Featured Research

from universities, journals, and other organizations

Hawaiian Islands are dissolving from within, study says

Date:
December 21, 2012
Source:
Brigham Young University
Summary:
Most of us think of soil erosion as the primary force that levels mountains but geologists have found that Oahu's mountains are dissolving from within due to groundwater.

Someday groundwater will dissolve Hawaii's islands completely.
Credit: Image courtesy of Brigham Young University

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.

Related Articles


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."

The research pitted groundwater against stream water to see which removed more mineral material. Nelson and his BYU colleagues spent two months sampling both types of sources. In addition, ground and surface water estimates from the U.S. Geological Survey helped them calculate 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. "The weathering rates are variable, too, because rainfall is so variable, so it's a great natural laboratory."

Forecasting the island's future also needs to account for plate tectonics. As Oahu is pushed northwest, the island actually rises in elevation at a slow but steady rate. You've heard of mountain climbing; this is a mountain that climbs.

According to the researchers' estimates, the net effect is that Oahu will continue to grow for as long as 1.5 million years. Beyond that, the force of groundwater will eventually triumph and the island will begin its descent to a low-lying topography.

Undergraduate student Brian Selck co-authored the study, which appears in the journal Geochimica et Cosmochimica Acta. Unfortunately for him, he joined the project only after the field work in Hawaii took place.

Instead, Selck performed the mineralogical analysis of soil samples in the lab back in Provo. The island's volcanic soil contained at least one surprise in weathered rock called saprolites.

"The main thing that surprised me on the way was the appearance of a large amount of quartz in a saprolite taken from a 1-meter depth," Selck said.

After he graduates from BYU, Selck will pursue a career in hydrogeology. BYU geology professor David Tingey joins Nelson and Selck as a co-author on the new study.


Story Source:

The above story is based on materials provided by Brigham Young University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Stephen T. Nelson, David G. Tingey, Brian Selck. The denudation of ocean islands by ground and surface waters: The effects of climate, soil thickness, and water contact times on Oahu, Hawaii. Geochimica et Cosmochimica Acta, 2013; 103: 276 DOI: 10.1016/j.gca.2012.09.046

Cite This Page:

Brigham Young University. "Hawaiian Islands are dissolving from within, study says." ScienceDaily. ScienceDaily, 21 December 2012. <www.sciencedaily.com/releases/2012/12/121221114044.htm>.
Brigham Young University. (2012, December 21). Hawaiian Islands are dissolving from within, study says. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2012/12/121221114044.htm
Brigham Young University. "Hawaiian Islands are dissolving from within, study says." ScienceDaily. www.sciencedaily.com/releases/2012/12/121221114044.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Earth & Climate News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Raw: Buffalo Residents Digging Out, Helping out

Raw: Buffalo Residents Digging Out, Helping out

AP (Nov. 22, 2014) Hundreds of volunteers joined a 'shovel brigade' in Buffalo, New York on Saturday, as the city was living up to its nickname, "The City of Good Neighbors." Video provided by AP
Powered by NewsLook.com
Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

AFP (Nov. 21, 2014) Toyota presented its hydrogen fuel-cell compact car called "Mirai" to US consumers at the Los Angeles auto show. The car should go on sale in 2015 for around $60.000. It combines stored hydrogen with oxygen to generate its own power. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Google Announces Improvements To Balloon-Borne Wi-Fi Project

Google Announces Improvements To Balloon-Borne Wi-Fi Project

Newsy (Nov. 21, 2014) In a blog post, Google said its balloons have traveled 3 million kilometers since the start of Project Loon. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins