Bulletin of Volcanology

, Volume 55, Issue 1–2, pp 74–84

Petrology of ultramafic and mafic xenoliths in picrite of Kahoolawe Island, Hawaii

  • E A Rudek
  • R V Fodor
  • G R Bauer


A picrite lava (22 wt% MgO; 35 vol.% ol) along the western shore of the∼1.3–1.4 Ma Kahoolawe tholeiitic shield, Hawaii, contains small xenoliths of harzburgite, lherzolite, norite, and wehrlite. The various rock types have textures where either orthopyroxene, clinopyroxene, or plagioclase is in a poikilitic relationship with olivine. The Mg#s of the olivine, orthopyroxene, and clinopyroxene in this xenolith suite range between 86 and 82; spinel Mg#s range from 60 to 49, and plagioclase is An75–80. A 87Sr/86Sr ratio for one ol-norite xenolith is 0.70444. In comparison, the host picrite has olivine phenocrysts with an average Mg# of 86.2 (range 87.5–84.5), and a whole-rock 87Sr/86Sr ratio of 0.70426. Textural and isotopic information together with mineral compositions indicate that the xenoliths are related to Kahoolawe tholeiitic magmatism, but are not crystallization products of the magma represented by their host picrite. Rather, the xenoliths are crystalline products of earlier primitive liquids (FeO/MgO ranging ∼1 to 1.3) at 5–9 kbar in the cumulate environment of a magma reservoir or conduit system. The presence of ultramafic xenoliths in picrite but not in typical Kahoolawe tholeiitic lava (6–9 wt% MgO) is consistent with replenishment of reservoirs by dense Mg-rich magma emplaced beneath resident, less dense tholeiitic magma. Mg-rich magmas have proximity to reservoir cumulate zones and are therefore more likely than fractionated residual liquids to entrain fragments of cumulate rock.


