Images

HVO staff visited the summit of Mauna Loa on foot to repair the webcam on April 24. The weather was perfectly clear and views of the caldera floor showed nothing unusual.

An HVO geologist walks along the Mauna Loa summit trail, with Mauna Kea visible in the distant background.

HVO scientists inspect a seismic station on Mauna Loa to evaluate for a possible equipment upgrade in the near future.

HVO scientists measure a GPS instrument to ensure its stability during a multi-day deployment in the Kahuku Unit of Hawai‘i Volcanoes National Park.

A high-precision GPS unit (on white "T" in foreground) records its position at a ground control point along Pohoiki Road. This marker was painted in July 2018 and is visible in numerous aerial photographs taken by USGS Hawaiian Volcano Observatory geologists throughout Kīlauea's lower East Rift Zone eruption last summer.

A high-precision Global Positioning System (GPS) survey is completed annually on Mauna Loa. This station was occupied for a period of three days to supplement the continuously operating GPS stations on the volcano. A beautiful view of Mauna Kea (in distance) could seen from this site during the GPS survey. 

Only small amounts of sulfur dioxide (SO₂) and hydrogen sulfide (H₂S) are currently being released from Kīlauea, but they chemically react with each other (oxidation-reduction reaction) to form the bright yellow sulfur deposits visible on the crater walls within Halema‘uma‘u.

Telephoto zoom of the largest sulfur deposit forming on the NE talus wall in Halema‘uma‘u. The view is from the
USGS Hawaiian Volcano Observatory's K3cam. Images can be viewed on HVO's website at https://volcanoes.usgs.gov/observatories/hvo/webcam.html?webcam=K3cam.

A USGS pilot and Hawaiian Volcano Observatory gas geochemist prepare to conduct a test flight of an unmanned aerial system (UAS) on Kīlauea Volcano in November 2018. This UAS was outfitted with a prototype miniaturized multi-gas sensor for the detection of volcanic gases emitted by Kīlauea, including sulfur dioxide and carbon dioxide.

Many of the earthquakes in Hawaii that extend offshore and up the island chain are due to plate bending, or flexure. The upper panel shows magnitude-5 and greater earthquakes since 1861, with some notable events labeled.

Kīlauea Volcano’s 2018 summit collapse, shown here on July 28 (left), and the lower East Rift Zone fissure 8 lava flow, shown here on July 2 (right), will be the focus of “Volcano Awareness Month” talks offered in January 2019.

The USGS Hawaiian Volcano Observatory continues to closely monitor volcanoes and earthquakes on the Island of Hawai‘i. On this map, which shows earthquakes that occurred beneath the island between August 6, 2018, and November 14, 2018, the size of each circle depicts earthquake magnitude and color indicates earthquake depth, relative to mean sea level.

These views of Mauna Loa are from near the Hawaiian Volcano Observatory looking toward the west. The view on left is typical during strong trade winds that blow the plume from Halema‘uma‘u Crater southwest of the summit area. The view on right is common during slack winds that allow vog conditions to develop in the summit area of Kīlauea.

Continued degassing from fumaroles at fissures on Kīlauea Volcano's lower East Rift Zone produce native sulfur crystals when sulfur dioxide and hydrogen sulfide gases react and cool upon reaching the surface. The delicate sulfur crystals are 5–15 mm (0.2–0.6 in) long.

When molten lava encroaches on grassland, forests, or other vegetated land, subsurface pockets of natural gas from the burning plant material can ignite, causing a blast known as a "methane explosion." To avoid this hazard, keep a safe distance—at least tens of yards—from the margin of an active lava flow in vegetated areas.

On the right, a tiltmeter is ready for installation in a shallow borehole. On the left, the tiltmeter is located at the bottom of a 3 to 4 m (10 to 15 ft) borehole lined with a metal casing. The tiltmeter is surrounded by sand to secure it within the borehole so that it does not touch the casing.

Clear day view of Mauna Loa during tradewind conditions from the summit of Kīlauea Volcano.

Earthquakes (red dots) track the progression of the magmatic intrusion from Kīlauea Volcano's middle East Rift Zone to the lower East Rift Zone between April 30 and May 3, 2018. Orange triangles show the locations of fissure 1 (right), which erupted on May 3, and Pu‘u ‘Ō‘ō (left).

Explosive eruption columns of ash rising from Halema‘uma‘u at 11:15 a.m. on May 18, 1924 (top) and at 11:05 a.m. on May 15, 2018 (bottom) look similar.

Map of selected earthquakes beneath a portion of southeast Hawai`i from May 4, 2018 to March 14, 2019, showing principally aftershocks following May 4, 2018 M6.9 earthquake. Black dots indicate epicenters of 13,083 earthquakes located during this time interval; yellow stars show locations of the M6.9 earthquake and the March 13, 2019 M5.5 earthquake.

This preliminary thickness map of Kīlauea Volcano's 2018 lower East Rift Zone lava flows was calculated by subtracting pre-eruption ground surface elevations from post-eruption ground surface elevations mapped with USGS Unmanned Aerial System (drone) flights.