Petrology, Mineralogy, 

and Geochemistry of the 

East Molokai Volcanic Series, Hawaii 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 961 

Petrology, Mineralogy, and 

Geochemistry of the East Molokai 

Volcanic Series, Hawaii 

By MELVIN H. BEESON 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 961 

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1976 
UNITED STATES DEPARTMENT OF THE INTERIOR 

THOMAS S. KLEPPE, Secretary 

GEOLOGICAL SURVEY 

V. E. McKelvey, Director 

Library of Congress catalog-card No. 76-12795 

For ~ale by the Superintendent of Documents, U.S. Government Printing Office 

Washington, D.C. 20402 

Stock Number 024-001-02810-7 
CONTENTS 

Page 

1\bstract__________________________________________________ 1 

Page 

Phenocryst-free compositions ------------------------------ 14 

Introduction ---------------------------------------------- 1 Mineralogy ____ _ _ __ __ _ _ ______ _ _ ________ __ __________ _ _____ 21 

Previous investigations------------------------------------ 3 Compositional variation of olivine______________________ 21 

Purpose and scope ---------------------------------------- 4 Compositional variation of clinopyroxene ______________ 25 

1\nalytical procedures ------------------------------------ 4 Compositional variation of plagioclase__________________ 27 

Stratigraphy and petrology-------------------------------- 6 Compositional variation of opaque minerals ____________ 28 

Whole-rock compositions ---------------------------------- 11 Summary ------------------------------------------------ 30 

References________________________________________________ 33 

FIGURE 1. 

2. 

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15. 

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22. 

23. 

24. 

25. 

26. 

ILLUSTRATIONS 

Page 

Index map of Hawaiian Archipelago ------------------------------------------------------------------------------- 1 

Geologic map of island of Molokai showing location of Kalaupapa section----------------------------_________________ 2 

Oblique aerial photograph of trail along which Kalaupapa section was sampled ______________________ ----------------- 5 

Photograph of thin-bedded flows of tholeiitic basalt exposed along north coast of Molokai just west of mouth of Waikolu 

\Talley------------------------------------------------------------------------------------------------------- 7 

Histogram showing phenocryst content of lavas of Kalaupapa section . ----------------------------------------------- 8 

Photomicrographs of a resorbed olivine phenocryst from Kalaupapa section showing intratelluric alteration and fresh 

overgrowth ___________________________________________________________________________________________________ 9 

Photomicrograph of olivine phenocryst from Kalaupapa section showing growth resorption, alteration, regrowth, 

resorption, and further alteration ----------------------------------------------------------------------------- 10 

Photomicrographs of plagioclase phenocryst from Kalaupapa section showing tabular opaque (magnetite) inclusions 

oriented parallel to (010) twin planes ------------------------------------------------------------------------- 10 

Total alkali-silica diagram of dry-reduced whole-rock compositions from Kalaupapa section __________ ----------------- 12 

Olivine, nepheline, silica diagram of dry-reduced whole-rock compositions from Kalaupapa section ____ ----------------- 12 

1\FM diagram of dry-reduced whole-rock compositions from Kalaupapa section ______________________ ----------------- 13 

Magnesia variation diagram of dry-reduced whole-rock compositions from Kalaupapa section ________ ----------------- 14 

Graph showing weight percent of oxides in dry-reduced whole-rock compositions from Kalaupapa section plotted against 

relative stratigraphic position __ _ _ __ __ _____ _ _ ___ _ _ _ _ _______ _ _ _____ _ _ _ _ _____ _ ______ _ _ ____ __ _ _ __ _ _ _______ _ ____ _ _ _ 16 

Total alkali-silica diagram of phenocryst-free compositions from Kalaupapa section __________________ ----------------- 17 

AFM diagram of phenocryst-free compositions from Kalaupapa section ------------------------------ _________________ 17 

Magnesia variation diagram of phenocryst-free compositions from Kalaupapa section. ________________ ----------------- 18 

Graph showing weight percent of oxides in phenocryst-free compositions from Kalaupapa section plotted against relative 

stratigraphic position----------------------------------------------------------------------------------------- 21 

Total iron-variation of diagram of olivine from Kalaupapa section --------------------------------------------------- 22 

Graph showing weight percent of oxides in olivines from Kalaupapa section plotted against relative stratigraphic 

position ----------------------------------------------------------------------------------------------------- 23 

Diagram showing composition of clinopyroxenes in Kalaupapa section on pyroxene quadrilateraL _____ ----------------- 25 

Diagram showing compositional variation of clinopyroxenes in subsections of Kalaupapa section plotted on a part of 

pyroxene quadrilateral --------------------------------------------------------------------------------------- 25 

Graph showing weight percent of oxides of elinopyroxene from Kalaupapa section ____________________ ----------------- 26 

Albite, orthoclase, anorthite diagram of plagioclase from Kalaupapa section ________________________ ----------------- 28 

Graph showing weight percent of oxides in plagioclase from Kalaupapa section plotted against relative stratigraphic 

position ----------------------------------------------------------------------------------------------------- 29 

Graph showing variation of Al2 0 3 , Ti02 , MgO, and 'FeO' plotted against Cr2 0 3 in opaque minerals from Kalaupapa section _______________________________________________________________________________________________________ 31 

Diagrams showing compositional variation of opaque minerals from Kalaupapa section with respect to FeAl2 0 4 -Fe2 Ti04 

FeCr2 0 4 - MgAl2 0 4 - Mg2Ti04 - MgCr2 0 4 trigonal prism ------------------------------------------------------- 32 

III 
IV 

TABLE 1. 

2. 

3. 

4. 

5. 

6. 

7. 

CONTENTS 

TABLES 

Page 

Chemical analyses of rocks from the Kalaupapa section ------------------------------------------------------------ 36 

Chemical analyses of rocks on a phenocryst-free basis from the Kalaupapa section ---------------------------------- 38 

Chemical analyses of olivines from the Kalaupapa section---------------------------------------------------------- 40 

Chemical analyses of olivine alteration rims from the Kalaupapa section-------------------------------------------- 42 

Chemical analyses of clinopyroxenes from the Kalaupapa section -------------------------------------------------- 45 

Chemical analyses of plagioclases from the Kalaupapa section------------------------------------------------------ 48 

Chemical analyses of opaque minerals from the Kalaupapa section ________________________________ ------------------ 51 
PETROLOGY, MINERALOGY, AND GEOCHEMISTRY OF THE 

EAST MOLOKAI VOLCANIC SERIES, HAW All 

By ~1ELVIN H. BEESON 

ABSTRACT 

The Kalaupapa section, a 305-m (1,000-ftJ-thick section of mostly 

porphyritic lavas that range from transitional tholeiitic to alkalic to 

distinctly alkalic, is exposed along the trail that leads up the cliff 

southwest of Kalaupapa on East Molokai Volcano, Hawaii. On the 

basis of whole-rock composition, the section was divided into eight 

subsections characterized by enrichment upward in the section in 

Na20, K20, and Al203 and depletion in MgO, NiO, and Cr20 3. Enrichment in Na20, K20, and P20 5 and depletion in NiO and Cr20 3 are 

also evident upward in the section as a whole. Olivine and 

clinopyroxene phenocryst content of the lavas decreases and plagioclase phenocryst content increases (with minor variations) upward in 

the subsections. 

Analyses of phenocrysts and some groundmass minerals also show 

variation up the section. Clinopyroxene increases upward in Na20 

and Ti02 content and decreases in MgO; olivine increases upward in 

FeO, CaO, and MnO content and decreases in MgO; and plagioclase 

increases upward in Na20 and K20 content and decreases in Al20 3 

and CaO. Plagioclase also shows an upward increase in K20 in the 

subsections. 

Phenocryst-free compositions were determined by subtracting 

phenocrysts from the whole-rock compositions on the basis of their 

modal amounts and compositions. The subsections defined on the 

basis of whole-rock compositions also remain intact when defined on 

the basis of phenocryst-free compositions; therefore, not all the chemical variation in the subsections can be attributed to variation in 

phenocryst content. 

The subsections are believed to represent distinct magmatic 

batches similar to the ones that were proposed to explain the chemical 

variation of tholeiites and the eruptive histories of Hawaiian volcanoes and that were recently confirmed from a detailed study of the 

lavas ofKilauea. Concentrations of phenocrysts in some lavas mask 

trends in composition. Calculation of phenocryst-free eompositions 

has, to a first approximation, removed variation of the whole-rock 

compositions resulting from shallow fractional crystallization and has 

revealed earlier (and deeper) fractionation dominantly eontrolled by 

aluminous clinopyroxene. The more fractionated character of the 

subsections in the upper part of the section, starting with olivine 

basalt and ending with mugearite, perhaps reflects changing conditions in the zone of magma generation prior to phenocryst growth. 

INTRODUCTION 

The island of Molokai, a volcanic doublet, is the fifth 

in size of the islands of the Hawaiian Archipelago, 

which extends about 2,500 km (1,554 mi) southeastward across the central Pacific Ocean from K ure on the 

northwest to Hawaii on the southeast (fig. 1). The 

broadly linear chain of islands that make up the archipelago caps the Hawaiian Ridge. The ridge is bordered by the Hawaiian Moat (or Deep) which is in turn 

bordered by the Hawaiian Arch (or Rise). These three 

topographic features, the ridge, moat, and arch, are 

superposed on a broad elongate topographic high, the 

Hawaiian Swell (Betz and Hess, 1942; Dietz and 

Menard, 1953). Dana (1849, 1890) recognized from 

geomorphic evidence that extinction of the chain progressed from northwest to southeast, and McDougall 

(1964) confirmed the general progression with 

potassium-argon ages of lavas from Kauai, Oahu, 

Molokai, Maui, and Hawaii. The general progression of 

ages of the Hawaiian-Emperor chain and its relation to 

Cenozoic circum pacific tectonics have been described by 

Jackson, Silver, and Dalrymple (1972) and Dalrymple, 

Silver, and Jackson (1973). Fiske and Jackson (1972) 

investigated the influef· ce of regional structure and 

local gravitational str sses on the orientation and 

growth of Hawaiian vol 1 anic rifts. Macdonald and Abbott (1970) gave an excellent summary of the geomorphology of the Hawaiian Islands and of the processes that formed and are continuing to form them. Their 

summary contains a geologic sketch of each ofthe major 

180° 170° 160° 1 50° 30~ r-r--------,----------.-------------, 

,Kure 

·=--Midway 

0 

0 

1000 MILES 

1000 KILOMETRES 

Nihoa 1 Kauai 

..qFi'c • J. Molokai 

1-ftp~l....q Oahu!' ~~Maui 

Go ~ 

~Hawaii 

PACIFIC OCEAN 

FIGURE 1.-lndex map of the Hawaiian Archipelago (after Jackson, 

1968, Fig. 1 ). 

1 
2 EAST MOLOKAI VOLCANIC SERIES 

windward islands (extending from Kauai to Hawaii) 

and the leeward islands (extending from Kure to Nihoa) 

as a group. 

Molokai is an elongate island 78 x 16 km ( 48.5 x 10 

mi), with its long dimensions oriented east-west (fig. 2). 

It is made up of two coalescing volcanoes, West Molokai 1 

Volcano, which rises 421 m (1,380 ft) above sea, level, 

and East Molokai Volcano, which rises 1,515 m (4,970 

ft) above sea level. Both East and West Molokai Volcanoes are elongate in plan reflecting the structural 

control of several major rift zones. West Molokai has 

three rift zones oriented due east, northwest, and westsouthwest. East Molokai probably was controlled by 

stress patterns set up in the edifice of the older West 

Molokai Volcano whose sloping apron it pierced (Fiske 

and Jackson, 1972). West Molokai is believed by Fiske 

and Jackson (1972) to have grown as an nisolated" 

edifice that was influenced by the regional structure of 

1 West Molokai Volcano is also referred to as Mauna Loa, but this name is not used here to 

avoid confusion with the better known Mauna Loa of the island of Hawaii. 

Laau 

Point 

0 

I 

0 

2 4 MILES 

I 1 I 

2 4 KILOMETRES 

the Pacific basin. However, if the prolongation of the 

west-southwest rift of West Molokai Volcano (Penguin 

Bank) is an older independent shield built along the 

same trend as the main rift zone of West Molokai Volcano (Macdonald and Abbott, 1970), then the orientation of the rift system of West Molokai reflects gravitational stress patterns set up in this older independent 

shield. 

The north coast of Molokai, especially its eastern 

part, is bounded by a spectacular pali (cliff) that is 

locally more than 915 m (3,000 ft) high. Several deep 

amphitheater-shaped valleys, notably Wailau, Pelekunu, and Waikolu, have been cut into the pali. Two of 

these, Wailau and Pelekunu, dominate the drainage 

system of the northern coast, probably because they 

head in the highly altered, and therefore easily eroded, 

rocks of the caldera complex. The drainage system on 

the south (leeward) flank of East Molokai is not so deeply incised as the drainage system of the northern 

coast, because it receives far less rainfall. Flat-topped 

interfluves along the south flank permit reasonably re-

> > ~ ~ > iO iO ~ 

> > iO 

> 

55' Kamalo 50' 

EXPLANATION 

SEDIMENTARY ROCKS 

Note: Dikes not shown 

0 

s:: ~ 0 

s:: Iii! ~ Lithified dunes 8 

'Q) 

Younger and 2i:; 

older alluvium ~ 

0 

.... 

.~ 

£ 

Marine limestone 

Contact 

_____.1___ --

Fault 

Bar and ball on down thrown side 

VOLCANIC ROCKS 

llllllllllllllllt'ent 

Kalaupapa Basalt 

0 

Mokuhooniki tuff cone 

East Molokai Volcanic Series 

>< ~Vent ~ 

< z Upper andesite member ~ 

~ 

E-t 

< ;:J 

mJIIVent ~ 

Cl Lower basalt Caldera complex 

member 

EROSIONAL UNCONFORMITY 

West Molokai Volcanic Series 

~Vent 

Basalt 

FIGURE 2.-Geologic map of island of Molokai showing location of Kalaupapa section (after Stearns, 1946, fig. 18; 

Stearns and Macdonald, 1947). 
PREVIOUS INVESTIGATIONS 3 

liable reconstruction of the preerosional edifice, which 

shows that, disregarding subsidence, East Molokai was 

never much higher than its present 1,515-rn (4,970-ft) 

elevation. However, considering possible subsidence of 

2,300 m±500 m (7,550±1,640 ft), calculated from data 

of Moore (1970), it may have reached an elevation of 

3,815±500 m (12,500± 1,640 ft), nearly as high as 

Mauna Loa and Mauna Kea on the island of Hawaii. 

West Molokai, the smaller and older of the two 

Molokai volcanoes, is made up of thin-bedded flows of 

tholeiitic basalt with many thin ( <Vs m) interlayers of 

vitric tuff. It never formed a caldera or had significant 

eruptions of alkalic basalt (Macdonald and Abbott, 

1970). 

East Molokai, on the other hand, has a well-developed 

caldera stage and erupted about 490 m (1,610 ft) of 

transitional and alkalic lavas in the Kalaupapa area 

some 70 m (230ft) of which are mugearite and hawaiite 

(the upper member of Stearns and Macdonald (1947)). 

McDougall (1964) dated the mugearites of the upper 

member at 1.31-1.41 m.y. (million years) and several 

flows in the upper part of the alkalic basalt flows (the 

lower member of Stearns and Macdonald (1947)) at 

1.48-1.49 m.y. The tholeiitic lavas ofEast Molokai have 

not yet been dated, and so the absolute chronology of the 

major parts of the two edifices remains in doubt. 

PREVIOUS INVESTIGATIONS 

The earliest work on the petrology of Molokai was 

done by M·ohle (1902), who studied 50 san1ples from 

various localities scattered over the island but concentrated mostly along the northern pali (cliff) in the vicinity of Kalaupapa. M·ohle (1902) considered the lavas of 

Molokai to be of typical basaltic character consisting of 

plagioclase, augite, olivine, and magnetite. He distinguished three groups connected by intermediate rocks: 

(1) olivine-bearing basalts in which olivine content is 

not high, (2) rocks in which olivine is rare or entirely 

lacking, and (3) rocks in which olivine is abundant and 

augite rare or lacking. He also reported a nephelinebearing rock from Kalae. Stearns and Macdonald (194 7) 

reported rocks corresponding to the first and second 

groups but found none that correspond to M·athle's third 

group on Molokai or any of the other Hawaiian islands. 

Because they did not find any nepheline-bearing rocks 

on Molokai, they concluded that some of the rocks 

studied by Mahle (1902) were mislabeled and actually 

came from Oahu. Lindgren (1903) made the first field 

study of Molokai to evaluate the water resources but 

paid little attention to petrology, except to note that the 

rocks were normal somewhat glassy feldspar basalts 

containing olivine and a few plagioclase phenocrysts. 

While exploring the headwaters of Wailau Stream, he 

did note a coarse-grained intrusive rock that he termed 

a very coarse grained olivine diabase. 

Powers (1920) visited all the windward islands and 

judged Wailau (East Molokai) Volcano to consist largely 

of feldspar basalt with rare alkali trachyte. He was the 

first to recognize that the Kalaupapa peninsula, north of 

the pali, is a young olivine basalt cone and not part of a 

sunken area as Lindgren (1903) believed. 

The most comprehensive petrographic study of 

Molokai was made by Stearns and Macdonald (1947). 

Although their report was primarily concerned with 

ground water resources of Molokai, it gives the most 

detailed account of the geology and the only geologic 

map of Molokai to date. The lavas of West Molokai 

Volcano are described as basalts, olivine basalts, and 

picrites of primitive type. Because the flows are very 

thin, less than 1 m thick, and are poorer in olivine 

phenocrysts than is common in Hawaiian tholeiites, 

they are considered by Stearns and Macdonald (1947) to 

have been erupted in a very fluid condition. Only a thin 

discontinuous cap of alkalic olivine basalt and hawaiite 

is reported on West Molokai (Macdonald and Abbott, 

1970). 

Stearns and Macdonald (1947) reported the petrology 

of the stratigraphic section measured along the trail 

that leads down the great northern pali southwest of 

Kalaupapa-the subject of this study. This stratigraphic section, considered by them to be characteristic 

of the East Molokai Volcanic Series, is designated its 

type section and is herein referred to as the Kalaupapa 

section (fig. 2). 

Stearns and Macdonald (1947) reported that augite 

phenocrysts are about as abundant as olivine phenocrysts and that these phenocrysts constitute 40-60 

percent of the rock. However, no flows observed in the 

Kalaupapa section that contain more than 5 percent 

olivine phenocrysts have nearly equal abundances of 

augite and olivine phenocrysts. Augite phenocrysts are 

generally only about a third as abundant as olivine, and 

in only one sample does the augite phenocryst content 

amount to about 60 percent of the olivine phenocryst 

content. Phenocrysts constitute more than 20 percent of 

many rocks, but none in which modes were made exceed 

30 percent of the rock, and none that I observed approach the 40-60 percent reported by Stearns and Macdonald (1947). 

The general life history of Hawaiian volcanoes has 

been divided into four stages (Macdonald and Abbott, 

1970; modified from Stearns, 1946): 

1. Youthful stage, characterized by a shield, consisting 

almost entirely of thin basalt flows, that has been 

built by frequent eruption of very fluid tholeiitic 

lavas. The lavas of this stage range from basalt 

almost free of olivine phenocrysts to oceanites con-
4 EAST MOLOKAI VOLCANIC SERIES 

taining more than 50 percent olivine phenocrysts 

(Macdonald and Katsura, 1962; Macdonald and 

Abbott, 1970). 

2. Mature stage, characterized by a caldera complex 

that formed by repeated collapse of the summit 

area and infilling of the resulting caldera by lava. 

Activity during the mature stage was still vigorous, and many of the tholeiitic lava flows produced 

were thicker than in the youthful stage because 

they were ponded in the caldera. 

3. Old stage, characterized by a cap of alkalic basalt 

that was built over the top and upper flanks of the 

shield and that thins away from the summit. Eruptions at this stage were less frequent and more 

explosive and produced thicker flows and steeper 

slopes than the earlier tholeiitic eruptions. The 

lava flows of this stage are commonly separated by 

weathered zones and a few soil zones or local erosional unconformities. 

4. Rejuvenated stage, following a long period of volcanic quiescence. The flows of this stage are separated from those of the previous stage by a 

profound erosional unconformity. Many occur as 

intracanyon flows. Most lavas of this stage are 

critically undE~rsaturated and contain nepheline 

or nepheline and melilite (Winchell, 1947; Jackson and Wright, 1970; Macdonald and Abbott, 

1970). 

This history is an idealized scheme, for not all volcanoes show the entire sequence and the sequence may 

be terminated at any stage. West Molokai Volcano, for 

example, ceased eruption before reaching the mature 

stage and has no caldera and few alkalic flows. East 

Molokai Volcano, on the other hand, has as complete a 

sequence as any of the volcanoes in the Hawaiian chain. 

It is probably just entering the rejuvenated stage. Posterosional eruptions have formed the Kalaupapa Peninsula and Mokuhooniki Island, but unlike most of the 

posterosionallavas ofKauai (the Koloa Volcanic Series) 

and Oahu (the Honolulu Volcanic Series), these contain 

no nepheline. 

PURPOSE AND SCOPE 

This study was undertaken to determine what, if any, 

systematic changes in chemistry and petrology of the 

lavas could be detected through the stratigraphic section and how removal of phenocrysts from the wholerock compositions affects the fractionation trends. All 

too frequently, chemical analyses from an area are plotted with little or no stratigraphic control, making it 

impossible to relate the presumed fractionation trends 

to stratigraphy. Because analysis of all phenocryst minerals was required to determine the phenocryst-free 

compositions, an evaluation of the variation of mineral 

compositions in different parts of the section was also 

possible. 

Most of the original plan to sample lavas of the 

tholeiitic suite and work upward into the alkalic suite 

has been accomplished. The flows in the lower part of 

the section are petrologically alkalic but are compositionally tholeiitic. They are probably best classified as 

transitional between tholeiitic and alkalic. The flows in 

the upper part of the section are unquestionably alkalic. 

Several stratigraphic sections were sampled, but detailed work has been done only on the Kalaupapa section (fig. 3). A reasonably complete sampling of the 

upper 305m (1,000 ft) of the section was made, but only 

sparce sampling was done in the lower 180m (600ft), 

which is largely covered by talus. 

Flows presumed to be tholeiitic have been sampled in 

Pelekunu and Waikolu Valleys, but limited time and 

difficult topography prevented sampling of a complete 

section. None of the rocks of the caldera complex that 

are exposed in Pelekunu and Wailau Valleys have been 

included in this study, but they merit a study in themselves inasmuch as the structure of this exhumed caldera complex appears to be similar to the one developing 

on Kilauea. 

Acknowledgments.-Grateful appreciation is expressed to those in U.S. Geological Survey who provided 

technical assistance during this study. V. C. Smith and 

R. L. Rahill performed chemical analyses, and Keith 

Bargar separated and X-rayed olivine alteration products. Helpful discussions and critical reviews of E. D. 

Jackson, R. G. Coleman, K. J. Murata, and T. L. Wright 

of the U.S. Geological Survey, and of A. C. Waters, R. S. 

Coe, and 0. T. Tobisch of the University of California, 

Santa Cruz, are sincerely appreciated. Field assistance 

by my wife, Naomi K. Beeson, is gratefully acknowledged. 

ANALYTICAL PROCEDURES 

After preliminary petrographic examination of all 

the samples taken from the Kalaupapa section, 26 samples from 24 flows were selected for further study. 

