Earthquake Measurement and Volcanic Activity
When an earthquake strikes, scientists need to locate exactly where it started. The focus (or hypocenter) is the underground point where rocks first break, while the epicenter is the spot directly above it on Earth's surface. Seismologists use triangulation - like GPS positioning - to pinpoint these locations.
Intensity measures how much damage an earthquake causes at specific locations, while magnitude measures the total energy released. Think of magnitude as the size of a stereo speaker and intensity as how loud it sounds from different distances.
Volcanism (also called magmatism) involves the expulsion of molten rock from volcanoes, studied by experts called volcanologists. Every volcano has a vent (the opening), crater (the bowl at the top), and sometimes a caldera (a massive crater formed when the volcano collapses).
The three main volcano types are: Composite volcanoes likeMayon−steepandexplosive, cinder cones likeTaal−smallandshort−lived, and shield volcanoes (broad and gentle, common in Hawaii). Each type erupts differently and creates distinct landscape features.
Quick Tip: Remember that composite volcanoes are the most dangerous because they can explosively shoot material several kilometers into the atmosphere!