Groundwater Causing Hawaiian Islands to Dissolve From Within, Study Shows

Mountains on the Hawaiian islands are slowly dissolving from within and will turn into a flat, low-lying topography, a new study shows.

Researcher Steve Nelson and his colleagues from Brigham Young University wanted to find out how fast the Hawaiian Islands were moving away and the influence of climate at that rate.

They revealed that Oahu's Koolau and Waianae mountains will be reduced to a low-lying island. Unlike previous assumptions that soil erosion is the main force reducing the mountains, this new study finds that the mountains are dissolving from within due to groundwater.

The research team estimated the amount of mineral material removed by groundwater and stream water on the island of Oahu in Hawaii, and compared them to find out which removed more groundwater.

They found that the removal of mineral material by groundwater was three to 12 times more destructive than by stream water, according to OurAmazingPlanet. 

Experts also collected samples in the field and estimated the total quantity of mass that disappeared from the island each year.

"All of the Hawaiian Islands are made of just one kind of rock," Nelson said in a statement. "The weathering rates are variable, too, because rainfall is so variable, so it's a great natural laboratory."

Currently, there is nothing to worry, as plate tectonics is pushing Oahu toward the northwest, allowing the island to rise at a slow but steady rate.

According to estimates by researchers, Oahu Island will grow for 1.5 million years. After that, groundwater will eventually cause the mountains to dissolve from within and descend to a low-lying landscape.

The findings of the study appear online in the journal Geochimica et Cosmochimica Acta.