Whole-rock compositions were determined in the 

analytical laboratories ofthe U.S. Geological Survey in 

Denver, Colo., and phenocryst and groundmass minerals were analyzed by the author. In order to assure that 

the phenocryst modes would be representative of the 

sample analyzed for whole-rock chemistry, two slabs 

were taken from opposite sides of the samples submitted 

for whole-rock analysis. These two slabs were fine 

ground with 600-mesh abrasive, sprayed with plastic, 

and inscribed with a 1-cm2 grid. Using a lOx 10 mm 

reticle, 121 points were counted in each of the 1-cm 

squares. A drop of distilled water between the rock slab 

and the reticle significantly improved the visibility of 
ANALYTICAL PROCEDURES 

FIGURE 3.-0blique aerial photograph ofpali near Kalaupapa peninsula showing trail along which Kalaupapa section 

was sampled. A-Z, sample localities from base of section upward. Pali is about 490 m (1,610 ft) high. View to south. 

Photograph by U.S. Navy. 

5 
6 EAST MOLOKAI VOLCANIC SERIES 

the phenocrysts. Following the procedure of Jackson 

and Ross (1956), a minimum ofl,OOO points was counted 

for each sample, and with few exceptions, an area at 

least 100 times that of the largest phenocryst was covered. The volume percent mode was converted to 

weight percent using an estimated average density of 

3.5 for olivine, 3.35 for clinopyroxene, 2. 7 for plagioclase, and 2.9 for the groundmass. The mineral densities 

were calculated from end-member densities and average phenocryst compositions, and the groundmass density was estimated from densities of crystalline rocks 

(Daly and others, 1966). 

X-ray diffractograms of olivine alteration rims were 

made with CuKa radiation using a Phillips X-ray 

generator and diffraction unit equipped with a graphite 

crystal monochrometer. Mineral analyses were made 

with an ARL EMX-SM electron microprobe using 

natural mineral standards. All data were corrected for 

drift, background, matrix absorption, characteristic 

fluorescence, and atomic number effects (Beeson, 1967; 

Beaman and Isasi, 1970). During analysis of phenocrysts, the beam was scanned rapidly over a 10 x 10 J.Lm 

raster, which helps to even out inhomogeneities and 

gives a better average composition. The mineral 

analyses are believed accurate to ±2 percent of the 

amount present for major elements and± 10 percent of 

the amount present for minor elements. 

The phenocryst compositions were subtracted from 

the whole-rock composition in proportion to their modal 

abundance. Because some of the olivine phenocrysts are 

altered, it was deemed advisable to make modes for the 

amounts of fresh and altered olivine and subtract appropriate amounts of fresh and altered olivine. This 

procedure appears to have been justified because two 

samples, I and M, with relatively abundant and the 

most severely altered olivine phenocrysts, do not depart 

appreciably from the trend established by the samples 

with relatively few olivine phenocrysts and those in 

which olivine phenocrysts are only slightly altered. 

It is recognized that subtraction of phenocryst compositions derived by microprobe analysis yields only a 

first approximation to phenocryst-free lava compositions because of the inhomogeneity of the phenocrysts 

as a whole. Neither chromite inclusions in olivine, 

magnetite inclusions in plagioclase, nor other inclusions in the phenocrysts have been taken into account. 

STRATIGRAPHY AND PETROLOGY 

Three stratigraphic sections of the East Molokai Volcanic Series were sampled on a flow-by-flow basis: one 

along the trail to Kalaupapa, one along the road leading 

into Halawa Valley from the south, and one up Lama 

Loa Head north ofHalawa Valley. The Kalaupapa section was selected for detailed study because it is thickest 

and exposes rocks lower in the volcanic pile than the 

other two. The two sections in Halawa Valley contain 

fewer olivine phenocrysts relative to plagioclase and are 

much like the upper part of Kalaupapa section in that 

respect. 

No attempt was made to trace the flows laterally 

because of the steep slope, but samples were taken up 

the trail on the assumption that vertical position can be 

directly correlated with stratigraphic position. Such an 

assumption is reasonable because no evidence of erosional unconformities was seen and in general, even in a 

late mature stage, the frequency of eruption of Hawaiian volcanoes is high enough to prevent development of 

extensive stream channels. Flows are commonly separated by weathered aa clinkers and in a few places by 

baked red soil zones, usually less than about% m (1 ft) 

thick. Compared with the West Molokai Volcanic 

Series, there seem to be fewer vitric ash beds separating 

lava flows, which is curious in light of the fact that the 

flows in the Kalaupapa section are mostly alkalic, and 

they tend to be erupted more explosively than tholeiitic 

ones. 

Because sills are present in some Hawaii sections, 

coarsely crystalline dense rocks without clinkers were 

looked for, but none were found. Presumably none of the 

flows sampled are really sills. 

The Kalaupapa section lies about 12 km (6.8 mi) 

west-northwest of the caldera complex, as shown by 

Stearns and Macdonald (1947) (fig. 2). On the basis of 

gravity contours (Moore and Krivoy, 1965) and extrapolation of dikes that crop out on the pali due south of 

Kalaupapa, the section lies about 1 km (.62 mi) south of 

the west-northwest rift zone. 

Wright and Fiske (1971) presented a model for the 

conduit system of the east rift of Kilauea, in which 

magma from the summit area migrates outward along 

separate subparallel conduits. The magma is stored in 

pockets along the rift zone where it may be fractionated 

to various degrees and later flushed by batches of unfractionated lava migrating outward from the summit. 

Lavas in the Kalaupapa section may have originated in 

this general setting. As a result, the compositional variations may not be typical of summit lavas but rather of 

lavas from rift-zone eruptions. Nonetheless, any longterm variation in the lavas, not related to fractional 

crystallization in the shallow rift-zone chambers, 

should provide information on deeper (more fundamental?) changes in magma composition. It cannot be definitely established that all or part of the lavas in the 

Kalaupapa section were derived from rift-zone eruptions, but by analogy with Kilauea, most of the flows 

near the rift zone are probably not summit eruptions. 

The gentle (2°) slope of the flows away from the rift zone 

in the Kalaupapa section argues for this rift-zone origin. 
STRATIGRAPHY AND PETROLOGY 7 

It is unlikely that the Kalaupapa section records the 

entire history of the East Molokai Volcanic Series. The 

period represented by accumulation of this section 

probably also includes many hiatuses resulting from a 

statistical distribution of the lavas from a volcano 

erupting frequently enough to maintain a nearly symmetrical form. 

Stearns and Macdonald (1947) divided the East 

Molokai Volcanic Series into two members: (1) a lower 

member composed of basalts, olivine basalts, and 

picrite-basalts of the primitive and ankaramite types 

(2) and an upper member composed of andesine andesites (hawaiites), oligoclase andesites (mugearites), and 

trachytes. Picrites of the primitive type are reported to 

be present in the lower part of the lower member, and 

picrites of the ankaramite type are reported to be present in the upper part of the lower member. All the 

"little differentiated" lavas of the lower member are not 

tholeiitic as McDougall (1964) presumed, though the 

lavas of the lower part of the lower member, which 

Stearns and Macdonald (194 7) described as containing 

picrites of the primitive type, probably are tholeiitic. 

The lavas of the upper part of the lower member, which 

McDougall dated and which Stearns and Macdonald 

(194 7) described as containing picrites of ankaramite 

type, are distinctly alkalic. 

No picrites of the primitive type were observed in the 

upper two-thirds of the Kalaupapa section, which was 

sampled in detail, or in the lower third, which was only 

sparsely sampled because it was covered by talus. Samples from the base of the pali about 1 km (0.62 mi) east of 

the Kalaupapa section were found to contain augite as 

phenocrysts and in the groundmass but no pigeonite or 

hypersthene. Petrologically they, and presumably the 

rest of the flows in the section, are alkalic. 

Rocks that a re apparently tholeiitic crop out at the 

east side of the mouth ofWaikolu Valley. The flows are 

very thin bedded, 1f3-PI3 m (1-4 ft) thick, with thin 

unweathered clinkers separating them, and they contain almost no olivine either as phenocrysts or in the 

groundmass. In these respects they resemble the 

tholeiitic rocks of West Molokai but differ in that they 

contain no vitric tuff beds between flows. This section of 

tholeiites(?) (fig. 4) is unusual and may be unique in the 

Hawaiian Islands. Other basalts, more typical of the 

Hawaiian tholeiites, are exposed outside the caldera 

complex in Pelekunu and Wailau Valleys. 

Approximately 80 flows are present in the Kalaupapa 

section. The flows of the lower member range in thickness from about 1 to 20 m (3-70 ft) and average about 

6 m (20ft). Those of the upper member range in thickness from about 6 to 24 m (20-80 ft) and average about 

9 m (30ft). 

McDougall (1964) obtained potassium-argon ages for 

FIGURE 4.-Thin-bedded flows of tholeiitic basalt exposed 

along north coast of Molokai just west of mouth of 

Waikolu Valley. Average thickness of flows is about 

0.7 m (2ft.) 

three flows in this section. One hawaiite flow from the 

upper member at an elevation of 457 m (1,500 ft) gave 

ages of 1.44-1.46 m.y., and two adjacent flows from the 

lower member at an elevation of 350m (1,150 ft) gave 

ages of 1.4 7 and 1.49 m.y. for the upper and lower flows, 

respectively. Extrapolations based on these ages indicate that the 490-m (1,610 ft) Kalaupapa section could 

have accumulated in as little as 0.05 or as much as 0.22 

m.y. If it is assumed that the section accumulated in 

about 0.14 m.y. (the average of the two extreme ages 

given above) and that there were 80 flows in the section, 

then the frequency of eruption was less than 2,000 

years. Further extrapolations based on the ages provided by McDougall (1964) indicate that the base of the 

section could be as young as 1.5 or as old as 1.65 m.y., 

though the maximum age is not tenable because the 

natural remanent magnetism polarity ofthe entire section is reversed (Sherman Gromme, Edward Mankinen, 

and Monte Marshall, oral commun., 1972). It is improbable that the Gilsa event of the Matuyama epoch (from 

1.64 to 1. 79 m.y., Cox, 1969), a period of 150,000 years, 

would not be recorded by flows erupting with a 2,000-

year frequency. The section was probably built in less 

than 0.22 m.y. ; this agrees with the work of McDougall 

(1964) and McDougall and Swanson (1972), who concluded that any of the volcanic edifices in Hawaii could 

have been built in 0.5 m.y. or less. 

Twenty-six samples from 24 flows were selected for 

detailed petrographic examination, whole-rock chemical analysis, and modal determination of phenocryst 
8 EAST MOLOKAI VOLCANIC SERIES 

content. Electron microprobe analysis of olivine, 

clinopyroxene, and plagioclase phenocrysts, chromite 

microphenocrysts, and olivine, clinopyroxene, plagioclase, and opaque-minerals in the groundmass was made 

on 25 of these samples. The 26 samples analyzed have 

been lettered from A to Z from the base of the section 

upward. The section is not continuously exposed. Several gaps are present in the record between flows A and 

B, E and F, and Q and R where one or more flows may be 

covered by talus. Most of the analyzed samples were 

taken from near the base of the flows. Two exceptions 

are sample G, taken from near the top of a flow about 

1.2 m (4ft) thick, and sample I, taken near the center of 

a flow about 9 m (30 ft) thick. Samples were analyzed 

from two horizons in two of the flows. These are samples 

Land M from near the base and top, respectively, of a 

flow about 9 m (30 ft) thick, and samples 0 and P from 

near the base and top, respectively, of a flow about 3.5 m 

(12ft) thick. 

One of the most striking aspects of the lavas in the 

Kalaupapa section, in comparison with alkalic basalts 

of most other Hawaiian volcanoes, is the abundance of 

plagioclase phenocrysts relative to augite and olivine. 

Most of the flows in the Kalaupapa section are porphyritic except for a few in the upper third of the section. 

The porphyritic flows commonly contain more than 20 

percent phenocrysts, but none in which modes were 

made contained more than 30 percent phenocrysts. This 

is contrary to the assertion of Stearns and Macdonald 

( 194 7) that augite phenocrysts are generally about 

equal in abundance or slightly more abundant than 

olivine and together constitute 40-60 percent of the 

rock. From the geometry of packing of equal-sized 

spheres alone, these abundances seem too high. For 

cubic open packing, the phenocryst content would be 52 

percent, and for cubic closed packing, it would be 74 

percent. If a lava contained 40-60 percent of phenocrysts, its mobility would be substantially reduced because the phenocrysts would be touching rather than 

free floating. 

The section studied was divided into a series of subsections on the basis of the whole-rock composition, but 

division on the basis of phenocryst content would have 

yielded the same subsections. Olivine phenocrysts are 

most abundant in the lower flows of the subsections, 

decreasing upward to almost zero in the uppermost 

flows of the subsections (fig. 5). In a broad way, the 

amount of augite phenocrysts decreases with the decrease in amount of olivine phenocrysts, but augite 

phenocrysts are usually only about a third as abundant 

as olivine phenocrysts. Of the 19 samples containing 

more than 5 percent phenocrysts, only one has appreciably more than a third as much augite as olivine 

phenocryst content; in it, augite is about 60 percent as 

abundant as olivine. The plagioclase phenocryst content does not vary with olivine content in as systematic 

a manner, although, in a very crude way, it does increase upward in both the entire section and the subsections. 

None of the flows in this section merit the designation 

of"ankaramite"2 as defined by LaCroix (1916), because 

the augite phenocryst content is not equal to, nor does it 

exceed, that of olivine in any of them, and plagioclase 

phenocrysts are abundant. 

Olivine phenocrysts almost invariably have deep-red 

to reddish-yellow alteration rims usually accounting for 

10-20 percent of the grain. These alteration rims follow 

the outline of the phenocryst even when it is strongly 

2 LaCroix defines a nkaramite as being"olivine-bearing and mclanocratic, rich in pyroxenes 

up to 1 em (0.4 in) in diamete r, and somewha t fewe r and smaller olivincs. The compact 

groundrna!::is is composed of large microlites of a ugite and tita nomagnetit e, a nd a littl e biotite 

and labra dori te" (lramdation from Johannsen, 1938). 

Olivine 

zf-:L-:~~~~.,.,-, 

y~.-=~~~~ 

)(. 

"' 

w 

v"":~~,.,.,.,.,,.,., 

~R 

tl. 

u 

~Q 

<l:p 

~0 

"' <l: 

a: N L.:.,.,.: : ,.,· ~,.,_,.,.,.,.,.,.,.,.,.,..,.,.,.,. 

tiM,:.: 

w L F"-'-'-'='-'='-'=-""""'-'-"' 

~K 

~ J _J 

~ I!=-'-~~="""" 

~Hf-=-~~~~~.,..,.,..,.,.,., 

~ G ~'-'-'-'-~~ ~~~--' _J 

~F 

<l: 

Clinopyroxene 

en E :::· 0~"-'-'-'-='-'~~~~~~ 

CF---'-'-.L-,~.,..,..,.,.., 

BF~~~~~ 

Plagioclase 

A~~~~L-~---L---L~~~~~---L---L __ -L___J 

0 5 1 0 1 5 20 0 5 0 5 1 0 1 5 20 

PHENOCRYST CONTENT, IN WEIGHT PERCENT 

FIGURE 5.- Histogram showing phenocryst content (in weight 

percent) of lavas of Kalaupapa section. Dashed horizontal lines 

separate eight subsections delimited on the basis of whole-rock 

chemistry. 
STRATIGRAPHY AND PETROLOGY 9 

resorbed and are nowhere truncated by a resorption Waikolu Valley provides further evidence of intratelsurface. Fresh growths of olivine over deep-red altera- luric alteration of olivine. Olivine phenocrysts near the 

tion rims and in optical continuity with the core are center of this dike are rimmed with fresh overgrowths, 

common (figs. 6A, B). These fresh overgrowths led but those phenocrysts in the chilled margin of the dike 

Stearns and Macdonald (1947) to suggest, and I concur, have no fresh overgrowths. Similar overgrowths have 

that the alteration wfls intratelluric after a period or been reported in the literature (Mahle, 1902; Ross and 

periods of resorption and preceding intrusion or extru- Shannon, 1925; Tomkeiff, 1934; Sheppard, 1962) and 

sion. A porphyritic dike observed near the head of have been ascribed either to selective alteration of a 

FIGURE G.-Photomicrographs of a resorbed olivine phenocryst from Kalaupapa section showing intratelluric 

alteration and fresh overgrowth. Olivine phenocryst is 

1.8 mm (0.07 in.) long. A. Plane light. B. Crossed nicols. 

shell of iron-rich olivine or to intratelluric alteration 

followed by regrowth after intrusion or extrusion. Microprobe analyses (presented in the section "Compositional Variation of Olivine") of many fresh olivine overgrowths show them to be invariably richer in iron than 

either the phenocryst core or the altered zone, and on 

the basis of this evidence, the selective alteration origin, 

in these lavas at least, is not tenable. It is possible in 

most samples to identify the intratelluric alteration 

even when it has been overprinted with later deuteric 

alteration or weathering. The intratelluric alteration 

product is deep red and forms a narrow rim usually 

surrounding the entire phenocryst (with or without the 

fresh overgrowth). It follows in detail the resorbed 

shape of the grain, with few incursions along fractures, 

and is quite sharp in its contact with fresh core of the 

phenocryst. By contrast the deuteric alteration product 

is reddish yellow to reddish brown and forms broad 

feathery incursions into the phenocryst although concentrated mostly along the edge of fractures. In vertically reflected light and at high optical magnification 

(about x 1,000), the intra telluric alteration rims show a 

higher reflectivity than either the unaltered cores or the 

overgrowths. This high reflectivity results from tiny 

highly reflecting grains dispersed throughout the alteration rim. Some of the grains (about 0.3-0.5 J.Lm in 

diameter) are optically resolvable, but apparently many 

more are too small tp be resolved with a x 100/1.30 NA 

oil immersion objective. Further evidence (presented in 

the section "Compositional Variation of Olivine") indicates that the intratelluric alteration product is dispersed hematite with some associated magnetitepyroxene symplectites rather than "iddingsite" 

(smectite-chlorite, Wilshire, 1958). 

Some of the phenocrysts have a complex history of 

growth, resorption, alteration, and regrowth. One 

phenocryst exhibits particularly well the stages: (1) 

growth, (2) resorption, (3) alteration (hematitic), (4) 

regrowth, (5) resorption, and (6) further alteration (hematitic) (fig. 7). Olivine phenocrysts showing more than 

one stage of growth that is interrupted by resorption or 

alteration, such as the one just described, occur sporadically. They coexist with the more common olivine 

phenocrysts showing only one stage of growth, indicating that at least two generations of olivine 
10 EAST MOLOKAI VOLCANIC SERIES 

FIGURE 7.- Photomicrograph of an olivine phenocryst 

from Kalaupapa section showing (1) growth, (2) resorption, (3) alteration (hematitic), (4) regrowth, (5) resorption , and (6) further alteration (hematitic). Olivine 

phenocryst is 1.8 mm (0.07 in.) long. Crossed nicols. 

are present in some of the rocks from the Kalaupapa 

section. 

Small chromite grains occur as inclusions in olivine 

phenocrysts and as separate microphenocrysts in the 

groundmass. These inclusions and the chemical trends 

in the subsections, outlined later, argue for coprecipitation of olivine and chromite from the basaltic magmas. 

A few black augite phenocrysts as large as 1 em (0.4 

in) long are present, but most are less than 0.5 em (0.2 

in). Most augite phenocrysts are euhedral, but some 

grains have been slightly resorbed, and some overgrowths may be present. Most augites have a thin 

purplish-brown rim that is richer in 'FeO' and Ti02 than 

the core. This rim also may include tiny groundmass 

minerals. The composition of the titaniferous rim is 

similar to that of the groundmass augite. Two small 

augite phenocrysts from different flows showed reversals of this general zoning trend, but because both of 

them show patchy, or hourglass zoning (Strong, 1969), 

the reversals may only be apparent, having resulted 

from an accident of crystal growth, and therefore have 

no bearing on compositional trends in the rest magma. 

Opaque inclusions, probably chromite, and inclusions 

of fresh to partially altered olivine are found in many 

augite phenocrysts. 

Most plagioclase phenocrysts are less than 0.5 em (0.2 

in) long, but a few are longer than 1 em (0.4 in). Most 

plagioclase phenocrysts have had as complex a history 

as olivine. In addition to normal and oscillatory zoning, 

they show healed fractures and patchy-appearing areas 

(figs. 8A, 8B) possibly due to remelting. Some grains 

show zoning that somewhat resembles the hourglass 

zoning of augite. 

Opaque inclusions, probably magnetite, are rather 

abundant in the plagioclase phenocrysts. They are 

faintly green only on the thinnest edges and appear as 

tabular bodies along planes parallel to (010) twin 

planes. In reflected light under high magnification, they 

seem to be concentrations of many tiny grains. Hightemperature disordered plagioclase can accommodate 

more iron, probably as Fe20 3, in its lattice that may 

exsolve at lower temperatures. Brown (1967) suggested 

that the exsolution may accompany inversion of 

plagioclase from one structural state to another. Poldervaart and Gilkey (1954) proposed that extraneous 

material may be introduced along minute surfaces of 

discontinuity, such as stacking faults, that are likely to 

FIGURE B.-Photomicrographs of a plagioclase phenocryst from 

Kalaupapa section showing tabular opaque (magnetite) inclusions oriented parallel to (010) twin planes. Plagioclase phenocryst is 4 mm (0.16 in.) long. A. Plane light. B. Crossed nicols. 

Note patchy zoning and healed fractures near lower left end of 

phenocryst. 
WHOLE-ROCK COMPOSITIONS 11 

occur in intermediate plagioclase. Because of its complex zoning, the average composition determined for 

plagioclase can be only approximate, in spite of the 

attempt to minimize the effects of zoning by scanning 

the beam during microprobe analysis. 

Benson and Turner (1940), quoted in Muir and Tilley 

(1961, p. 198), reported that the mugearites from Dunedin, New Zealand, contain 2 percent K20 but that no 

potassium feldspar is found in the groundmass and concluded that all the K20 may be in the plagioclase. Sample Z, also a mugearite, contains 2.05 percent K20 and is 

75 percent normative feldspar. The plagioclase in this 

sample contains 2.36 percent K20, and thus plagioclase 

accounts for about 85 percent of the K20 in the rock. 

There may be about 3 percent potassium feldspar in the 

groundmass, or more likely, the interstitial plagioclase, 

which was not analyzed, is more potassic than the distinct laths of plagioclase in the groundmass, which were 

analyzed. 

Plagioclase phenocrysts include olivine, some fresh 

and some partially altered, and augite. No plagioclase 

has been observed as distinct inclusions in olivine, 

though it may be partly intergrown with olivine. Few 

plagioclase inclusions have been found in augite. Augite and olivine apparently crystallized simultaneously, as each has been found as inclusions in the other. 

The general sequence of crystallization of phenocrysts 

seems to have been olivine, augite, plagioclase, with a 

period of augite growth overlapping that of olivine at an 

earlier stage of crystallization and that of plagioclase at 

a later stage. 

All the phenocryst minerals also occur in clusters, but 

their grain size is commonly, though not invariably, 

smaller than that of the discrete phenocrysts. Some 

olivine grains in the clusters are altered on all sides, 

even though they are partly enclosed by plagioclase or 

augite. By contrast, others are altered only on the side 

exposed to the magma. Fresh overgrowths, if present, 

occur only on the side of the olivine grain exposed to the 

magma. No fresh overgrowths have been observed on 

olivine grains that are included in augite or plagioclase. 

