of the Moon

the rotation of Earth

What prevents each spot on Earth from experiencing two high tides and two low tides a day? the shape of the seafloor and coastline the shape of the tidal bulges the position of the Moon relative to Earth the position of the Sun relative to the Moon

the shape of the seafloor and coastline

Compared with the continental lithosphere, the oceanic lithosphere is ________. thicker thinner approximately the same thickness exactly five times thinner

thinner

The castle on the island of Mont Saint-Michel, France, can be accessed ________ a day during ________ tide. twice; high once; low twice; low once; high

twice; low