Kilauea. Hawaii N, W; summit elev. 1,222 m. All times are local (= UTC -10 hours) Summary of highlights for

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1 Kilauea Hawaii N, W; summit elev. 1,222 m All times are local (= UTC -10 hours) Summary of highlights for The following is a concise summary of reports by the U.S. Geological Survey Hawaiian Volcano Observatory (HVO) on Kilauea volcano covering the 3 years Volcano highlights for 2009 were covered in BGVN 38:02. Figure 1 shows a map of the lava-flow field on Kilauea s east rift zone as of 26 July On this map some of the older lava flows are labeled with the years during which they were active. Other maps appearing in earlier Bulletin reports indicated important features such as Napau crater, Pu u O o. HVO posts both Daily and Weekly updates on Kilauea activity (at links provided in the Information Contacts section below).

2 Figure 1. Small-scale map showing Kilauea s east rift zone flow field as of 26 July The Peace Day flow, carried lava from the vent area to the ocean, and the inactive Kahauale a flow from early 2013, are light reddish orange and labeled The active flow called Kahauale a 2 flow N of Pu u O o, is shown in shades of red, with bright red showing expanded coverage since June Older lava flows are labeled with the years in which they were active. Flows during (episodes 1 48b) are shown in gray; during (episodes 48c 49) in pale yellow; during (episode 50 55) in tan; and during (episodes 58 60) in pale orange. The location of the Peace Day lava tube is shown by the yellow line, but where the tube crosses the coastal plain it has not been mapped. The interval between the contours depicting the topographic high at Pu u O o is 5 m. Courtesy of USGS/HVO. The Hawaiian Volcano Observatory (HVO) celebrated its centennial in January 2012 and the 30 th year of Kilauea s ongoing eruption, now active at its summit and east rift zone, on 3 January Orr and others (2012) summarized Kilauea s 30-year-long eruption, furnishing the following excerpt from the period in that report. Summary of Regarding this interval, Orr and others (2012) made the following comments. In January the tube system broke down [enabling lava to escape from the tube] and surface flows began moving toward the east, encroaching on the Kalapana area once again. Three more houses were destroyed between July 2010 and March 2011, when the surface flows faltered : History Repeats Itself. Pu u O o began to refill slowly during 2010, and by early March 2011, the crater floor was within 65 feet (20 meters) of the crater s east rim. On March 5, 2011, following rapid summit deflation and increased seismicity, the crater floor of Pu u O o collapsed. Within a few hours, it had dropped 380 feet (115 meters). Shortly thereafter, lava broke to the surface between Pu u O o and Napau Crater, marking the start of the Kamoamoa fissure eruption, which was active through March 9. Reminiscent of Kilauea s 1997 and 2007 East Rift Zone fissure eruptions, the Kamoamoa eruption cut the lava supply to the active tube, causing activity on the flow field to die. After 2 weeks of quiet, lava reappeared in Pu u O o on March 26, and a perched lava lake developed as the crater refilled. In late June, wholesale uplift of the crater floor raised the entire lava lake until its surface was higher than the eastern and western crater rims. Leaks from the ring fault bounding the uplifted area resulted in lava overflowing the crater for the first time since 2004, sending flows down the southwestern flank of Pu u O o. {Note that this is discussed further below.} On August 3, 2011, the crater floor of Pu u O o collapsed again when lava burst through Pu u O o s west flank, burying the western base of the cone in a massive flood of lava. The floor of the crater dropped 260 feet (80 meters), accompanied by the collapse of large slabs of rock from the crater walls into the resulting pit. The flow on the west side of Pu u O o diminished greatly after the first several hours but remained active until August 15. As in March, lava returned to Pu u O o within days of the August outbreak, but this time