The aggregation of the minerals into clusters apparently took place both before and after intratelluric alteration of the olivine, but not after the fresh overgrowth 

was added. 

Opaque minerals also occur as microphenocrysts in 

these lavas. For the most part they are chromite similar 

in composition to the chromite included in olivine (see 

the section ~~compositional Variation of Opaque Minerals), but some of them are zoned continuously from 

chromite cores to ul vospinel rims. A discussion of these 

zoned oxides is beyond the scope of this paper. Anderson 

and Wright (1972) observed reversed zoning of oxides in 

some Hawaiian tholeiites (MgO and Cr20 3 increasing 

toward margins). They considered this as supporting 

evidence for mixing of magmas, one of which was more 

fractionated than the other. No such reversed zoning of 

chromite was observed in the Kalaupapa section. 

Cr20 3 shows a marked decrease upward in the subsections. Chromite contains the bulk of the Cr20 3 in the 

rock, and only 0.5 percent chromite could account for the 

maximum Cr20 3 content observed; therefore, no determination of the modal amount of chromite in the lavas 

was made, nor is Cr20 3 considered in the magnesium 

var.iation diagrams for phenocryst-free compositions. 

The groundmass of most samples of the lower member 

of the East Molokai Volcanic Series is holocrystalline 

and has an intergranular texture. Hypocrystalline 

patches occur near vesicles in some of these otherwise 

holocrystalline samples. The few samples that are 

hypocrystalline have intersertal textures. The major 

constituents of the groundmass are feldspar, 

clinopyroxene, and olivine. Stearns and Macdonald 

(194 7) reported the clinopyroxene in most samples to be 

pigeonite, but microprobe analysis shows them to range 

from subcalcic to calcic augite. Opaque minerals occur 

as well-defined equant to elongate grains of about 0.05 

mm (0.002 in). Microprobe analysis shows that both 

titaniferous magnetite and ilmenite are commonly 

present in the groundmass. Acicular apatite crystals, 

present in most of the samples, are especially abundant 

in flows in the uppermost parts of the subsections. 

The groundmass of most samples of the upper 

member of the East Molokai Volcanic Series has 

pilotaxitic to trachytic texture and an average grain 

size of about 0.04-0.1 mm (0.0016-0.004 in.). However, 

the lowermost sample from the upper member, sample 

X, has a subophitic texture and average grain size of 

about 0.15 mm (0.006 in). Major constituents of the 

lavas of the upper member are plagioclase (potassic 

andesine), olivine, and colorless to pale-purplish-brown 

augite. In some samples olivine is more abundant in the 

groundmass than is augite. Accessory minerals are 

acicular apatite, magnetite, and ilmenite. Tiny biotite 

grains were identified in one sample. 

WHOLE-ROCK COMPOSITIONS 

The whole-rock composition for each sample is given 

in table 1. Dry-reduced compositions were determined 

by recalculating total iron as ~FeO,' subtracting H20 

and C02 , and then normalizing to 100 percent. The 

dry-reduced compositions are used in all diagrams to 

facilitate comparison with the microprobe analyses of 

minerals from which Fe+2 and Fe+3 cannot be 

evaluated. 

All the lavas from the Kalaupapa section are 

hypersthene normative, and nine are quartz normative 

(table 1), possibly owing partly to oxidation during 
12 EAST MOLOKAI VOLCANIC SERIES 

weathering. However, no modal hypersthene (or 

pigeonite) was observed. None of the lavas from the 

Kalaupapa section are nepheline normative. 

A plot of the dry-reduced whole-rock compositions on 

a total alkali-silica diagram (fig. 9), the diagram that 

Macdonald (1968) considered to be the best criterion to 

separate rocks of the alkalic suite from those of the 

tholeiitic suite, shows that most of the samples plot in 

the alkalic field. Eight samples plot in the tholeiitic 

field, but petrographic criteria suggest that they are 

·alkalic. Because of this discordance between the petrologic classification and the chemical classification 

based on the total alkali-silica diagram, the whole-rock 

compositions were also plotted on an olivine, nepheline, 

silica ternary diagram (Poldervaart, 1964). On this 

diagram only three of the analyses plot in the tholeiitic 

field (fig. 10). Irvine and Baragar (1971) proposed new 

tholeiitic-alkalic boundary lines for both the total 

alkali-silica and olivine, nepheline, silica diagrams. By 

using their boundary lines, 16lavas plot in the tholeiitic 

field in the total alkali-silica diagram (fig. 9), and of 

these, 14 plot in the tholeiitic field in the olivine, 

nepheline, silica diagram (fig. 10). 

When the boundary lines proposed by Irvine and 

Baragar (1971) are used, the division of the rocks ofthe 

Kalaupapa section into tholeiitic and alkalic suites on 

the total alkali-silica and olivine, nepheline, silica diagrams is in good agreement. However, the Irvine and 

Baragar boundary lines increase the discordance beTholeiitic field 

40 45 50 55 60 

Si0 2 CONTENT, IN WEIGHT PERCENT 

FIGURE 9.-Total alkali-silica diagram of dry-reduced whole-rock 

compositions from Kalaupapa section. A-Z, samples from base of 

section upward. Solid arrows, trends of clinopyroxene (augite), 

olivine, and plagioclase compositions from base of section upward. 

Open triangle, clinopyroxene in a garnet clinopyroxenite xenolith 

( 68SAL--11) from Salt Lake Crater reported by Beeson and Jackson 

( 1970). Dashed arrows, nephelinic, alkalic, and tholeiitic trends and 

field boundary (solid line) from Macdonald (1968). Field boundary 

(dotted line) proposed by Irvine and Baragar (1971). 

Alkalic field 

Nepheline 

Olivine 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

IH 

I 

Ll 

I 

I 

lAMe 

jiYNE 

u I II x 1 T 

~s 

Q~ P I 

v I 

F ~ I 

I 

Tholeiitic field 

D 

Silica 

FIGURE 10.-0livine, nepheline, silica diagram of dry-reduced 

whole-rock compositions from Kalaupapa section. Solid line, field 

boundary proposed by Poldervaart (1964); dashed line, field boundary proposed by Irvine and Baragar (1971). A-Z, samples from base 

of section upward. 

tween the petrologic and chemical classification of 

Hawaiian basalts, and especially of basalts of the 

Kalaupapa section. The boundary lines proposed by 

Macdonald (1968) and Poldervaart (1964) are therefore 

preferred for Hawaiian basalts. A similar discordance 

between chemical and mineralogic classifications based 

on feldspar compositions was noted by Keil, Fodor, and 

Bunch (1972) in lavas from Maui, which they considered 

to be transitional between tholeiitic and alkalic suites. 

In general the basalts in the lower part of the 

Kalaupapa section defy a common chemical and petrologic classification and are better considered as transitional between tholeiitic and alkalic. 

The trend that the lavas from the Kalaupapa section 

define (fig. 9) is at a steeper angle to the alkalictholeiitic field boundary of Macdonald (1968) than is the 

general trend of Hawaiian alkalic lavas that he presented. Conservatively, the trend of the Kalaupapa 

lavas is about 30° to Macdonald's alkalic trend. It appears that there is less olivine control3 for the lavas of 

the Kalaupapa section than for the Hawaiian alkalic 

lavas in general and that the trend of the lavas is rotated toward Macdonald's nephelinic trend. Macdonald 

3Powers ( 19551 drew lines that he called "olivine control" lines, in an oxide-oxide diagram 

from plots of olivine phenocrysts into the field of basalts. These olivine control lines indicate 

the straight-line variation that would result from changing the amount of olivine in any 

plotted rock composition through which the lines are drawn. Comparable control lines can be 

drawn for other minerals. Wright (1971) noted that if more than one mineral controls the 

chemical variation, unique control lines cannot generally be defined. However, the sense in 

which deviations occur from lines that define dominantly a single-mineral control may 

indicate which additional mineral species is causing the chemical variation. 
WHOLE-ROCK COMPOSITIONS 13 

(1968) compared trends of alkalic and nephelinic lavas 

from Hawaii with experimental ones determined by 

Green and Ringwood (1967), pointing out that progressing from high to low pressures, the fractionation trend 

shifts from nephelinic through alkalic to tholeiitic 

trends of the Hawaiian suites. In terms of mineralogy 

and considering only Na20+K20 and Si02, the control 

shifts from clinopyroxene through orthopyroxene to olivine+ plagioclase. 

Figure 11 shows the Kalaupapa lavas on an AFM 

(alkali, iron, magnesium) diagram on which the general field of Hawaiian lavas has been outlined (Macdonald, 1968). The Kalaupapa lavas fall to the iron-rich 

side of the field but totally within it. The compositional 

range of olivine and augite phenocrysts from these 

lavas, indicated by arrows, shows that in an AFM diagram olivine control cannot be separated from augite 

control. It was shown earlier that the amount of augite 

phenocrysts varies directly with that of olivine, and this 

type of plot emphasizes the trend. 

It is apparent (fig. 11) that the fractionation trend 

does not progress continuously from ((primitive" lavas 

with a high MgO(FeO' ratio to a ((fractionated" lava 

with a low MgO(FeO' ratio going from flows A to Z, but 

rather several successive flows plot along a trend only to 

be interrupted by a discontinuity marking an abrupt 

increase in the MgO(FeO' ratio to start anew the fractionation trend. Also the talus-covered gaps discussed 

earlier must be considered when the fractionation pattern is being examined. 

F 

The section has been divided into several subsections 

on the basis of where abrupt increases in the MgO(FeO' 

ratio occur. The subsections that have been delimited 

are A, BCD, EF, GHIJK, LMNOP (Land M, and 0 and P 

are samples from different levels of two flows), QRS, 

TUVW, and XYZ. The gap between A and B is considerable, and so A must stand alone as a subsection. A small 

gap between E and F leaves only two samples in this 

subsection. The samples in subsection QRS show very 

little variation and conceivably represent surges of the 

same flow. Subsection XYZ has a discordance at Y 

marking a regression from hawaiite back to alkalic 

basalt and probably represents segments of two subsections. This regression is significant because it shows 

that regression to more ((primitive" lavas can occur in 

all stages of fractionation and not only within the fields 

of transitional and alkalic basalts. 

In an approximate way, the lowermost flows of the 

progressively higher subsections are more fractionated 

than those of the lower subsections; also the uppermost 

flows of the progressively higher subsections are more 

fractionated than those of the lower subsections. The 

fractionation pattern is thus one of several steps forward and a jump back, starting at rocks transitional 

from tholeiite to alkali olivine basalt and culminating 

in mugearite. 

Magnesia variation diagrams of dry-reduced wholerock compositions (fig. 12) give some idea as to what 

minerals control the fractionation. The minerals that 

occur as phenocrysts (olivine, augite, and plagioclase) 

control the major elements, especially in the lower part 

of the section. The abrupt drop of (FeO' and Ti02 in 

sample Z indicates control by ilmenite or ulvospinellate 

in the section. Chromite, which occurs as inclusions in 

olivine and as microphenocrysts in the groundmass, 

controls the Cr20 3 content almost entirely. The subsections that were delimited from the AFM diagram 

correspond precisely to those delimited from magnesia 

variation diagrams on the basis of the elements that 

typically are used as fractionation indicators, that is, 

Na20, K20, and Ti02 as well as Cr203 and NiO. 

Variation diagrams have been criticized as indicators 

of fractionation in recent years, especially by Chayes 

(1971). Each oxide in the analyses was therefore plotted 

against relative stratigraphic position (fig. 13) to bypass 

the ((closure restraint" discussed by Chayes. In the subsections, Si02, Al20 3, Na20, K20, Ti02, and P20s increase rather consistently and sometimes dramatically. 

A.'----"'----"'--___.._--"----'"---..l<.---><----->L..---"'-----"M If an en vel ope were drawn to include all the analyses, it 

FIGURE 11.-AFM diagram of dry-reduced whole-rock compositions 

from Kalaupapa section. Outlined area, field of Hawaiian basalts 

(Macdonald, 1968). A-Z, samples from base of section upward. Arrows, compositional range of olivine and clinopyroxene (augite) 

phenocrysts from base_ of section upward. 

would show that there is a general increase of these 

oxides up the entire section, substantiating the conclusion, indicated by the AFM diagram (fig. 11) that the 

subsections become progressively more fractionated up 

section. 
14 EAST MOLOKAI VOLCANIC SERIES 

1-

z 

w 

u 

a: 

w 

0.. 

1-

I 

~ 

w 

~ 

~ 

,_-

z 

w 

1-

z 

0 

u 

w 

0 

x 

0 

40 I I I I I 

-

~ 

30 Ill 

u 

0 

"60 

Ill 

Y=M and N s:: 

"' 

~20 -

~ 

0 

Ill 

u 

wz 

FQ/KPVO 

c I RD 

HGBY ~JU 

E L 

10 f- - ~'Q 

~'Q 

0~ A/ 

Olivine 6"~ 0 

~'Q 

~'Q (,.0 oo/ 20 6"~ 

15,... 

C=A ~ I=F Ill 

L=B !! Y=M and N T D Ill 

10 HGLY CJ I K S::- E U QR v SXPW 0 

5 

Olivine o~==r===r=~~~--~--~--~--~L_ __ L__j 

40 30 20 

MgO 

10 0 

0 

Cl) 

~ 

0 

Ui 

20 

~ ' -

15 - C=A 

Y=M and N 

R=X 

u 

T I S BY J QRXO 

HL c F DKP 

E G vw 

10 

5 

~ - §' 

t' f) 0 

·$ (J - ~ 

"' Ill 

u 

0 

0 £• 

55 f- I=F ~ Ill 

S=R 

V=O 

Y=N 

50 f- ' 

u 

0 

z"!iO Ill 

;L. s:: ..... 

0 D ~ K~W 

~ c s A J I X GY T Q 

E HLM u B 45,... 

40 f-

~~in~ ~ 

35L---~--~----~'----~--~----L---~--~--~ 

40 30 20 

MgO 

10 0 

OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 12.-Magnesia variation diagram of dry-reduced whole-rock compositions from Kalaupapa section. A-Z, samples from base 

of section upward. Italicized symbols indicate coincidence of two ~r more points. Coincident points shown in left part of each 

diagram. Arrows, ranges in olivine, plagioclase, and clinopyroxene (augite) compositions from base of section upward and are 

not to be confused with "control lines." 

In a similar manner, three oxides (MgO, NiO, and 

Cr203) decrease upward in both the subsections and the 

whole section. NiO and Cr20 3 may show as much as a 75 

percent decrease from the lower to upper flows in a 

subsection. NiO and Cr20 3 in these lavas are very sensitive indicators of fractionation involving olivine, in 

which most of the NiO resides, and chromite, in which 

most of the Cr20 3 resides. The close parallelism in variation of these two oxides indicates coprecipitation of 

chromite and olivine in early stages of fractionation. 

Because of the close relation between the variation of 

the phenocryst content and the compositional variation 

of the lavas, it is important to examine the compositional variations of the lavas with the contribution 

made by phenocryst content removed (phenocryst-free 

compositions) to see if any significant compositional 

variations in the lavas are masked by phenocryst concentrations. 

PHENOCRYST -FREE COMPOSITIONS 

The phenocryst compositions can be effectively subtracted from the whole-rock compositions with magnesia variation diagrams (Powers, 1955) if the only 

phenocryst mineral in the lava is olivine. The lavas 

from the Kalaupapa section, however, contain as many 

as three kinds of phenocrysts, and they cannot be so 

conveniently removed diagrammatically. The phenocrysts therefore were subtracted from the dry-reduced 

whole-rock composition on the basis of their modes and 

compositions. 
PHENOCRYST-FREE COMPOSITIONS 15 

Q 

~z 

z 

w 

u 

a: 

w 

Q.. 

~ 

J: 

(!) 

I=F 

L=B 

S=R 

.2 V=O 

Y=M 

.1 rI I I I E 

HG 

N 

I I 

1.0 -

I=F 

0 S=R 

a.." Y=N 

- .5 rOlivine 

0 

2 1-

I I I I I I 

z -

PO 

u X VW 

QSK -

M A J I D ~ ~ LY CT u HGB 0 

E "bh 

Clinop~xene ~ 

~ 

z -

~ LY l ~ 0 

~ AJUIQ g ~ 

S=R 

N=M 

SD "b'o ~- Clinop-yroxene X:Kwwz !3 

~ 0 1---------------==------~ll.. 

~ ? z 

0 

u 

w 

o 3 r- N=M 

X 

0 

1 rQ) 

Q 

SX 

UI RKVW 

J D 

L N AT 

BY C 

F 

~ HG 

E~ 

~ 0. 

0 

.s 

fJ 

~ ~ 

u 

0 

"b'o 

Olivine ~ 

oL-==~===c~~--L--~--L-~--L_~~ 

45 40 35 30 25 20 15 10 5 0 

MgO 

0 

.. lQ 

z 

-

0 

4 1-

2 1-

0 

45 

Olivine 

S=R 

V=O 

Y=N 

Olivine 

40 35 

PO xvw u QSK Q) 

LN F D il y AT J I 

Clinopyroxin5,. HGB c ~ 

~ 

z 

Q) 

<I> 

~ 

u 

0 

PVW·~ 

XK E:: VFQS 

A I D LY M CT HGB -

E ~e. ~e. ~0 ~.., 

I c'\."-~0/ I I 

30 25 20 15 10 5 0 

MgO 

OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 12.-Continued. 

Compositions and normative minerals of these 

phenocryst-free lavas are given in table 2. The total 

alkali-silica diagram for phenocryst-free compositions 

(fig. 14) shows that six of the samples plot in the tholeiitic field as compared to eight in the corresponding 

whole-rock diagram (fig. 9), and most of these six samples have shifted toward the field boundary line of Macdonald (1968). It is significant that the data show less 

scatter than in the whole-rock diagram and the trend is 

at a steeper angle to the alkali trend (rotated more 

toward the nephelinic trend) of Macdonald than the 

trend of the whole-rock compositions. The trend of the 

phenocryst-free compositions can be attributed almost 

entirely to variation in the amount of clinopyroxene in 

the lavas and shows little or no olivine or plagioclase 

control. The AFM diagram (fig. 15) shows that the 

phenocryst-free compositions, like the dry-reduced 

whole-rock compositions, plot toward the iron-rich side 

of the field of Hawaiian rocks as given by Macdonald 

(1968), with only two falling just outside of this field. 

Removal of the phenocrysts has not produced any rock 

compositions for which there are no natural counterparts in Hawaiian lavas. The main effect of phenocryst 

removal has been to shorten the range of MgOfFeO' 

ratios from the high side (compare fig. 11 with fig. 15). 

This is expected because the part of the trend in the 

AFM diagram (represented by these compositions) results mainly from augite plus olivine control, and 

phenocrysts of these two minerals have been removed. 

The magnesia variation diagrams for phenocryst-free 

compositions (fig. 16) provide a more complete picture of 

how removal of phenocrysts has affected the lavas (compare the dry-reduced whole-rock magnesia variation 

diagrams (figs. 12, 16) ). Both Si02 and Al203 exhibited 
16 

z 

0 

i= 

(/) 

0 

a.. 

~ 

l: 

a.. 

<( 

a: 

(!) 

1-

<( 

a: 

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w 

> 

i= 

<( 

...J 

w 

a: 

z 

(/) 

w 

...J 

a.. 

~ 

<( 

(/) 0 

z 

0 

1-

(/) 

0 

a.. 

~ 

l: 

a.. 

<( 

a: 

(!) 

1-

<( 

a: 

1-

(/) 

w 

> 

i= 

<( 

...J 

w 

a: 

z 

(/) 

w 

...J 

a.. 

~ 

<( 

(/) 

z 

0 

1-

(/) 

0 

a.. 

u 

l: 

a.. 

<( 

a: 

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1-

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a: 

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w 

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1-

<( 

...J 

w 

a: 

z 

(/) 

w 

...J 

a.. 

~ 

~45 

EAST MOLOKAI VOLCANIC SERIES 

___ y ){__ __ 

T 

w 

v 

u 

--s---- R 

__ g__ __ _ 

H 

G 

N 

M 

K 

p 

0 

-~----

_---,::) E ___ _ c 

~-----

A 

.1 .2 

MnO 

y ____ .lS._ ___ _ 

u 

w 

v 

____ Q_-p---

0 N 

M 

-~-------

w 

v 

2 

s---

R 

p 

0 

---

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A 

3 4 5 

y .,.lL __ 

w 

v 

_u2.__ 

p 

0 

N 

M 

_!::..___ 

K 

H 

_ ____9_ 

A 

0 .1 

NiO 

v 

__ u _2_ ___ _ 

s 

R 

K 

J 

___ H Q__ __ _ 

F 

__ c __I! ___ _ 

0 

A 

.2 

_ ____ x_ 

w 

v 

u ___ _r_-s--

_____ Q_ 

H 

G 

N 

M 

----~=--

E ----~-

__ c __~~. __ _ 

A 

2 2 4 

A 

10 15 20 10 15 0 10 

A1 2 0 3 'FeO' MgO 

20 5 10 

CaO 

OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 13.-Weight percent of oxides in dry-reduced whole-rock compositions from Kalaupapa section plotted against relative stratigraphic position. A-Z, samples from base of section upward. Dashed horizontal lines, subsections delimited on basis of abrupt 

increase in ratio of MgO/'FeO' and phenocryst content (fig. 5). 
1-

2 

w 

u 

(( 

w 

a.. 

II 

(!) 

8 

7 

6 

Alkalic field 

PHENOCRYST-FREE COMPOSITIONS 17 

in the whole-rock magnesia variation diagram (fig. 12) 

all form trends indicating control by one or more of the 

~~// phenocryst minerals, olivine, clinopyroxene, or plagio-

....... ~/ clase, with olivine generally dominating. The abrupt 

'*~"'/ ?::J.'b>-..-1 decrease in (FeO' and Ti02 in the uppermost flows indi-

''% v ~ "()o-»~ c'-'?J.<:>~ cates late-stage fraction of ilmenite, ulvospinel, or other 

,;o-:$ U o/O ?::,. \0 

' 19/.· x -...~" <i?.'-?>4 Fe-Ti oxides. The trends of the phenocryst-free composi- '(~~· ~ K ~ 

'~~ / tt~A tions for (FeO,' CaO, Na20, K20, P20 5, and Ti02 (fig. 16) • + 4 

~ 0 

~ z> '~~Q' / fy o leave little doubt that clinopyroxene is the dominant 

/

' ~~~ Tholeiitic field controlling mineral, except the late decreases in (FeO' 2 

8 2 E and Ti02• It is significant that the trends for ~FeO,' CaO, w 

0 

X 

0 

Clinopyro K20, and P20 5 in particular are at high angles to what 

Oliv ~ne they would be if olivine were the controlling mineral. QL---~~------L-----~------~----~----~ 

35 40 45 so 55 60 65 The narrowness of the trend defined by these elements 

Si02 

oxiDE coNTENT, IN WEIGHT PERCENT indicates that there is very little residual olivine control 

FIGURE 14.-Total alkali-silica diagram of phenocryst-free compositions from Kalaupapa section. A-Z, samples from base of 

section upward. Solid arrows, trends of olivine, clinopyroxene 

(augite), and plagioclase from base of section upward. Open 

triangle, clinopyroxene in a garnet clinopyroxenite xenolith 

from Salt Lake Crater reported by Beeson and Jackson (1970). 

