Ocean Floor - Mid-Ocean Ridge

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What is the characteristic of the sediments in the profundal zone?

Coarse particles lacking a benthic macroflora

Fine particles largely made up of material produced within the lake (correct)

Dark colored sediments with abundant benthic macroflora

Light particles with high organic matter production

Why do old shells of gastropods and pelecypods accumulate in the sublittoral zone?

Due to the high oxygen levels in the sublittoral zone

Because they prefer the warmer temperatures in the sublittoral zone

Because the sublittoral zone serves as a cemetery for some littoral species (correct)

Because they are actively transported from the littoral zone

What effect can onshore winds have on coastal operations?

Extend 5 to 10 nautical miles offshore at speeds of 4 to 6 knots

Cause wind shear, heavy rain, hail, and high winds

Create taller waves and lift moist sea air over coastal hills (correct)

Reduce visibility and carry smoke, fog, and dust offshore

What does the benthos in a lake reveal about the conditions in the hypolimnetic water?

The nature of the lake Signup and view all the answers

What is a common danger associated with terrain-forced thunderstorms?

Hurting communications and airborne operations Signup and view all the answers

What geological feature is formed at a spreading center where two plates are drifting apart?

Mid-Ocean Ridge Signup and view all the answers

What kind of volcanic feature is likely to form over hot spots in the ocean floor?

Seamount Signup and view all the answers

At what rate are the plates spreading at the mid-ocean ridge, leading to new oceanic crust formation?

2.5 centimeters a year Signup and view all the answers

What geological feature is formed when the peak of a seamount erodes and becomes a flat surface?

Guyot Signup and view all the answers

What type of feature is likely to form when the peak of a seamount pierces the ocean surface?

Volcanic Island Signup and view all the answers

What is the main concern for boats, submarines, swimmers, and torpedoes approaching shipwrecks?

Visibility due to bioluminescent organisms Signup and view all the answers

How does the presence of bioluminescent organisms affect the visibility of a ship's wake?

It can make the ship's wake visible up to 6 nautical miles Signup and view all the answers

Which factor can disturb the depth of the thermocline in the water?

Tides or currents Signup and view all the answers

What characteristic differentiates the marine life in littoral areas from that in near-surface open ocean?

Increased presence of marine life Signup and view all the answers

Which of the following can cause coastal currents to change rapidly, rendering current charts ineffective?

Wind, tides, and sea surface slope Signup and view all the answers

What type of animals thrive in the continental shelf regions?

Benthic species Signup and view all the answers

Which zone begins at the continental shelf break and is usually up to 20 km wide?

Profundal zone Signup and view all the answers

What is the primary source of nourishment for microscopic plants and animals in the ocean?

River and wave-washed sediment Signup and view all the answers

Which of the following is NOT a characteristic of land-fast ice?

It increases the salinity of water Signup and view all the answers

Where do lake benthos typically reside?

On the lake bottom Signup and view all the answers

How does wind shear affect Navy operations?

It can cause turbulence, making missions dangerous for aircraft and helicopters. Signup and view all the answers

What happens when a river meets the ocean in terms of water density?

Fresh river water flows into salty ocean water, creating density differences. Signup and view all the answers

How can reefs, bars, and channels impact the underwater environment?

Bars and channels can alter the shape of the ocean bottom, posing challenges for submarines and divers. Signup and view all the answers

What is a potential danger associated with winds creating high waves at sea?

The winds can block inland targets as waves become higher. Signup and view all the answers

How do differences in wind patterns above and around mountains affect the Navy's operations?

It creates wind shear that can make helicopter landings unstable. Signup and view all the answers