OCE Midterm Ch 2

Which of the following is the main reason that Earth has a magnetic field?

Rotation of the liquid iron-nickel outer core generates a magnetic field.

Which of the following is characteristic of oceanic-oceanic convergent plate boundaries?

Volcanic island arcs

What was the main reason scientists objected to Alfred Wegener's idea of continental drift?

Wegener's proposed mechanism for movement was thought to be against the laws of physics.

All continents fit together with the least number of overlaps and gaps when the continents are matched along:

contours at around 2000 meters in depth

If ocean crust forms at a rate of 10 centimeters per year, how much ocean crust can be created in 20 million years?

2000 kilometers

Which of the following statements best describes the relationship between Earth's geographic and magnetic poles?

The magnetic pole wobbles, but stays near the geographic pole

What do all plate boundaries have in common?

They are all zones of earthquakes

Of the following statements about sea floor magnetic anomalies, which is/are true?

They are oriented parallel to the mid-ocean ridge

The Mid-Atlantic Ridge is an example of a:

divergent boundary

Coral reef development includes the following stages:

fringing reef, barrier reef, atoll

Word Analysis:

hydrothermal vents, Panamerica

Moving from oceanic ridge to oceanic trench, the thickness of the lithosphere:

increases in proportion to the distance

The San Andreas Fault:

is a continental transform fault

Differences in height between continental crust and oceanic crust are explained by:

isostasy

Climate distribution on Earth is primarily controlled by:

latitude

Continental drift was confirmed through the study of the:

location of magnetic poles through geologic time

The Hawaiian Islands are located where the Pacific plate is:

moving over a hot spot

The seafloor magnetic pattern is best described as:

parallel to and symmetric about ocean ridges

All of the following provide evidence for continental drift except:

seafloor magnetic pattern

Deep ocean trenches are associated with:

subduction zones

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

the magnetic pattern on the seafloor

Oceans become deeper moving away from ridges due to:

thermal contraction of hot asthenosphere