The Hawaiian Hotspot is an ongoing volcanic process that started 70 million years ago and has created the Hawaiian Islands as the Pacific Plate moves over a fixed hotspot in the Earth's crust. A hotspot is a small area of unusually high heat flow that sustains volcanic activity even when not located at a plate boundary. As the Pacific Plate moved northwest over the Hawaiian Hotspot, a trail of volcanoes formed the Hawaiian-Emperor seamount chain, with the oldest islands located farthest from the current hotspot under Hawaii. Hawaii itself consists of 143 islands that range from 4 to 0.3 million years old and are still expanding due to ongoing volcanic eruptions from three active volcanoes.

1. The Hawaiian Hotspot
Question: How many times do you think Mt Everest can fit in Hawai’i?

2. 140 times

3. The Hawaiian Islands
• 8 Islands and 80 volcanoes in total
• Located in the Pacific Ocean & the middle of Pacific Plate
• 2,000 miles away from nearest plate boundary

4. What is a hotspot?
• A small area of the Earth’s crust with an unusually high heat flow
and is associated with volcanic activity
• Slow movement
• Inactivity in volcanoes occurs when
it moves away from the hotspot

5. Hotspots Map

6. Hotspot Diagram

7. The Hawaiian Hot Spot
•Ongoing process - started 70 million years ago
•Islands increase in age as you move north westwards from Hawai’i
•Hawaiian-Emperor Chain - Trail of volcanoes
•Sharp bend - Hotspot moved slightly southwards before becoming fixed

8. Major Physical Features
• Two types of volcanoes:
Shield (majority) Cinder Cone

9. Type of volcanic activity
• Hotspots have always confused scientists, because unlike the other
types of volcanic activity (such as convergent and divergent plate
boundaries), these volcanoes do not occur at plate margins.
• In 1963, J. Tuzo Wilson from Canada thought of ‘the hotspot
theory’. He realised that in certain locations around the world, such
as Hawaii, volcanism has been active for very long periods of time.
He reasoned that this could only happen if relatively small, long-
lasting, and exceptionally hot regions -- called hotspots -- existed
below the plates that would provide localized sources of high heat
energy (thermal plumes) to sustain the volcanoes.

10. Hotspot Example - Hawaii
• Underneath Hawaii, a “plume” lies at a fixed position under the Pacific
Plate. As the ocean floor moves over this hot spot, the upwelling lava
creates a steady succession of new volcanoes that migrate along with the
plate - a conveyor belt of volcanic islands, which we now call Hawaii.
• Hawaii is made up of 143 islands that range from 4 million years old to
300,000 years old.
• Hawaii is constantly expanding because of it’s volcanic activity and its
position on top of a hotspot. Within 19 years, lava flow has added 543
acres to Hawaii.
• There are 3 active volcanoes – Maunaloa (last erupted in 1984), Kilauea
(constantly erupted) and Loihi (underwater).