Field boundary from Macdonald (1968). 

F 

in spite of the possible additive errors in the modes and 

microprobe analyses. 

Variation in NiO and Cr20 3 content are completely 

controlled by olivine and chromite, respectively, and 

therefore need not be considered in the phenocryst-free 

compositions. 

Stearns and Macdonald (1942) envisioned a magma 

body beneath Hawaiian volcanoes that is .zoned from 

hawaiite at the top to picrite at the bottom. Differentiation in the magma body was considered by them to be 

primarily the result of settling of olivine, clinopyroxene, 

and plagioclase, aided by volatile transfer of certain 

substances (particularly the alkalies) to the upper part 

of the magma body. Tapping of the magma body at 

different levels would yield magmas of different compositions and phenocryst contents. Murata and Richter 

(1966a, b) showed for the 1959-60 Kilauea Iki eruption 

that the olivine phenocryst content of the erupting lavas 

was directly related to the rate of discharge. They 

suggested that strong currents of magma erode beds of 

previously sedimented olivine crystals lying on the bottom of the magma chamber. In both the Stearns and 

Macdonald (1942) and the Murata and Richter (1966a, 

b) models, fractionation occurs in a shallow magma 

AL---lL--~-...lL--~-.......lL..---l.L-----lO~---l"---lL-~M chamber. The phenocryst content of the lavas depends 

FIGURE 15.-AFM diagram of phenocryst-free compositions from 

Kalaupapa section. A-Z, samples from base of section upward. 

Outlined area, field of Hawaiian basalts from Macdonald (1968). 

Arrows, compositional range of olivine and clinopyroxene (augite) 

from base of section upward. 

on the level at which the magma chamber is tapped or 

on the rate at which it is discharged. In either case, 

mechanical processes can introduce chemical variation 

in the lavas that masks more subtle, but possibly more 

significant, chemical variation. Subtraction of the 

phenocrysts from the lavas in the Kalaupapa section 

marked olivine control in the whole-rock lavas, but re- has, to a first approximation, removed compositional 

moval of the phenocrysts has telescoped the trend to variation resulting from shallow fractional crystallizasuch an extent that it ceases to exist, leaving a trendless tion, the rate of discharge, and postextrusion settling of 

cluster of points. Thus any systematic variation in Si02 phenocrysts. The compositional variation of the 

and Al20 3 in the whole-rock chemistry is primarily the phenocryst-free lavas allows us to discern an earlier 

result of the relative amounts of phenocrysts, especially fractionation event, one that occurred before fractional 

olivine, in the lavas. 1 crystallization in the shallow magma chamber. At preThe contents oCFeO', CaO, Na20, K20, P20 5, and Ti02 1 sent there is no evidence to suggest whether the earlier 
18 EAST MOLOKAI VOLCANIC SERIES 

I 

30 

"' '!_ 20 r- H=G 

<( N=M 

1-

z 

w 

u 

a: 

w 

0. 

1-

J: 

C) 

w 

3: 

~ 

j-:' 

z 

w 

1-

z 

0 

u 

w 

W=U and P 

Y=A 

10 r- S=F 

Olivine 

25 r20 F=D 

M=H 

N=G 

E=R and Q 

0 15 

x~ Ou 

10 

5r 

Olivine 

I I I I I 

z HTXI EBNSQO 

CLJRYKW DV 

-

-

-

-

Q~==c===c=~L_I __ L_I __ L_I __ L_ __ L_I __ L___j 

45 40 35 30 25 20 15 1 0 5 0 

MgO 

0 

II) 

u. 

~ 

0 

15 r- N=M and H 

R=D 

W=V 

Y=A 

10 r5 rI I I I I 

w 

S DO 

-J~~KPL 

CL YX 

N E G 

cu 

<I) 

t) "' 

0 

"60 

£• 0~----------------------------------~ 

55 

50 

M=J and F 

N=H 

W=V 

S=R 

D 

CGAKPO 

E&~TXWl B QU 

Cii 45- -

40 -

35~--~~--~~--~'--~'--~'~--~'--~'--~'--~ 

45 40 35 30 25 20 15 10 5 0 

MgO 

OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 16.-Magnesia variation diagram of phenocryst-free compositions of Kalaupapa section. A-Z, samples from base 

of section upward. Italicized letters indicate coincidence of two or more points. Coincident points are shown in left 

part of each diagram. Arrows, ranges of olivine, clinopyroxene (augite), and plagioclase from base of section upward 

and are not to be confused with "control lines." Open triangle, clinopyroxene in a garnet clinopyroxenite xenolith 

from Salt Lake Crater (Beeson and Jackson, 1970). 

fractionation event involved fractional fusion or fractional crystallization. However, it is evident from the 

variation shown in the phenocryst-free compositions 

that the mineral controlling the earlier fractionation 

was aluminous clinopyroxene. 

It should not be inferred that the phenocryst-free 

compositions represent primary lavas. The primary 

lavas are almost certainly richer in magnesia than 

these (Wright, 1971). It is clear, however, that most of 

the compositional variation imposed on the lavas by olivine fractionation was removed in the calculation of 

phenocryst-free compositions. 

Beeson and Jackson (1970) showed that the 

.nephelinic suite on Oahu, the Honolulu Volcanic Series, 

could have been derived by partial fusion of a garnet 

pyroxenite at a depth of about 100 km and that clinopyroxene would be the last mineral to melt. The lavas in 

the Kalaupapa section may also be the product of fractional fusion of a garnet pyroxenite. If all minerals in 

the garnet pyroxenite except clinopyroxene were entirely melted, then the trends in the phenocryst-free 

lavas could be produced by the varying amounts of the 

clinopyroxene that is melted. Clinopyroxene from a 

garnet pyroxenite parent would be considerably more 

aluminous than the phenocrysts; in fact the lack of a 

trend of Al20 3 and Si02 (fig. 16) demands that the Al203 

and Si02 content of the controlling clinopyroxene approach that of the lavas. The composition of 

clinopyroxene from a garnet pyroxenite xenolith from 

Salt Lake Crater, Hawaii (Beeson and Jackson, 1970), is 

plotted in figure 16. Except for Na20, it falls between 

the composition of the clinopyroxene phenocrysts and 

that of the phenocryst-free lavas. Clinopyroxenes, such 

as the ones analyzed from Hawaiian garnet pyroxe-
PHENOCRYST-FREE COMPOSITIONS 19 

1-

z 

w 

u 

a: 

w 

Q.. 

1-

I 

~ w 

~ 

~ 

..: 

z 

w 

1-

z 

0 

u 

w 

Cl 

Q 

z 

.2 

.1 rH=G 

S=D, F, and R 

X=K 

Y=A 

W=V and P 

I I I 

-

~ E cC 

'U HT O 

C NSQ "b'o 

Clinopyroxene 1 xwoz !! 0~-------------------------=2--~--~B~LM~ru~I-~~ 

4-

N=M and J 

Y=A 

v 

w 

u 

PO Q I 

K 

X 

s BNRT 

LD 

-

~ 3 

FY 

H C G 

-

.. 0 

i= 

E 

2 r1 r--

<U-

<ll 

~ 

'() 

0 

"b'o 

Olivine ce OL_==~====±~~L_I __ ~ ___ L_I __ ~I ____ ii ____ L_I~~~ 

45 40 35 30 25 20 15 1 0 5 0 

MgO 

1.5 

"' 0 

.. Q.. 

0 

-1 

0 

... 

Ill 

z 

r- H=G 

N=J 

S=R 

T=A 

.5 rOlivine 

0 

2 - F=D 

0 

4 r2 

0 

45 

N=M 

S=R 

T=A 

W=P 

Olivine 

H=G 

M=J 

S=R 

V=U and P 

Olivine 

40 35 

I I I I I 

-

z 

v 

w 

u 

PO 

X 

MQKI 

s LNFT ~ DY cC 

CBH '() 

E 0 

"b'o 

~ 

Clinopy~ene ~ 

z 

v 

wo 

u 

LNlK ~ y 

11 F 

T J I G 

BH 

Clinopy.loxene Ec ~ 

z 

~ ~ 

'U 

0 vo "b'o xw cC FQK 

MSA I ~ LNY !::. 8 HDT 

c 

E -

~'lJ j.'lJ 

"'0 o-q4. 6-$>7 I I I 

30 25 20 15 10 5 0 

OXIDE CONTENT, IN WEIGHT PERCENT MgO 

FIGURE 16.-Continued. 

nites, may be responsible for the variations seen in the 

phenocryst-free lavas. 

Green (1971) devised a petrogenetic grid from which 

pressures of origin and degrees of partial melting of 

mantle-derived basalts can be determined from magma 

compositions. This grid shows that alkali olivine basalt, 

such as that in the Kalaupapa section, could originate 

from 10 to 20 percent partial melting of this pyrolite 

mantle at depths of 45-60 km (23-37 mi) and that clinopyroxene would be a residual phase (along with olivine) 

remaining after extraction of the magma. 

As an alternative to the fractional fusion hypothesis, 

the compositional variation could result from the fractional crystallization in a deep (45-75 km, 28-46.5 mi) 

magma chamber in which clinopyroxene could be a 

liquidus mineral (Green and Ringwood, 1967). The 

composition of the liquidus clinopyroxene would probably be similar to that from the garnet pyroxenite described above. My evidence does not discriminate between fractional fusion or fractional crystallization. 

A necessary product of fractional crystallization of 

the lava at pressures of 15-25 kilobars would be clino- · 

pyroxene cumulates on the floor of the magma chamber, 

and later eruptions probably would incorporate fragments of the clinopyroxene cumulate and transport 

them to the surface where they would be found as xenoliths. The work of Jackson (1968), however, shows a 

decided lack of clinopyroxene cumulate xenoliths from 

the alkalic lavas of Hualalai and Mauna Kea. Many of 

the wehrlite xenoliths from these lavas, however, contain abundant veins of clinopyroxene, and some of the 

wehrlites appear to have been soaked in clinopyroxene. 

The possibility therefore exists that the clinopyroxene 

cumulates could have been destroyed by a metamorphic 
20 EAST MOLOKAI VOLCANIC SERIES 

event. On the other hand, Hualalai has not yet reached 

the stage of eruption that the Kalaupapa section represents, and clinopyroxene xenoliths therefore should not 

necessarily be expected. Neither East Molokai Volcano 

nor Kohala Volcano on the island of Hawaii, which are 

more like each other and less like some of the other 

Hawaiian volcanoes, contain many xenoliths. It might 

therefore be argued that they are unique and an absence 

of xenoliths is characteristic of them. 

Many of the lavas in the southwestern United States 

(Wilshire and others, 1971), Australia (Binns, 1969; 

Binns and others, 1970), and Hawaii (observed by me) 

that contain ultramafic xenoliths also contain black, 

aluminous, iron-rich clinopyroxene megacrysts. There 

is no great difference between the composition of these 

magacrysts and the clinopyroxene from the garnet 

pyroxenite xenolith (68SAI.r-11) described by Beeson 

and Jackson (1970). Both are thus prospective products 

of deep fractional crystallization. 

Murata (1960) indicated that fractional crystallization of clinopyroxene appears to be the principal 

mechanism by which tholeiitic magmas are converted 

to alkalic magmas. Yoder and Tilley (1962), though 

recognizing the importance of pyroxene fractionation, 

objected to Murata's scheme and example. Later Tilley 

and Yoder (1964) proposed a npyroxenite stage" in 

basalt genesis, suggesting that at pressures corresponding to upper mantle conditions, extraction of orthopyroxene and clinopyroxene from an olivine-rich 

tholeiitic liquid leads to the generation of an undersaturated residual liquid of alkali olivine basalt. 

The lavas in the Kalaupapa section range from 

basalts transitional between tholeiitic and alkalic to 

basalts that are unquestionably alkalic. Clinopyroxene 

clearly exhibits marked control in the fractionation of 

these lavas, but whether the transitional lavas were 

derived from a tholeiitic parent by clinopyroxene fractionation alone is an open question. Certainly desilication of a tholeiitic magma to produce the transitional 

basalts could not have been accomplished by fractionation of clinopyroxene, because the silica content of the 

controlling clinopyroxene is very near that of the transitional and alkalic lavas. If desilication is necessary to 

derive an alkalic magma from a tholeiitic one, then 

another mineral (possibly orthopyroxene) or a different 

mechanism must be sought to accomplish it. 

Removal of the phenocrysts has allowed us to look 

back beyond the fractional crystallization in a shallow 

chamber to a fractionation event controlled by clinopyroxene. If we concede that an alkalic lava may be derived from a tholeiitic parent magma through a process 

involving desilication, then there must be a fractionation event farther removed from the ones we have been 

able to define. If, on the other hand, alkalic magmas 

have been derived by fractional fusion of some primary 

mantle material, then we have identified clinopyroxene 

as the mineral controlling the compositional variation 

during partial fusion. If a magma produced by partial 

fusion of a garnet pyroxenite is fractionated at a depth 

at which clinopyroxene is the liquidus mineral, then 

little disturbance of the trend will occur because 

aluminus clinopyroxene would be the controlling mineral in both events. 

Now that it has been established that the Kalaupapa 

section can be divided into subsections either chemically or petrographically on the basis of phenocryst content and that much of the chemical variation can be 

attributed to phenocryst content, the question arises as 

to how the subsections originated. Powers (1955) proposed a ~~batch" concept for explaining the difference 

between historic and prehistoric tholeiitic lavas of 

Kilauea and Mauna Loa. Wright and Fiske (1971) confirmed and further refined the batch concept for the 

tholeiitic lavas of Kilauea. They identified three groups 

of summit lavas from Kilauea (pre-1750, 1750-1895, 

and 1911-present day) that can be distinguished chemically with little overlap. They also show on a lesser scale 

that each Kilauean summit eruption in the 20th century as a chemistry that is distinctive with respect to the 

chemistry of every other summit eruption. Briefly the 

batch concept supposes that magma is generated in the 

mantle on an episodic rather than a continuous basis 

and that each batch has a characteristic composition. It 

is suggested here that the subsections delimited in the 

Kalaupapa section may represent batches of magma 

injected into the rift zone and subsequently fractionally 

crystallized and erupted and that the batch concept is 

applicable to alkalic as well as tholeiitic Hawaiian 

lavas. 

Because much of the compositional variation in each 

subsection can be attributed to phenocryst content, it is 

necessary to evaluate how removal of the phenocrysts 

affects the interpretation that subsections are the expression of magmatic batches. This can best be seen in 

figure 17, in which the phenocryst-free compositions are 

plotted against relative stratigraphic position. Several 

oxides, Si02, Al20 3, and MgO, that show especially 

strong subsection variation in the whole-rock compositions (fig. 13) show little variation in the phenocrystfree compositions (fig. 17.) All these oxides are especially sensitive to olivine control, and Al20 3, to plagioclase control. In the whole-rock compositions (fig. 13), 

~FeO' shows little subsection variation but in the 

phenocryst-free compositions (fig. 17) shows distinct 

subsection variation. Subsection variation of Na20, 

K20, and P20 5 in the phenocryst-free compositions (fig. 

17) is nearly the same as it is in the whole-rock compositions. Two oxides, MnO and CaO, that show almost no 
MINERALOGY 21 

A 

---'l---

op N 

----x~-

__ ~ _G.__ 

F __ ____E. _ 

_ _oSi__ 

A 

45 50 10 15 20 10 15 10 5 10 15 

Si0 2 AI,03 'FeO' MgO CaO 

Z I y I Z y I Z Zy g __ ____A:w---- __ _x_ __ l--___ _x__ 

iii v YJ YJ ~ u u u 

-~~----~~~----~-~- ~ R R R 

iE 

<( 

~ __ _Q_p ___ --~-- ____ _Q._ps N 0 NO N 0 

~ _J ______ ~ _____ J __ _ ~ K K K 

j: { I J I 

<( H H H g _ ___..ll--,;---- .... : . .9--,;--- _..Jl.._T __ 

z E E E 

~ cB-u-===== l

15

=== =·=_i_ ---u== ~ 

<( 

<ll 1 A A 1 1 A 1 

Na2 0 

I 

~ 

g --~--

<( 0 a: N 1- M <f) __ .....L....... __ _ 

~ K j: J 

~ H w __ Q__ __ _ 

a: F 

~ _ ____E ___ _ 

<ll D ~ c ~ __ !L_ __ _ 

<( 

<f) 

0 .5 

P2 0, 

.1 

K 2 0 

.2 

MnO 

.3 0 

OXIDE CONTENT, IN WEIGHT PERCENT 

Ti02 

.1 

NiO 

.2 

FIGURE 17.-Weight percent of oxides in phenocryst-free compositions from Kalaupapa section plotted against relative stratigraphic position. Dashed horizontal lines, subsections delimited on basis of abrupt increase in ratio of MgO/'FeO' of 

whole-rock compositions (fig. 13) and phenocryst content (fig. 

5). A-Z, samples from base of section upward. 

variation in the whole-rock compositions (fig. 13) show 

marked subsection variation in the phenocryst-free 

compositions (fig. 17). CaO variation in the phenocrystfree compositions is the result of its concentration in 

clinopyroxene, which controls compositional variation 

in the phenocryst-free lavas. It is not obvious why MnO 

shows so little variation in the whole-rock compositions 

but does show marked variation in the phenocryst-free 

compositions. MnO, unlike CaO, is not concentrated in 

clinopyroxene; instead, like NiO, it is concentrated in 

olivine. Nonetheless, discontinuities in the MnO variation delimit the same subsection as do variations in the 

whole-rock compositions and the phenocryst content. 

Likewise, the CaO variation in the phenocryst-free 

compositions defines the same subsections; each subsection starts at the higher CaO contents and decreases 

upward in the subsection, then abruptly increases at the 

base of the following subsection. The distinct subsections, and accordingly the batches, can be seen in the 

phenocryst-free compositions as well as in the wholerock compositions. 

No modes were made for the chromite microphenocrysts because, judging from Cr20 3 content of the lavas, 

less than 0.5 percent of chromite would be present. As a 

result, variation ofCr20 3 has not been considered in the 

phenocryst-free compositions. 

MINERALOGY 

COMPOSITIONAL VARIATION OF OLIVINE 

Olivine occurs in the Kalaupapa lavas as phenocrysts, in clusters (usually of smaller grain size than the 

phenocrysts), in the groundmass, and as fresh overgrowths mantling altered olivine grains. The analyses 

of olivines are given in table 3, and the analyses for 

alteration rims of olivine are given in table 4. During 

the electron microprobe analysis of the phenocrysts and 

clusters, the electron beam was scanned rapidly over a 

lOx lO,um area to help even out inhomogeneities and to 

obtain, as nearly as possible, an average composition. 

No special attempt was made to avoid tiny inclusions or 

microfractures that may have trapped polishing compound (alumina), and as a consequence the values for 

Al20 3 are on the order of .OX rather than nearly zero as 

Smith (1966) and Simkin and Smith (1970), among 

others, have shown for most olivines. The Al20 3 values 

for olivine in no way affect the conclusions reached in 

this paper. 

The plots of CaO, MnO, NiO, and Ti02 versus (FeO' 

(fig. 18) and the plots of olivine composition versus relative stratigraphic position (fig. 19) show that composition does not differ consistently in the central part of the 

phenocrysts, the rims of the phenocrysts, or in the 

olivine of the clusters.4 The few grains identified opti4 In the remainder of this report, the description of olivine phenocryst compositions also 

applies to the olivine of the clusters. 
22 EAST MOLOKAI VOLCANIC SERIES 

-Br-----.------.~------,~------,~------.-~-----.------. T I I I I 

c} 

g og oo .3 1- go oogo 

.6 f- go -

~-4- u 

1-

~ .21-

u 

a: 

w 

0.. 

p g r 

r r grppcrp 

ppcppp P r r p r g 

r P P epp 

p p 

c p r 

c 

gg 0 

0 00 0.2f-

_i= 

.1 

-

p p p 

g gg c c r p 

r p p p r r r P PP r p p pc r p pcrpre p 

go 0 g g 0 0 g 

go 

0 

g ogooo g 0 

I- o~----~~~----~~------~r------4~------+-'-----+:----~ I 

C) Ol------~1-------1------~----~l------4------41----~ 

w 

~ 

z 

- 1.0 1-

z 

w 

1-

z 8 .8 

w 

0 

xo 

0 c:.GI2 

.4-

.2- p 

10 

r pp p per rr p pcpc r gpprcp r g prpp 

PP P per pp g 

I I I 

15 20 25 

0 

o o og o 

o o g go 

g 

g 

g 

I I 

30 35 

0 

0 0 g 

I 

40 

.4 

-

- .3 

Q 

_z 

.2 f-

-

.1 -

-

I 

45 10 15 

pp 

gg 

p pep p r 

p rp 

r p c r r cr p c p 

e g p r ppe 

I 

r p r r 

r P 

I 

20 25 

I I 

30 35 

0 

00 

0 0 

I 

40 

-

-

45 

TOTAL IRON, IN WEIGHT PERCENT 

FIGURE 18.-Total iron-variation diagram of olivine from Kalaupapa section. c, central part of an olivine grain in a cluster; g, groundmass 

olivine; o, fresh overgrowth on olivine phenocryst, in cluster, or in altered groundmass grain; p, central part of phenocryst; and r, rim 

of phenocryst but inside of alteration rim, if present. Italicized symbols indicate coincidence of two or more points. 

cally as groundmass olivine that plot in the field of 

phenocrysts in all probability are corners of olivine 

phenocrysts rather than groundmass olivine. For the 

purpose of subtracting phenocryst compositions from 

the whole-rock compositions, some olivine in clusters 

has been averaged with phenocryst compositions, especially where data on phenocrysts in a particular rock 

were scarce. 

The lack of a consistent chemical difference between 

the groundmass olivine and the fresh overgrowths indicates that they are coeval. 5 

With increasing (FeO' in the olivines, MnO content 

increases and NiO decreases (fig. 18). Apparently CaO 

5 ln the remainder of this report, the description of groundmass olivine composition also 

applies to the fresh overgrowth. 

increases with (FeO' also, but because of the scatter of 

the data, the trend is not so evident as for NiO and MnO. 

There seems to be no variation ofTi02 with (FeO' in the 

phenocrysts (fig. 18), even though there is little scatter 

in the data. 

