Ocean Floor & Geology
📋 What it is
The seafloor has mountains, trenches and volcanoes — mapped using sound (sonar) since we can’t see it.
🗣️ Coach says
The ocean floor is as dramatic as any land: towering underwater mountain ranges, deep trenches (the deepest deeper than Everest is tall), and volcanic vents. Since light can’t reach it, scientists map it with SONAR — sending sound pulses and timing the echoes. It’s a hidden landscape shaped by plate tectonics.
🧠 Memory hook
Seafloor = mountains + trenches + volcanoes (deeper than Everest is tall). Mapped by SONAR (sound echoes).
😂 Giggle
Why are jellyfish terrible at making decisions?
They have no brains!
😲 Whoa!
The deepest ocean trench (the Mariana Trench) is so deep that if you dropped Mount Everest into it, the peak would still be over 2 km underwater.
✅ Quick check: How do scientists map the seafloor when they can’t see it?
Say your answer out loud first — then reveal.
With sonar — sending sound pulses down and timing the echoes; longer delays mean deeper water.
Sonar uses sound echoes to map depth.
🧪 Try it! (2 minutes)
Clap in a big room and time the echo — that’s the idea behind sonar mapping the seafloor.