You are here

Nāhuku Lava Tube In Hawaiʻi Volcanoes National Park Closed To Study Its Stability

Share
NPS geomorphologists install a crack meter inside Nāhuku in November 2019/NPS, J.Wei

NPS geomorphologists install a crackmeter inside Nāhuku in November 2019/NPS, J.Wei

Nāhuku lava tube in Hawaiʻi Volcanoes National Park is closed until further notice while geologists study its stability in the wake of movement of a large rock slab in the tube.

The lava tube, also known as the Thurston lava tube, has a crack that recently narrowed. A "crackmeter" installed to monitor a fracture near a large overhanging rock slab at the apex of the lava tube detected that it had narrowed by 2.47 millimeters between Saturday and Monday.

The narrowing movement could indicate the crack is adjusting in response to other fractures widening in the lava tube, making the large overhead chunk of rock unstable and potentially dangerous, a park release said. The slab measures about 2.16 x 3.23 meters (7.1 x 10.5 feet) and 20.3 centimeters (8 inches) thick. Further monitoring is required to determine if the lava tube can safely reopen.

On Sunday, National Park Service geomorphologist Dr. Eric Bilderback alerted park management that the crackmeter in the middle of Nāhuku had moved 1.96 millimeters Saturday night over the course of several hours, and had moved another 0.51 millimeters by Monday morning. Park managers closed the lava tube Sunday. 

Bilderback said while the movement is slow and not accelerating, these movements of a large rock slab are unusual in the monitoring record. A return of movement similar to the previous record would need to occur before the lava tube would be considered safe to reopen. It is not clear how long that will take. 

Prior to the fractural changes over the weekend, data from the monitors revealed little change to the cave’s structural integrity showing less than 1 millimeter of movement since November 2019. 

Large rocks in Nāhuku were dislodged during the 2018 eruption and summit collapse of Kīlauea volcano. Two crackmeters were installed in the lava tube’s ceiling to monitor their movement. 

The restrooms near Nāhuku and the parking area remain open. 

Support National Parks Traveler

National Parks Traveler is a small, editorially independent 501(c)(3) nonprofit media organization. The Traveler is not part of the federal government nor a corporate subsidiary. Your support helps ensure the Traveler's news and feature coverage of national parks and protected areas endures. 

EIN: 26-2378789

A copy of National Parks Traveler's financial statements may be obtained by sending a stamped, self-addressed envelope to: National Parks Traveler, P.O. Box 980452, Park City, Utah 84098. National Parks Traveler was formed in the state of Utah for the purpose of informing and educating about national parks and protected areas.

Residents of the following states may obtain a copy of our financial and additional information as stated below:

  • Florida: A COPY OF THE OFFICIAL REGISTRATION AND FINANCIAL INFORMATION FOR NATIONAL PARKS TRAVELER, (REGISTRATION NO. CH 51659), MAY BE OBTAINED FROM THE DIVISION OF CONSUMER SERVICES BY CALLING 800-435-7352 OR VISITING THEIR WEBSITE WWW.FRESHFROMFLORIDA.COM. REGISTRATION DOES NOT IMPLY ENDORSEMENT, APPROVAL, OR RECOMMENDATION BY THE STATE.
  • Georgia: A full and fair description of the programs and financial statement summary of National Parks Traveler is available upon request at the office and phone number indicated above.
  • Maryland: Documents and information submitted under the Maryland Solicitations Act are also available, for the cost of postage and copies, from the Secretary of State, State House, Annapolis, MD 21401 (410-974-5534).
  • North Carolina: Financial information about this organization and a copy of its license are available from the State Solicitation Licensing Branch at 888-830-4989 or 919-807-2214. The license is not an endorsement by the State.
  • Pennsylvania: The official registration and financial information of National Parks Traveler may be obtained from the Pennsylvania Department of State by calling 800-732-0999. Registration does not imply endorsement.
  • Virginia: Financial statements are available from the Virginia Department of Agriculture and Consumer Services, 102 Governor Street, Richmond, Virginia 23219.
  • Washington: National Parks Traveler is registered with Washington State’s Charities Program as required by law and additional information is available by calling 800-332-4483 or visiting www.sos.wa.gov/charities, or on file at Charities Division, Office of the Secretary of State, State of Washington, Olympia, WA 98504.

Add comment

CAPTCHA

This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Image CAPTCHA
Enter the characters shown in the image.

The Essential RVing Guide

The Essential RVing Guide to the National Parks

The National Parks RVing Guide, aka the Essential RVing Guide To The National Parks, is the definitive guide for RVers seeking information on campgrounds in the National Park System where they can park their rigs. It's available for free for both iPhones and Android models.

This app is packed with RVing specific details on more than 250 campgrounds in more than 70 parks.

You'll also find stories about RVing in the parks, some tips if you've just recently turned into an RVer, and some planning suggestions. A bonus that wasn't in the previous eBook or PDF versions of this guide are feeds of Traveler content: you'll find our latest stories as well as our most recent podcasts just a click away.

So whether you have an iPhone or an Android, download this app and start exploring the campgrounds in the National Park System where you can park your rig.