Passage 1: Volcanoes form where Earth's plates push together or pull apart. Deep underground, melted rock called magma collects in chambers. When pressure builds, magma rises and erupts as lava and ash. An eruption can quickly change the land by covering fields, carving new channels, and building steep cones. Although ash can damage towns at first, it also breaks down and adds minerals to the soil. Over time, plants return and the landscape shows new shapes made by the cooled lava.
Passage 2: Scientists watch volcanoes with seismometers, gas sensors, and cameras to warn people before eruptions. When lava flows, it can bury roads and homes, but it also creates new rock as it cools. Along ocean coasts, repeated eruptions may extend shorelines or even build small islands. After a big blast, rivers may be rerouted and hills may rise where none stood before. Communities often rebuild on safer ground, and maps are updated to show how the land has been reshaped by the volcano.
Which idea do both passages tell us about volcanoes?
Which idea do both passages tell us about volcanoes?