Volcano Watch

Halemaʻumaʻu crater has undergone repeated changes during the past two centuries. Prior to 1924, the size and shape of the Halemaʻumaʻu lava lake...

It’s hard to believe that the “Volcano Watch” weekly article and volcano activity update started 30 years ago. On November 3, 1991, the USGS Hawaiian...

Olivine crystals—the beautiful green mineral common in Hawaiian lavas—record when and where magmas move inside Hawaiian volcanoes before they erupt...

Volcanoes commonly give us clues that they are going to erupt. Before an eruption, gas, magma, and other fluids move below the surface of a volcano...

The rapid onset of the current summit eruption sent USGS Hawaiian Volcano Observatory field crews running to grab their gear and head for the rim of...

The recent eruption on La Palma, in the Canary Islands, has stimulated speculation that the volcano might collapse, creating a tsunami that would...

The magnitude-6.2 earthquake that occurred on Sunday, October 10 at 11:49 a.m. HST, originated just south of the Island of Hawai‘i. The large...

The past year has seen fluctuating lava lakes, ephemeral lava fountains, craggy spires, and drifting “islands” reminiscent of pre-1924 Halemaʻumaʻu...

Kīlauea volcano is erupting again. Wednesday afternoon, lava returned to Kīlauea's summit within Hawaiʻi Volcanoes National Park after a 4-month...

The Pacific is home to dozens of active volcanic systems including the massive Hawaiian shield volcanoes Kīlauea and Mauna Loa. Most basaltic shield...

Most residents of the Island of Hawaiʻi live on one of four potentially active volcanoes and probably have wondered about the threat of lava flows at...

Large quantities of volcanic gases, such as carbon dioxide (CO2), sulfur dioxide (SO2), and hydrogen sulfide (H2S), are released into the atmosphere...

We know that when a volcano erupts, molten red rock makes it to the surface, while during an intrusion it doesn’t. The difference between the two...

Late Monday afternoon, earthquake activity picked up at Kīlauea’s summit.  At about 1:30 a.m. HST on Tuesday, that activity intensified, and it became...

The 2018 lower East Rift Zone and 35-year-long Puʻuʻōʻō eruptions of Kīlauea had large impacts on the Puna District. Many residents were deeply...

More people were probably killed by the 1790 eruption of Kīlauea than by any other eruption in what is now the United States. Several hundred men...

Geologists at the USGS Hawaiian Volcano Observatory (HVO) had their mobile phones buzzing this past week with automated alert messages, notifying them...

This week marks the second anniversary of the appearance of water in Kīlauea’s Halema‘uma‘u crater, so it seems timely to discuss the water lake’s...

Many people living in the Hawaiian Islands are accustomed to feeling occasional earthquakes since the State of Hawaii is one of the most seismically...

The most recent page in Mauna Loa’s eruptive history was written in 1984. The eruption began in March of 1984, about a decade after the 1975 summit...