Images

Very few surface flows have been observed in Pu‘u ‘Ō‘ō crater over the past month, but the crater today was far from quiet. The spatter cone shown here, in the northern portion of the crater, was producing a loud, continuous jetting sound resulting from gas being forced through a tiny opening at the peak.

Active pāhoehoe breakouts are scattered across portions of the Kahauale‘a 2 flow. This photo shows a nice example of ropy pāhoehoe active near the flow margin.

USGS scientists Craig Weiss and Michael Scheider make a streamflow measurement at Onion Creek at U.S. Highway 183 in Austin, TX.

USGS scientist Monica Langhorst measures gage height with a wire weight at Onion Creek at U.S. Highway 183 in Austin, TX.

USGS scientist Monica Langhorst measures gage height with a wire weight at Onion Creek at U.S. Highway 183 in Austin, TX.

USGS scientist Mark Warzecha makes a streamflow measurement with Acoustic Doppler Current Profiler downstream of a USGS streamgage station on the Blanco River at Interstate 35. The streamgage is not currently accessible, so a measurement is being made at the safest downstream location. 

Crews test two methods of measuring discharge of the Muddy River near Mount St. Helens, Washington. The computer and tethered orange float create a vertical discharge profile; the hand-held flow tracker confirms the data. Data collection is becoming more electronic-oriented with periodic confirmation of results by physical observations.

Information regarding magma formation, mixing and its ascent to the surface can be deduced from examination of thin sections (thin slices of rock mounted on glass). Science teachers look on as a sample of basalt is viewed under a petrographic microscope.

A wider view of the Kahauale‘a 2 flow margin at the forest boundary.

An HVO geologist shields his face from the intense heat as he takes a sample of active lava on the Kahauale‘a 2 flow. The chemistry of the lava is analyzed through time and used to study changes in the magmatic system.

pāhoehoe lava on the Kahauale‘a 2 flow invades the forest northeast of Pu‘u ‘Ō‘ō, burning and toppling trees and creating plumes of smoke.

This thermal image looks southwest towards the vent on Pu‘u ‘Ō‘ō, and shows much of the Kahauale‘a 2 flow. Hotter colors (yellow and white) represent active breakouts, while warm colors (red and purple) show recently active portions of the flow.

A close-up view of one of the many breakouts of pāhoehoe on the Kahauale‘a 2 flow.

This thermal image looks southwest towards the vent on Pu‘u ‘Ō‘ō, and shows much of the Kahauale‘a 2 flow. Hotter colors (yellow and white) represent active breakouts, while warm colors (red and purple) show recently active portions of the flow.

Repairs are made to an Acoustic Flow Monitor (AFM) located at the confluence of the North Fork Toutle River, Maratta, Castle and Coldwater Creeks, where the most recent lahar occurred in November, 2006. AFMs are installed to "hear" when lahars [muddy debris flows] move down channel so affected communities can be warned of the hazard.

The deep-sea drilling ship Chikyu, which will attempt to drill through the Moho [Image copyrighted by JAMSTEC. Used with permission].

Image of ripples in sand, next to a rocky surface on the seafloor 2.5 km (1.5 miles) offshore San Mateo County, California at a depth of 24.6 meters (81 feet). The two red dots in the image (from lasers mounted on the camera and used as reference points) are 15 cm (6 inches) apart.

The Kahauale‘a 2 flow is fed from a spatter cone, shown here, on the northeast edge of Pu‘u ‘Ō‘ō's crater floor. The spatter cone is about 8 m (26 ft) high.

The Kahauale‘a 2 flow extends to the north and northeast of Pu‘u ‘Ō‘ō. From the edge of the flow, where it first reaches the forest, Pu‘u ‘Ō‘ō still appears to tower above the surrounding plain.

The lava lake in Halema‘uma‘u has fallen slightly over the past few weeks. It is now about 55 m (180 ft) below the surrounding crater floor.

The Kahauale‘a 2 flow extends to the north and northeast of Pu‘u ‘Ō‘ō. From the edge of the flow, where it first reaches the forest, Pu‘u ‘Ō‘ō still appears to tower above the surrounding plain.