Shaw and Jackson (1973) noted that 100Mg/Mg+ Fe 

for early-formed phenocrysts in Kilauean and Mauna 

Loan tholeiites determined by Wright (1971) are in fair 

agreement with those ofdunite xenoliths. They believed 

that the tholeiites are compositionally as well as spatially linked to the dunite xenoliths. However, Shaw 

and Jackson (1973) did not indicate whether minorelement concentrations in these two types of olivines 

are also similar. White (1966) reported earlier that 

olivine phenocrysts from Hawaiian alkalic lavas tend to 
MINERALOGY 23 

Z oT ppl I lg lppl I I I 

y g p g p 

~ _o-oo ______ ooo _________ _ 

v 0 0 0 U o o pr o o o rrp 

~ --g--....E_!__!B __ --go __ ...!£.C_[_!..._ __ _ 

R g g 

Q --~-.!._g ___ _ .2.__ ___ _!_...:.!_ ___ _ 

p g g 

0 og g o 

N rp M o p p i _o_~---~-- _£...----cioL_ ___ -7------ J g r c g rc I pr p p 

H 

G_____g___~LL.....Jl...._ __ ___i, _____ !_L ___ _ 

F p.c p c 

~----og--~_..E__P ___ ()g---c-u._ __ _ 

c g pp g p p B _____ ':.....£_ _______ _!____£_.E...._ __ _ 

A 1 I og o 

34 36 38 40 25 30 35 40 45 50 

s;o, MgO 

z p plgp I g I I I I P PI I 

2 y p c 

0 X ----~---+----------~-.2.-

t ~ 00 0 0 ~ U r p o o o prrp o o o ~ ~ _..J?_CL__Lgu ___ I- _ ____!.[.£_C....£!. ___ g __ _ 

~ R g g 

<( 

a: 

~ ~ __ __i!£___T---f---g_£__E..! ___ ___£_g __ 

<(0 go o g 

~ ~ p~ p rp 

~ i ----lr---o~~------,;-----~~-- j: J r g og cr g o <( I per p 

..J H ~ ~ - ----c/·e..._£!__ _______ 7{;-- .£...._ ____ _J. --

2 

;;; E ....£._....£._ _______ __p.....1!..... ________ _ 

w D c og c g o ~C PP g p p g :::;; B _P___£_ _____ __ ..£......_.£...._!........_ ______ _ 

<( 

(J) 

AL---w~o_o_~-~-L--L--PP-L-~~-~~-o-g~oo_~~-~~~ 

.2 .4 .6 .a 15 20 25 30 35 40 45 

CaO 'FeO' 

Q ~ p Pf g I 0 I I p p p lp g I g p 1 

~ ~ ---o'L._Q.__ ----2...8--- 1---2~-----

~~ rr goo 0 rp o 00 oo .?grropp i § ~g---- _g.££__go-- f-----""'()g__E_J'....£....11___!._ 

a.. R g g g 

<( 

a: 

~ ~ ..£!.1_......-2 __ _L_£.....! _ ___.£.. __ I--..£.....Y...!.._~-L_-

<( 0 r o g g rp g g o o ~ r p 

~ ~ pp 0 p p 0 op p 

: k ~h---- ----r}-J-0-z;---1---,?---/rp...L __ > J g o g ep go o g cr p j: J ppr pre c p r p 

~ ~ ~_L_ __ -!f!_ __ __L_l-__ _...i!-ff---

~- ECD ~---g--cr ....££."'Cgo ___ 1---go-~_p __ Gg PP g p g p l:J B _P _____ ___£_P___! ____ I--___ __!..j> __ ___l!_ 

~ ~ A p p ooo g I I p p I g ooo I I I oo g p I 

(J) 0 .1 .2 .2 .4 .6 .8 .1 .2 .3 .4 

Ti01 MnO NiO 

OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 19.-Weight percent of oxides in olivines from Kalaupapa 

section plotted against relative stratigraphic position. A-Z, samples 

from base of section upward. c, central part of an olivine grain in a 

cluster; g, groundmass olivine; o, fresh overgrowth on olivine 

phenocryst in cluster, or in altered groundmass grain; p, central 

part of pehnocryst; and r, rim of phenocryst but inside of alteration 

rim, if present. One MnO value of 1.10 for sample Z is not shown. 

be richer in CaO, (FeO,' Ti02, and MnO and poorer in 

MgO, Cr20 3, and NiO than the olivine from associated 

inclusions. He did not indicate whether any variation in 

CaO, MnO, or NiO other than that related to the (FeO' 

content of the olivine could be detected. Murata, Bastron, and Brannock (1965) showed that olivine phenocrysts and olivine of periodotite xenoliths from Hawaii 

increase regularly in MnO but irregularly in CaO content. They indicated that the CaO content may be partly 

a function oCFeO' content but that other factors are also 

involved. 

· As early as 1923, Vogt (1923) recognized that NiO 

content of olivine correlated negatively with (FeO' content. Forbes and Banno (1966) and Simkin and Smith 

(1970) examined the NiO content of olivine from various 

provinces. Simkin and Smith (1970) divided the olivines 

they studied into those from extrusive, hypabassal, and 

plutonic rocks and those from xenoliths. Their data 

show a marked decrease of NiO with increasing (FeO' 

and no separation of data for the four environments, and 

they concluded that there is no relation between NiO 

content and crystallization environment. Forbes and 

Banno (1966) also showed NiO content to correlate 

negatively with (FeO.' Their data show that NiO content of groundmass olivine contains slightly more NiO 

than phenocrysts and microphenocrysts of the same 

(FeO' content, which suggests that environment of crystallization may have some effect on the NiO content, 

although they did not discuss that possibility. 

Data shown in figure 18 indicate clearly that the 

environment of crystallization had a marked effect on 

the NiO content of the olivines in the Kalaupapa section. For a given (FeO' content, the groundmass olivine 

contains appreciably more NiO than the olivine phenocrysts. The most obvious difference in crystallization 

environment between groundmass olivine and olivine 

phenocrysts is pressure. Pressure apparently tends to 

inhibit the entrance ofNiO into the olivine lattice. It is 

unlikely that the higher NiO content of the groundmass 

olivine is due to increased concentration of NiO in the 

residual liquid, because NiO is depleted rather than 

enriched in the residual liquid during fractionation involving separation of olivine. A secondary effect of bulk 

composition of the host magma is suggested by the 

olivine in sample Z, the uppermost flow in the section, 

which compositionally is quite distinct from all the 

other lavas in the section (fig. 12). Two olivine phenocrysts and one groundmass olivine grain were analyzed 

in sample Z; they are the two most (FeO'-rich and NiOpoor phenocrysts and the most NiO-poor groundmass 

olivines shown in figure 18. The exceptionally low NiO 

values for the olivines in this rock are probably due to 
24 EAST MOLOKAI VOLCANIC SERIES 

the very low NiO content of the whole rock (0.006, which 

is rounded to 0.01 in table 1). 

It is not clear why the data of Simkin and Smith 

(1970) do not show any pressure effect, but variation 

resulting from pressure effects may have been masked 

by variations caused by compositional variations of the 

lavas that include the olivine. 

The NiO content of olivines in the Kalaupapa section 

is near the upper limit of values determined by both 

Forbes and Banno (1966) and Simkin and Smith (1970), 

and the NiO content of the whole rock is appreciably 

higher than those determined by Gunn (1971) for the 

tholeiitic lavas of Kilauea Iki and Makaopuhi. Forbes 

and Banno suggested that high NiO and MgO characterize ((primitive basalts" whether tholeiitic or alkalic, 

and on the basis of these criteria, the Kalaupapa lavas 

are indeed ((primitive" and have not been fractionated to 

any extent, especially not by separation of olivine, 

which is particularly efficient in reducing the NiO content in lavas. 

The MnO content correlates positively with (FeO' content of olivine (fig. 18), a conclusion also reached by 

Simkin and Smith (1970). There is appreciably more 

scatter in the MnO content of groundmass olivine than 

in olivine phenocrysts. From these data there is no reason to suspect pressure control of MnO content in the 

olivines. The MnO content of the phenocrysts and the 

one groundmass olivine in sample Z (the same sample as 

the one with exceptionally low NiO values) is far greater than that for olivine of similar (FeO' content from the 

other lavas. This may be the result of bulk composition 

of the host rock, as Simkin and Smith (1970) suggested 

for some of the samples in their study, but is not simply 

because the rock has a higher MnO content, as sample Z 

contains no more MnO than the other rocks in the section. Nor does it seem to be related to the degree of 

undersaturation of the lavas, as Simkin and Smith 

(1970) suggested, because sample Z is not appreciably 

more undersaturated than seven other rocks in the section that contain normative nepheline (when the CIPW 

norms are calculated from a dry-reduced basis). Sample 

Z, however, is set off from the other rocks in the section 

in that it contains considerably more Si02, P20 5, Na20, 

and K20 and less CaO and (for its MgO content) less 

Ti02. Hence, it appears to be more fractionated. 

The CaO content of the olivines shows only a weakly 

positive correlation with (FeO.' Simkin and Smith 

(1970) recorded a rather good separation of CaO between olivines from deep-seated plutonic rocks and ultramafic inclusions and those from hypabyssal and extrusive rocks. They suggested that because the CaO 

content is related to crystallization environment, it may 

be helpful in distinguishing olivine xenocrysts from 

olivine phenocrysts in lavas. Phenocrysts from the 

Kalaupapa lavas contain less CaO than the groundmass 

olivines (fig. 18) and thus tend to support the argument 

of Simkin and Smith (1970) for pressure control, but the 

large amount of scatter in the data shown here does not 

allow a conclusive statement. 

The Ti02 content shows no correlation with (FeO' (fig. 

18); the groundmass olivine, however, contains considerably more Ti02 than the olivine phenocrysts. The 

high Ti02 content of the groundmass olivine is not 

necessarily a result of pressure, as was suggested for the 

high NiO content, because the Ti02 content of the rest 

magma increases, up to a point, as crystallization proceeds, and a higher Ti02 content in the groundmass 

olivine (like that of the groundmass clinopyroxene) is 

expected. 

There is little or no overlap ofMgO, FeO, Si02, MnO, 

and Ti02 content of the unaltered olivine phenocrysts 

and unaltered groundmass olivine (fig. 19). The Si02 

and MgO content of both the phenocrysts and 

groundmass olivine decreases and the (FeO,' CaO, and 

MnO content increases upward in the section; the increase in MnO and CaO is more pronounced in the 

·groundmass olivine than in the olivine phenocrysts. 

The composition of the intratelluric alteration rims 

on the olivine grains was determined along with the 

fresh olivine (analyses given in table 4) and was found 

in almost all cases to contain more (FeO' than the core of 

the phenocrysts but less (FeO' than the fresh overgrowths. If there were no change in the Mg/Fe ratio 

during alteration of the olivine margins, then Mg/Fe 

decreases continuously from olivine phenocrysts to 

groundmass olivine. However, the compositions of 

alteration products in the interiors of some olivine 

phenocrysts indicate that the Mg/Fe ratio is reduced 

during alteration, suggesting that the gaps between 

phenocryst and groundmass olivine compositions 

shown in figure 19 may indeed be real. 

X-ray diffractograms have been made of two samples 

(A and E) having distinct intratelluric alteration rims 

but little or no deuteric alteration of the olivine cores. 

One of these samples (A) has fresh overgrowths; the 

other sample (E) has none. Magnetite, hematite, and 

pyroxene (enstatite) were identified from the diffractogram of sample E. The magnetite occurs in symplectic 

intergrowths with pyroxene at the extreme margins of 

the altered olivine grains and is similar to intergrowths 

described by Haggerty and Baker (1967). The phase 

dispersed throughout the alteration rim is presumed to 

be mostly hematite. Hematite could not definitely be 

identified from X-ray diffractogram of sample A, but 

optical comparison with sample E shows that minute 

grains of hematite (mostly less than 0.5 JL min diameter) 

are dispersed throughout the alteration rim. No magnetite pyroxene symplectites were observed in sample A. 

No ((iddingsite" (smectite-chlorite, Wilshire, 1958) or 

other minerals having a 1.4 nm (14 A) peak were iden-
MINERALOGY 25 

tified in either of these samples, although mica (illite?) 

may be present in sample A. There is only a few percent 

of water in the intratelluric alteration products if the 

iron is considered to be present as Fe20 3 (table 4), 

whereas more than 9 percent water is present in an 

average iddingsite (Wilshire, 1958). The available evidence therefore indicates that the intratelluric alteration product is dispersed hematite with some associated 

magnetite-pyroxene symplectite rather than ~~iddingsite" (smectite-chlorite). 

The alteration rims contain about the same minorelement content as the fresh olivine, with the exception 

of Al20 3 which is consistently higher in the altered 

rims.6 

COMPOSITIONAL VARIATION OF CLINOPYROXENE 

Clinopyroxene that occurs as phenocrysts (and microphenocrysts), in clusters with plagioclase and olivine, and in the groundmass has been analyzed with 

the electron microprobe. Table 5 gives analyses of 

clinopyroxenes in the Kalaupapa section. Figure 20 

shows the clinopyroxenes plotted on the pyroxene quadrilateral. Nearly all of them plot in the augite field; a 

few plot in the calcic augite (salite) field, and one plots in 

the subcalcic augite field (Brown, 1967). Fodor and 

Bunch (1972) showed that, for the island of Maui, 

tholeiitic basalts can be separated from alkalic and 

sThe possibility that the high AJ2o3 content of the altered olivine rims may be due to 

contamination by polishing compound (alumina) is not ruled out by the data presented here. 

A 10 20 

CaMg 

• • . -:' .. • • • 

• 

30 

D 10 20 E 10 

50 

.... • ,.,_ •• • 

• ••• •• • 

30 

En 

Calcic augite pcrrpgg Pf1P{:Prrrgege 

pcppreggg er e 

pr ~~gf' eee Augite 

g 

Subcalcic augite 

FIGURE 20.-Composition of clinopyroxenes in Kalaupapa section 

on pyroxene quadrilateral. p, central part of a phenocryst or microphenocryst; r, rim of a phenocryst or microphenocryst; c, central part of a clinopyroxene (augite) grain in a cluster; g, 

groundmass clinopyroxene; and e, rim (edge) of a clinopyroxene 

grain in a cluster. Italicized symbols indicate coincidence of two or 

~nore points. En, enstatite; Wo, wollastonite; Fs, ferrosilite. 

nephelinic basalts on the basis of CaO content of the 

clinopyroxenes; the range of wollastonite is 30-40 in 

tholeiites, 38-48 in alkalic basalts, and 47-51 in 

nephelinic basalts. All but one of the analyzed 

clinopyroxenes from the Kalaupapa section plot in the 

field of alkalic basalts on this scheme. A few plot in the 

tholeiitic field, which overlaps the alkalic field on the 

low-wollastonite side, and a few plot in the nephelinic 

field, which overlaps the alkalic field on the· highwollastonite side. 

Figure 21 shows the trends of the clinopyroxene comB 10 20 c 10 20 

• .. :.A.· • -t • ... .. .. • •• • • • 

20 F 10 20 G 10 20 

• • • ..... •• •• • 

·-=· 

,. . · • ... ,. • • 

FIGURE 21.-Compositional variation of clinopyroxenes in subsections of Kalaupapa section plotted on a ~ of pyroxene qu~drilateral: 

A, subsection A and BCD; B, subsection EF; C, subsection GHIJK; D, subsection LMNOP; E, subsection QRS; F, subsectiOn TUVW, 

G, subsection XYZ. 
26 

z 

y 

X 

zw 

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a: a Q p 

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CIJ 

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CIJ 

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D 

c 

B 

A 

z 

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A 

c g 

g e ee rpcc p 

g c g 

EAST MOLOKAI VOLCANIC SERIES 

g g g 

pee p gr e ggg 

e---p---g------g----

p e ccep r e g 

gg g 

.,---,---p-e--

gr P 

------~p--gg-----e 

r g 

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g g 

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g e c 

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46 

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g g 

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crgp r 

6 

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c g e p p c r g r p c c rrg p 

p cpc rgT --· ----cc------c------eec p e p c c g 

p c gp r r ----p--r-g------

p p P r g -----cc:--~--g----

g 

--~-c _____ g ------

p 

6 

r gpc 

8 10 

'FeO' 

pr,rp g e 

12 

c 

__ g ____ p __ g _____________ _ 

ep pgge 

ggg -----~-g----pgg ----g-p----c- r g p 

e r g p 

______ r eec~-----

g g 

g 

______ g __ g _________ _ 

g 

eg 

g 

rp 

c 

cr p 

r r pc g p c 

p 

_____ __!__!_£_r __ c _ ______L_ ___ _ 

e e e g ccc 

e e p c g cc p 

________ P_ crgp ___ _ 

g PP 

g p pc c 

g ________ gp r __ r ___ _ 

g r p 

e g pr 

______ g~__£L_ 

g g 

gg 

g r p 

g c 

grc p c p 

______ __J_r..ES__ 

e eg e C$ 

e e p pc 

g r pee 

p g p 

-----~pp P __ g p p cc 

r P P 

12 14 16 18 16 18· 20 

MgO CaO 

OXIDE CONTENT, IN WEIGHT PERCENT 

g Pr 

pg e 

--~~---­ gg 

gg 

gp 

ec g 

p p cr g 

c cg p 

____ __j).!.£.!LJL__ __ 

egc e e 

.2 

c ee p rc g 

WPP ________ _ 

gccp 

g 

.4 

Na.2 0 

.6 

14 

g 

FIGURE 22.-Weight percent of oxides of clinopyroxene from Kalaupapa section plotted against relative stratigraphic position. A-Z, 

samples from base of section upward. p, central part of a phenocryst or microphenocryst; r, rim of a phenocryst or microphenocryst; 

c, central part of a clinopyroxene grain in a cluster; e, rim (edge) of clinopyroxene grain in a cluster; and g, groundmass clinopyroxene. Dashed horizontal lines delimit subsections. Italicized symbols indicate coincidence of two or more points. 
MINERALOGY 27 

positions in individual subsections (except fig. 21A in 

which subsection A and BCD are combined). The trend 

in figure 21A is toward subcalcic augite, and one of the 

clinopyroxenes plots in the field of subcalcic augites. 

The clinopyroxenes in subsection EF (fig. 21B) are split; 

these from sample E (the lowermost flow of the subsection) trend toward subcalcic augite, and those from 

sample F trend toward ferroaugite. The clinopyroxenes 

in the remainder of the subsections show trends toward 

ferroaugite, with the exception of those in subsection 

QRS which show no clear trend because there are no 

clinopyroxene phenocrysts in these flows. 

Poldervaart and Hess (1951), Wilkinson (1956), Muir 

and Tilley (1964), and Brown (1967), among others, 

showed that clinopyroxenes in saturated (tholeiitic) 

basalts trend toward subcalcic augite. Other workers 

(Wilkinson, 1956; LeMaitre, 1962; Brown and Vincent, 

1963; Barberi and others, 1971) showed that 

clinopyroxenes in alkalic lavas trend toward ferroaugite. 

On the basis of clinopyroxene trends in the subsections, one can argue that lavas in the lower part of the 

Kalaupapa section, if not tholeiitic, certainly must be 

transitional to tholeiitic basalt. The absence of modal 

hypersthene or pigeonite and the presence of olivine in 

the groundmass lead me to consider them transitional 

between tholeiitic and alkalic rather than tholeiitic. 

Smith and Lindsley (1971) determined that a trend 

l g I I I 

toward subcalcic augite was produced metastably as a 

((quench trend" in chilled margins of a Picture Gorge 

Basalt from Oregon, while the trend for clinopyroxenes 

from the center part of the flow parallels that in the 

alkalic Skaregaard intrusion. It is unlikely that the 

trend toward subcalcic augite developed in subsections 

A and BCD is the result of quenching, because the 

samples analyzed are nearly holocrystalline like most of 

the other samples in the section. 

Figure 22 shows clinopyroxene compositions plotted . 

against relative stratigraphic position. The increase in 

Na20, Ti02, and Al20 3 (and a decrease in MgO content) 

upward in the section is apparent. The margins of the 

clinopyroxene phenocrysts, clinopyroxenes in clusters, 

and groundmass clinopyroxenes are enriched in (FeO,' 

Na20, Ti02, and MnO and depleted in MgO, CaO, and 

Cr20 3 relative to the cores of clinopyroxene phenocrysts 

and clinopyroxenes in clusters. 

COMPOSITIONAL VARIATION OF PLAGIOCLASE 

Plagioclase feldspars that occur as phenocrysts or 

microphenocrysts, in clusters with olivine and 

clinopyroxene, and as laths in the groundmass were 

analyzed with the electron microprobe. Interstitial 

groundmass feldspars were not analyzed. Table 6 gives 

analyses of plagioclase minerals in the Kalaupapa section. 

Figure 23 is an An, Ab, Or diagram plotted from the 

I g I e g l I I z 

y p g r ge e g repgp e e rg e P ep 

X 

z Q'(j 

!:: u 

~ T Q.. s ~ R I 

Q.. 

<( 

~ Q 

j: p 

<( 0 a: N 

~ M 

w L 

> K 1- J 

~ I 

w H a: G 

Z F 

~ E 

~ D Q.. c 

~ 8 en 

A 

- g 

gp r 

r ge 

eeg re e 

g g 

g 

g 

p e p r r e pe.p e r r g 

p e r r ee cg 

c p ece p 

p gc r 

p eg r r 

pp r 

pg pp 

c g p 

g 

cpr r g 

c gpr r 

2 

g 

e e p 

g 

g 

r g 

e g 

g 

eel! 

g 

3 

g gg gg 

p g g gg 

p gr g 

p r g e c r p 

r pee ee g ge r e c 

gg g 

g g g g 

g g gg 

g pr prg 

ge g e p c g r r rgr c p 

per e g r p pr rg e e p 

epc 8.. r ' e g .L- e ee g e.e e ee eg c c 

peep e e e e c p c p 

r pee g g e e pr 

p e 1! r r & srr (! c (!,_ 

gpr r g p 

P PP r g rg p p p p p 

ep p g g ppcc 

g g 

pg rg r g pe p p 

l 

p g c rr I l l 

rp e [ gl p 

4 .2 .3 .4 0 .2 .6 

MnO 

OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 22.-Continued. 
28 EAST MOLOKAI VOLCANIC SERIES 

An 

FIGURE 23.-Ab, Or, An diagram of plagioclase from Kalaupapa 

section. p, central part of phenocryst or microphenocryst; r, rim of 

phenocryst or microphenocryst; c, central part of plagioclase grain 

in a cluster; e, rim (edge) of a plagioclase grain in a cluster; and g, 

groundmass plagioclase lath. Italicized symbols indicate coincidence of two or more points. 

plagioclase analyses. Most of the plagioclase grains that 

occur as phenocrysts and microphenocrysts, or in clusters, range in composition from An80, Ab20, Or0 to An 58, 

Ab4o, Or2, although two microphenocrysts (both from 

sample Z, a mugearite) are as low as An49, Ab48, Or3. 

One grain in sample X that was first classified as a 

microphenocryst contains An34, Ab61 , Or5, but reexamination shows that it may be a groundmass lath. 

Groundmass laths range in composition from An61.5, 

Ab36.5' Or2 to An39, Ab57, Or4, overlapping the composition of phenocrysts, microphenocrysts, and plagioclase 

of clusters. The lowest An and highest Or and Ab 

groundmass plagioclase (fig. 23) is from sample Z and is 

not included with the basalt ranges. 

In the entire Kalaupapa section, the compositions of 

phenocryst and groundmass plagioclase overlap considerably, but in single samples, the compositions, with a 

few exceptions, do not overlap. Despite the scatter of 

data points in figure 24, the Na20 content increases and 

the CaO content decreases upward in the section. 

Salllple Z is very close to the composition of the average mugearite given by Macdonald and Abbott (1970) 

and, by definition, should contain oligoclase, but it con-. 

tains andesine instead. A similar discrepancy was noted 

by Keil_, Fodor, and Bunch (1972) in the lavas of West 

Maui and Haleakala volcanoes. 

The groundmass, rim, and edge plagioclase compositions emphasize the more fractionated character of the 

lavas in the upper parts of the subsections. Na20, K20, 

and BaO increase and CaO and Al20 3 decrease upward 

in the subsections (fig. 24). 

