Images

Lava-flow hazard zones map, Island of Hawai‘i. See Full Map for complete legend.

Map of hazard zones for ground fractures and "small-scale" subsidence for the Island of Hawai‘i. Subsidence and fracturing events are frequent in zone 1, which covers the summit and rift zones of Kīlauea and Mauna Loa volcanoes, but are somewhat less frequent in zone 2, on the south flank of Kīlauea.

Simulated fractures and subsidence above a widening dike (dark area at bottom) were generated in a small-scale model using a box filled with flour, sugar, and corn meal. The simulated dike (tip is dark area bottom center of photograph) consisted of two linoleum sheets taped together.

Coconut grove and campground on the southern shoreline of Kīlauea Volcano at Halapē before 1975 magnitude 7.7 earthquake. Halapē was a popular hiking destination in Hawai‘i Volcanoes National Park.

This part of the south flank of Kīlauea Volcano moved seaward about 6 m (20 ft) and subsided about 3.5 m (11.5 ft) as a result of the magnitude-7.7 earthquake. A tsunami swept ashore at Halapē and reached 14.6 m (48 ft) above the post-earthquake shoreline.

Seismic hazard across the State of Hawaii, with high seismic hazards depicted with warm colors (red-orange) and relatively low seismic hazards depicted with cool colors (green). Engineers use these types of maps to prescribe building codes known as Seismic Design Codes (SDC) and create earthquake resistant structures.

Top: Photograph of the SO2 camera installation when scientists tested the radio link to the Hawaiian Volcano Observatory (HVO). The camera is aimed at the plume emitting from the Overlook Crater, about 1.4 km away. Under typical trade wind conditions, the plume is blown to the southwest, thus moving from right to left in the imagery.

GPS measurements provide models of the direction and rate (length of arrow) of deformation at the summit of Mauna Loa. Arrows pointing in multiple directions away from the summit indicate inflation.

The Uwekahuna WT (water-tube) instrument is still measured today, providing one of the longest records of deformation for any volcano. The tiltmeter is read by looking into the portal on each pot and adjusting the sight until two pins appear to touch.

Seismic station locations (red triangles) on the Island of Hawai‘i and across the State of Hawaii (inset).

HVO seismologists use this to review automatically generated earthquake parameters (location, depth, magnitude), measure P- and S-wave arrival times, and re-compute earthquake hypocenter and magnitudes for cataloging and distribution to the public.

Earthquakes near the Island of Hawai‘i between 1970-2006 with magnitude greater than 2.5. A (top left): locations of shallow earthquakes 0-22 km (0-14 mi) depth. B (top right): locations of deep earthquakes 22-55 km depth (14-34 mi). Bottom (C): cross section showing the depths of earthquakes in the rectangle in figure B.

Big Pine Volcanic Field, California, from southwest cinder cone, with US Route 395 and Owens River in view

Crater Lake, Oregon simplified hazards map showing potential impact area for ground-based hazards during a volcanic event.

Mount Bachelor seen from South Sister across Sparks Lake. One of the "Devils Chain" domes visible in lower image foreground. Oregon

Mount Bachelor viewed from the south. Sparks Lake and South Sister visible in the background. Oregon.

Mount Bachelor's east facing ski slopes at sunrise.

The Uwīkahuna WT (water-tube) instrument is still measured today, providing one of the longest records of deformation for any volcano. The tiltmeter is read by looking into the portal on each pot and adjusting the sight until two pins appear to touch.

Slope map of Mauna Loa, including lava flows erupted since 1823 (gray), showing the approximate number of hours or days it took for a flow to advance from the vent location to the ocean or maximum reach of a flow. One flow that moved down the steep slopes on west flank of Mauna Loa reached the ocean in as little as 3 hours after the vent started erupting in 1950.

Volume of products, eruption cloud height, and qualitative observations (using terms ranging from "gentle" to "mega-colossal") are used to determine the explosivity value. The scale is open-ended with the largest volcanic eruptions in history (supereruptions) given magnitude 8.

Mount Hood in the not-so-far distance beyond Downtown Portland, Oregon. Photograph taken at the top of the Portland Aerial Tram line on Marquam Hill.