What is the main idea of the passage?

Multiple independent kinds of evidence combine to show that Earth's tectonic plates move and reshape the surface. (Each body paragraph adds a separate evidence line, and the conclusion emphasizes how they support one coherent account together.)

Why are mirrored magnetic bands especially useful evidence?

They record new crust forming at a ridge and moving outward on both sides over time. (Alternating directions record reversals, while symmetry across the ridge is the expected pattern if new seafloor spreads both ways.)

What does “coherent” mean in the final paragraph?

forming a consistent explanation whose parts fit together (The evidence comes from different sources but supports one account, so “coherent” means logically fitting together.)

Which evidence is described as measuring plate motion directly?

modern instruments (The final paragraph explicitly assigns direct measurement to modern instruments.)

The Plates Beneath Our Feet: Level 5 Reading Comprehension Questions

Continents appear fixed on a map, yet Earth's outer shell is divided into moving tectonic plates. Their motion is usually measured in centimeters per year, slow enough to escape daily notice but powerful over geological time. Plate tectonics became convincing not through one dramatic observation, but through several independent lines of evidence that fit together.

Coastlines first suggested a puzzle: some continental margins roughly match. The stronger evidence lies beyond shape. Matching fossils and rock belts occur on continents now separated by oceans, indicating that those lands were once joined. Records of ancient climates add another clue, including signs of past ice in regions that are warm today.

The ocean floor supplies a moving record. New crust forms along many mid-ocean ridges. As molten material cools, iron-bearing minerals align with Earth's magnetic field. Because the field has reversed many times, bands of crust preserve alternating magnetic directions. The broadly mirrored pattern on opposite sides of a ridge shows that seafloor has spread outward.

Modern instruments now measure plate motion directly. Earthquake and volcano patterns also cluster near many plate boundaries, where plates collide, separate, or slide past one another. No single clue explains every feature, and boundaries can be complex. Together, however, fossils, rocks, magnetic stripes, measurements, and seismic activity support one coherent account: Earth's surface continually changes as plates move.

Comprehension questions