![]() ![]() This was similar in character to the tilt events of recent months, starting with fairly rapid deflation, followed by a similar rate and magnitude of inflation. One of the largest of these deformations took place on 25-26 November and resulted in about 3 microradians of tilt at UWE, and 5 microradians at POC. The tiltmeter record at Kīlauea summit (UWE) and Pu`u `O`o (POC) showed numerous correlated tilt changes, with a short time delay between UWE and POC stations and larger magnitude delays at POC (figure 172). Most of the events on 25 January appeared to be of the SPC variety. Geological Survey's Hawaiian Volcano Observatory.Ī minor peak in seismicity occurred in later January, during the two days before and after the 25 January inflation-deflation event. A time series of Kīlauea's daily earthquakes (SPC, LPC-A, and possibly LPC-C types) registered at the summit during October 2004 through January 2005. Tremor episodes were rare or absent.įigure 171. In addition, small-magnitude deeper earthquakes, designated as long-period earthquakes originating at depths over 5 km, may have also registered within the summit caldera to appear on the plot, although they would be expected to contain a lower dominant frequency of oscillation than the LPC-A earthquakes. The similar frequency content of these two kinds of earthquakes make them difficult to distinguish on the drum record. Scientists combined the counts for two shallow (0-5 km deep) earthquake types, those designated by HVO as short-period summit or short-period caldera (SPC) and those designated as shallow, long-period (long-period caldera A, LPC-A) earthquakes. To obtain this plot, a daily event count was extrapolated from a representative part of the North Pit (NPT) seismogram. Nearly all of these earthquakes were too small to catalog. Elevated activity began on 16 November, peaking at over 2,000 events a day by late November (figure 171). After seven months of relative quiescence renewed seismicity and numerous small long-period (LP) events again became visible in November 2004 on the North Pit seismogram. The W branch of the PKK lava flow once supplied lava to Lae'apuki (an E branch of the W arm), but later also began feeding the West Highcastle ocean entry (the W branch of the W arm, figure 11). The large E arm of the PKK lava flow fed the larger Ka`ili`ili entry. In contrast, lava from the E and W arms of the PKK flow began to enter the ocean on 31 January. The middle arm of the PKK flow was comparatively small, and it failed to reach the ocean during this reporting interval it remained high on Pulama pali. By 2 February 2005 the PKK flow had entered the sea at West Highcastle, Lae'apuki, and Ka`ili`ili (figure 11).ĭuring January 2005, surface lava was visible along the three main arms of the PKK flow as they advanced downslope towards the coast (figure11). The PKK flow originated from two vents ~ 250 m S of the base of Pu `u `O`o. New vents opened at the southern base of Pu`u `O`o on 19 January 2004 and fed the Martin Luther King (MLK) flows (figure 11). The flow moderated during the second half of December with only several areas of visible surface lava apparent on the Pulama pali fault scarp and on the coast. By 13 December lava again entered the sea at the East Lae'apuki delta. Activity resumed during the second week along all areas of the PKK flow from high on the Pulama pali fault scarp. This flow stagnated early in September 2004, and the Mother's Day tube ceased carrying lava late in 2004.ĭuring the first week in December 2004, the lava flow at Lae'apuki abated. The Banana flow developed from breakouts when lava escaped from the confines of the Mother's Day lava tube, emerging near the former Banana Tree kipuka. This was the first time lava entered the sea since the Banana lava flow ceased in early August 2004. The PKK flow has been continuously active since 26 July 2004, and lava continued to enter the sea through 26 November 2004. ![]() On 4 November 2004 lava from the Prince Kuhio Kalaniana `ole (PKK) flow entered the sea, forming a new delta seaward of the E end of the old Lae'apuki delta. Geological Survey's Hawaiian Volcano Observatory. Kīlauea lava flows erupted during activity from 1983-2 February 2005 of Pu`u `O`o and Kupaianaha.
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