KILAUEA ERUPTION CONTINUES!
This update current as of August 8, 1997[Eruption updates are posted approximately every two weeks. More frequent updates will accompany drastic changes in activity or increased threat to residential areas.]
[Previous eruption updates may be accessed through our archive index.]
For readers familiar with events of the past few months, recent changes include:
The 55th episode of Kilauea's 14.5-year-long east rift zone eruption continues. This episode, which began February 24, 1997, has been characterized by shifting vent locations on the west and southwest flanks of Pu`u `O`o cone, rapid enlargement of the episode 50-55 lava shield, and intermittent activity inside the Pu`u `O`o crater.
In the past three weeks, eruptive activity has been focused at three main vents:
The crater cone intermittently produced large flows that commonly drained through a hole near the center of the crater. When this happened, only a small volume of lava entered the pond located on the eastern half of the crater floor. Periodically, the drainhole became blocked, causing the pond to fill and overflow the crater rim. On July 19 and 29 and August 4, lava in the crater rose until it overtopped the gap in the west wall of the cone. During the first of these events (July 19), the pond also briefly overflowed through two spillways on the southeast rim of the crater. None of the overflows through the west gap lasted more than three hours; within that time, the pond has always drained, interrupting the overflow process.
The second of the active vents, the mini-shield, erupts intermittently and has produced only short flows that extend no more than 30 m from the vent, contributing to the small shield it has constructed.
The third vent, south shield, has been the prolific producer of flows that mantle the flow field. All large flows of the last three weeks originated at the south shield vent. From July 12-29, a tube-fed flow from this vent entered the ocean at the East Kamokuna entry in Hawaii Volcanoes National Park. This flow built a lava bench approximately 350 m long (parallel to the shoreline) by 60 m wide. The ocean entry was marked by the usual large billowing steam plume and by mild steam explosions, which hurled spatter a short distance onshore, building two small littoral cones.
Beginning about July 18, another flow from the south shield followed a more easterly course across the 1983-1986 'a'a field. By July 26, this flow was headed toward the upper edge of the Royal Gardens subdivision, and on July 28 the flow was burning into the edge of the forest 1.6 km above the subdivision. This flow has since ceased.
The south shield shut down early in the morning of July 29. The lava tubes within the Royal Gardens flow and the ocean entry flow were empty by midday. The ocean entry stopped except for a trickle of lava from the draining tube. This was not an eruptive pause for episode 55, however, because the Pu`u `O`o crater cone remained active.
The south shield resumed erupting that night, July 29. By the morning of the 30th, lava had reoccupied the upper reaches of the tube leading to the ocean, and breakouts from the tube formed channeled 'a'a flows on the upper slopes of Pulama pali, the steep fault scarp that rises above the coastal plain. The new surface flows followed the course of the earlier July flows, and within two days the tube was reoccupied down to the coastal plain.
Lava reached the ocean at the East Kamokuna entry on August 4, by way of a western lobe of new lava. This same flow has an eastern lobe that branches at the foot of Pulama pali. The eastern lobe advanced to within 800 m of Waha`ula Heiau, a 700-year-old, rock-walled structure 450 m east of the current ocean entry. For part of its length the flow parallels the north-trending segment of the four-wheel-drive access road to Royal Gardens subdivison. The flow lies about 100 m west of the road.
Eruption-viewing opportunities change constantly, so those readers planning a visit to the volcano should contact the National Park for the most current information.
This map current as of August 4, 1997
More about vent geography?
Updated: 31 March 1998