Hawaii is one of the United States' most talked-about destinations, with its lush tropical rainforests, remote and colourful beaches, celebrated Polynesian culture, and unparalleled volcanic landscapes. Though it's high on the list for many tourists, not a lot people actually know the island state's remarkable history or how this famously beautiful landscape was formed.
First, it must be established that the Hawaiian Islands are of volcanic origin. Each island has at least one primary volcano, but many islands have more than one. Hawaii's Big Island is one such example; it's a composite of five major volcanoes including Mauna Loa, the largest active volcano in the world! It is volcanoes such as these shield volcanoes which give Hawaii its signature, soft-sloping lava flows.
The story of Hawaii started around 5 million years ago, with rumblings deep in the ocean. Many people know that there is a lot of volcanic activity around the edges of Earth's tectonic plates, but they can also form any place where a plume of magma rises upward until it erupts on the sea floor. Eruption upon eruption occurs in the murky ocean depths and hardened lava piles higher and higher until the island reaches above the sea, where it can be crowned an official piece of land. This is how Hawaii was born, in a so-called "hot spot" in the middle of the Pacific Plate.
It is a bit more complicated than this, however, as Hawaii is not just one contiguous entity. It is often thought of as a handful of islands, but in reality the Hawaiian archipelago includes 132 islands, atolls, reefs, shallow banks, shoals, and sea-mounts - an impressive collection of geological wonders which spans a whopping 1,500 miles.
However, it is obvious that there are eight major islands, so now the question is this: how did each island form and why is there more than one? Well, the Pacific Plate kept moving, as all tectonic plates do, at a crawling pace of mere single-digit centimetres per year. Slow and steady, the Pacific Plate moved while the "hot spot" below the bubbling sea floor stayed put, lending its hand in the creation of each of the major Hawaiian Islands. You can use this fact to figure out the islands' relative ages: the more Northwest a Hawaiian island is, the older it is.
Following this logic, one begins to realize that if the hot spot is still there and the Pacific Plate is still moving, shouldn't it keep creating new Hawaiian islands over hundreds of thousands of years? Absolutely! In fact, what will possibly become the newest Hawaiian island is currently a sea-mount (or submarine peak) called Loihi, and it is being formed before our eyes via constant volcanic eruption from its summit.
This amazing geological spectacle is not one that curious tourists can witness, however. Currently, Loihi still lies below the surface of the ocean, at a depth of about one thousand meters. While geologists have found that Loihi's growth rate is comparable to those of the other Hawaiian volcanoes, there is no guarantee that Loihi will ultimately rise above the surface of the ocean and become a new island. Even if it is destined to become the next link in the Hawaiian chain, Loihi will take tens of thousands of years to reach the top. And if Loihi never sees the light of day, it will take even longer for a new Hawaiian island to form.
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