The Hawaiian Islands are the surface expression of some of the most dynamic and continuous volcanism on Earth. This archipelago is built upon a continuous, deep-seated source of heat, resulting in an ever-changing landscape. New land is constantly being formed by effusive lava flows, making persistent volcanic activity a defining feature of the region.
The Most Recent Eruption Event
The most recent formal eruption occurred at Kīlauea, the most active volcano on the Island of Hawaiʻi. Kīlauea has been in an episodic eruptive phase since December 2024, with activity confined to the summit region within Halemaʻumaʻu crater. The latest distinct event, Episode 39, took place in December 2025, lasting nearly six hours of sustained lava fountaining.
This eruptive style involves high-volume, short-duration bursts from multiple vents on the crater floor. During the December episode, lava fountains reached estimated heights of up to 1,400 feet from the south vent and 900 feet from the north vent. These fountains created significant convective plumes containing volcanic gas, ash, and volcanic glass shards known as Pele’s hair.
The lava flows were entirely contained within the boundaries of the summit caldera. This kept the activity away from residential areas or public infrastructure, unlike Kīlauea’s 2018 eruption. The current phase is characterized by intense fountaining followed by pauses lasting several days or weeks, as the system undergoes re-inflation.
Hawaii’s Currently Active Volcanoes
The Hawaiian Islands host six volcanoes currently classified as active, meaning they have erupted within the last 10,000 years. Four active volcanoes are located on the Island of Hawaiʻi (Big Island): Kīlauea, Mauna Loa, Hualālai, and Mauna Kea. Haleakalā on Maui is also active, along with the submarine Kamaʻehuakanaloa (formerly Lōʻihi Seamount) off the Big Island’s south coast.
Kīlauea is the youngest and most frequently erupting shield volcano, while Mauna Loa is the largest active volcano on Earth by volume. Mauna Loa last erupted in November 2022, ending a 38-year quiet period and sending lava flows toward the Daniel K. Inouye Highway. Hualālai, which overlooks the Kona coast, last erupted in 1801, and its eruption frequency is much lower.
Mauna Kea last erupted about 4,000 years ago, placing it within the definition of an active volcano. Volcanoes that have not erupted in the last 10,000 years are considered extinct, such as Kohala, the oldest volcano on the Big Island. Haleakalā, the single active volcano on Maui, last erupted between 400 and 600 years ago, and scientists anticipate future eruptions.
Understanding the Hawaiian Hotspot
The volcanic activity in Hawaii is driven by the Hawaiian Hotspot, a persistent plume of heat and molten rock (magma). This plume rises from deep within the Earth’s mantle, far from any tectonic plate boundary. The heat source itself is thought to be relatively stationary over geological time.
The Pacific Plate, which forms the ocean floor beneath the islands, constantly moves in a northwesterly direction. As the plate drifts over the fixed hotspot, the magma plume punches through the crust, creating volcanoes. The active volcanoes are located directly over or immediately southeast of the plume.
As the plate carries the newly formed volcano away from the hotspot, the magma supply is cut off. The volcano becomes dormant, then extinct, and begins to erode. This process, ongoing for at least 70 million years, created the long chain of islands and submerged seamounts across the Pacific.