The Location, History, and Current Activity of Kilauea in Hawaii

Kīlauea, a basaltic shield volcano on the Big Island of Hawaii, has been an active location for volcanism since the early 1800s, with monitoring beginning in 1924 at Halema‘uma‘u Crater, site of an active lava lake. The Lower East Rift Zone(LERZ), an area of extension along the southeastern part of the Big Island, first had an eruption in 1955 at Lower Puna. In the LERZ, Pu’u ‘Ō‘ō vent has historically been the most active, producing numerous lava flows that reached the sea. Beginning in 1983, fissures appeared as part of an eruption, which eventually led to building of a lava cone. Effusive volcanic activity continued in this area for several years, forming a shield, Kupaianaha, from 1986 to 1992. Following the building of Kupaianaha, numerous collapse events occurred at the Pu’u ‘Ō‘ō crater, widening it and forming the location for a lava lake. The continued filling and draining of the lava lake, continued, leading up to the large eruption that began in May, 2018 and ceased in mid-August. During this eruption period, 24 fissures opened along the LERZ, expelling lava through fountaining and flows. Many of the flows reached the coast of the island and began to accumulate, forming a lava delta on the southeast edge, which added approximately 320 acres to the island’s area. The fissures were transient and closed and reopened as magma migrated through the crust. The opening of fissures changes was linked to the draining and refilling of the lava lake at Halemaumau crater. The crater experienced numerous collapse events throughout the few months of the eruption, dropping ~600 m in elevation. Coincident with the collapses, was a pattern of seismicity that repeated at approximately 23 hour intervals, characterized by magnitude 4.4-5.5 earthquakes, as well as explosive eruptions that reached 300-600m. This eruption also had other hazards associated with it besides seismicity, fissures, and lava flows, such as Laze and Vog. Laze (lava haze) is volcanic gas and hot ash expelled from the volcano and is extremely dangerous due to its acidic nature, and Vog (volcanic smog) consists of gas and particles ejected from the volcano in which visibility is decreased in both cases. The style and duration of volcanism at Kilauea in 2018 was unprecedented, and volcanologists are attempting to understand the changes in the magma plumbing system and what that may mean for future activity.