Bulletin of Volcanology

, Volume 54, Issue 5, pp 361–384 | Cite as

Differentiation and magma mixing on Kilauea's east rift zone

A further look at the eruptions of 1955 and 1960. Part I. The late 1955 lavas
  • Rosalind Tuthill Helz
  • Thomas L Wright


The lavas of the 1955 east rift eruption of Kilauea Volcano have been the object of considerable petrologic interest for two reasons. First, the early 1955 lavas are among the most differentiated ever erupted at Kilauea, and second, the petrographic character and chemical composition of the lava being erupted changed significantly during the eruption. This shift, from more differentiated (MgO=5.0–5.7%) to more magnesian (MgO=6.2–6.8%) lava, has been variously interpreted, as either due to systematic excavation of a zoned, differentiated magma body, or to invasion of the differentiated magma by more primitive magma, followed by rapid mixing and eruption of the resulting hybrid magmas. Petrologic examination of several nearvent spatter samples of the late 1955 lavas shows abundant evidence for magma mixing, including resorbed and/or reversely zoned crystals of olivine, augite and plagioclase. In addition, the compositional ranges of olivine, plagioclase and groundmass sulfide are very large, implying that the assemblages are hybrid. Core compositions of olivine phenocrysts range from Fo85 to Fo77. The most magnesian olivines in these samples must have originally crystallized from a melt containing 8.0–8.5% MgO, which is distinctly more magnesian than the bulk composition of the late 1955 lavas. The majorelement and trace-element data are either permissive or supportive of a hybrid origin for the late 1955 lavas. In particular, the compositional trends of the 1955 lavas on plots of CaO vs MgO, and the virtual invariance of Al2O3 and Sr in these plagioclase-phyric lavas are more easily explained by magma mixing than by fractionation. The pattern of internal disequilibrium/re-equilibration in the late 1955 spatter samples is consistent with reintrusion and mixing having occurred at least twice, during the latter part of the 1955 eruption. Plagioclase zonation preserves possible evidence for additional, earlier reintrusion events. Least-squares modelling the mixing of early 1955 bulk compositions with various summit lavas±olivine pick the 1952 summit lava as most like the primitive component. The results also indicate the primitive component had MgO=7.5–8.0%, corresponding to liquidus temperatures of 1165–1175°C. The absence of Fe-Ti oxide phenocrysts in the late 1955 lavas implies that the cooler component of the hybrid had T>1110°C. Thus the thermal contrast between the two components may have been as much as 55–65°C, sufficient to produce the conspicuous disequilibrium effects visible in the spatter samples.