3 the crater filled quickly. By September 10, lava had begun to overflow the crater again, with flows spilling toward the northeast and southwest. This activity ended on September 21, when the northeastern flank of the cone fractured and lava began pouring out. Confined to a shallow valley between older Pu u O o flow fields, lava turned again toward the volcano s S coast. In March 2012, lava flows destroyed another house the 214th since 1983 within the now-abandoned Royal Gardens subdivision {approximate location shown in figure 1}. Unlike past years, however, eruptive activity throughout 2012 was relatively weak. Lava flows were almost always active on the coastal flow field but failed to make significant forward progress. Finally, in late November, lava reached the coastline for the first time in nearly 11 months, forming a small and sporadic ocean entry. This marked the end to the longest period without an ocean entry since lava first reached the water in As the eruption enters its 31st year in 2013, it is showing no signs of stopping, despite the recent slow down in activity. What Kilauea Volcano has in store next remains to be seen. Although recent patterns suggest continued activity on the East Rift Zone, this could change abruptly. Even a return to Kilauea s more explosive past is possible (see USGS Fact Sheet , Kilauea an Explosive Volcano in Hawai i, available at {Swanson and others, 2011}). What is certain is that Kilauea will remain an active volcano for millennia to come. More details on events. HVO reporting disclosed events presented below in tables 1, 2, and 3, including a brief summary of events (table 1), a broad overview of the eruption during (table 2), and several of the notable collapses during (table 3). Table 1. Brief summary of events at Kilauea during the period Courtesy of various USGS/HVO reports (periodic, fact sheets, etc.). Date(s) Event 4 Jan 2010 Cessation of Waikupanaha ocean entry after 22 months 25 Jan-10 Mar 2010 Persistent flow through Royal Gardens and out onto the coastal plain Feb or Mar 2010 Small collapse of E wall Pu u O o crater rim 29 Apr-30 Nov 2010 New ocean entries of lava at Ki, Puhi-o-Kalaikini, and Ili ili May, Jul, and Aug 2010 May-Jun 2010 Portions of N rim of Pu u O o fall into crater Lava erupted on S wall and NE side of Pu u O o crater

4 Late July, 27 Nov 2010 Sep-Dec 2010 Nov 2010-Feb houses destroyed in Kalapana Gardens subdivision Eruption of vent on W edge of Pu u O o crater Increase in long-term inflation of Pu u O o crater 2011 East rift zone eruption episodes (see Table 2) Jan, early Feb 2011 Ocean entries at 2 previous areas, Puhi-o-Kalaikini and Ki 17 Feb 2011 House destroyed in Kalapana Gardens subdivision 5 Mar 2011 Beginning of eruption Episode 59 (see table 2); floor of Pu u O o crater began collapsing; new fissures opened between Napau Crater and Pu u O o 26 Mar 2011 Beginning of eruption Episode 60 (see table 2); lava filled collapse crater of Pu u O o and uplifted lake floor 24 July 2011 Lava flow from ring fracture along SW margins of Pu u O o crater 3 Aug 2011 Lava lake draining through from lower W flank of Pu u O o; lake completely drained within several hours, leaving a rubble-filled depression ~80 m below its precollapse level 20 Aug 2011 Beginning of eruption Episode 61; Pu u O o refilled and overflowed 21 Sep 2011 Lava broke through the upper E flank of the Pu u O o cone; Pu u O o crater subsided ~20 m; flow (Peace Day flow) resulted in a channelized a a flow to SW 22 Sep 2011 Channelized a a flow stalled; fissure and open channel crusted over by mid-oct Dec 2011 Flow reached ocean entry by evening 9 Dec Peace Day flow continued to be active Early 2012 Subsidence in Pu u O o crater continued; outgassing events on crater floor 2 Mar 2012 House in Royal Gardens subdivision destroyed

