Hawaiian Volcano Observatory


Filter Total Items: 1,690
Color photograph of soil and ash
March 26, 2020

This section of brown Icelandic soil and ash

This section of brown Icelandic soil (top) contains 800 years of ash deposits erupted from five different volcanoes. The black layers, 5-10 cm (2-4 in) thick, are from Katla Volcano. A white arrow points to a closeup of the 1755 Katla ash deposit (lower left). The ash looks like specks of dust in the sample bag (lower right), but microprobe imaging reveals how complex

Black and white SEM image of ash
March 26, 2020

Scanning electron microprobe images of Icelandic ash

Scanning electron microprobe images show the complexity of tiny Icelandic ash grains (150 micron, or 0.006 inch). Image (a) shows a dense and blocky grain, and (b) shows a foamy grain.

Black and white photograph of bomb on lava flow
March 4, 2020

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.

Black and white photograph of plane with bombs
March 4, 2020

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. 

Color photograph showing ash outcrop and two scientists
February 6, 2020

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. 

Scientist holds rope leading to Unoccupied Aircraft System
January 31, 2020

Unoccupied Aircraft System with water sampler

The sampling mechanism (on blue tarp) is prepared and the Unoccupied Aircraft System (UAS) is inspected just before take off to collect water from the Halema‘uma‘u crater lake. Brightly colored flagging tape tied to a cable attached to the UAS indicated depth as the sampling tool was lowered into the water. 

Color photograph of seismologist in field
January 30, 2020

Geophysicist Brian Shiro, USGS Hawaiian Volcano Observatory

Geophysicist Brian Shiro, manager of the USGS Hawaiian Volcano Observatory's seismic network, was part of HVO's team that installed several new stations on Kīlauea Volcano's lower East Rift Zone to monitor earthquakes during the 2018 eruption. The station they installed here, ERZ1, was eventually overrun by lava, but it provided important data while it lasted. 

January 29, 2020

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

January 28, 2020

Seismicity of the 2018 Kīlauea Volcano eruption

The 2018 Kīlauea eruption produced unprecedented levels of seismicity in the volcano’s instrumented history. The USGS Hawaiian Volcano Observatory documented about 80,000 earthquakes during the three-month-long eruption, starting with the dramatic collapse of the Puʻu ʻŌʻō cone on April 30 and ending with the final Kīlauea summit caldera collapse event on August 5. The

Color photograph of native Hawaiian plant and fluxmeter
January 24, 2020

Portulaca sclerocarpa and WEST Systems fluxmeter

This Portulaca sclerocarpa (‘Ihi mākole) individual (center) surrounded by invasive grass species is a critically endangered plant. The small metal tag to the right notes the plant's permanent identification number for long-term monitoring purposes. A WEST Systems fluxmeter (chamber at top) measures carbon dioxide emissions on the soil surface and a probe (black

Color photograph of scientists
January 24, 2020

Team investigating critically endangered plant in Puhimau Thermal area

Retired USGS botanist Linda Pratt, USGS research geologists Patricia Nadeau and Jennifer Lewicki, and USGS chemist Tamar Elias (left to right) are part of a team investigating a critically endangered succulent plant, Portulaca sclerocarpa, in Hawai‘i Volcanoes National Park's Puhimau thermal area. Invasive species, like the broomsedge grass shown here, may contribute

Color photographs of volcanic gas monitoring
January 23, 2020

Hawaiian Volcano Observatory volcanic gas monitoring

As fissure 8 erupts on Kīlauea Volcano's lower East Rift Zone in June 2018 (left), a Fourier Transform Infrared (FTIR) spectrometer measures gas emissions from the lava fountains. At right, Hawaiian Volcano Observatory gas geochemistry team members collect a sample of gas from Sulphur Banks in Hawai‘i Volcanoes National Park.