Bulk Composition Rift Zone Olivine Phenocryst Primitive Magma Cool Component 
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  1. Abbey S (1983) Studies in “Standard Samples” of silicate rocks and minerals 1969–1982. Geol Surv Canada Pap 83-15, 114 pGoogle Scholar
  2. Anderson AT, Wright TL (1972) Phenocrysts and glass inclusions and their bearing on oxidation and mixing of basaltic magmas, Kilauea volcano, Hawaii. Am Mineral 57:188–216Google Scholar
  3. Bowen NL (1928) The evolution of the igneous rocks. Princeton University Press, Princeton, NJGoogle Scholar
  4. Bruggman P (1988) Procedures and techniques for the analysis of rock powders using the Kevex 0700 spectrometer. Administrative Report, 20 ppGoogle Scholar
  5. Desborough GA, Anderson AT, Wright TL, (1968) Mineralogy of sulfides from certain Hawaiian basalts. Econ Geol 63:636–644Google Scholar
  6. Fleet ME, Stone WE (1990) Nickeliferous sulfides in xenoliths, olivine megacrysts, and basaltic glass. Contrib Mineral Petrol 105:629–636Google Scholar
  7. Gunn BM (1971) Trace element partioning during olivine fractionation of Hawaiiari basalts. Chem Geol 8:1–13Google Scholar
  8. Helz RT (1987a) Diverse olivine types in lava of the 1959 eruption of Kilauea volcano and their bearing on eruption dynamics. US Geol Surv Prof Pap 1350:691–722Google Scholar
  9. Helz RT (1987b) Differentiation behavior of Kilauea Iki lava lake, Kilauea volcano, Hawaii: an overview of past and current work. In: Mysen BO (ed) Magmatic processes: physicochemical principles. Geochem Soc Spec Publ 1:241–258Google Scholar
  10. Helz RT, Thornber CR (1987) Geothermometry of Kilauea Iki lava lake. Bull Volcanol 49:651–668Google Scholar
  11. Ho RA, Garcia MO (1988) Origin of differentiated lavas at Kilauea volcano, Hawaii: implications from the 1955 eruption. Bull Volcanol 50:35–46Google Scholar
  12. Holcomb RT (1987) Eruptive history and long-term behaviour of Kilauea Volcano, Hawaii. In: Decker RW, Wright TL, Stauffer P (eds) Volcanism in Hawaii, 2 v. US Geol Surv Prof Pap 1350, 1:261–350Google Scholar
  13. Jaupart C, Tait S (1990) Dynamics of eruptive phenomena. In: Nicholls J, Russell JK (eds) Modern methods of igneous petrology. Rev Mineral 24:213–236Google Scholar
  14. Johnson R, King B-S (1987) Energy-dispersive X-ray fluorescence spectrometry. In: Baedecker P (ed) Methods for geochemical analysis. US Geol Surv Bull 1770:Chapter FGoogle Scholar
  15. Klein FW (1982) Patterns of historical eruptions at Hawaiian volcanoes. J Volcanol Geotherm Res 12:1–35Google Scholar
  16. Kouchi A, Sugawara Y, Kashima K, Sunagawa I (1983) Laboratory growth of sector zoned clinopyroxenes in the system CaMg Si2O6-CaTiAl2O6. Contrib Mineral Petrol 83:177–184Google Scholar
  17. Langmuir CH, Vocke RD Jr, Hanson GN, Hart SR (1978) A general mixing equation with respect to Icelandic basalts. Earth Planet Sci Lett 37:380–392Google Scholar
  18. Leeman WP, Scheidegger KF (1977) Olivine-liquid distribution coefficients and a test for crystal-liquid equilibrium. Earth Planet Sci Lett 35:247–257Google Scholar
  19. Lofgren G (1980) Experimental studies on the dynamic crystallization of silicate melts. In: Hargraves RB (ed) Physics of magmatic processes, pp 487–551Google Scholar
  20. Macdonald GA (1968) Composition and origin of Hawaiian lavas. Geol Soc Am Mem 116:477–522Google Scholar
  21. Macdonald GA, Eaton JP (1964) Hawaiian volcanoes during 1955. US Geol Surv Bull 1171:1–170Google Scholar
  22. MacLean WH, Shimazaki H (1976) The partition of Co, Ni, Cu and Zn between sulfide and silicate liquids. Econ Geol 71:1049–1057Google Scholar
  23. Moore RB, Helz RT, Dzurisin D, Eaton GP, Koyanagi RY, Lipman PW, Lockwood JP, Puniwai GS (1980) The 1977 eruption of Kilauea volcano, Hawaii. J Volcanol Geotherm Res 7:189–210Google Scholar
  24. Nicholls J Stout MZ (1988) Picritic melts in Kilauea-evidence from the 1967–68 Halemaumau and Hiiaka eruptions. J Petrol 29:1031–1057Google Scholar
  25. Nielsen RL (1990) Simulation of igneous differentiation processes. In: Nicholls J, Russell JK (eds) Modern methods of igneous petrology. Rev Mineral 24:65–105Google Scholar
  26. Parfitt EA (1991) The role of rift zone storage in controlling the site and timing of eruptions and intrusions of Kilauea Volcano, Hawaii. J Geophys Res 96:11101–11112Google Scholar
  27. Roeder PL (1974) Activity of iron and olivine solubility in basaltic liquids. Earth Planet Sci Lett 23:397–410Google Scholar
  28. Roeder PL, Emslie RF (1970) Olivine-liquid equilibrium. Contrib Mineral Petrol 29:275–289Google Scholar
  29. Ross M, Huebner JS (1979) Temperature-composition relationships between naturally occurring augite, pigeonite, and orthopyroxene at one bar pressure. Am Mineral 64:1133–1155Google Scholar
  30. Russell JK, Stanley CR (1990) Origins of the 1954–1960 lavas, Kilauea Volcano, Hawaii: major element constraints on shallow reservoir magmatic processes. J Geophys Res 95:5021–5047Google Scholar
  31. Thompson RN, Tilley CE (1969) Melting and crystallization behavior of Kilauea basalts of Hawaii: the lavas of the 1959–60 Kilauea eruption. Earth Planet Sci Lett 5:469–477Google Scholar
  32. Thornber CR, Huebner JS (1985) Dissolution of olivine in basaltic liquids: experimental observations and applications. Am Mineral 70:934–945Google Scholar
  33. Webster AH, Bright NFH (1961) The system iron-titanium-oxygen at 1200°C and oxygen partial pressures between 1 atm and 2×10-14 atm. J Am Ceramic Soc 44:110–116Google Scholar
  34. Wright TL (1971) Chemistry of Kilauea and Mauna Loa lava in time and space. US Geol Surv Prof Pap 735:40 ppGoogle Scholar
  35. Wright TL (1973) Magma mixing as illustrated by the 1959 eruption of Kilauea Volcano, Hawaii. Geol Soc Am Bull 84, 849–858Google Scholar
  36. Wright TL, Fiske RS (1971) Origin of the differentiated and hybrid lavas of Kilauea Volcano, Hawaii. J Petrol 12:1–65Google Scholar
  37. Wright TL, Peck DL (1978) Solidification of Alae lava lake, Hawaii; chapter C. Crystallization and differentiation of the Alae magma. US Geol Surv Prof Pap 935-C:20 ppGoogle Scholar

Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • Rosalind Tuthill Helz
    • 1
  • Thomas L Wright
    • 2
  1. 1.U.S. Geological SurveyRestonUSA
  2. 2.Hawaiian Volcano ObservatoryUSA

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