5 End of Aug 2012 Deflation phase led to lowering of lava lake beneath Pu u O o crater ; lava began erupting and filled in NW pit by Sep Table 2. An overview of the Kilauea East Rift Zone (ERZ) eruption during (eruption episodes 57-61) including (from left) episodes, dates, (approximate in some cases) vent locations, and estimated volume of erupted material. HVO subdivides 30-year-long Pu`u `O`o eruption into episodes. Each new episode denotes vigorous new eruptive activity either from a different vent or commencing after a pause or slowdown. Some episodes are well defined; others more arbitrary. The day and time of various episodes may vary slightly with different instrumentation. The dates in the table signify the duration of the episode or episodes. Courtesy of M. Patrick (USGS) and various USGS/HVO reports. Episode(s) Dates Vent location Est. volume (km 3 ) July Mar 2011 Crater fill and fissures E of Pu u O o Mar 2011 Kamoamoa fissures Mar-15 Aug Aug present Pu u O o overflows and W flank vent Pu u O o overflows and Peace Day flow Table 3. For Kilauea, a list containing several notable collapses and/or explosive events during Courtesy of various USGS/HVO reports and Matthew Patrick, USGS/HVO. Date Time (HST) Notes 11 Feb Collapse in vent; continuous lava lake started 26 Apr Collapse in vent; lava lake doubled in size 17 Jan Series of explosions 21 Jan Explosion 14 Feb Series of explosions

6 15 Feb Series of explosions 20 Feb Explosion 3 Mar Series of explosions 21 Dec Explosion 30-yr long eruption summary comments. Table 4 and figure 2 present general information about the total 30-yr eruption period. Table 4. Selected eruption statistics for the entire 30-year during 1983 to January Courtesy of Orr and others (2013) and various USGS/HVO reports. Feature Statistic Area covered km 2 New land on coast 2.02 km 2 Volume erupted (dense rock equivalent) ~4 km 3 Thickness along coast 10 to 35 m Pre-1983 area covered in km 2 Net total of land added to the island (Nov 1986 Dec 2012) Coastal highway covered by lava km km Structures destroyed 214 Pu u O o maximum height 255 m in 1987; 171 m in 2012 Pu u O o crater size m Satellite images. To provide a comparison, NASA Earth Observatory prepared both a natural-color satellite image from 6 June 2011 (figure 2a), and a black-and-white aerial photograph from 25 March 1977 (figure 2b). As the authors noted, the images both show the landscape surrounding Napau Crater and Pu u O o. Lava flows that are more than a century old are covered by a dense forest of ohia lehua and tree ferns forest (green in the 2011 image). Flows from eruptions in 1965, 1968, and 1969 are much lighter than the forest in the 1977 image, but difficult to differentiate from one another. By comparison, the 2011 image shows profound changes in the landscape.

7 Weathered lava from the initial Napau Crater vent is almost indistinguishable from the older (1968 and 1969) lavas that cover most of the crater floor. In January 1997, a fresh line of fissures opened within Napau Crater, erupting lava during Episode 54 of the Pu u O o- Kupaianaha eruption. Additional cracks and fissures split the earth between Napau Crater and Pu u O o in the March 2011 Kamoamoa Fissure Eruption (Episode 59), spreading black lava through the forest. Scorched forest appears reddish-brown along the edges of the lava flows. Since 9 March 2011, lava flows have originated from Pu u O o (figure 2a, upper right). A lava pond is visible within the crater, and a system of lava tubes carries molten rock underground to the southeast. Brown lavas surrounding the crater flowed directly from the lava pond.

