Mauna Loa
Multimedia
Map showing subaerial extents of historical Mauna Loa lava flows
Map showing the subaerial extents of historical lava flows from Mauna Loa. Lava flow hazard zones and districts of the County of Hawai‘i are also depicted.
Aerial view of a bomb detonating on Mauna Loa lava flows
Aerial view of a bomb detonating on Mauna Loa near the source of the 1935 Humu‘ula lava flow on the morning of December 27, 1935. This was one of 20 demolition bombs dropped on the lava flow that morning by the Army Bombing Squadron from Luke Field, O‘ahu.
U.S. Army Air Corps biplane prepares to drop bombs on 1935 lava flow
A U.S. Army Air Corps biplane is prepared for a mission to drop bombs on a lava flow advancing toward Hilo during the Mauna Loa 1935 eruption. Below the plane is one of 20 demolition bombs (center) dropped in an attempt to disrupt and redirect the Humu‘ula lava flow, and two of the 20 "pointer bombs" (left and right) that were used for aiming purposes.
Scientists examine an outcrop of ash in Hilo
USGS Hawaiian Volcano Observatory scientists examine an outcrop of reddish-brown Hilo ash during a recent study to investigate the origins of volcanic ash deposits on the Island of Hawai‘i. Age dates of lava flows above and below the Hilo ash deposit indicate that the ash was erupted between 3,000 and 14,000 years ago.
What will you do when Earth’s largest active volcano erupts?
In 2019, the Volcano Alert Level for Mauna Loa was elevated from “NORMAL” to “ADVISORY” due to increased seismicity and deformation at the volcano. This alert level does not mean an eruption is imminent, but it is a fact that Mauna Loa, which has erupted 33 times since 1843 (most recently in 1984), will erupt again. What will you do when it does? USGS Hawaiian Volcano
Cross-caldera Distance Change - Past Year
Cross-caldera Distance Change - Past Year
Earthquake Rates - Past Year Mauna Loa
Earthquake Rates - Past Year Mauna Loa. Number of earthquakes per week during the past year (blue bars). The red line is the cumulative moment (energy) release.
Cross-caldera Distance Change - Past 5 Years
Cross-caldera Distance Change - Past 5 Years
Earthquake Depths - Past Year Mauna Loa
Earthquake Depths - Past Year Mauna Loa. Depth of earthquakes during the past week in the area shown on the map above. On both figures, circle-size represents magnitude, and color indicates depth.
Cross-caldera Distance Change - Past Year Mauna Loa
Cross-caldera Distance Change - Past Year Mauna Loa. Changes in distance between two GPS stations on opposite sides of MOKUAWEOAWEO, Mauna Loa's summit caldera. Extension across the caldera is often an indication of inflation of the shallow summit magma reservoir.
