It is estimated that Hualālai rose above sea level about 300,000 years ago. Despite maintaining a very low level of activity since its last eruption in 1801, and having been unusually inactive for the past 2,000 years, Hualālai is still considered active and is expected to erupt again sometime in the next century. We cannot say when Hualālai will erupt, but we can offer clues as to the nature of its next eruption.
Hualalai
erupts much less frequently than its neighbors, with centuries more than years or decades separating eruptions.The most recent documented activity was a seismic swarm in 1929, which probably corresponded to a magma intrusion into the volcano. Its most recent eruption occurred in 1800-01, and lava flows erupted from 1800-01 underlie almost the entire Ellison Onizuka Kona International Airport in Keahole. Future Hualalai eruptions may pose a direct threat to Kailua-Kona and surrounding communities. Hualalai, the third of Hawaii's active shield volcanoes, is located northwest and west of its giant neighbors Mauna Loa and Mauna Kea.
Hualalai volcano last erupted between 1800-1801, when it produced lava flows from 5 fissure vents that reached the sea and buried Hawaiian villages. The Hualalai began to erupt about 800,000 years ago and broke the surface of the sea about 300,000 years ago. The volcano has 3 rift zones, the most prominent being the northwest rift, which is about 40 km long and continues in the sea to a depth of 3000 m. Although studies indicate that Haleakalā will erupt again, the volcano is currently inactive.
The volcano is currently being monitored as a moderate priority according to the National Volcano Early Warning System. The highest priority volcanoes in Hawaii are Kilauea and Mauna Loa because both are active volcanoes. Compared to Kilauea and Mauna Loa, Hualalai poses a different challenge in monitoring changes in activity. For residents of the Kona area, keep in mind that Hualalai hasn't erupted since 1801; Mauna Loa is considered active but hasn't erupted since 1984.It is approximately three-quarters of the area of the 1800-1801 eruption, and is the third largest known to Hualalai in terms of area covered.
Another geologically recent Hualalai eruption was the Wahapele eruption, which probably occurred sometime between 1200 and 1400 A.D. Hualalai, Mount Hualalai, Hualalai Mountain, or Hualalai Volcano: it's just one name, Hualalai. USGS Graphic This map shows the location of the Wahapele vent (star) and the lava flow (red) at Hualalai volcano. The source of this eruption was the Wahapele Crater, a vent on the southern flank of Hualalai at 1,540 meters (5,053 feet) high.