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  1. Bence AE, Albee AL (1968) Empirical correction factors for the electron microanalysis of silicates and oxides. J Geol 76:382–403Google Scholar
  2. Bohrson WA, Clague DA (1988) Origin of ultramafic xenoliths containing exsolved pyroxenes from Hualalai Volcano, Hawaii. Contrib Mineral Petrol 100:139–155Google Scholar
  3. Clague DA (1987) Hawaiian xenolith populations, magma supply rates, and development of magma chambers. Bull Volcanol 49:577–587Google Scholar
  4. Clague DA (1988) Petrology of ultramafic xenoliths from Loihi seamount, Hawaii. J Petrol 29:1161–1186Google Scholar
  5. Clague DA, Chen C-H (1986) Ocean crust xenoliths from Hualalai, Hawaii. Geol Soc Am, Abstr with Progs 18:No 6, 565Google Scholar
  6. Davis AS, Clague DA (1990) Gabbroic xenoliths from the northern Gorda ridge: implications for magma chambers processes under slow spreading centers. J Geophys Res 95:10885–10905Google Scholar
  7. Dixon JE, Clague DA, Eissen J-P (1986) Gabbroic xenoliths and host ferrobasalt from the southern Juan de Fuca ridge. J Geophys Res 91:3795–3820Google Scholar
  8. Fan Q, Hooper PR (1989) The mineral chemistry of ultramafic xenoliths of eastern China: implications for upper mantle composition and the paleogeotherms. J Petrol 30:1117–1158Google Scholar
  9. Fodor RV, Keil K, Bunch TE (1975) Contributions to the mineral chemistry of Hawaiian rocks IV. Pyroxenes in rocks from Haleakala and West Maui volcanoes, Maui, Hawaii. Contrib Mineral Petrol 50:173–195Google Scholar
  10. Fodor RV, Vandermeyden HJ (1988) Petrology of gabbroic xenoliths from Mauna Kea volcano, Hawaii. J Geophys Res 93:4435–4452Google Scholar
  11. Fodor RV, Keil K, Bunch TE (1977) Contributions to the mineral chemistry of Hawaiian rocks IV. Olivine in rocks from Haleakala and West Maui volcanoes, Maui, Hawaii. Pacific Science 31:299–308Google Scholar
  12. Fodor RV, Bauer GR, Jacobs RS, Bornhorst TJ (1987) Kahoolawe Island, Hawaii: Tholeiitic, alkalic, and unusual hydrothermal(?) ‘enrichment’ characteristics. J Volcanol Geotherm Res 38:171–176Google Scholar
  13. Fodor RV, Frey FA, Bauer GR, Clague DA (1992) Ages, rareearth element enrichment, and petrogenesis of tholeiitic and alkalic basalts from Kahoolawe Island, Hawaii. Contrib Mineral Petrol 110:442–462Google Scholar
  14. Frey FA, Bryan WB, Thompson G (1974) Atlantic Ocean floor: geochemistry and petrology of basalts from Legs 2 and 3 of the Deep-Sea Drilling Project. J Geophys Res 79:5507–5527Google Scholar
  15. Garcia MO, Presti AA (1987) Glass in garnet pyroxenite xenoliths from Kaula Island, Hawaii: product of infiltration of host nephelinite. Geology 15:904–906Google Scholar
  16. Goldberg SA, Butler JR, Fullagar PD (1986) The Bakersville dike swarm: geochronology and petrogenesis of late Proterozoic basaltic magmatism in the southern Appalachian Blue Ridge. Am J Sci 286:403–430Google Scholar
  17. Green DH, Ringwood AE (1967) The genesis of basaltic magmas. Contrib Mineral Petrol 15:103–190Google Scholar
  18. Jackson ED (1968) The character of the lower crust and upper mantle beneath the Hawaiian Islands. 23rd International Geologic Congress, Prague, Proceedings 1:135–150Google Scholar
  19. Jackson ED, Wright TL (1970) Xenoliths in the Honolulu Volcanic Series, Hawaii. J Petrol 11:405–430Google Scholar
  20. Keil K, Fodor RV, Bunch TE (1972) Contributions to the mineral chemistry of Hawaiian rocks II. Feldspars and interstitial material in rocks from Haleakala and West Maui volcanoes, Maui, Hawaii. Contrib Mineral Petrol 37:253–276Google Scholar
  21. Kuno H (1969) Mafic and ultramafic nodules in basaltic rocks of Hawaii. Mem Geol Soc Am 115:189–234Google Scholar
  22. Ludden JN, Thompson G (1979) An evaluation of the behavior of the rare-earth elements during the weathering of sea-floor basalt. Earth Planet Sci Lett 43:85–92Google Scholar
  23. Meyer PS, Dick HJ, Thompson G (1989) Cumulate gabbros from the Southwest Indian Ridge 54°S–7° 16′E: implications for magmatic processes at a slow spreading ridge. Contrib Mineral Petrol 103:44–63Google Scholar
  24. Murase T, McBirney AR (1973) Properties of some common igneous rocks and their melts at high temperatures. Geol Soc Am Bull 84:3563–3592Google Scholar
  25. Nicholls J, Stout MZ (1988) Picrite melts in Kilauea — evidence from the 1967–1968 Halemaumau and Hiiaka eruptions. J Petrol 29:1031–1057Google Scholar
  26. Roden MF, Frey FA, Clague DA (1984) Geochemistry of tholeiitic and alkalic lavas from the Koolau Range, Oahu, Hawaii: implications for Hawaiian volcanism. Earth Planet Sci Lett 69:141–158Google Scholar
  27. Roeder PL, Emslie RF (1970) Olivine-liquid equilibrium. Contrib Mineral Petrol 29:275–291Google Scholar
  28. Rudek EA (1988) Petrology of ultramafic and gabbroic inclusions in basaltic rocks of Kahoolawe Island, Hawaii. North Carolina State U Masters Thesis:52pGoogle Scholar
  29. Rudek EA, Fodor RV, Bauer GR (1988) Petrology of ultramafic and gabbroic inclusions in basaltic of Kahoolawe Island, Hawaii. EOS (abstract) 69:523Google Scholar
  30. Ryan MP, Koyanagi RY, Fiske RS (1981) Modelling the threedimensional structure of macroscopic magma transport systems. Application to Kilauea volcano, Hawaii. J Geophys Res 86:7111–7129Google Scholar
  31. Sen G (1987) Xenoliths associated with the Hawaiian Hot Spot. In: Nixon PH (ed) Mantle xenoliths. John Wiley & Sons Ltd, Chichester, 359–375Google Scholar
  32. Sen G, Jones RE (1990) Cumulate xenolith in Oahu, Hawaii: implications for deep magma chambers and Hawaiian volcanism. Science 249:1154–1157Google Scholar
  33. Sen G, Presnall DC (1986) Petrogenesis of dunite xenoliths from Koolau Volcano, Oahu, Hawaii: implications for Hawaiian volcanism. J Petrol 27:197–217Google Scholar
  34. Sparks RS Huppert HE (1984) Density changes during fractional crystallization of basaltic magmas: fluid dynamical implications. Contrib Mineral Petrol 85:300–309Google Scholar
  35. Stearns HT (1940) Geology and ground-water resources of the islands of Lanai and Kahoolawe, Hawaii. Hawaii Div Hydrography Bull 6Google Scholar
  36. Wells PRA (1977) Pyroxene thermometry in simple and complex systems. Contrib Mineral Petrol 62:129–139Google Scholar
  37. West HB, Gerlach DC, Leeman WP, Garcia MO (1987) Isotopic constraints on the origin of Hawaiian lavas from Maui Volcanic Complex, Hawaii. Nature 330:216–220Google Scholar
  38. White RW (1966) Ultramafic inclusions in basaltic rocks from Hawaii. Contrib Mineral Petrol 12:245–314Google Scholar
  39. Wilkinson JFG, Hensel HD (1988) The petrology of some picrites from Mauna Loa and Kilauea volcanoes, Hawaii. Contrib Mineral Petrol 98:326–345Google Scholar

Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • E A Rudek
    • 1
  • R V Fodor
    • 1
  • G R Bauer
    • 2
  1. 1.Department of Marine, Earth, and Atmospheric SciencesNorth Carolina State UniversityRaleighUSA
  2. 2.Department of Land and Natural ResourcesHonoluluUSA
  3. 3.Sirrine Environmental ConsultantsFremont

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