Why are volcanoes everywhere on the Hawaiian islands?
Volcanoes are usually found near the boundaries of the tectonic plates that make up the Earth’s crust. However, the Hawaiian islands are located far from Pacific plate. So, why are there volcanoes in Hawaii? That’s a good question.
People know Hawaii as the dream vacation spot, not as a dangerous hub for active volcanoes. In order to answer the question “why are there volcanoes in Hawaii“, we’ll lay out a few geological facts. The next time you visit the flaming paradise, you’ll stare out the window on a helicopter tour and have a whole new perspective on how the islands came to be.
What are volcanoes, exactly?
A volcano is a geological structure with an opening, where molten rock, volcanic ash, and gases escape from below the Earth’s crust during an eruption. Magma forms from hot molten rock and erupts as lava once it reaches the surface. Once lava cools it creates volcanic rock. Eruptions and lava flows add shape and height to the volcanoes.
Volcanoes come in three variations, recognizable by their shape: Shield, Cinder Cones & Stratovolcano. While you may instantly identify some for their distinct form (think of Mt. Fuji in Japan), a shield volcano has a less obvious appearance from away. If it weren’t for the constantly oozing lava and aerial views, spectators wouldn’t automatically recognize Mauna Loa (a shield volcano) as a volcano.
Volcanoes are also classified by activity level according to the frequency of eruptions. They can be active, dormant or extinct.
Active: Those that erupt regularly or show activity in recent history are considered active.
Dormant: Erupted in the past and will likely erupt again, but doesn’t show signs of activity.
Extinct: No longer has a magma supply and will not erupt again.
The Earth’s crust is made up of several tectonic plates. Movement of these plates can cause openings in the Earth’s surface. This allows magma to rise and volcanoes to form near the plate boundaries. It’s the most common way for volcanoes to form.
Which is why Hawaii seems confusing… after all, it’s nowhere near the Pacific plate boundaries.
Here’s the thing…
Volcanoes can also form in other areas, away from plate boundaries. This is what happened with Hawaii. And it happens because of something called hotspots.
Why are there volcanoes in Hawaii? The answer is hotspots.
A hotspot is a plume of hot magma that originates in the lower mantle of the earth and rises to the surface. The hot magma weakens the Earth’s crust and causes eruptions. The magma released creates volcanic rock which builds up over time.
The hotspot below the Pacific Ocean has gradually formed Hawaii.
The slow movement of the plate over this hotspot causes volcanic activity. Over time, it led to the creation of the Hawaiian-Emperor seamount chain and the Hawaiian islands. The tops of the volcanoes and volcanic mountains that rise above sea level form the 8 main Hawaiian islands and the smaller islets.
The Volcanoes of Hawaii
There are five active volcanoes.
Mauna Loa is the largest active volcano in the world, yet Kilauea is the most active in Hawaii. The others include Hualalai, Haleakala, and Lo´ihi.
The two most active volcanoes are currently Kilauea and Lo’ihi. Since 1983, Kilauea has been active with regular reports of lava lake overflows in the crater. Lo’ihi is still submerged underwater, as an active volcano in the Hawaiian-Emperor seamount chain. The last major eruption of Lo’ihi was in 1996 with intermittent activity seen since then.
Rather than wondering “why are there volcanoes in Hawaii“, you’ll now be able to share your newfound wisdom with friends and family. How can you see volcanoes in action? You can follow updates on Hawaii volcanic activity, or make the most of the opportunity by booking a Doors Off Adventure tour. You’ll get to fly through the rainforest and over lava. You won’t want to miss this Hawaiian experience!