What type of plate boundary does the figure show?

Two neighboring plates slide horizontally past each other. What type of boundary separates them?

Which density comparison helps explain why the oceanic plate descends beneath the continental plate in the figure?

Which stress commonly produces a normal fault?

A reverse fault develops as rock blocks interact. Which stress most likely caused it?

After an earthquake, a road in Luzon is offset sideways across a break in the ground. Which fault motion best explains this observation?

A world map plots earthquake epicenters and active volcanoes. Which distribution best supports plate tectonics?

Which conclusion is supported by the magnetic stripe pattern in the figure?

How does the age of ocean-floor rock generally change with distance from a spreading center?

Glossopteris fossils occur on several southern continents now separated by oceans. Which explanation is best supported by this distribution?

Which feature of South America and Africa supported Wegener's continental-drift proposal?

What can the inclination of preserved magnetic alignment in ancient rocks help scientists estimate?

The formation of the Himalayas provides evidence of which plate interaction?

Why did Wegener's continental-drift proposal initially face strong scientific objections?

Which pair of scientists is associated with developing the seafloor-spreading hypothesis?

What does geodesy primarily study?

A permanent receiver in Luzon records its coordinates using signals from orbiting transmitters. Which technique can track its displacement over time?

All coordinates use the same reference frame. Which GNSS record best supports steady horizontal motion of a station attached to a tectonic plate?

Scientists compare the phases of radar signals from repeated satellite passes over the same area. Which technique detects ground deformation this way?

Widely separated radio telescopes compare signals from distant celestial sources to measure changes in their separation. Which technique is being used?

What did the original GRACE satellite pair primarily map?

Over one year, a tide gauge records a 6 mm rise while GNSS shows the land rose 2 mm. What was the sea-surface rise relative to the GNSS reference frame?

A ground station times light pulses reflected by special mirrors on an orbiting satellite. Which technique determines the distance?

An instrument aboard an orbiting spacecraft times pulses reflected from the ocean surface to determine its height. Which technique is this?

An instrument precisely tracks a freely falling test mass in a vacuum chamber. Which geodetic method uses this procedure?

Which combination of Earth materials makes up a tectonic plate?

Which letter marks Earth's liquid metallic layer?

Which description of the asthenosphere is scientifically accurate?

Why does a heated region of rock tend to rise when it can flow?

As an oceanic plate cools, which change favors its descent into Earth's interior?

Which pair supplies much of Earth's internal heat?

Which explanation describes ridge push?

Which mechanism usually contributes most to the motion of a plate with a long, cold descending edge?

What kind of heat transfer is represented by the circulating arrows in this figure?

If Earth eventually loses enough internal heat, what would generally be expected for its tectonic activity?

The offshore arrows represent Philippine Sea Plate motion relative to the Sunda Plate. Which process occurs along the Philippine Trench on the archipelago's eastern side?

Assuming constant motion, how far would a plate travel in 50 million years at 80 mm per year relative to another plate?

A constant-motion model predicts the Philippine islands' locations in 50 million years. Why might the actual arrangement differ?

GNSS stations on opposite sides of a Philippine island move toward each other. Which long-term change could this motion produce?

A plate moves at 80 mm/year for 10 million years, then 40 mm/year for 10 million years. How does its travel distance compare with a projection using 80 mm/year for all 20 million years?