Unified Interior Regions


The Pacific Region has nine USGS Science Centers in California, Nevada, and Hawaii. The Regional Office, headquartered in Sacramento, provides Center oversight and support, facilitates internal and external collaborations, and works to further USGS strategic science directions.

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December 21, 2009

Filling and draining cycle event in the Halema`uma`u vent

Lava within the vent cavity in Halema`uma`u crater continues to be active, and occasionally displays remarkable filling and draining cycles. This Quicktime movie shows the draining portion of one of these cycles, captured in "nightshot" mode in order to see through the thick fume. The video begins with a wide surface of chaotic, agitated lava, with vigorous upwelling and

Image: Aerial of Active Kilauea Area
December 17, 2009

Aerial of Active Kilauea Area

An aerial view looking north at two active areas of Kīlauea. Pu`u `Ō `ō crater is in the foreground, Mauna Loa (left) and Mauna Kea (right) are in the background. The fume source near the base of Mauna Loa (at Kīlauea's summit) is from the Halema`uma`u Overlook vent. The wind is blowing the plume trace toward the northeast, partially obscuring the view of Mauna Kea.

Image: Explosive Kilauea Boulder
December 8, 2009

Explosive Kilauea Boulder

This large rock at the Kīlauea Overlook in Hawai‘i Volcanoes National Park was ejected ballistically in 1790, or soon thereafter, from Kilauea Volcano's summit caldera when it was more than 600 meters (2000 feet) deep.

November 21, 2009

Small explosive event in the Halema`uma`u vent

movie (at x2 speed) shows a small explosive event in the Halema`uma`u vent at 9:20am. The explosion was immediately preceded by a portion of the vent rim collapsing into the vent cavity. The brown plume rises rapidly from the vent, and in the full resolution video large particles can be seen ejected in front of the plume. In the video shown here, it is possible to see some

November 19, 2009

Lava within the Halema`uma`u vent cavity

movie shows lava within the Halema`uma`u vent cavity, at a depth of about 200 m below the vent rim. The lava surface, which is about 20 m wide, is extremely vigorous, with constant roiling and semi-continuous spattering. Spatter deposited on the walls around the lava surface creates a hot, unstable surface, which can be seen to disintegrate as large blocks break off and

Aerial view of Pu‘u ‘Ō‘ō and surrounding features
November 1, 2009

Aerial view of Pu‘u ‘Ō‘ō and surrounding features

Aerial view of Pu‘u ‘Ō‘ō and surrounding features.

Attribution: Kīlauea
October 3, 2009

Disappearance of the lava pond within Halema`uma`u

movie shows the disappearance of the lava pond deep within the Halema`uma`u vent cavity during the early morning hours of October 3. The lava surface undergoes two filling and draining cycles, and then retreats to deeper levels in the conduit, completely out of view, around 2 am.

October 2, 2009

Cycles of filling and draining within Halema`uma`u

movie shows lava pond activity within the Halema`uma`u vent cavity captured with the low-light camera situated at the Halema`uma`u Overlook. The entire night of Oct 1-2, 2009, is shown here in 26 seconds, so the speed of the video is increased considerably. You can see many cycles of filling and draining, with each cycle lasting about two hours. There is also alternating

October 1, 2009

Fluid motion of pāhoehoe flow at Royal Gardens subdivision

This video shows the remarkable fluid motion of a finger of pāhoehoe flowing into an old skylight at the top of Royal Gardens subdivision. The movement of the viscous lava resembles that of soft-serve ice cream.

September 30, 2009

Collapse of the unstable walls within Halema`uma`u vent

movie shows two separate rockfalls impacting and disrupting the active lava pond in Halema`uma`u. Rockfalls here result from collapse of the unstable walls of the vent cavity, and are a common occurrence. The first rockfall impacts the lava surface vertically, while the second features small vertical impacts followed by a slide of material that forces the lava surface to

September 30, 2009

Vigorous spattering deep within Halema`uma`u vent

movie shows vigorous spattering at the northeast margin of the lava pond that is deep within the Halema`uma`u vent cavity. The lava surface, cut by incandescent cracks, is slowly migrating towards the southeast (down in this image). The lava pond has been visible the last several nights in the Halema`uma`u Overlook webcam (see 'webcams' link above).

September 29, 2009

Spattering deep within Halema`uma`u vent

movie shows spattering on the northeast margin of a small lava pond deep within the Halema`uma`u vent cavity. The video was shot in "nightshot" mode, which provides improved views through the thick fume at night. Each spatter burst represents a gas bubble, or bubbles, breaking at the surface.

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photo of lave
August 5, 2003

Lava does the two step: Holei and Paliuli

August 3, 2003

An eruption on May 24, 1969, created a wonderful but underappreciated visitor attraction in Hawai`i Volcanoes National Park, accessible to almost everyone by a 10-minute walk from the Chain of Craters Road.

photo of lave
August 1, 2003

Sweeping breakout 600 m from Paliuli and later aerial views

July 31, 2003

It's an easy question to answer, "how old is the youngest volcanic rock on the Big Island?" With Kīlauea in virtually continuous eruption, the youngest products are "right now!" But what of the other Hawaiian islands?

photo of lave
July 27, 2003

Scenes of lava in western tongue of Kohola

July 24, 2003

It was heartening to see several delegates at last week's Cities on Volcanoes 3 (COV3) conference who were former students of the Center for the Study of Active Volcanoes (CSAV) at the University of Hawai`i at Hilo. Every summer, CSAV conducts two training sessions.

photo of lave
July 22, 2003

Aerial views of skylight and active flow field