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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A long skinny core section of mud with a sandy layer in the middle of it lays on the marsh grass near where the core was taken.
December 31, 2015

Ocean sand in wetland core

A vibracore taken from a marshy area in Anahola Valley, Kaua‛i reveals a sandier mud layer.

Image: Endangered Hawaiian Hoary Bat
December 31, 2015

Hawaiian Hoary Bats Hunting Insects

The sound of Hawaiian hoary bats hunting insects.

Attribution: Ecosystems
Sky view of the coastline of a mountainous island with a shallow coral reef that has lots of deep holes and channels.
December 31, 2015

Fringing reef, Kamalo, Molokai

The challenging and complex study environment of Molokaʻi’s (Hawaiʻi) fringing reef. Learn more about USGS studies on this island: “Coral Reef Project: Molokaʻi

Kīlauea Volcano's East Rift Zone eruption turns 33!...
December 31, 2015

Kīlauea's ERZ eruption turns 33!

The November 25, 2015, breakout that began as a rupture from the tube supplying the June 27th lava flow advanced slowly to the northeast of Pu‘u ‘Ō‘ō (background) and reached the forest in mid-December, but still poses no immediate threat to Puna communities. USGS image.

A clear day at Kīlauea's summit...
December 30, 2015

A clear day at Kīlauea's summit

This view shows the north rim of Kīlauea Caldera, with the Hawaiian Volcano Observatory and Hawai‘i Volcanoes National Park's Jaggar Museum perched at the rim for ideal views of summit activity. Mauna Kea is in the distance, partially obscured by clouds, and Mauna Loa's Northeast Rift Zone extends off the left edge of the photo.

A repeating loop showing a hammer scooping lava from a flow and dropping it into a bucket.
September 28, 2015

Lava Sampling

This is an animated GIF, taken from a longer video, showing the moment that this geologist from the Hawaiian Volcano Observatory (HVO) scoops up lava from an active flow and drops it into a bucket of water to cool it down. 

September 28, 2015

Lava Sampling by HVO Geologist

This Quicktime video shows lava sample collection from the perspective of an HVO geologist.


USGS Volcano Alert Level for Mauna Loa Elevated from Normal to Advi...
September 17, 2015

Volcano Alert Level for Mauna Loa Elevated from Normal to Advisory

USGS Hawaiian Volcano Observatory scientists are closely monitoring recent signs of unrest on Mauna Loa, the largest active volcano on Earth. In this 1985 aerial photo, Mauna Loa looms above Kīlauea Volcano's summit caldera (left center) and nearly obscures Hualālai in the far distance (upper right). USGS photo.

Mauna Loa 1975 Eruption...
September 17, 2015

Mauna Loa 1975 Eruption

After 25 years of slumber, Mauna Loa woke with a spectacular, but short-lived, eruption that began just before midnight on July 5. Lava fountains soon erupted from fissures extending across the length of Moku‘āweoweo, Mauna Loa's summit caldera, and into the upper ends of the volcano's northeast and southwest rift zones. After only 6 hours, the caldera and southwest rift

Mauna Loa - Earthquake and Deformation Data 2010-2015...
September 17, 2015

Mauna Loa - Earthquake and Deformation Data 2010-2016

TOP: Mauna Loa weekly earthquake rates between 2010 and September 17, 2015. Blue bars indicate the number of earthquakes that were located by the USGS Hawaiian Volcano Observatory seismic network. Earthquakes of all magnitudes are plotted. Subtle increases in earthquake rates started in mid-2013, while more obvious changes in rates started in 2014.
BOTTOM: Change in

Mauna Loa 1950 Eruption...
September 17, 2015

Mauna Loa 1950 Eruption

On June 1, 1950, a 2.4-km (1.5 mi) long fissure erupted high on Mauna Loa's Southwest Rift Zone at 9:04 p.m. Minutes later, the roar of lava fountains could be heard up to 24 km (15 mi) away. Within three hours, an ‘A‘ā lava flow crossed the main highway on the west coast of the Island of Hawai‘i and inundated the village of Pahoehoe (all villagers reached safety unharmed

A little red bird being handled by scientist
August 31, 2015

Iiwi banded at Hakalau 1

Adult Iiwi being banded at Hakalau Forest National Wildlife Refuge, Hawaii

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June 26, 2003

An unprecedented experiment to track the travel route of microscopic coral larvae will be conducted off the coast of Maui from June 29 to July 5 by the U.S. Geological Survey (USGS), the University of Hawai‘i, the Hawaiian Division of Aquatic Resources, the Maui Ocean Center, and the University of Washington.

Eruption cloud, Anatahan Volcano
June 26, 2003

The eruption of Anatahan Volcano in the Commonwealth of the Northern Mariana Islands (CNMI) continues. It has generated much interest in the volcanologic community and among the residents of Saipan and Guam. It has, unfortunately, also generated exaggerated accounts on the Internet.

Closeup of Lake Waiau. The white particles hugging the edges are remains of ice
June 19, 2003

Lake Waiau, at an altitude of 3,969 m (13,020 ft) atop Mauna Kea, is the only alpine lake in the Hawaiian island chain. It is thought to have formed at the end of the last glacial retreat, which in Hawai`i was almost complete by 15,000 years ago.

June 12, 2003

For the past couple of weeks, Kīlauea had presented us with a flurry of tiny earthquakes located at a shallow depth beneath the volcano's summit. The exact cause of this cataract of miniscule events is unknown, but one possibility that comes to mind is expanding gas bubbles trying to escape from the summit magma reservoir.

June 5, 2003

This week is the 91st anniversary of the largest eruption on earth since Krakatau exploded in 1883. We are also ending the 4th week of an ongoing eruption whose final size and violence are not yet known but which so far has been small. Each eruption took place along the margin of the Pacific plate, in the middle of which Hawai`i has formed.