COMPOSITIONAL VARIATION OF OPAQUE MINERALS 

A wide variety of oxide phases showing extensive 

solid solution among the various end members is present in the lavas of the Kalaupapa section (table 7). Some 

chromite grains that occur as microphenocrysts in the 

groundmass as well as inclusions in olivine contain 

more than 50 percent Cr20 3. Many of those not entirely 

enclosed in olivine phenocrysts are continuously zoned 

from a core of chromi te to margins of ul vospinel (usually 

on the titaniferous magnetite side of stoichiometric 

ulvospinel). Brown (1967) indicated that Hthere is no 

evidence from the large fractionated intrusions, particularly the Bush veld, of a continuous series of spinels 

from chromites to titaniferous magnetites." However, 

continuous solid solution between chromite and ulvospinel has been reported in the tholeiitic lavas of Kilauea Iki and Makaopuhi, Hawaii (Evans and Wright, 

1972), from the lunar rocks by several investigators 

(Agrell and others, 1970; Haggerty, 1972; and others), 

as well as that reported here. 

The inicrophenocrysts range in diameter mostly from 

100 to 250 p.m, but a few are larger than 250 p.m. The 

groundmass minerals are ilmenite, ul vospinel to 

titaniferous magnetite, and (rarely) rutile. The opaque 

minerals in the groundmass, though generally smaller 

than the microphenocrysts, are in places as large as 

some of the smaller microphenocrysts, and opaque minerals tend to cluster so that clots of tiny octahedra or 

other crystal forms are easily mistaken for microphenocrysts. Hence some that were assumed to be 

microphenocrysts on the basis of their size turned out to 

be groundmass in their composition. Some of the points 

plotted as microphenocrysts in figures 25 and 26 should 

more reasonably be plotted as groundmass grains. 

The groundmass opaque minerals are usually unmixed, as a lattice network of ilmenite lamellae in 

titaniferous magnetite, as titaniferous magnetite with 

patches of ilmenite (usually toward the edge of the 

grain), or as half ilmenite and half titaniferous magnetite sandwiched between two ilmenite patches. Several 

tiny Ti02-rich areas (approaching rutile) were observed, one of which is included in table 7 and figures 25 

and 26. 

The exsolved phases usually have gradational contacts with the host. In order to obtain analyses that total 

roughly to 100 percent, at least two areas were selected 

in each grain, one giving a maxium Ti02 and the other 

giving a minimum Ti02 content. This procedure biases 

the analyses toward Ti02-rich and Ti02-poor end members, but in spite of this bias, the solid solution shown 

between ilmenite and titaniferous magnetite and between ul vospinel and chromite is complete and must be 

real. In fact, complete solid solution was detected in a 

single grain containing more than 30 percent Cr20 3 and 

less than 4 percent Ti02 in the chromite core and more 
MINERALOGY 

z I lpp g I I PP I I I I p I g 

z y 

0 X 

1- w 

(/) v 

0 u c... T 

pg pg g 

pg r p r r g p pg _.E_ 

pp r g r g rp r p pp r r g 

pp rpr r g g r r r ppp P PP rr r g 

p p p r r g g r p p p p p p r r g 

p p r g gr p p p 12 r g ·- u s I R 

g p gp g p g p p g 

c... 

<( 

a: 

(.9 Q p pc g r r g p p p cp g r ·- 1- p p p rr g g g r p p p p rr g <( 0 a: N 1- M (/) 

r p e g g e r p p c pp r e g 

p g g p p g 

p g g p p g 

w L p pg r r g p p pp g r 

> K 

f= J <( I ...J H w G a: 

c p g e r eg p c c p g e p p g g rp p p pr g 

pp p rg g r p r pp pp p rgr 

p c rp e g ge p c r p p c p eg -

z F prp g g r rp e p pc e rr g 

(/) E 

w D ...J c a. 

~ B 

p g g p p g 

pc r ge e g c r g e ·- cpr 

p g g p p g c eg e g r c cp eg 

<( 

(/) 

A p cr g g cpr p p p cr g I I I I I 

50 55 60 65 26 3 6 7 Si0 2 

z I pp I I I I I I I I I I 

g g p 

y pg g 

X p g p p r gp 

w p r r g r g r p 

v p r r r g g r r r p p 

u p pp r g g r r p p p 

z T p g gr p p 

0 s pg p g 

~ R p g g p 

(/) 

0 

c... 

u 

I Q c... ppgr r g pc p <( p a: pp r g r g r p p 

(.9 0 p r g g r e ppc 

1-

<( N pg g p 

a: 

1- M p g g p (/) 

w L pg r r g p 

> K c p g e e g p c 

1-

<( p p r g g pr p 

...J ppr g rg p r p w 

a: H 

z G p e g g p c r p 

(/) F c r g g r p r ec p w 

...J 

c... 

~ E pg g p <( 

(/) D p c g e e g r c p 

c p g g p 

B pc g r g g 

A c p g g cp p 

I I I I I 

0 2 3 4 8 12 16 CaO OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 24.-Weight percent of oxides in plagioclase from Kalaupapa section plotted against relative stratigraphic 

positions. A-Z, samples from base of section upward. p, central part of phenocryst or microphenocryst; r, rim of 

phenocryst or microphenocryst; c, central part of a plagioclase grain in a cluster; e, rim (edge) of a plagioclase grain 

in a cluster; and g, groundmass plagioclase lath. Italicized symbols indicate coincidence of two or more points. 

Figure continued on following page. -

29 
30 EAST MOLOKAI VOLCANIC SERIES 

than 22 percent Ti02 and less than 3 percent Cr20 3 in 

the ul vospinel rim. 

Major elements in the chromite show marked varia:.. 

tion with Cr20 3 content (fig. 25). Al20 3 and MgO decrease almost to zero as Cr20 3 decreases to zero, and 

Ti02 and (FeO' increase as Cr20 3 decreases, becoming 

more scattered near zero Cr20 3 content. At zero Cr20 3, 

(FeO' and Ti02 range from values expected for titaniferous magnetite almost to rutile (fig. 25). Because it is not 

possible to separate Fe3+ from Fe2+. with the electron 

microprobe, no evaluation of mineral variations on the 

FeO-Ti02-Fe203 diagram has been attempted. The total 

iron could be partitioned between FeO and Fe20 3 if it is 

assumed that there are no defect structures present, but 

such an exercise is beyond the scope of this paper. 

SUMMARY 

To unravel the detailed compositional variation of a 

volcanic sequence, closely spaced sampling and firm 

stratigraphic control are necessary. This type of sampling of the Kalaupapa section revealed that the fractionation trend is discontinuous; it proceeds with several steps forward toward more fractionated compositions and then reverts abruptly to a less fractionated 

z 

Q 

!:: 

en 

0 

a. 

~ 

I 

a. 

<{ 

a: 

(.9 

f: 

<{ 

a: 

1-

en 

w 

> 

f: 

<{ 

..J 

w 

a: 

~ 

en 

w 

z 

y 

X 

w 

v 

u 

T 

s 

R 

Q 

p 

0 

N 

M 

L 

K 

J 

I 

H 

G 

F 

..J E a. 

~ D 

~ c 

8 

A 

I 

g 

r 

r g r 

r p 

p g 

g 

p 

p r 

p 

p 

p r 

c 

r 

g r 

g 

g e 

p 

g 

g 

e g 

g 

I 

0 

p I g I I I 

p 

g 0 p 

p g 

p p r 

p g 

g 

g 

g 

g 

g 

g p 

g p 

g e 

g 

e 

I I I. I I I 

.02 .04 .06 .08 .1 0 .12 

BaO 

composition. The Kalaupapa section can be divided into 

eight subsections on the basis of the discontinuous fractionation trend. These subsections are the same as the 

ones that would result from dividing the section on the 

basis of phenocryst content of the lavas. The upper subsections are generally more fractionated than the lower 

ones. 

Petrologically the lavas in the lower part of the section are alkalic, but chemically they are tholeiitic and 

are best classified as transitional between tholeiitic and 

alkalic basalt. The lavas in the upper part of the section 

are, by any classification, alkalic. 

The subsections are believed to have resulted from 

distinct magmatic batches that are generated in the 

mantle on a periodic rather than a continuous basis. 

Similar batches were first proposed by Powers (1955) to 

explain chemical variation of tholeiites and eruptive 

histories of Hawaiian volcanoes and were later used by 

Wright and Fiske (1971) to explain the compositional 

differences between historic and prehistoric lavas of 

Kilauea. 

Subtraction of the phenocryst content from the dryreduced whole-rock compositions removes compositional variation that results largely from shallow fracI p p g I 

pg 

pr g 

p r g ·- r rp p g r 

pr g p 

p p r g 

p g 

p g 

... 

PP gr 

r g p 

rpgp e 

p g 

p g 

p r g 

e P c g 

p rp g 

p pp r g 

(!C ~ r g e 

cp p e g r 

g p 

p c e gr 

p g 

p c g re 

p c r p g 

I I I I I I 

.14 .4 .6 1.0 1.2 

OXIDE CONTENT, IN WEIGHT PERCENT 

FIGURE 24.-Continued. 
SUMMARY 31 

tional crystallization and allows identification of a 

deeper (more fundamentaDfractionation trend mostly 

1-

z 

w 

u 

a: 

w 

Q. 

II 

CJ 

w 

~ 

~ 

1-. 

z 

w 

"' 0 

"' 0 

i= 

1-0 

z Ol 

s~ 

w 

0 

X 

0 

0 

Q) 

20- I 

pp 

p f r r ppr r r p i 

Q f;;rPPP 

80-

60-r 

g 

g 

g-nmenite 

40 ~ r 

g r 

g r 

I 

~UI:ospinel r g 

g 

g 

g r p rpp 

20 1 ~r rr . 

p r r p l 

g p p 

p p pr p 

pg p p 

g p 

I 

PP PP 

p 

p p 

I 

PP PPP 

I 

p p p p 

i p p p i 

i p p 

I 

I 

p p 

I I 

g P ippp p "Chromite" 

Q Mag~etite 1 pip p r p p 

I 

20 ~ 

i g rpprrrpp prpp 

Q !'~PPP 1 

g 

p 

80- p p g p 

~ p g p 

:-........ Ulvospinel 

g r 

r grpp 

I 

p 

.P p I p 

p p 

P I 

I 

60 g ~; p p p 

IT rp p p p 

r P P g p 

;_..,.nmenite r 

gr 

g 

g 

ri 

i p p 

i pp p p p p 

I 

I 

i p 

i 

I 

I 

"Chromite" 

p p 

I 

I 

-

-

-

-

-

-

-

~ 40 g i p i p p 

p 

g 

g 

r 

20 -

p 

p p p "Chromite" 

p p 

-

o~----~~----~~----L-----L-----~--~ 

10 30 50 

Cr2 0 3 

OXIDE CONTENT, IN WEIGHT PERCENT 

controlled by aluminous clinopyroxene. The subsections 

defined by the whole-rock compositions are also seen in 

the phenocryst-free compositions. Therefore the subsections are not the result of shallow fractional crystallization alone. The trends of the phenocryst-free compositions could be produced either by deep 45-75 km, 

28-46.5 mi) fractional crystallization of an aluminous 

clinopyroxene or from partial melting of a garnet pyroxenite leaving a residuum of aluminous clinopyroxenite. Although addition or removal of aluminous clinopyroxene can account for most of the trends in these transitional and alkalic lavas, desilication of tholeiitic 

magma to produce an alkalic one cannot, because the 

silica content of the aluminous clinopyroxene is very 

close to that of the lavas. 

The most fayalitic olivine phenocryst contains less 

iron than the least fayalitic groundmass olivine. NiO 

content of the groundmass olivine and the olivine 

phenocrysts decreases with increasing (FeO' content 

along separate but parallel trends (fig. 18). Extrapolation of these trends to a common (FeO' content shows the 

groundmass olivine to contain more NiO than the 

olivine phenocrysts. It is possible that these differences 

in NiO content result from crystallization of the phenocrysts at higher pressures than the groundmass olivine. 

Clinopyroxene compositions near the base of the section (in the two lowest subsections) trend toward subcalcic augite, as is typical of tholeiitic lavas (fig. 22). 

This is supporting evidence that the lower part of the 

section, if not tholeiite, is transitional between tholeiitic and alkalic basalt. Clinopyroxene compositions in 

the upper part of the section trend toward ferroaugite, 

as is typical of alkalic lavas. The composition of 

clinopyroxenes in these lavas provides as reliable a distinction between tholeiitic and alkalic lavas as wholerock compositions. 

Plagioclase increases in N a 20 and K20 and decreases 

in CaO and Al 20 3 upward in the section. K20 also increases in the groundmass plagioclase in the upper 

flows of the subsections (fig. 24). 

Chromite crystallized simultaneously with olivine 

and is present in the groundmass and as inclusions in 

olivine phenocrysts. Solid solution between chromite 

and ulvospinel is continuous (figs. 25, 26). The other 

groundmass oxide minerals range from titaniferous 

magnetite through ulvospinel to rutile and commonly 

show a variety of unmixing textures. 

FIGURE 25.-Variation of Cr2 0 3 in opaque minerals from 

Kalaupapa section plotted relative to Al2 0 3 , Ti02 , MgO, and 

'FeO.' p, microphenocryst; r, rim of phenocryst; e, edge of 

groundmass grain; i, inclusion in olivine; and g, groundmass 

grain. Italicized symbols indicate coincidence of two or more 

points. 
32 

'0 

:g 

EAST MOLOKAI VOLCANIC SERIES 

'0 '0 '0'0 

FeAI 2 0 4 

FeAI 2 0 4 .6 .8 Fe2 Ti04 

4-- --~--------.--------.--------.-----~~1.0 

p 

fgg 

rg g 

ppgg 

pprgpg 

ip r pprg p pp ppr g 

ir g 

g 

P i e --------P----r-- .8 

P P ri 

p p 

p p 

p p p 

p 

p 

p ------j--------- .6 

p 

FeCr 2 0 4 •

6 .

8 Fe2 Ti04 

+-- ---.---------.---------.--------.------g 1 .0 

p g 

rg 

pprg 

p p ppr rp 

rp ppprg 

p ppp p r p g 

i r g 

p g 

p i e ------P------r-- .8 

p p 

Fe2 Ti04 p 

pp 

p 

p 

p 

p 

p 

P r 

p 

----i----------- .6 

p 

FIGURE 26.-Compositional variation of opaque minerals from Kalaupapa section on FeAb04- Fe2Ti04- FeCr20 4-

MgA~04 - M& Ti04 - MgCr20 4 trigonal prism. Points plotting away from Fe2 Ti04 - Mg2 Ti04 edge represent 

those with increasing chromite content. p, microphenocryst; r, rim of phenocryst; e, edge ofgroundmass grain; 

i, inclusion in olivine; and g, groundmass grain. Italicized symbols indicate coincidence of two or more points. 
REFERENCES 33 

REFERENCES 

Agrell, S. 0., Peckett, Andrew, Boyd, F. R., Haggerty, S. E., Bunch, T. 

E., Cameron, E. N., Dence, M. R., Douglass, J. A. V., Plant, A. G., 

Traill, R. J., James, 0. B., Keil, Klaus, and Prinz, Martin, 1970, 

Titanian chromite, aluminian chromite, and chromium ulvospinel from Apollo 11 rocks, in Apollo 11 Lunar Sci. Conf. Proc.: 

Geochim. et Cosmochim. Acta v. 34, supp. 1, p. 81-86. 

Anderson, A. T., and Wright, T. L., 1972, Phenocrysts and glass 

inclusions and their bearing on oxidation and mixing of basaltic 

magmas, Kilauea Volcano, Hawaii: Am. Mineralogist, v. 57, p. 

188--216. 

Barberi, Francesco, Bizouard, Henri, and Varet, Jacques, 1971, Nature of the clinopyroxene and iron enrichment in alkalic and 

transitional basaltic magmas: Contr. Mineralogy and Petrology, 

v. 33, p. 93--107. 

Beaman, D. R., and Isasi,J. A., 1970, A critical examination of computer programs used in quantitative electron microprobe analysis: 

Anal. Chemjstry, v. 42, p. 1540-1568. 

Beeson, M. H., 1967, A computer program for processing electron 

microprobe data: U.S. Geol. Survey open-file report, 40 p. 

Beeson, M. H., and Jackson, E. D., 1970, Origin of the garnet pyroxenite xenoliths at Salt Lake Crater, Oahu: Mineralog. Soc. 

America Spec. Paper, v. 3, p. 95-112. 

Benson, W. N., and Turner, F. J., 1940, Mugearites in the Dunedin 

district: Royal Soc. New Zealand Trans., v. 70, p. 188--199. 

Betz, Fredrick, Jr., and Hess, H. H., 1942, Thefloorofthe North Pacific 

Ocean: Geog. Rev., v. 32, p. 99--116. 

Binns, R. A., 1969, High-pressure megacrysts in basanitic lavas near 

Armidale, New South Wales: Am. Jour. Sci., v. 267-A, p. 33--49. 

Binns, R. A., Duggan, M. B., and Wilkinson, J. G. F., 1970, High 

pressure megacrysts in alkaline lavas from northeastern New 

South Wales: Am. Jour. Sci. v. 269, p. 132-168. 

Brown, G. M., 1967, Mineralogy of basaltic rocks, in Hess, H. H., and 

Poldervaart, Arie, eds., Basalts; the Poldervaart treatise on rocks 

of basaltic composition: New York, Interscience, p. 103--162. 

Brown, G. M., and Vincent, E. A., 1963, Pyroxenes from the late stages 

of fractionation of the Skaergaard intrusion, East Greenland: 

Jour. Petrology, v. 4, p. 175-197. 

Chayes, F., 1971, Ratio correlation; A manual for students of petrology and geochemistry: Chicago, Univ. Chicago Press, 99 p. 

Cox, Allan, 1969, Geomagnetic reversals: Science, v. 163, p. 237-244. 

Daly, R. A., Manger, G. E., and Clark, S. P., Jr., 1966, Density of rocks, 

in Clarke, S. P., Jr., ed., Handbook of physical constants: Geol. 

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Dalrymple, G. B., Silver, E. A., and Jackson, E. D.,1973, Origin ofthe 

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34 EAST MOLOKAI VOLCANIC SERIES 

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Petrology, v. 3, p. 342-532. 
TABLES 1-7 
TABLE 1.-Chemical analyses of whole rocks from the Kalaupapa section 

[Localities A-Z are shown in fig. 3. Dry-reduced compositions are plotted to facilitate comparison with microprobe analyses of minerals for which FeO and Fe2 0 3 cannot be separated. They were determined by recalculating total 

iron as FeO, subtracting R,O and C02 , then normalizing to 100 percent. Analysts: V. C. Smith, except Cr2 0 3 and NiO by R. L. Rahill] 

KLPA•l KLPA-2 KLPA-3 KLPA-4 KLPA-SA KLPA-7A KLPA-8B KLPA-9A KLPA-11 KLPA-14A KLPA-15A KLPA-16A KLPA-16B 

A B c D E F G H I J K L M 

Chemical analyses (weight percent) 

5102 47o38 45,14 46,92 49.04 45.61. 46.48 45.99 45.36 45.77 46.47 4e,4e 46.05 45o42 

AL203 l3o50 13.28 14.24 14,33 11.32 15.57 13.14 13.07 14.87 14.31 15,42 12.12 12o53 

fE203 .3ol8 5,65 4,09 5,94 4,4Q 4,25 4o59 6,64 4o56 lo21 2.32 2,58 7o04 

no 9o74 7,67 8,64 7,14 7,57 8,64 7o84 6.30 9ol3 10.08 10.08 10.36 6o57 

MGO 9o24 12,42 9ol8 5,66 16,98 7,19 12.87 13,07 7o45 8,33 5,09 12,34 llo43 

CAU 9o92 10,14 9.92 10,2o 9,44 9,75 9o90 9,63 9o59 lO,oo 10.12 10.06 9o60 

NA20 2·~8 1,94 2ol0 2,59 1.47 3,02 2.02 lo96 2.48 2.68 3.16 2.30 2o26 

1<20 Oo54 0,19 0,17 0,64 0.14 0,68 0,26 0,23 Oo40 Oe43 0,79 0,69 Oob8 

H20 Oo21 0,36 Oo83 0,34 0,26 0,41 Oo42 o.sa 1o20 Oo37 Oo50 

TI02 2o81 2,61 2o55 3.20 1.87 3,00 2,09 2.08 3o25 3,06 3,38 2.68 2o70 

P205 Oo40 0,26 Oo32 0.41 0.21 0,42 Oo26 0.26 Oo44 Oo42 Oo51 o.35 Oo40 

MNO Ool9 0,18 Ool9 0,19 Ool8 0,18 Oo17 Oo18 Oo20 Ool9 Oo19 0,19 Oo20 

C02 Oo02 0,01 o.o1 0,01 o,o1 0. 01 0,01 o.o1 0.01 

s 

CH203 Oo04 0,10 0,06 0,03 0,13 0,03 0.11 0.12 0.07 0,04 0,03 0,09 Oe10 

NlO Oo03 0,05 0.04 o.o2 o.1o 0,03 Oo07 0.01 0,03 Oo03 Oo01 o.o5 o.os TOTAL 99, ·ra 100o00 99.26 99,79 99,83 99.66 99o74 99,56 99.44 99,62 Q9,59 99.87 99o4H 

CIPW Norms 

Q Oo023 5o667 

OR 3o19B 1,123 lo012 3,790 0.829 4.032 lo540 lo365 2.377 2o551 4.688 4.083 4o031J 

AB 2letH9 16,416 17o902 21.962 12.460 25.642 17.137 16.658 21.103 22.764 26.849 19.487 19o223 

AN 23o712 26,966 29.142 25.638 23,916 27.012 26.086 26.301 28.420 25,A44 25.662 20.735 22ol51 

NE 

WO 9o546 9.009 7o628 9.472 9.001 1 .au 8.931 8.315 6.903 8,852 8.911 u.ns 9o644 

EN 14.177 18,642 23.033 14.126 21.3B4 8.905 17 o352 22.151 16.914 11.422 10.111 8.049 19o628 

FS 6o770 3,280 lh712 3.289 3.793 3e860 4o059 2.043 7o289 6ol53 9,059 3.360 lo492 

FO 6o227 8,612 14.700 6,351 10.360 7.389 lo223 6.589 1.834 15.924 6o2"lB 

fA 3o278 1.670 2.874 3.034 2o67l 0.751 Oe581 3.912 1e811 7.327 Oe528 

MT 4o621 8,192 5,974 8,631 6,521 6o183 6.672 9.670 6e649 4.672 3.378 3.746 l0o261 c~ Oe059 0.147 Oo089 0.044 0 ol92 0,044 Oe162 Oo178 o.lo4 0,059 o.o44 0.133 Oo148 

HM 

IL 5o349 4.957 4o879 6,090 3,Sc;8 5.717 3.980 3.968 6e207 5.834 6e446 5.097 5o155 

AP Oo950 0.616 Oo764 0.973 Oo498 0,998 Oo617 Oo619 1o048 Oe999 1.213 0.830 Oe952 

PR 

cc Oo046 0.023 Oo023 Oo023 0.023 Oo023 Oo023 Oo023 Oo023 

TOTAL 99.811 99o654 99.181 99.682 99,749 99,611 99.592 99.430 98,817 99,651 l00o028 100.018 99.519 

SALIC 48.790 44o505 48,079 57,057 37,205 56.685 44.764 41to324 51.900 51.159 57.199 44.305 45.414 

fEMIC 51.022 5c;.l49 51.102 42.625 62.544 42,926 54,828 55.106 46,917 48,493 42.829 ss. 713 54.104 

DI 18.488 17,084 14.683 18.045 17.071 15.087 17.016 15.650 13o332 17.201 17.592 21.,62 Hhl21 

DIWO 9o546 9,009 7.628 9,tt72 9o01'11 1 .au 8.931 8.315 6.903 8,852 8o91l 11.225 9o644 

OlEN 6o051 6,867 5ol19 6,954 be854 !:1.07& 6eS52 6,715 4e493 5.426 4,579 7,363 7o879 

DIFS 2e890 1,208 le936 1e6l9 1.216 2o200 1o533 0,619 1,936 2.923 4o102 3.074 Ot599 

HY 12.005 13,848 24.691 8,842 17.107 5,488 13.326 16,859 17.774 9,226 10.488 0,973 12.642 

HYEN 8o125 11.775 17,915 7.172 14,530 3,829 10.800 15.436 12,421 5.996 5,532 0.686 lle749 

HYFS J.8ao 2.072 6o776 1.670 2.57ts 1.660 2o526 1.424 5.353 3.230 4o956 Oe2A6 0.893 

OL 9o505 10,283 11.574 9,385 13.031 8.140 1.803 10.502 3o645 23,251 6o826 

OLFO 6o227 8,612 14.700 6,351 10.360 7.389 le223 6.589 lo834 15.924 6o298 

OLFA 3te?78 1,670 2.874 3,034 2o67l Oo751 o.se1 3,912 le8ll 7.327 Oe528 

C/.:) 

0':1 

tt:! 

