Kilauea, Hawaii
- Pu'u O'o on October 3, 1997
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- September 17, 1999
- On September 12, a swarm of small earthquakes
and volcanic tremor began at Kilauea Volcano. The largest earthquake
in this episode occurred beneath Kilauea's south flank, near Pu'u O'o.
The earthquake was approximately magnitude 3.7. Accompanying the earthquake
swarm was deflation of the summit area. The crater floor of Pu'u O'o
collapsed. The flow of lava through the tube to the coast was weak and
sluggish.
- January 15, 1998
- There was a rapid inflation of the summit
of Kilauea beginning on the evening of January 14. Warnings went out
about a possible eruption. The summit deflated two hours later. Several
lava flows did reach the surface from the vents of Pu'u O'o during this
period. Most of this lava was confined to old flow fields, but some
lava did enter forested areas, burning vegetation in its path.
- October 21, 1997
- Lava began flowing from the vent inside
Pu'u 'O'o on October 18. Lava then overflowed repeatedly until the evening
of October 19. The vent is still erupting vigorously. The glow from
this vent can be seen at night from as far as 28 miles (45 km) away
from the volcano. Lava continues to enter the sea at Waha'ula and East
Kamokuna.
Close-up of the Pu'u O'o vent, October
3, 1997
- September 29, 1997
- Throughout September, lava has been erupting
from vents in the area of Pu'u O'o and flowing through lava tubes to
the sea. Lava has flown into the sea and built lava benches at two locations.
These benches are very unstable. They can and often have collapsed into
the sea. Small explosions at one of the points where lava enters the
sea are building a small cone.
Close-up of the Pu'u O'o vent, October 3, 1997
- August 12, 1997
The Wahaula Heiau temple before
it was destroyed.
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- Lava consumed the 700-year-old Wahaula
Heiau temple, considered by some to be the most sacred of Hawaiian temples.
Lava flowed over the 4-foot high walls and continued on to the ocean.
In both 1989 and 1990, lava crept near the temple but was diverted around
it. Since January, 1983, Kilauea has produced more than 1 billion cubic
yards of lava, adding 60 acres to the island.
- More for August 12, 1997
- Sarah Sherman and Andy Harris were able
to observe Pu`u `O`o and the active tube system for 3/4 of an hour on
Tuesday 12 August from the air. During this time Pu'u 'O'o was the location
of another over-spill event. At ~1:00 pm when we arrived at Pu`u `O`o
activity was restricted to a vigorously convecting 50-70 m wide kidney
shaped lava lake on the the western floor of Pu`u `O`o. Lava was welling
up vigorously on the western side of this lake, moving west to east
across the lake and pouring into a 30 x 30 m brighly incandescent hole.
The constantly churning lake surface was almost entirely incandescent.
- The tube system leading south to the
coast was marked by numerous (20-40?) active skylights. The ocean entry
which was witnessed begining at 3:00 am on Monday 11 August was still
active and had already built a bench which extended seawards ~30 m along
a 150-250 m length of coast. No surface flows were apparent inland of
the entry, and although filled by lava, the rectangular shape of the
Waha'ula Heiau was still evident. A second area of active sheet flows
had also been observed on Sunday and Monday, which at this time had
been much less vigorous and slower moving than the Heiau flow and was
still around half a mile from the sea. By the time of the 12 August
overflight this flow had also reached the sea and had built a bench
of similar dimensions to the Heiau entry around 1/2 a mile to the west
of the Heiau entry.
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- On returning to Pu`u `O`o at ~1:30 minor
fountaining and spattering were observed from cracks in the solid lava
surface of the main eastern part of the Pu`u `O`o floor. Within 5 minutes
the 30x30m hole into which lava had been pouring rapidly began to fill.
Within two minutes the hole was full and the kidney shaped lava lake
was overflowing vigorously down a spillway onto the eastern portion
of the Pu`u `O`o crater. The flood was fast moving, and ~5 m high standing
waves were evident in the spillway. Given that the lava took 2-3 minutes
to extend ~400 m to the eastern edge of the crater floor this gives
speeds of ~2-3 meters per second over a roughly horizontal surface.
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- We left before the main crater had filled,
however, radio traffic indicated that lava overflowed out of the E part
of the crater onto the Pu'u 'O'o flanks about 15 minutes after the intra-crater
kidney shaped pond began to overflow.
- Given that this necessitated a rise in
level of 2-4 m over a 90,000-250,000 square-meter area, this gives effusion
rates of 200-1100 cubic meters per second. Radio traffic indicated that
overflow onto the flank had stopped within 2-3 minutes and drainage
(presumably into the 30x30 m hole) was again occurring.
- August 4, 1997
- Lava at Kilauea is no longer flowing
into the ocean. In the evening of August 4, a large amount of lava began
to flow from a point about 1/4 of the way up Pulama Pali, and shortly
there after, lava stopped flowing into the ocean. Instead, it is producing
large flows on the coastal plain.
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