8 Figure 2. Two images a natural-color satellite image from June 6, 2011 (A), and a black-andwhite aerial photograph from March 25, 1977 (B) show the landscape surrounding Napau Crater and Pu u O o. Lavas of different ages cover the surface. Lava flows that are more than a century old are covered by a dense forest (green in the 2011 image) of ohia lehua and tree ferns. Flows from eruptions in 1965, 1968, and 1969 are much lighter than the forest in the 1977 image, but difficult to differentiate from one another. The 2011 image shows dramatic changes in the landscape. Weathered lava from the initial Napau Crater vent is almost indistinguishable from the older (1968 and 1969) lavas that cover most of the crater floor. In January 1997, a fresh line of fissures opened within Napau Crater, erupting lava during episode 54 of the Pu u O o- Kupaianaha eruption. Additional cracks and fissures split the earth between Napau Crater and Pu u O o in the March 2011 Kamoamoa Fissure Eruption (Episode 59), spreading black lava through the forest. Scorched forest appears reddish-brown along the edges of the lava flows. Since 9 March 2011, lava flows have originated from Pu u O o (image upper right). A lava pond is visible within the crater, and a system of lava tubes carries molten rock underground to the southeast. Brown lavas surrounding the crater flowed directly from the lava pond. Images taken from Simmon (2012). Hawaiian names and nomenclature. According to Runyon (2006), The U.S. Board on Geographic Names (BGN) is responsible for establishing and maintaining uniform geographical name usage throughout all departments and agencies of the United States government. As such, the Board collects and promulgates every name that is considered official for Federal use. The official vehicle for promulgating these names and their locative attributes is the Geographic Names Information System (GNIS) < Until the 1990 s, it was also Federal policy to omit most diacritics and writing marks from placenames on Federal maps and documents. The few exceptions included the Spanish tilde and the French accent marks, but otherwise the special characters found in indigenous names were always dropped. In more recent years, however, the BGN has amended its policy to permit the inclusion of such marks, thus more accurately reflecting the true representation of the native language. An example of this has been the addition of the glottal stop (okina) and macron (kahako) to placenames of Hawaiian origin, which prior to 1995 had always been omitted. The BGN staff, under the direction and guidance of the Hawaii State Geographic Names Authority, has been restoring systemically these marks to each Hawaiian name listed in GNIS. GVP will strive to conform to GNIS nomenclature. It remains a technological challenge, but a goal. References: Orr, T., Heliker, C., and Patrick, M., 2012, The ongoing Pu u O o eruption of Kilauea Volcano, Hawai i 30 years of eruptive activity, U.S. Geological Survey Fact Sheet , 6 p. (URL: accessed 15 August 2013). Runyon, J., 2006, U.S. Board on Geographic Names Collection and Dissemination of Indigenous Names (United Nations Group of Experts on Geographical Names, Working Paper No. 82, Twenty-third Session, Vienna, 28 March 4 April 2006). (URL:

9 Simmon, R., 2012, 30th Anniversary of the Pu u O o Eruption on Kilauea, NASA Earth Observatory (URL: Swanson, D., Fiske, D., Rose, T., Houghton, B, and Mastin, L., 2011, Kïlauea an explosive volcano in Hawai i, U.S. Geological Survey Fact Sheet , 4 p (URL: accessed 15 August 2013). USGS/HVO April 2012, 14 p. (URL: accessed 15 August 2013). USGS/HVO, 2013, Maps, July 26, Kilauea, Kilauea s east rift zone flow field, web site (URL: accessed 15 August 2013). Geologic Summary. Kilauea volcano, which overlaps the east flank of the massive Mauna Loa shield volcano, has been Hawaii's most active volcano during historical time. Eruptions of Kilauea are prominent in Polynesian legends; written documentation extending back to only 1820 records frequent summit and flank lava flow eruptions that were interspersed with periods of long-term lava lake activity that lasted until 1924 at Halemaumau crater, within the summit caldera. The 3 x 5 km caldera was formed in several stages about 1500 years ago and during the 18th century; eruptions have also originated from the lengthy E and SW rift zones, which extend to the sea on both sides of the volcano. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1,100 years old; 70% of the volcano's surface is younger than 600 years. A long-term eruption from the E rift zone that began in 1983 has produced lava flows covering more than 100 sq km, destroying nearly 200 houses and adding new coastline to the island. Information Contact: Hawaiian Volcano Observatory (HVO), U.S. Geological Survey, PO Box 51, Hawai'i National Park, HI 96718, USA (URL: Daily updates, and Weekly updates,