The Explosive Truth:
A Volcano's Lifecycle
Audio Tour
Oʻahu’s Volcanoes
Taking a look outside this window, beyond Hawaiian Hall, you see an incredible green mountain. Well, that is actually a volcano! In fact, everything you step on outside was created on a foundation of volcanic rock. Now, humans have made many alterations over the years, but, you get the point.
Here is a tricky question. How many main volcanoes formed Oʻahu? If you guessed three, you are right! Now, unlike Punchbowl crater, Diamond Head crater, and Koko Head crater, which were much smaller eruptions long after the island was created, the three volcanoes that formed Oʻahu were much, much larger. In fact, just 2 million years ago, the Koʻolau mountain range you see in front of you was twice as tall. And its caldera stretched from the eastern side of Kāneʻohe all the way to Waimānalo. On the western side of Oʻahu is the Waiʻanae volcano which, though older than the Koʻolau volcano, stands much taller and has maintained its shield-like shape. This is because it is largely shielded by the Koʻolau volcano from the rains brought to the Islands by northeasterly trade winds. Less is known about the oldest volcano that formed Oʻahu but it is known as the Kaʻena volcano, which is located past the westernmost-point on Oʻahu. The remains of this volcano are submerged completely underwater, which kept its existence unknown until 2014!
What happens to islands as they age? Why doesn’t the Koʻolau volcano look like other shield volcanoes like Haleakalā? Head toward the sound of a waterfall to find out!