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1975 Short-lived Eruption

Following 25 years of slumber, Mauna Loa awoke with a spectacular, but short-lived, eruption just before midnight on July 5, 1975. Lava fountains 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, activity in the caldera and on the Southwest Rift Zone ended, but lava fountaining continued along the Northeast Rift Zone until 7:30 p.m. on July 6, when all activity ceased.