Volcano Watch — Unusual events of March-April 1868

On Friday, March 27, 1868, at 5:30 a.m., several whaling ships anchored in Kawaihae Harbor noticed a dense column of fume reflected by a bright light southwest of the summit of Mauna Loa. An eruption near Moku`aweoweo had taken place, lasting several hours before subsiding. Pele's hair had drifted down upon the residents of Ka`u and South Kona, indicating the presence of lava fountains above.

In near synchrony with its larger neighbor, Kīlauea Volcano began to shake at 10:00 a.m. the next day with a series of earthquakes that increased in intensity for several days. Cracks appeared around the summit of Kīlauea; the level of the lava lake in Halema`uma`u fluctuated rapidly. Stone walls collapsed, houses shook, and trees vibrated.

The largest historic earthquake in the Hawaiian Islands happened at 3:40 p.m. on April 2. The earthquake had an estimated magnitude of 7.9. Clocks stopped on O`ahu. At Kohala, the shock was so strong that it stopped all of the engines at the Kohala Mill, including the 75-horsepower main engine. All over the Island of Hawai`i, the effects were felt as a large portion of the coastline from Honu`apo to Kapoho subsided 1.2 to 2.1 meters (4 to 7 feet).

Coastal villages were inundated by a huge tsunami, at places over 15 meters (50 feet) high. The coastal villages of `Apua, Keauhou, Punalu`u, Ninole, Kawa`a, Honu`apo and Ka`alualu were destroyed. There were five large waves in succession. The largest came first. A total of 75 people and numerous animals were swept out to sea and drowned.

Along with the coastal subsidence and tsunami, the earth at Kiolaka`a, near Wood Valley, broke loose and slid 300 meters (1,000 feet) down from the summit and southeast side of the hill onto the valley below, covering houses and trees. This event, known as the mud flow, buried people, horses, cattle, goats and sheep under a thick layer of mud. The mud flow was 5 km (3 miles) long, as wide as 1.5 km (1 mile), and varied in thickness from 1 meter (3 feet) to 27 meters (90 feet).

All stone walls and dwellings in Ka`u were flattened by the earthquake; people and animals were thrown down, and ground cracks appeared throughout Kīlauea and in the district of Ka`u. Landslides occurred island-wide, and plantation chimneys in the Hilo area fell down. Aftershocks almost as violent as the April 2 event hit at 12:20 a.m. and again at 12.45 a.m. on April 4.

At about 5:00 p.m. on April 7, a great crack opened along Mauna Loa's southwest rift zone above the Captain Robert Brown ranch in Kahuku. Lava gushed from the earth and flowed directly toward the ranch house. Captain Brown, his wife, and nine children ran for their lives as the molten flood engulfed their home. Within three hours, the flow reached the sea, a distance of 17 kilometers (10 miles) from the vent.

Volcano Activity Update

Eruptive activity of Kīlauea Volcano continued unabated during the past week. Lava is erupting from Pu`u `O`o and flowing through a network of tubes from the vent to the sea. Lava is entering the ocean near Kamokuna and enlarging the bench. Occasional phreatic activity was observed at the entry. The public is reminded that the ocean-entry area is extremely hazardous, with explosions accompanying unpredictable collapses of the new land. The steam clouds are highly acidic and laced with glass particles.

There were no earthquakes reported felt during the week ending on July 22, 1999.