~ 

r::n 

t-3 

~ 

0 

t""' 

0 

~ 

~ 

-

< 0 

t""' 

0 

~ 

z 

0 

r::n 

tt:! 

l=d 

t;3 

r::n 
KLPA-17A KLPA-19B 

N 0 

Sl02 45,54 47.34 

AL203 12,50 15,72 

FE203 6, 71 7.90 

FEO 6,79 5.49 

MGO 11,29 4o00 

CAO 9,65 8o34 

NA20 2,31 3o54 

K20 0,68 1o20 

ti20 0,10 Oo33 

Tl02 2,72 3o78 

P205 0,36 0,67 

MNO 0,19 Oo20 

C02 Oo01 

s 

CR203 0,10 OoOJ 

NIO 0,05 o.o1 

TOTAL 98o99 98o56 

~ 3ol9A 

OR 4,059 7o195 

Ats 19,746 30.392 

AN 21,952 23.802 

NE 

wo 10,035 5o709 

EN 18,608 10.108 

FS 1,845 

FO 6,865 

FA 0,750 

fliT 9,828 7.484 

CM 0,149 Oo04!) 

HM 2.853 

IL 5,219 7.284 

AP 0,861 lo6l0 PA 

cc 0,023 

TOTAL 9q,918 99e702 

SALIC 45.757 64,586 

FEMIC 54.161 35.116 

DI 18,900 10o642 

DIWO 10.035 5.709 

OlEN 8,065 4o934 

OIFS 0,800 

HY 11.589 So174 

HYEN 10,544 5ol74 

HYFS 1,046 

OL 7,615 

OLFO 6,865 

OLFA 0,750 

TABLE 1.-Chemical analyses of whole rocks from the Kalaupapa section-Continued 

KLPA-19D KLPA-20A KLPA-23B KLPA-25A KLPA-27 KLPA-28 KLPA-29 KLPA-39 

p Q R s T u v w 

Chemical analyses (weight percent) 

47,98 45.77 47.18 46.69 45,52 45,64 48,15 47,76 

15,41 15,50 15.20 15.65 13.95 14.04 l7o20 17.88 

4,57 7,81) 5,36 4,85 8,48 4o09 4e52 7ol3 

8,29 5,85 7.83 8.59 5.37 10.16 7o20 4o69 

4,31 6.46 5.90 5o91 8o9l Boll 3.78 3o53 

8,81 9o11) 9,56 8o67 10,01 9o17 9o36 8.93 

3,62 3,00 3,05 2o88 2o16 2o96 3o66 3.49 

1,20 OoAA o.es 0,89 0.45 0,98 1o12 lo06 

0,16 Oo4A Oo29 Oo8l 0.84 Ool6 o.zo o.5a 

3,76 3,56 3,39 3o39 2o76 3o30 3,40 3o29 

0,68 0,51 Oo48 0,48 0,36 0,59 0.62 0.59 

0.20 O,lA 0.19 Oel9 0.20 o.zo Ool9 Oo19 

OoOl 

o,ot 

0,03 o.os 0,03 o.o3 o.oa 0,06 o,o3 Oo03 

o,o1 0,03 0,02 Oo02 Oo05 Oo03 o.o1 o.o1 

99,03 99,29 99.33 99.05 99.14 99,71 99.44 99ol6 

CIPW Norms 

0,071 0,569 0.223 Oo276 lo9l3 2o954 

7.161 5.237 5,057 5.310 2.682 5o808 6o656 6o317 

30,931 25,567 25,982 24.603 18,436 25.120 31.144 29.782 

22.472 26,415 25.444 27.407 27.274 22.193 27.348 30.245 

7,172 flo679 7,994 5o366 8,536 8olit3 6,378 4,403 

10.839 16.204 14.793 l4o860 22.383 6,182 9.449 8o866 

5,657 4,747 6,595 3ol16 4o234 

9,863 o.o12 

So479 Oo006 

6,691 9,206 7,824 7.099 10,080 5e947 6,590 6,238 

0,045 0,074 0,044 0.045 Ooll9 Oo089 0,044 0.045 

1,567 1.601 2.888 

7.211 6,810 6,482 6,500 5.287 6.286 6,494 6.301 

1,626 1.217 1,145 lo148 Oo860 lo402 1.477 1.409 

o.ou 

o.023 

99,876 99,544 99,734 99,209 99,172 99,668 99,833 99,448 

60,635 57.788 56,706 57.596 50,305 53,120 65,148 69,298 

39,241 41.756 43,029 41.613 48,867 46,548 34.685 30o150 

13.924 12,452 15,329 10.372 15.914 15.794 12.330 8,208 

7,172 6,679 7.994 5.366 8.536 8,143 6o378 4,403 

4,436 5,773 5,!)53 3,467 7.378 5.087 4ell1 3,805 

2.315 1,782 lo539 2,564 1.842 

9,745 10.431 12.205 16.449 15,005 1,648 7,731 So061 

6,403 10,431 9,240 11.393 15,005 1,096 So339 5,061 

3,342 2,965 5.056 Oe552 2.392 

15.342 0.019 

9,863 Oo012 

5o479 Oe006 

KLPA-31 KLPA-32 

X y 

46,30 4!),82 

16.58 12o68 

3,32 6o08 

9.54 7o35 

s.ss 1lo24 

8.73 9etl4 

3,17 2o27 

1.10 Oo63 

0,85 Oo56 

lo47 2o6l 

Oo(,2 Oo32 

0.20 Oo20 

0.03 Ooll 

o,o1 o.os 

9Qo47 99.!;;6 

6o535 3o739 

26.967 19o293 

27.910 22.648 

4.826 9o724 

6,415 l8o083 

4.367 2o925 

5.243 7o032 

3.933 1o254 

4.839 8o854 

0,044 Ool63 

6,625 4t979 

1.476 Oo761 

99.180 99o'!-5!) 

61.411 45.680 

37.769 53,774 

9o444 18o416 

4,826 9o724 

2.748 7o482 

1.870 lo2ll 

6,164 12.315 

3.~67 l0o601 

?,496 lo715 

9,}75 8o285 

5,243 7e032 

3.933 1·254 

KLPA-33 

z 

51,40 

17,67 

5,11 

4,95 

2,97 

6,04 

5,08 

2,00 

0,38 

2,34 

1,09 

0,21 

0,03 

0,01 

99.28 

11,904 

43,297 

19,646 

1,404 

7,432 

1,393 

0,013 

0,003 

7,463 

0,045 

4,476 

2,600 

99.676 

74.847 

24.829 

2,665 

1,404 

1.062 

0.199 

7,564 

6,370 

1,194 

0,016 

o.o13 

0,003 

t-3 

> td 

t"" 

t_%j 

r::J) 

r 

-.J 

C/.j 

-:) 
TABLE 2.-Chemical analyses of rocks on a phenocryst-free basis from the Kalaupapa section 

[Localities A-Z are shown in fig. 3. Values determined by subtracting phenocrysts from the dry-reduced whole-rock compositions on the basis of modal amounts (fig. 5) and compositions of the phenocrysts (tables 3--7)] 

KLPA-1 KLPA-2 KLPA-3 KLPA-4 KLPA-5A KLPA-7A KLPA-8B KLPA-9A KLPA-11 KLPA-l4A KLPA-l5A KLPA-l6A KLPA-l6B 

A B c D E F G H I J K 1 M 

Chemical analyses (weight percent) 

Sl02 48o68 46,39 48.47 49.58 47.93 47.30 48.38 47,78 47.65 47.45 48.67 47,60 47o60 

AL203 15o29 15,79 15.40 14.04 15,61 16.13 16.62 16.91 16.56 15.25 14.76 14.85 l6o09 

FEO 12.08 12.46 11.73 13.00 10,3A 12,46 10.50 11.05 13.01 12.94 13.09 11,3, 10o96 

I"IGO 5o63 7.41 7o85 s.es 8.73 6,15 6.26 6.49 4,23 6,35 So03 6.91 6o36 

CAO 10o86 11,31 10. 7l 10.24 11.93 10.14 llo67 11.22 l0o43 10.43 9.83 11.63 10.94 

NA20 2o95 2,41 2.27 2.61 2.04 3.19 2.70 2.66 2.91 2o96 3o25 2.84 2o94 

K20 Oo&2 0,25 Oo18 Oo67 Oo19 0,73 0.36 0.32 0,49 Oo48 o.87 o.as Oo89 

TI02 3o2l 3,37 2.76 3,34 2.56 3,22 2o85 2,90 3,92 3,43 3o 71 3.27 3o43 

P205 Oo46 0,34 Oo35 Oo42 0.29 0,46 Oo36 0,37 Oo54 0,47 Oo56 Oo43 Oo53 

MNO Oo18 0.17 0.18 0.20 OolS 0,18 Ool4 Oo14 Oo19 Ool9 o.zo Ool1 Ool7 

CH203 Oo03 0.11 0.07 o.oJ 0,14 0,03 Oo13 0,13 Oo06 o.o3 Oo03 Oo09 OolO 

NIO Oo02 0.02 0,04 0,02 Oo03 o.o3 o. 01 OoOl 

TOTAL 99.99 1oo.o1 99o99 100.00 99o99 lOOoOl 100.00 100.00 99.99 99,99 100,01 loo.oo 100.01 

CIPW Norms 

OR 3o664 1,477 lo064 3,959 1.123 4.313 2.127 lo89l 2.896 2.837 5.141 5,023 So259 

AB 24o965 20,391 19.210 22,085 17.264 24,795 22.847 22.508 24.626 25.049 27.498 20,965 23o818 

AN 26o650 31.525 31.302 24,615 32,878 27.534 32.166 33.255 30.679 26.909 23.114 25.261 28o075 

NE 1.189 1.661 Oo573 

wo 10ol16 9,335 8o162 9,788 10.195 8,251 9.761 8.347 7.324 9.089 9ol82 12.370 9o491 

EN 7o428 6.695 14.081 12.689 12.974 3,774 8o397 7.665 6o777 So562 6o005 6.310 4o809 

FS 9o107 6,362 12.454 16.319 8,987 4.412 7.958 7.446 llo399 6o486 8.760 5.757 4o460 

FO 4o621 8.239 3o834 1.318 6,146 a.oae 5o041 5.956 2o634 7.186 4.570 7e638 7o729 

FA 6o244 8.629 3.737 1oB68 4,692 10.421 5.265 6,376 4o882 9,235 7.346 7,678 7o900 

CM Oo044 0,162 Oo103 Oo044 0,206 0.044 0,191 0.191 o.oaa 0.044 0.044 0.133 Ool47 

IL 6o097 6.400 5o242 6o343 4,862 6,115 5.413 s.soa 7.446 6,515 7.045 6.210 6o514 

AP 1o090 o.8os Oo829 0.995 0.687 1.089 Oo853 0.876 1.279 lol13 lo326 le018 lo255 

TOTAL 100.026 100.020 100.019 100,023 100.015 100.025 l00o019 100.020 100.030 100.026 100.031 100.024 100.029 

SALIC 55.278 53.393 51.576 50.659 51.265 57.832 57.140 57.654 58.201 54,795 55.752 52.910 57.724 

FEMIC 44,747 46,627 48,443 49,364 48,750 42.193 42.879 42,365 41.829 45.231 44.279 47ol14 42.305 

DI 20ol83 18.467 16ol08 19.561 19.962 16,436 19.307 16.523 14.770 18.105 18o428 24.437 18o760 

OhiO 10o116 9.335 8o162 9o788 l0ol95 8.251 9.761 8,347 7o324 9,089 9.182 12.370 9o49l 

DIEN 4o523 4,682 4o216 4.275 5.770 3.774 4o901 4o147 2.776 4.162 3.761 6o310 4o809 

DIFS 5.545 4.449 3o729 5,498 3,997 4,412 4o645 4.029 4o670 4,854 5,486 5,757 4o460 

HY 6o468 3,925 18.589 19.235 12.194 6o810 6o934 10.730 3.033 5.519 

HYEN 2o906 2.013 9o865 8o414 7.204 3o496 3.517 4o001 1.400 2.245 

HYFS 3o562 1,913 Bo725 10.821 4o9'il0 3o313 3.417 6.729 1.633 3o274 

OL l0o865 1·6,868 7o572 3o186 10.838 18.509 10.306 12.332 7.516 16.421 lle91ll 15.316 15o629 

OLFO 4.621 8.239 3o834 1.318 6,146 8,088 5,041 5,956 2.634 7.186 4.570 7.638 7o729 

OLFA 6.244 8,629 3.737 lo868 4,692 10,421 5.265 6,376 4e882 9,235 7.346 7.678 7o900 

Cl.:l 

00 

trJ 

~ 

rn 

>-3 

~ 

0 

t"" 

0 

~ 

~ 

< 0 

r 

0 

~ 

z 

0 

rn 

trJ 

:;:o 

...... 

trl 

rn 
TABLE 2.-Chemical analyses of rocks on a phenocryst-free basis from the Kalaupapa section-Continued 

ICLPA-17A ICLPA-19B KLPA-19D ICLPA-20A ICLPA-23B KLPA-25A KLPA-27 ICL!'A-28 KLPA-29 KLPA-30 ICLPA-31 

N 0 p Q R s T u v w X 

Chemical analyses (weight percent) 

5102 48,01 48.56 48.74 47.05 47.90 47,76 47,59 46,85 47,39 47,41 47,36 

AL203 15.58 15.80 1~.19 16,20 15.43 16.01 16.57 15,35 13,90 15,43 11.28 

FEO 10.77 13.29 12.95 12.82 12,84 13,25 12.39 13.36 14.67 14.44 12.i?4 

MGO 6,30 4.03 4.44 5.53 5.99 6,05 5,42 4.72 4.69 4.32 5,05 

CAO 11.48 8,36 8,78 9,60 9, 71 8,87 10,56 9,76 8o61 e.u 9,10 

NA20 2,89 3.67 3,70 3,20 3,10 2.95 2.69 3o52 3.57 3.44 3,32 

K20 o.8s lo27 1.27 0,95 0,86 0.91 Oo58 1o25 1.43 lo34 1,15 

Tl02 3,37 4,03 3.9& 3.85 3,44 3,47 3,44 4,18 4,58 4,41 3,62 

P205 0,46 0,72 0.72 Oo55 0,49 0,49 0.47 Oo76 0,84 0,80 0,65 

MNO 0,15 Oe22 o.c1 0.17 0,19 o.19 0,19 0.19 0.25 0.24 Oo20 

CR203 0,11 o.o3 0.03 0.05 0,03 0,03 0.06 0,06 0,04 0,04 0.03 

NIO 0,02 OoOl o.o1 0,02 0,02 o.oz 0,03 o,o1 o.o1 0.01 

TOTAL 99o99 99o99 100,00 99.99 100,00 100,00 99,99 100.00 99,98 99,99 100.01 

CIPW Norms 

OR 5,023 7.506 7,505 5.614 5,082 5.377 3,428 7.387 8,452 7,919 6,795 

AB 23,520 31.058 31.308 2f•.Ol8 26,231 24.962 22.764 24,321 28.412 29.111 27,392 

AN 27,031 22.889 21.088 27.036 25.647 27.755 31.428 22.392 17,683 22.706 28,848 

NE 0,507 0,576 2e960 0,977 0,378 

wo 11,241 5o797 7.418 7,098 8.068 5o448 7.472 Bo794 8o163 5.138 5.030 

EN 5. 715 3,280 3.157 3.120 4,678 5,949 7.213 3.517 3.019 2.952 2.152 

FS 5,256 So932 5.032 3.962 5.726 7.487 9,312 5.366 5.225 5,396 2.885 

FO 6,991 4.735 5,536 7,466 7.176 6.390 4,406 5.773 6o029 5,471 7.305 

FA 7,087 9o438 9.724 10.450 9,680 8o863 6,268 9,705 11.277 llo 020 10.793 

CM 0,162 Oo044 0.044 0.074 0.044 Oo044 0,088 Oo088 0.059 0.059 0,044 

IL 6,401 7.655 7,521 7,313 6,533 6,590 6,534 7.939 8,700 8,376 6,874 

AP 1,090 1oT06 1.705 1.303 1.161 lol61 1oll3 lo800 le990 1o895 lo539 

TOTAL 1oo.o25 100.039 100,039 100,030 100,027 100.027 100,025 100,042 100,046 100.044 100.036 

SALIC 56.082 61,453 59,901 59,244 56,960 58.095 57,620 57,059 55,523 59,736 63.413 

FEMIC 43,943 38.587 40,138 40.786 43,067 4lo932 42,405 42,982 44,523 40,308 36.623 

DI 22.212 11.719 14.933 14.180 16,097 10.880 14.934 17,678 16.468 10.390 10.067 

OhiO 11,241 5,797 7,418 7,098 8,068 5.448 7.472 8,794 8.163 5,13A 5,030 

OlEN s. 715 2.109 2.897 3.120 3,610 2,405 3,257 3.517 3,079 1.857 2.152 

DIFS 5,256 3,813 4,617 3.962 4.419 3.027 4,205 5,366 5.225 3.395 2.885 

HY 3.291 0,675 2.376 8.004 9.062 3.096 

HYEN 1.172 0,260 1,068 3.544 3.956 1.095 

HYFS 2ell9 0,415 1.307 4.460 5.107 2,001 

OL 14,078 14.173 15.260 17,916 16.855 15,254 10,673 15.477 17.306 16.492 18.098 

OLFO 6,991 4,735 5,536 7,466 7,176 6.390 4,406 5.773 6.029 5.471 7,305 

OLFA 7,087 9o438 9.724 10,450 9,680 8o863 6.268 9,705 11.271 llo020 10.793 

KLPA-32 

y 

47.98 

15o47 

12e21 

5.34 

lle57 

2e78 

Oo77 

3·17 

Oo40 

Oe18 

Oe12 

99.99 

4o551 

23.526 

27e461 

llo4ll 

5o281 

6e917 

5e620 

8oll1 

Oo177 

6o021 

Oo948 

100.023 

55.538 

44.485 

22o820 

11·411 

4o940 

6o469 

Oo789 

Oo342 

Oo448 

l3o731 

5o620 

8oll1 

ICLPA-33 

z 

52,41 

18.13 

9,44 

2.78 

6,19 

5,21 

2.05 

2,41 

1,12 

0,20 

0,03 

0,01 

99.98 

12,116 

42,619 

20,032 

0.799 

1,404 

0,484 

0,959 

4,514 

9,856 

0,044 

4,578 

2,653 

100.060 

75.567 

24,493 

2,847 

1,404 

0,484 

0,959 

14,370 

4,514 

9,856 

t-3 

> b:l 

t""' 

t;rj 

w. 

,.... 

I 

-..:] 

Co.~:> 

~ 
TABLE 3.-Chemical analyses of olivines from the Kalaupapa section 

[Localities A-Z are shown in fig. 3. Plotting symbols are p=central part of phenocrysts, r=rim of phenocrysts but inside the alteration rim, if present. c=central part of an olivine grain in a cluster, g=groundmass olivine, and 

o=fresh overgrowth on olivine phenocryst, in cluster or altered groundmass grain] 

A B c D 

I •lPC •lPfO -2PC •2PEO •3MPF 1 •!PC •lPE •2PC I •!PC •i!PC •36 I -tcr. -cE'o p 0 p 0 0 p r p p p g c 0 

5102 38o70 36,20 39.70 36,80 36,60 39.20 38.50 39.30 39,70 39.10 36.40 3Aol0 35o70 

AL203 Oo06 o.o7 OoOft o.o7 o.oQ 0,04 o.o4 o.oe 0.12 o.o7 Ooll o.oA Ooll 

fEO 19ol0 36.40 lAolO 33.20 35,40 19,30 22.20 16.40 12.50 18.50 34.30 ~t.An 36o90 

MGO 40o70 26.00 42.20 29.20 27.10 40,60 37.80 42.90 46o00 40.90 27.JO 37.80 25o00 

CAO Oo38 0.47 Oe40 Oo48 0,47 0.38 Oo33 Oo33 0.31 0,36 n.sz 0.39 Oe48 

TI02 o.os 0,09 0.03 0,10 O,OR 0.03 o,04 0,04 o,oJ o.o3 o.o7 0,06 Oo2S 

MNO Oo30 0,59 Oo27 o.s7 o.s. 0.31 Oo41 0,26 0.20 0.28 0,47 0,36 o.so 

NIO Oo30 0,23 0.30 O,?b 0,?4 0,29 o.27 0.41 Oo41 0,24 0,29 0,26 Oo22 

CR203 OoOJ 0,04 0.04 o.o4 0.04 0.04 o.04 0,04 0,07 Oo03 o.os 0.03 Oo04 

TOTAL 99,62 1oo.o9 101.10 100,72 lno,c;6 100,19 99.63 99.76 99.34 99.51 99,51 9Ae8A 99.20 

D (c ont'd) £ F G I 

-2G I L•1PC L•2PC I L•l_CC L-2PC I L•lPC L·1PE L•2PC L•?PE L•3G I L•IPC L•lPE L•2CC g p p p c p r p r g p r c 

5102 36,20 39.00 39.40 3R,SO 39,00 39,10 3E!,20 37,60 37.70 35.30 JA,?O 31h40 37.30 AL203 0,10 0.06 0,06 o.o1 o.os Oo07 0.11 0,06 0,(16 0,10 o.ns Oo09 0,10 fEO 33,60 16oAO l4,AO 19.90 18.80 21.80 18.40 20.10 19o40 39.20 21.?0 2lo20 22,10 MGO 27,90 42.00 44.00 39,60 40,90 39.20 41.20 39,40 39oRO ?.3.80 38,AO 3Bo80 37,40 CAO o.~l 0.37 0,25 0.41 0,38 0.47 o.s4 0,47 Oo44 0,53 0,49 Oo5l 0,48 TI02 0.12 0.03 0.03 o.oc; 0.04 o.o4 0,04 o.o• o.n3 0.14 o.n3 Oo05 0,04 MNO 0,48 0.26 0.24 o.zq 0.29 Oo33 0 .31' Oo33 0.31 1),74 o.~~ Oo3l 0,34 NIO 0.21 0,29 0.33 0,27 0.30 0.24 o.za 0.30 Oe24 Oo23 0.26 Oo30 0.24 CR203 0,04 Oo04 0,03 o.o1 0.03 o.02 0,04 o.02 0.03 0.04 0.03 Oo04 0.03 TOTAL 9Q.l6 98o8S 99,14 Q9.12 99.79 101.?7 99.12 98.32 98.01 lOO.OFI 99.~9 99.70 9Ro03 

