Eruption dynamics of Hawaiian-style fountains: the case study of episode 1 of the Kīlauea Iki 1959 eruption
- 619 Downloads
Hawaiian eruptions are characterized by fountains of gas and ejecta, sustained for hours to days that reach tens to hundreds of meters in height. Quantitative analysis of the pyroclastic products from the 1959 eruption of Kīlauea Iki, Kīlauea volcano, Hawai‘i, provides insights into the processes occurring during typical Hawaiian fountaining activity. This short-lived but powerful eruption contained 17 fountaining episodes and produced a cone and tephra blanket as well as a lava lake that interacted with the vent and fountain during all but the first episode of the eruption, the focus of this paper. Microtextural analysis of Hawaiian fountaining products from this opening episode is used to infer vesiculation processes within the fountain and shallow conduit. Vesicle number densities for all clasts are high (106–107 cm−3). Post-fragmentation expansion of bubbles within the thermally-insulated fountain overprints the pre-fragmentation bubble populations, leading to a reduction in vesicle number density and increase in mean vesicle size. However, early quenched rims of some clasts, with vesicle number densities approaching 107 cm−3, are probably a valid approximation to magma conditions near fragmentation. The extent of clast evolution from low vesicle-to-melt ratio and corresponding high vesicle number density to higher vesicle-to-melt ratio and lower vesicle-number density corresponds to the length of residence time within the fountain.
KeywordsHawaiian fountaining Kīlauea Kīlauea Iki Vesicle size distribution Post-fragmentation expansion
We thank Julia Hammer, Gary Barnes, Jacopo Taddeucci, and an anonymous reviewer for their helpful feedback on this work prior to publication. The breadth of this data set was greatly helped by Maria Janebo’s diligent and thorough assistance with laboratory work. We are also very grateful to Thomas Shea for his invaluable MATLAB program, FOAMS. Thanks also to Lisa Swinnard and Penny Larin for their help with rocks and stratigraphical logs. This research was funded by NSF grants EAR-0709303 and OISE-0811838 and published under employment with IM Systems Group on contract at NOAA Pacific Services Center.
- Bertagnini A, Calvari S, Coltelli M, Landi P, Pompilio M, Scribano V (1990) The 1989 eruptive sequence. In: Barberi F, Bertagnini A, Landi P (eds) Mt. Etna: the 1989 eruption. Giardini, Pisa, pp 10–22Google Scholar
- Cashman KV, Mangan MT (1994) Physical aspects of magmatic degassing II: constraints on vesiculation processes from textural studies of eruptive products. In: Carroll MR, Holloway JR (eds) Volatiles in magmas. Reviews in mineralogy. Mineralogical Society of America, Fredricksberg, pp 447–478Google Scholar
- Eaton JP, Richter DH, Krivoy HL (1987) Cycling of magma between the summit reservoir and Kīlauea Iki lava lake during the 1959 eruption of Kīlauea volcano. In: Decker RW, Wright TL, Stauffer PH (eds) Volcanism in Hawai‘i. US Geol Sury Prof Pap, 1350: 1307–1334Google Scholar
- Heliker C, Mattox TN (2003) The first two decades of the Pu‘u ‘Ō‘ō-Kupaianaha eruption: chronology and selected bibliography, the Pu‘u ‘Ō‘ō-Kupaianaha eruption of Kīlauea volcano, Hawai‘i: the first 20 years. US Geol Sury Prof Pap 1676:1–27Google Scholar
- Murata KJ, Richter DH (1966) Chemistry of the lavas of the 1959–60 eruption of Kīlauea Volcano, Hawai‘i. In: The 1959–60 eruption of Kīlauea volcano, Hawai‘i. US Geol Sury Prof Pap, 537-A:A1–A26Google Scholar
- Richter DH, Eaton JP, Murata KJ, Ault WU, Krivoy HL (1970) Chronological narrative of the 1959–60 eruption of Kīlauea volcano, Hawai‘i. In: The 1959–60 eruption of Kīlauea volcano, Hawai‘i. US Geol Sury Prof Pap, 537-E:E1–E73Google Scholar
- Swanson DA, Duffield WA, Jackson DB, Peterson DW (1979) Chronological narrative of the 1969–71 Mauna Ulu eruption of Kīlauea volcano, Hawai‘i. US Geol Sury Prof Pap 1056:1–55Google Scholar