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Place 03 · The Galápagos · Chapter 6 of 7
Islands on a Conveyor Belt
The Galápagos are drifting toward South America about as fast as your fingernails grow, and the oldest ones are already sinking.
About 15 minutes · 1 video · 1 3D model · 2 quick activities
Start here
The islands have birthdays, and they run east to west
Travel from Española in the east to Fernandina in the west and you go from islands about 3 to 4 million years old to one less than 700,000 years old that is still erupting. That is no coincidence. A fixed plume of hot rock under the seafloor keeps punching up new volcanoes, and the Nazca Plate keeps carrying them away, roughly east, about 5 cm a year.
Watch this
See it move
EVNautilus — Hot Spot Island Chain Formation. A short teaching animation from the Nautilus exploration team; it uses Hawaii, but the Galápagos run exactly the same machine.
While you watch, look for
- Where each new volcano forms, and whether that spot moves
- What happens to an island once the plate has carried it away from the hot spot
- Something you did not expect. Hold onto it.
The short version
Three things going on here
The plume
A blowtorch that stays put
Deep under the Galápagos, a column of unusually hot rock called a mantle plume rises through the mantle. Near the top it partly melts, and the magma breaks through the seafloor as volcanoes. Geologists call the place where it comes up a hot spot, and it stays put while the plate slides over it.
The belt
Oldest east, youngest west
The Nazca Plate, one of the moving slabs of Earth’s rocky shell, slides over the hot spot at about 5 cm a year, heading roughly east. Each volcano is born in the west over the plume, then rides away from its magma and goes quiet. So San Cristóbal and Española, about 3 to 4 million years old, sit in the east, while Fernandina, the youngest, still erupts in the west, as recently as 2024.
The sinking
Islands that drowned
Carried away from the hot spot, an island cools, sinks and is ground down by waves until it becomes a seamount, a mountain under the sea. East of today’s islands, scientists have found drowned Galápagos islands 5 to 9 million years old, older than any island you can visit. Hawaii runs the same machine on the Pacific Plate, and its trail of seamounts goes back about 80 million years.
Photos: Tomáš Malík, Diego F. Parra, Ben Phillips / Pexels
Play with it
Fly over the youngest island
This 3D model is Fernandina, the westernmost Galápagos island, sitting almost on top of the hot spot. Drag to spin it and scroll to zoom: find the summit crater (the caldera) and follow the slopes down to the sea.
3D model: “Fernandina Island” by MassiGr. on Sketchfab.
Two questions to answer while you are in there
- What shape is Fernandina: a sharp cone, or a broad dome with a crater on top? What does that tell you about how it was built?
- Española is 3 to 4 million years old and low and flat. What will waves and sinking do to Fernandina once the plate carries it east?
Try it yourself
Check yourself
Try it
Older or Younger?
Eight quick calls: read the clue, decide which way the belt points.
Try it · interactive
Hotspot Conveyor
Slide time from 5 million years ago to today and watch the Nazca Plate carry each new volcano away from a fixed hot spot, where it ages, erodes and sinks into a seamount.
Open the Hotspot Conveyor in its own window (opens in a new tab).
Words you will hear
Four terms, that is all
Hot spot
Fixed place where magma breaks through a plate
Mantle plume
Column of hot rock rising from deep Earth
Tectonic plate
A moving slab of Earth's rocky shell
Seamount
An underwater mountain, often a drowned volcano
Check your understanding
Practice the whole chapter
Everything in this chapter, in eight quick questions. Retry as often as you like. Read the feedback on every answer, right or wrong, because that is where the learning is.
Practice
Practice: Islands on a Conveyor Belt
Eight questions covering the video, the three cards, the four terms and the interactive above.
If you want more
Go deeper
- Webb 4.9 — Seamounts and Hot Spots — LibreTexts · 8 minutes
- Webb 4.4 — Plates and Plate Motions — LibreTexts · 10 minutes
- USGS This Dynamic Earth — Hotspots: Mantle Thermal Plumes — U.S. Geological Survey · 6 minutes
Photo credits (Pexels): Lloyd Douglas, Tomáš Malík, Diego F. Parra, Ben Phillips.