Plate Motion Evidence Practice Test

Two maps show evidence that builds up over long time periods (millions of years). Plates move slowly and continuously.

Map A: Seafloor age bands are symmetric on both sides of a long, straight ridge. The youngest crust is along the ridge, and the crust gets older in stripes moving away from it. Small arrows point away from the ridge on both sides.

Map B: Seafloor ages are mixed without clear bands. Earthquakes are scattered across the whole area with no main line.

Which region shows clearer evidence of ongoing plate motion over time?

Map 6 shows a coastline with a long, straight line on land labeled “fault trace.” Earthquake dots form a narrow band that follows the fault trace for hundreds of kilometers. There is no continuous line of volcano triangles along the fault trace. Two arrows on opposite sides of the fault point in opposite directions, parallel to the fault line. This pattern reflects movement over time because plates move slowly and continuously.

Which explanation fits the pattern shown?