Images

On the left is a normal photograph of the ocean entry, which produces a robust steam plume and an area of discolored water extending out from the entry point. The thermal image on the right shows how this area of discolored water corresponds to scalding water temperatures.

A close up view of where approximately 4 acres of old sea cliff fell into the ocean during the delta collapse on December 31. The far eastern end of this collapse (right), is where the old public viewing area was located prior to the collapse.

Another view of the ocean entry, with the plume of hot water extending out from the ocean entry point.

Annotated photograph of Bogoslof Island showing the cumulative effects of 2016-17 eruptive activity. A layer of fine muddy appearing ash drapes most of the landscape and covers pre-existing vegetation. The dashed line indicates the area excavated by explosive eruptive activity so far.

Pele's hair, filaments of volcanic glass, formed from the explosive interaction of hot lava entering the ocean, accumulates on the lava surface above the ocean entry. Some is also blown far downwind of the ocean entry.

Part of what's left of the eastern Kamokuna lava delta following the New Year's Eve collapse can be seen in the center foreground of this image. Visible cracks on the surface of this rocky shelf indicate potential instability and serve as reminders for visitors to the lava viewing area to heed all warning signs.

A closer view of lava cascading from the lava tube at the Kamokuna ocean entry, with spatter (fragments of molten lava) and black sand (volcanic glass) being thrown skyward.

A glove provides scale for spatter (lighter gray, shiny fragments) that landed on the sea cliff above the Kamokuna ocean entry.

Mount St. Helens in December 2004, a few months after the start of the volcano's most recent eruption, as seen from the Johnston Ridge Observatory in Mount St. Helens National Volcanic Monument in Washington. Inset: The USGS Cascades Volcano Observatory in Vancouver, WA, monitors volcanoes in Washington, Oregon, and Idaho. USGS photos.

A telephoto lens captured the cascade of lava streaming from the lava tube. Hot lava mixing with cool seawater produces an explosive interaction that results in fragmented lava—spatter, Pele's hair, and black sand—flying upward, landing on the sea cliff above the ocean entry and being thrown seaward.

This map updates the preliminary ocean entry map below, based on mapping conducted on January 3, 2017. The map of the coastline at the lava flow ocean entry at Kamokuna shows the areas of the lava delta and adjacent coastline that collapsed into the ocean on December 31, 2016.

The rocky shelf at the base of the sea cliff is all that remains of the Kamokuna lava delta following the New Year's Eve collapse (Dec. 31, 2016), which sent acres of rock plunging into the sea.

In addition to most of the Kamokuna lava delta disappearing into the ocean on New Year's Eve day, a large section of the older sea cliff east of the delta also collapsed. Here you can see the "bite" taken out by the collapse of the sea cliff.

This map shows the coastline at the Kamokuna lava entry on Kīlauea Volcano, with labels denoting areas impacted by the large, progressive lava-delta collapse on December 31, 2016. Nearly all the Kamokuna lava delta collapsed into the sea, along with a large section of the older sea cliff east of the delta.

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. USGS photos by A. Lerner, 2018.

White laze plumes mark locations where lava enters the ocean over a broad area. An open lava channel flows into the ocean at the southern-most plume (middle) near the southern flow margin. The boat ramp at Pohoiki is about 940 m (0.58 mi) farther south of the flow margin. View is toward the west-southwest.

Allan Lerner works in the USGS volcanic gas geochemistry group. The photo was taken in the crater of Mount St. Helens, with Spirit Lake and Mount Rainier in the distance. USGS photo by P. Kelly.

GeoGirls hike onto the Pumice Plain to learn more about Mount St. Helens’ historical

eruptions.

High-resolution digital elevation dataset for Newberry Volcano and vicinity, Oregon, based on lidar survey of August-September, 2010 and bathymetric survey of June, 2001.

Flow banding of Panum pumice and obsidian of the same composition.

Photograph of eddy covariance and Multi-GAS stations that were deployed in a temporary configuration near Norris Geyser Basin in 2016. Research conducted under permit YELL-2016-SCI-7082.