Oahu is dissolving from its inner core in Hawaii, according to Geologists who recently conducted a study on the third largest island to Honolulu. It could mean a big change for the state as the island’s Koolau and Waianae mountains will be reduced to nothing.
When that happens, researchers say that it will leave the island of Oahu nothing but a flat bearing place that has drastically changed.
“We tried to figure out how fast the island is going away and what the influence of climate is on that rate,” said Steve Nelson, a Brigham Young University geologist. “More material is dissolving from those islands than what is being carried off through erosion.”
The study, published in Geochimica et Cosmochimica Acta, looked at both groundwater and stream water, comparing them to see which removes more mineral material. Geologists spent two months sampling both types on Oahu, then added data from the U.S. Geological Survey to calculate the total mass that disappeared from the island in various years.
“All of the Hawaiian Islands are made of just one kind of rock,” said Nelson. “The weathering rates are variable, too, because rainfall is so variable, so it’s a great natural laboratory.”
According to Nelson and his colleagues’ estimates, the plate tectonics affecting Oahu will continue to grow the island for 1.5 million years. After that, groundwater will begin to force the island and its mountains into a flat landscape.
Oahu is home to about 953,207 residents, which is about 75 percent of the populate of the state of Hawaii. The island has for a long time been known as “The Gathering Place.”
What’s also interesting is that the term “Oahu” has no confirmed meaning in Hawaiian, other than that of the island itself.