Variations in the Lava of the 1959 Eruption in Kilauea Iki 1 
Gordon A. Macdonald and Takashi Katsura 2 
In RECENT years the Hawaiian Islands have 
become of great importance in studies concerned 
with igneous petrogenic theory. This is partly 
because of the total absence in that region of 
sialic crust that might affect the formation of 
other rock types by its assimilation in rising 
magma. Partly, also, it is because of the exten- 
sive lateral and vertical exposure of successions 
of rocks, the structural and stratigraphic rela- 
tionships of which are now well known. These 
conditions have attracted to the area workers 
from many parts of the world, and progress in 
knowledge of Hawaiian rocks has been rapid. 
The knowledge is, of course, the accumulation 
of the findings of many workers, starting with 
the visit of J. D. Dana to the islands in 1840, 
as a member of the U. S. Exploring Expedition. 
Outstanding among recent workers are Hisashi 
Kuno of Tokyo University, P. Niggli of the 
University of Zurich, C. E.' Tilley of Cambridge 
University, H. S. Yoder of the Geophysical Lab- 
oratory of the Carnegie Institution of Washing- 
ton, and H. A. Powers of the United States 
Geological Survey. 
During I960 and 1961 two studies have 
largely confirmed, but also extended and some- 
what modified, the previous petrogenic picture. 
In April, I960, the junior author of this paper, 
on leave from the Tokyo Institute of Technol- 
ogy, commenced a series of chemical analyses 
of Hawaiian lavas at the University of Hawaii 
under a National Science Foundation grant to 
the senior author. At the end of March, 1961, 
approximately 150 new analyses, primarily of 
the hitherto largely neglected "primitive” lavas 
of the Hawaiian volcanoes, had been completed. 
These have helped fill important gaps in the 
basic knowledge of Hawaiian rocks. Study of 
them is continuing. 
During July, I960, a core hole was drilled in 
the crust of the recently erupted lava pool in 
Kilauea Iki crater of Kilauea volcano, and pene- 
1 Hawaii Institute of Geophysics, Contribution 23. 
Manuscript received March 21, 1961. 
2 University of Hawaii. 
trated into the molten lava beneath. The results 
of study of the drill-hole samples and samples 
of the earlier lava of the eruption are reported 
in this paper. 
Acknowledgments. The core hole in the crust 
of the Kilauea Iki lava pool was drilled for the 
Lawrence Radiation Laboratory of the Univer- 
sity of California in cooperation with the Uni- 
versity of Hawaii, and the chemical analyses of 
the core samples were done at the University 
of Hawaii for the Lawrence Radiation Labora- 
tory. The entire program is a part of the Law- 
rence Radiation Laboratory’s Plowshare Program 
for the development of peaceful uses of atomic 
energy. The results of other aspects of the in- 
vestigation will be published by members of 
the staff of the Lawrence Radiation Laboratory. 
The drilling was done by a crew in the em- 
ploy of Nat Whiton of Honolulu, under the 
general supervision of Walter Bennett and 
Donald E. Rawson of the Lawrence Laboratory. 
General scientific supervision was furnished by 
Macdonald. Thanks are due to the National 
Park Service for permitting the drilling for 
scientific purposes within Hawaii National Park, 
and to the Lawrence Radiation Laboratory for 
permitting us to publish the chemical analyses 
and other data on the core samples. 
The sample of Pele’s hair analyzed was col- 
lected and given to us by Mr. H. Ikawa, of 
the Department of Agronomy, University of 
Hawaii. 
Two analyses (S-l and S-2) in Table 1 are 
by J. H. Scoon of Cambridge University. 
We wish to express our thanks to A. T. Ab- 
bott, of the University of Hawaii, for critical 
reading of the manuscript. 
HAWAIIAN ROCK SUITES 
In the classical Mull Memoir (1924), E. B. 
Bailey and his associates distinguished three 
principal rock types, which they termed the plat- 
eau, central porphyritic, and central nonporphy- 
ritic types. In 1933, W. Q. Kennedy applied the 
names olivine basalt and tholeiite to the first and 
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