# Volcano Watch (no. 2)

Release Date:

Volcano Watch is a weekly article and activity update written by U.S. Geological Survey Hawaiian Volcano Observatory scientists and colleagues.

Map shows the location of lava flows from Puʻu ʻŌʻō (unshaded), and Kūpaianaha (dark shaded), and Friday's fissure eruption (light shading) on Kīlauea's East Rift Zone. The inset shows the area of the enlarged flow field map and the locations and magnitudes of all felt earthquakes for the past week. (Public domain.)

The U.S. Geological Survey's Hawaiian Volcano Observatory reports that Kīlauea Volcano continues to erupt from the Kupaianaha vent on the East Rift Zone and from a new fissure that opened Friday morning between Puu Oo and Kupaianaha. Flows are still active along the western edge of the Kupaianaha flow field near the 700-, 200-, and 100-foot levels and to the southwest and northwest of Kupaianaha from the new fissure.

The new eruptive activity on Friday morning began with a short burst of shallow volcanic tremor beneath the summit about 2:00 a.m. Small earthquakes then became frequent beneath the summit and upper East Rift zone. The summit began to deflate about 4:30 a.m. as magma moved into the upper East Rift. At 4:50 a.m. we had a report of glow just downrift from Puu Oo. Commercial helicopters reported that the pond at Puu Oo had drained and that a fissure eruption was underway at 7:45 a.m. The fissure eruption was continuing [at the time of this writing] yesterday afternoon, with flows headed both northeast and southeast from the eruptive fissure. Most of the lava is ponding between Puu Oo and Kupaianaha.

Until Friday morning, an active lava pond within the Puu Oo vent was about 175 feet below the lowest point on the rim of the cone. The level of the lava pond had slowly decreased over the past two months from a highest level about 100 feet below the rim. Before Friday, occasional degassing episodes sent spatter to the height of the rim. On Friday morning, the active pond within Puu Oo drained an additional 100 feet.

During a typical week, 300 to 400 located earthquakes occur beneath the Island of Hawai`i, as recorded on the Hawaiian Volcano Observatory seismic network. However, only a few have magnitudes greater than 3.0, roughly the threshold for felt earthquakes. This past week the only earthquake with magnitude greater than 3.0 was located on the south flank of Kīlauea (see map inset).

See above.