Images

GeoGirls learn about how the May 18, 1980 eruption of Mount St. Helens impacted the ecology of the area.

Photomicrograph of sample 09RDWES301 - an andesite collected during the Redoubt 2009 eruption. A rock thin section is created by gluing a small piece of rock onto a glass slide, then grinding it down to a thickness of 30 microns (the average human hair is about 100 microns in diameter) so that light shines through it when examined under the microscope.

On May 24, 2016, two new flows broke out on the flanks of the Pu‘u ‘Ō‘ō cone on Kīlauea Volcano's East Rift Zone. The silvery sheen of new lava erupting from the northern 61f breakout (center) and eastern 61g breakout (upper left) stands out in contrast to the older flows on and around Pu‘u ‘Ō‘ō (right).

This building housed the Kīlauea cyclorama at the Chicago World's Fair in1893. Positioned above the entrance to the cyclorama was a statue of Pele, the Hawaiian volcano goddess, standing on a lava flow and holding a flame. For more info, please see https://chicagology.com/columbiaexpo/fair052/.

This map shows recent changes to Kīlauea's East Rift Zone lava flow field. The area of the active flow field as of November 29 is shown in pink, while widening and advancement of the active flow as of December 14, based on satellite imagery, is shown in red. Older Pu‘u ‘Ō‘ō lava flows (1983-2016) are shown in gray.

December 13 - 14, 2016 Long Valley Caldera earthquake swarm recorded on instrument MDH1 webicorder. Swarm begins at 23:28 PST.

In July 2016, lava erupted from Kīlauea Volcano's East Rift Zone reached the ocean for the first time in almost three years, building the Kamokuna lava delta, shown here in October 2016.

This video, at 50x speed to illustrate the motion of the lava lake surface, shows typical lava lake activity within Halema‘uma‘u Crater. Lava upwells in the northern portion of the lake (left side of image), with most of the lake surface flowing towards the south (right side). Spattering is active within a small grotto at the southeast margin of the lake.

As you watch this VIDEO CLIP, note the rocky ledge (yellow arrow) at the bottom of the webcam image. At 6:58 a.m., HST, today, this large slab of the summit vent wall, located directly below HVO's HMcam, collapsed.

USGS Hawaiian Volcano Observatory geologist Frank Trusdell (right) discusses methodologies for lava flow hazard assessment in Hawaii with a volcanology colleague from Ethiopia during the recent Volcano Observatory Best Practices Workshop in Vancouver, Washington.

The U.S. Geological Survey Hawaiian Volcano Observatory and the National Park Service Jaggar Museum are perched together near the summit of Kīlauea, about 1.7 km (~1.1 mi) from the lava lake in Halema‘uma‘u, producing a plume in the background.

A wide view of the ocean entry, showing the broad lava delta on the right. Lava deltas (new land formed at the ocean entry) are built on a foundation of rubble, so they can (and do) collapse without warning.

Another view of Halema‘uma‘u with its lava lake. The view is to the southeast.

Large cracks parallel to the shoreline are still visible on the Kamokuna delta, indicating instability. The view is to the northeast.

Lava is transported to the Kamokuna ocean entry, its plume is visible in the distance, via a lava tube. The trace of an active lava tube is often identifiable by a line of fume, as seen here for the episode 61g lava tube above the Pūlama pali.

A close-up of one of several streams of lava entering the ocean at the front of the Kamokuna lava delta on Kīlauea's south flank. The billowy white plume formed by the interaction of hot lava and seawater may look harmless, but it is a mixture of superheated steam, hydrochloric acid, and tiny shards of volcanic glass—all of which should be avoided.

Lava continues to enter the ocean at Kamokuna, where a lava delta about 19 acres in size has been built. The gravel emergency access road is visible on both sides of the surface flow that cut it. The view is to the southwest.

A breakout from the episode 61g vent at the head of the lava tube on November 21 sent lava streaming downslope. That breakout was still active when observed on November 29 and had traveled about 1.3 km (0.8 miles), partly surrounding Pu‘u Halulu, a tephra cone formed in 1983 at the start of the Pu‘u ‘Ō‘ō eruption.

Kīlauea's summit lava lake in Halema‘uma‘u is about 255 m (~840 ft) long (left to right in the image) and 195 m (~640 ft) wide. From this perspective, magma rises into the lake near its north edge (upper left) and circulates to the south, where it sinks all along the south margin of the lake.

This map shows recent changes to Kīlauea's East Rift Zone lava flow field. The area of the active flow field as of November 3 is shown in pink, while widening and advancement of the active flow as of November 29 is shown in red. The new flow branch east of Pu‘u ‘Ō‘ō started from a breakout at the episode 61g vent on November 21.

Graphic shows an east to west cut-away of Mount St. Helens with an interpreted model of seismic wave speeds under the volcano and earthquakes from 2008-2016. The colors of the model represent changes in seismic p-wave velocities from tomographic studies (Waite and Moran, 2009; doi:10.1016/j.jvolgeores.2009.02.009).