Most of us think of soil erosion as the primary force that levels mountains, however geologists have found that Oahu's mountains are dissolving from within due to groundwater.
Someday, Oahu's Koolau and Waianae mountains will be reduced to nothing more than a flat, low-lying island like Midway.
But erosion isn't the biggest culprit. Instead, scientists say, the mountains of Oahu are actually dissolving from within.
"We tried to figure out how fast the island is going away and what the influence of climate is on that rate," said Brigham Young University geologist Steve Nelson. "More material is dissolving from those islands than what is being carried off through erosion."
Read more here: http://www.sciencedaily.com/releases/2012/12/121221114044.htm