Exam 2: The Way the Earth Works: Plate Tectonics

A geologist aboard a deep-sea research vessel has collected several drill cores of oceanic crust from the bottom of the ocean. The cores are collected in order from east to west along the bottom of the basin and are labeled A1, B1, C1, and D1, respectively. Core A1 has 2.88 meters (m) of clay and siliceous ooze covering 4.86 m of pillow basalt. Core B1 has 2.37 m of muddy, clay ooze covering 3.57 m of basalt. Core C1 has 2.11 m of clay and siliceous ooze above 3.2 m of basalt. Core D1 has 1.87 m of siliceous ooze over 2.54 m of basalt. Which core is closest to the mid-ocean ridge?

The primary difference between lithospheric and asthenospheric mantle that gives rise to numerous different patterns of physical behavior is

The mid-ocean ridges are elevated above the surrounding seafloor because

Consult the figure below. Abundant swamps led to the formation of coal during the Late Paleozoic in which of the following places?

Under the theory of plate tectonics, the plates themselves are

With increasing distance from a mid-ocean ridge, the age of oceanic crust

What happens when a continental plate meets an oceanic plate at a convergent boundary?

Are ocean floors uniformly flat? Explain why or why not.

In Wegener's evidence for continental drift, continents were proposed to fit together, such as the east coast of South America with the

At a subduction zone, the down-going (subducting) plate

The thickness of oceanic lithosphere is

Beneath a blanket of sediments, oceanic crust is primarily composed of

Plate tectonics theory is often referred to as the "unifying" theory in geology. Explain why plate tectonics is such an important theory to the study of Earth.

Slab pull occurs because subducting slabs are __________ and therefore __________ than surrounding asthenosphere.

Which of these parts of the deep-ocean floor is flat and nearly featureless?

The image below shows a view of a typical segmented mid-ocean ridge. Which letter below marks the location of the active transform fault?

Discuss why transform boundaries are found in conjunction with divergent boundaries.

Subduction zones occur at

Wegener's idea of continental drift was rejected by American geologists because

Seafloor spreading is driven by volcanic activity