Oceanography Midterm 2

Ocean circulation patterns

All of the following provide evidence for the early continental drift model except:

Deep-sea trenches

Passive continental margins are characterized by all of the following except:

4-5 billions years

Radioactive isotopes can sometimes be used to determine the:

Solids

S (secondary) waves would travel through the following layers:

Chemical weathering, dissolved materials in river water, erosion of the continents & volcanic activity

Salts in the ocean are derived from the following sources:

the magnetic pattern on the seafloor

Scientists (Vine and Matthews) determined that new ocean floor was being produced at ocean ridges by examining:

The patterns of S and P waves

Scientists discovered that the outer core of Earth is liquid by using:

70%

Seawater covers approximately what percent of Earth's surface?

The Universe is expanding

The "red shift" of starts in our Universe is the best evidence for what?

Moving over a mantle hot spot

The Hawaiian Island are located where the Pacific plate it:

A new linear sea

The Red Sea is an example of:

Antarctic

Which main ocean is the largest and the deepest?

Upwarping & Rift Valley formation

Which of the following is associated with early stages of continental rifting?

Outer core

Which part of Earth's layers is liquid?

fringing coral reef

Which stage in the development of coral reefs is most mature?

trench

Which type of geologic feature(s) would be most-associated with an active oceanic-continental margin?

passive margin

Which type of margin would be most associated with submarine canyons and turbidity currents?

Distance from the Sun

Which unique condition appear to cause Earth to have oceans?

Plants lived near the poles, but have drifted to current locations

Fossils of ancient polar plants are currently found near the equator because the:

Radioactivity in the mantle

Heat for convection within Earth comes primarily from:

Indirect observation

Most of what we know about our solar systems (outside of planet Earth) is through:

Crust, Lithosphere, Asthenosphere & Outer core

P (primary) waves would travel through the following layers:

Transform

Volcanism is not associated with which plate tectonic boundary?

turbidity current

A sediment-laden current that flows off the continental slop is called a:

25%

After two half-lives of a radioactive material, how much of the original radioactive material is left?

4 billions years

Approximately how old are Earth's oceans?

Atlantic

As a result of modern plate tectonics, which major ocean is getting larger?

Mountain building, volcanism, & earthquakes

As an oceanic plate converges with a continental plate, the following is likely to occur:

Island arc formation & volcanism

As an oceanic plate converges with an oceanic plate, the following is likely to occur:

age of the seafloor

Confirmation of seafloor spreading was supported by the:

less dense than ocean crust and it is generally thicker

Continents "float" higher above the mantle than the ocean basins because continental crust is:

Isostasy

Differences in height between continental crust and oceanic crust (as they "float" on the athenosphere) are best explained by:

Very toxic compared to our modern atmosphere

Earth's early atmosphere with respect to it chemical nature was:

Convergent, divergent & transform

Earthquakes are associated with which boundaries?

New oceanic crust must be created at the mid-ocean ridge & old oceanic crust is being recycled at the continental margins

If the age of the seafloor increases from the mid-ocean ridge toward the continents, what must be true?

How much salt (kg/cubic meter) is in the oceans, input of salts (rivers), outputs of salts (shells and minerals) & volume of water in the oceans

In order to develop a simple mass balance of salt content in the oceans over geologic time, which items below would you need to know?

Asthenosphere

In the outermost 700 km of Earth's structure, which part is capable of flow?

Galaxy, solar system & planet

The correct arrangement of astronomical bodies from oldest to youngest is:

contain rift valleys

The crests of mid-ocean ridges:

Outgassing & volcanism

The development of water on Earth primarily was the result of:

Convergent boundary (Continent-continent)

The formation of the Himalaya Mountains, in Asia, is the result of:

Sound waves

The indirect method that is most frequently used to investigate sediment and rock layers of the seafloor is:

They are buried from sediment derived from the passive margin

The main reason abyssal hills or seamounts are not as common on passive margins is:

A reasonable driving mechanism

The major weakness of the early continental drift model was:

divergent boundary

The mid-ocean ridge is an example of a:

All bodies in the solar system formed from an enormous gas cloud

The nebular hypothesis suggests that:

Showing the seafloor spreading was occurring & supposing that convection currents in Earth's interior drive plate movements

The plate tectonics theory greatly improved on the continental drift model by:

Are offset and perpendicular to the main axis of the mid-ocean ridge

Transform boundaries associated with mid-ocean ridges:

Differing densities of the rock and mineral materials

The separation of the Earth into layers was the result of the:

Mid-ocean ridge

The youngest oceanic crust is located near the:

Convergent boundary (oceanic-oceanic)

Volcanic (or Island) Arcs are associated with which type of boundaries?