Start of the Eruption: 1983

Map of topographic, volcanic, and cultural features of the East Rift Zone and south flank of Kilauea volcano. Modified from Clague and Heliker (1992).

1. Kilauea caldera 6. Kamoamoa11. Highway 130
2. Chain of Craters Road7. Wahaula12. Highway 11
3. Puu Oo8. Lae Apuki13. Pauahi Crater
4. Kupaianaha9. Kapaahu14. Mauna Ulu
5. Royal Gardens10. Kalapana

On the early morning of January 2, 1983, the summit of Kilauea began to deflate, and the number and size of earthquakes increased in the volcano's east rift zone. The earthquakes started near Mauna Ulu and migrated down right to Napau Crater and Puu Kamoamoa.

Geologists interpreted the swarm of earthquakes to be a result of magma breaking rock as it is forced into the rift zone and then moved towards the surface.

Shortly after midnight on January 3, 1983, lava was sighted near Napau Crater. Seismic instruments also recorded an increase in the amount of harmonic tremor, the earthquake pattern that indicates magma movement and eruption. Over the next nine hours, a discontinuous line of the eruptive fissures extended 4 miles (6 km) down the rift (see above photo). Near the end of this activity the eruption became concentrated in the vicinity of Puu Kamoamoa. Subsequent eruptive activity was located at several different vents and varied in duration from less than an hour to almost one day. The photograph shows a line of fissures about 0.9 km long. Lava flows are extending to the north and south. View is to the southeast. Photograph by J.D. Griggs, U.S. Geological Survey, January 3, 1983, 7:29 a.m.

Geologists from the U.S. Geological Survey's Hawaiian Volcano Observatory monitored the eruption in many ways. This photo shows a geologist approaching a fissure to collect a sample of spatter for chemical analysis. Photograph by J.D. Griggs, U.S. Geological Survey, January 7, 1983.

Change to Central-Vent Eruptions

Episode 2 of the eruption began on February 10, and continued to March 4. The primary eruption site was then a central vent, rather than a series of fissures. This vent was called the 1123 vent, a name designated at the time of its first eruptive activity. Lava fountains from this vent reached a height of 260 ft (80 m). Episode 3 (March 21 to April 9, 1983) was also located at the 1123 vent. This episode had two lava fountains, one of which attained a height of 650 ft (200 m) near the end of the episode. The second, lower fountain, fed an aa lava flow that extended 4.4 miles (7 km) to the southeast and reached the Royal Gardens subdivision. Photograph by J.P. Lockwood, U.S. Geological Survey, April 3, 1983.

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