I (cont'd) J K L 

L-:wc L•4G I OL-1P OL•lP OL1PE OL-2C OL-3G I OL•lP OL•1P OLIPE UMPE I OL-lP OllPE p g p r 0 c g p r 0 0 p 0 

SIOZ 39.10 36.00 3R,60 38,30 35.90 38.60 37,00 38,70 ~FI,80 3S.RO 36ol0 3A,70 34oRO 

Al203 o.os 0.10 o.o~ 0,09 o.os 0.10 o.1s 0.10 0,09 0,08 Oo07 0,06 Oo07 FEO 17.00 34.50 19.00 18.80 37.90 18.50 35.00 18,90 18.70 35.60 36o90 20,10 39.20 

MGO 42.00 27.20 40.80 40.30 24.20 41.10 27.70 40.70 40.90 26.60 26e10 40.00 22.70 

CAO 0.47 0.67 0.47 0.45 Oo59 0.47 0.61 0,47 0.49 o.c;1 Oo60 o.4a Oe63 

TI02 Oo04 0.14 o.oJ 0,03 o.oe 0,03 0.11 o.o4 o.o3 OelO o.oa o.o4 OoOR MNO 0,28 o.so 0.29 0.27 0.60 0.27 0,54 0.31 0.29 0.59 Oo59 0.31 0.56 

NIO Oe32 Oo26 o.3o 0.27 o.2:!' 0,26 0.25 0.28 o.u. 0.2~ Ool9 0,30 o.zo 

CR203 o.o., o.oJ 0,04 0.04 Oo04 o.o3 0,04 0,04 o.o3 0,04 Oo03 0,03 Oo03 

TOTAL 99.31 99,40 99,c;9 98.55 99.58 99,36 101,40 99,54 99,59 99o6l 100.66 1on.o2 9A.27 

~ 

0 

trj 

> rn 

t-3 

~ 

0 

t'"' 

0 

~ 

> 

"""" 

< 0 

t'"' 

(1 

> z 

(1 """" 

rn 

trj 

:::0 

"""" trj 

rn 
TABLE 3.-Chemical analyses of olivines from the Kalaupapa section-Continued 

L (co nt'd) M N 0 p 

OL-2G I Ol.-1P OL•ZP L3MPE I OL•lP OL•lP I OllPE OL•2G I OL-2r. I OL•lP g p p 0 p r 0 g g p 

5102 36.10 37.80 38.70 35.90 38,50 38o4t0 35oOO 35.20 35.60 38o00 

AL203 DolO o.o~; 0,06 Oo09 o.os Oo06 Oo09 Oo10 Ooll Oo04 

FEO 34.30 24,20 17.30 37,00 23,40 23.20 38.30 40,90 38,70 23o60 

MGO 27.40 36,00 41,90 25.20 37.80 37o80 23.90 23.00 24.~0 37o40 

CAO 0,60 0,4R 0,47 Oo66 0,56 Oo49 o. 71 Oo65 0,72 o.so TI02 o.oa O,OA Oo04 Ool3 Oo04 Oo04 0.06 Oo12 o.n o.os MNO 0,42 o.3e 0.27 Oo63 Oo37 Oo36 0,68 o,6c; o,se Oo40 

NIO 0,24 o.zz 0.32 0.21 0,25 Oo22 0,18 o.zo n,zo Oo20 

CR203 o,oJ o.oz Oo04t o.os Oo03 Oo03 0.04 Oo04 0.04 Oo02 

TOTAL 99,27 99.22 99.10 99o87 101,00 100,60 98,96 100oR6 100.62 100.21 

Q(cont'd) R s T 

OL~Gf 1 OL•1G I L1MPE OL-2G I L•lPC L•lPf L.•2PC L•2PE L•3G I L.•4CC 0 g 0 g p r p r g c 

5102 36.6"1 35.70 36.30 36,30 38.50 39o30 3Po50 :38.50 39o40 38,30 AL203 Oo24 0,78 o.oa o.oa 0.04 OolO Oo04 OolO Ooll 0,10 FEO 36,00 37.20 35.70 36.20 20o00 l7o30 22.90 23,00 l8o50 21.50 MGO 24.70 25.90 27.60 27.00 40.60 42.50 37.80 37,60 4lo00 39,00 CAO Oo69 0,66 Oo65 0.62 0,37 Oo41 0,42 o.ss Oo55 0,43 TI02 Oo17 0.18 Oo07 o.o8 Oo04 o.os o.os 0,05 Oo06 0,06 114NO Oo61 0,60 Oo66 0.56 Oo32 0.34 n.36 Oo33 Oo3l 0,34 NlO Oolt. 0,20 o.21 0.24 Oo31 0,37 Oo29 o,?7 Oo34 0,27 CR203 0,03 o.02 Oo03 0,04 0.04 o.o3 o,o3 0.02 Oo05 0,04 TOTAL 99,20 101.24 101.30 101,12 100,22 100,40 100.39 100.42 100.32 100.04 

U (cont'd) v w X 

L-2PC L•2PE L·2PE L-3GE I LlMPE L•2GE I L·2GE I L•2PE L-3GE I L•lPC 

p r 0 0 0 0 0 0 0 p 

SI02 38.20 38,40 36,50 35,90 35,80 35.80 35,80 36ol0 35,30 39.80 

AL203 0,01 o.os 0,06 o.1o 0.10 Oo08 0.11 loll 0,11 o,o8 

FEO 21.30 22.20 34,70 39,80 40.00 41.80 40,20 40el0 41,90 14.30 

MGO 39.10 38.40 27.60 22.60 22.80 2lo30 22.90 23o40 21.90 45.10 

CAO 0,44 0,41 o.so 0,66 0,57 0,59 0.67 Oo64 0,64 Oo35 

TIOZ o.os o.os 0.14 Ool6 0.12 0.21 0.11 Ool9 0.13 o.o3 

MNO 0,35 o.36 o.ss 0,83 0,68 0.10 Oe72 Oo73 0,69 o.25 

NIO 0,24 0.20 0.22 0,16 0,17 Oo18 Ool6 o.1s 0,15 Oel9 

CR203 0.03 Oo03 o.os o.o3 0.03 0,03 0,04 Oe03 0,03 Oe06 

TOTAL 99,78 100.10 100.32 100.24 100.27 100,69 100.71 102.45 100.85 100o36 

Q 

OL·lP OL•2C 

r c 

38.10 3Ro60 

0.04 0 oll 

23.80 19,80 

37,30 40.30 

o.sl 0.!;3 o.os o.o3 

0,40 Oo30 

0,21 Oo25 

0,03 Oo03 

100o44 CJ9o95 

u 

L•lPC L-lPE p r 

3Ro20 38,60 

o.os Oo07 

23o10 22.90 

37.60 37.50 

0,45 0.44 

Oo06 0,06 

Oo38 0,36 

0,26 0,21 

Oo03 o.oJ 

100.16 100.17 

y 

L•2GC I L•1MP 

g p 

39,40 37,50 

o.u o.1n 

17 .oo 28.10 

42,80 33.40 

0,43 Oo4l 

0,06 o,oc; 

0,28 0,11' 

0,24 Oo09 o.os 0,03 

100.37 100.46 

OL .. 3G 

g 

38,60 

OolO 

18.10 

41.00 

0,48 

Oo06 

Oo24 

0,34 

o.oz 

98,94 

L-1PF 0 

36,60 

Oo07 

37.10 

24,9n 

0.62 

O,liJ 

0,11 

o.lR 

o.o:l 

100.39 

z 

L•2MP 

p 

37.20 

0 oll 

29,60 

32.10 

0,44 

0.06 

o.es 

o.u 

Oo03 

100.50 

~ 

;J;>-

ttl 

~ 

t;rj 

w 

1-' 

I 

-.J 

L•3G I g 

35.90 

o,19 

35,00 

26.30 

Oo64 

o.12 

lo10 

o.12 

o,04. 

99 .• 41 

~ 

1-"' 
TABLE 4.-Chemical analyses of olivine alteration rims from the Kalaupapa section 

[Localities A-Z are shown in fig. 3. Plotting symbol i =inclusion in olivine] 

A B 

I 1•1PI l•!PI l-2PI 1•2PI 13MPI 13MPI I 2•1PI 2•1PI 2,.2Pl i i i i i i i i 

SI02 37ec0 37.20 37.60 37.60 36.80 36.80 36,50 36,50 36.00 

AL203 0.39 0.39 0,20 0.20 0,38 Oo38 Oo76 0,76 Oo68 

FE203 30,40 25.30 32.80 30,20 

FEO 27o30 22o80 29.60 27.10 26,50 

MGO 28o00 28,00 36.60 36,60 26,80 26,80 30,70 30.70 29,70 

CAO Oo5l 0.51 o.s1 o.sl o.sc; Oo55 0,48 0,48 0,44 

TI02 Oo39 0,39 0.09 0,09 OoOA o.oe 0,09 0,09 0,06 

MNO Oo36 0,36 o.32 0,32 0,39 0,39 0,36 0,36 0,41 

CR203 o.os 0,05 0.03 o.o3 Oo04 Oo04 Oo04 0,04 Oo04 

NIO Oo26 0,26 0.28 0,28 0,2j) 0.22 0,25 0,25 0,23 

TOTAL 94,46 97.56 98o43 100,93 94,A6 98.06 96.28 99,38 94,06 

C~cont'd) 0 E 

3•2PI 3-?.PI I 4•1CI 4•1CI I 5R1PI SBlPI 5B2PI 5A2PI 5R3GI i i i i i i i i i 

510?. 34o60 34,60 36.70 36,70 35,80 35.80 37,10 37.10 36,40 

AL203 Oo53 0,53 Oo35 0.35 Oo6l 0.61 o,s7 0,57 Ool7 

FE203 36,20 31.50 31,30 22.80 

FEO 32o60 26.40 28.20 2o.so 27.10 

MGO 23o40 23,40 26.30 26.30 27.30 27.30 36.60 36,60 31.90 

CAO Oo52 0.52 0,60 0,60 Oo6? 0.62 Oo47 0.47 0,43 

Tl02 o.oa 0,08 0 oll 0 oll o.oc; o.os 0,07 o.o1 Oo06 

MNO Oo32 0,32 Oo4l 0,41 o.37 0,37 0,38 0,38 o.3A 

CR203 Oo05 o.os Oo04 Oo04 o.o, Oo06 o.04 0.04 o.o3 

NIO Oo26 0,26 Oo24 0,?.4 0.27 0.27 0.31 0,31 0.30 

TOTAL 92.36 95,96 93.15 96.25 93,?.8 96,38 96.04 98,34 96,77 

F{cont'd) G 

7A2PI 7A2PI 7A3GI 7A3GI f 8AlPT 8BlPI 882PI 8B2PI I llPIO i i i i i i i i i 

5102 15o60 35.60 35.50 35.50 34,40 34,40 34.00 34.00 33.40 

AL203 Oo56 o.s& 0.70 0,70 Oo60 OobO Oo54 0,54 o.s7 

FE203 38.40 38.30 37.00 37.00 

FEO 34o60 30o89 33.30 33,30 29.40 

MGO 22o00 22,00 24o80 24 0 AO 23.20 23.20 22.10 22.10 26.70 

CAO Oo67 0,()7 0.68 o.&A Oo6A 0,68 0,65 0,65 o.ss 

Tl02 Oo23 o.23 Oo23 0,23 0.17 0.17 o.ls 0.15 0,24 

MNO Oo39 0,39 Oo37 0.37 Oo4l 0,41 0,42 0.42 0.35 

CR203 Oo03 0,03 Oo03 0.03 o.oc; o.os 0.03 0.03 o.o• 

NIO Oo26 0,26 Oo22 0.22 Oo21 0,23 o.2a 0,28 0,22 

·TOTAL 94.34 9A o14 93.42 100.133 93.04 96.74 91.47 95.17 91,47 

2•2PI I 3•1PI i i 

36.00 34,00 

0,68 o.9a 

29.50 

33.70 

29.70 22,80 

Oo44 0.49 

Oo06 0,20 

0,41 0,36 

Oo04 0,05 

Oo23 0,28 

97,06 92,86 

5R3Gl I HlCI 

i i 

36,40 36.70 

o.n o.5e 

30,10 

23.70 

31.90 13.60 

Oo43 Oo45 

Oo06 Oo2l 

Oo38 o.?.A 

o.o3 0.01 

0,30 Oo27 

99.77 95,82 

llPIO llPII 

i i 

33,40 :n.so 

Oo57 ?o39 

32.60 

27.30 

26,70 24.60 

o.ss 0.62 

0,24 0.09 

Oo35 0,28 

o.o4 o.os 

Do??. Oo25 

94.67 87.08 

c 

3"'1PI i 

34.00 

0,9A 

37.40 

22,80 

0,49 

O.il'O 

0,3(, 

o.os 

0,28 

96.56 

F 

7AlCT 

i 

36,70 

o.r;e 

26,40 

33,60 

0.45 

0.21 

0.28 

0,03 

0,27 

9Ao52 

llPI t 

i 

3lo"i0 

2.39 

30.40 

24,60 

Oe62 

o.o9 

o.?a 

o.o5 

0,25 

90,Hl 

t+:>-

t....:l 

M 

~ 

w 

>-3 

~ 

0 

r 

0 

~ 

~ ....... 

< 0 

t-< 

0 

~ 

z 

0 

w 

M 

~ 

M ""'" 

w 
TABLE 4.-Chemical analyses of olivine alteration rims from the Kalaupapa section-Continued 

I {cont'dl J 

12CII 12CII 12CIO 12CIO 113PI ll3PI t 4AlPI 4AlPI I SAl PI SAl PI i i i i i i i i i 

5102 J2o40 32,40 33.90 33.90 33,50 33,50 34.40 34,40 34,70 34.70 

AL203 Oo90 0,90 o.so o.so 0,59 0,59 Oo46 0,46 0,46 0.46 

fE203 30,40 34.90 38.zo 34.10 32.30 

fEO 27o40 31.40 34,30 30,60 29,00 

MGO 27o30 27,30 24.90 24,90 21,60 21,60 23,50 23.50 26,90 26,90 

CAO Oo60 0,60 Oo62 0.62 0,54 0,54 0,53 o.s3 Oo56 0,1;6 

TI02 Ool7 0,17 Oo39 0,39 0.20 0,20 0,17 0.17 0.10 o.to MNO Oo33 0,33 o.s6 0,56 0.35 0,35 0,39 0,39 0,38 0.38 

CR203 0.04 0,04 o.os o.os Oo04 0,04 0,04 0,04 o.o3 0,03 

NIO Oo27 0,27 Ool7 0.17 Oo25 0,25 Oo26 0,26 0.24 0,24 

TOTAL 89.41 92.41 92.49 95,99 9l,:n 95.27 90,35 93,85 92,37 95.67 

M 

J 6AlPI 6~1PI I B1PII BlPII BlPIR BlPIR 6R2PI 682PI I AlP II AlP II i i i i i i i i i i 

5102 36o00 36,00 34,00 34.00 34.60 34,60 34.40 34.40 32.10 32.10 

AL203 Oo28 0,28 Oo82 0,82 0.79 0.79 o.61 0,61 1.23 1.23 

FE203 29,70 33.30 35.50 34,20 36.30 

FEO 26o70 30.00 32.00 30,80 32,70 

foiGO 31o70 31.70 25o40 25.40 23.70 23.70 24,50 24.50 23,50 23.50 

CAO Oo41:1 0,48 Oo59 0,59 o.7o 0,70 0,63 0,63 0,62 0.62 

TI02 o.oa 0,08 o.06 0,06 Ooll o.u o.l3 0,13 o.oe o,o8 

MNO Oo30 0,30 Oo36 0,36 0.41 0,41 Oo33 0,33 Oo4l 0.41 

CR203 Oo03 0,03 Oo02 0.02 0.04 0,04 0.03 0.03 0,03 o.o3 

NIO Oo27 0,27 Oo2?. 0,2?. o.2a 0.28 0.26 0,26 0.24 0,24 

TOTAL 95.84 9Ao84 91.47 94.77 92.63 96.13 91.69 95.09 90,91 94,51 

N ~con t'd) p a 

7A3GI 7A3GI I 91PIO 91PIO I OAlPI OAlPI 0A2CI 0A2CI A3GCI A3GCI i i i i i i i i i i 

5102 35o50 35.50 32.80 32.80 35,60 35,60 36.00 36.00 35,90 35,90 

AL203 Oo62 0.62 o.61 o.t.1 0,53 0~53 Oo55 0.55 0,64 Oo64 

FE203 33,10 31.00 29.40 38.90 30.20 

FEO 29o80 27.90 26.40 35.00 27,20 

MGO 26o30 26,30 25.00 25.00 31.20 31.20 24.80 24.80 28.90 28,90 

CAO Oo73 o.73 o.7o 0.70 o.sc; o.ss Oo60 0,60 o.74 0.74 

TI02 Oo3l 0.31 Oo21 0.21 Ool5 0,15 0.12 0.12 Oo3l 0.31 

MNO Oo5l o.sl o.56 0,56 0.34 o.34 Oo47 Oo47 0,37 Oo37 

CR203 Oo04 0,04 Oo03 0.03 o.o3 0,03 Oo03 o.o3 o.o3 o.o3 

NIO Oo27 0,27 Oo21 0.21 Oo2? 0.22 Oo22 0.22 0,28 0,28 

TOTAL 94.08 97.38 a8.02 91,12 95,02 98,02 97.79 101,69 94,37 97,37 

K 

A2MPI 

i 

35.30 

0.48 

28.80 

27.30 

0.63 

Oo14 

Oo43 

o.o4 

Ool9 

93.31 

N 

AJPIR 

i 

3~.10 

0,84 

29,80 

26o70 

0.61 

0,?.7 

0.36 

Oo04 

Oe23 

93.95 

0A3GI i 

3f,.20 

3o33 

'nolO 

2Ao90 

0.6:? 

0.25 

Oo38 

o.o3 

Oe1S 

96.99 

A2MP! i 

35,30 

O,lf8 

32.00 

27.30 

0,63 

0.14 

0,43 

o.o4 

0.19 

96.51 

A1PIR 

i 

35.10 

o.A4 

33,10 

;u ... 7o 

o.t.1 

0.?.7 

0.36 

o.o4 

0.23 

97.?5 

0A3GI i 

36,20 

3.33 

30.10 

28.90 

0,62 

Oo25 

0,3A 

o.oJ 

Ool8 

9c:Je99 

I 

~ 

> to 

t"" 

tr_j 

UJ. 

..... 

I 

-.1 

~ 

CJ:) 
SI02 

AL203 

FE203 

FEO 

MGO 

CAO 

TI02 

MNO 

CA203 

NIO 

TOTAL 

5102 

AL203 

FE203 

FEO 

MGO 

CAO 

TI02 

MNO 

CA203 

NIO 

TOTAL 

5102 

AL203 

FE203 

FEO 

MGO 

CAO 

TI02 

MNO 

CR203 

NIO 

TOTAL 

TABLE 4.-Chemical analyses of olivine alteration rims from the Kalaupapa section-Continued 

R T 

llMPCI lMPCI ( 271PI 271PI 274CI 274CI I 81PCI 

i i i i i i i 

34.70 

le02 

32.90 

24e00 

Oe66 

OelO 

Oo46 

Oo03 

0·19 

94.06 

34,70 

1.02 

36.50 

24.00 

0,66 

0.10 

0,46 

o.o3 

0.19 

97.66 

34.50 

o.s3 

32.30 

24.10 

0.63 

0.46 

0.46 

o.o4 

Oe25 

93.27 

34,!;0 

o.s3 

35.90 

24.10 

0.63 

0.46 

0,46 

0,04 

0,25 

Cl6,87 

35,8n 

0.69 

?9.00 

27.90 

0,6~ 

0,14 

0,35 

0,04 

o.2R 

94oR3 

35.80 

0,69 

32.30 

27~90 

0,63 

0,14 

0,35 

0.04 

0.28 

98.13 

35,40 

0,6, 

2fh60 

27.70 

o.61 

0,06 

0,39 

o.o3 

o.25 

93.70 

81PCI 

35.40 

0.66 

31.80 

27.70 

0.61 

0.06 

0,39 

0.03 

0.25 

96,90 

U (c o n t' d) V W X 

281Pl 

i 

35.80 

0,45 

29,90 

26.00 

Oo62 

0.09 

0,45 

0,03 

0.21 

93.55 

u 

281PI 

i 

35,RO 

0.45 

33.30 

26,00 

0,62 

0,(19 

0,45 

o.o3 

0.21 

96.95 

2a3GI 2A3GI r 291MP 291MP r-o!Pcl olPci -1 12Pc1 12Pcx 13Gcx 13Gci ' i i i i i i i i i i 

36.60 

o.~1 

28o40 

27o80 

Oo65 

Ool9 

Oo53 

Oo03 

Oo2l 

94.98 

36,60 

0,57 

31,60 

27,80 

0,65 

0,19 

0,53 

0.03 

0,21 

98.18 

Y(cont'd) 

322GI 

i 

36e50 

0.78 

3So20 

25.30 

Oo82 

Oo72 

Oo4l 

Oo04 

o.zo 

99.97 

32?.GI 

i 

36,50 

0.78 

39,10 

25,30 

0,82 

0.72 

0.41 

0.04 

0,20 

103.87 

35.10 

o.71 

30oAO 

25.20 

Oo57 

o.1o 

Oo55 

o.o3 

Ool6 

93o2Z 

35.10 

0.71 

34.30 

25.20 

o.s7 

0.10 

o.c;s 

o.o3 

0,16 

96.72 

z 

31.80 

1.76 

36.90 

21,50 

o.s1 

o.o9 

o,s.:; 

0,04 

o.1a 

93.33 

31.80 

1.76 

41.00 

21.50 

0.51 

0.09 

o.ss 

0,04 

0.18 

97.43 

I 31MPI 31MPI 32MPI 32MPI I i 

32.70 

lo25 

36o80 

20.90 

o.ss 

Oell 

Oo69 

Oo03 

0.13 

93·16 

i 

32.70 

1.25 

40,90 

20.90 

0.55 

Ooll 

0,69 

o.o3 

0,13 

97.26 

i 

34,70 

0,59 

35.10 

23.70 

o,sc; 

o.oe 

o,8c; 

0,04 

o.1o 

95o7l 

i 

34.70 

0.59 

39.00 

23.70 

o.ss 

o.oe 

o.8S 

o.o4 

0,10 

99o6l 

34.80 

loll 

30.10 

2t~.40 

0.47 

Oo22 

Oo40 

0.03 

0.19 

93.72 

34,80 

loll 

39,40 

26.40 

0,47 

0.22 

0,40 

Oo03 

0.19 

103.02 

35.20 

Oe45 

36.50 

24o00 

0,58 

Oo13 

0,47 

o.o3 

o.1s 

97.51 

35.20 

0.45 

40.50 

24.00 

o,s8 

Oell 

0.47 

o.o3 

0.15 

101.51 

282PI 

i 

3f>o00 

Oo54 

29.80 

2fo.,70 

0,57 

o,oq 

0.38 

0,03 

0.21 

94.32 

321PI 

i 

lf.oJO 

0.65 

2A.60 

2Ao70 

n.62 

0,19 

0.37 

o.oJ 

Oo18 

95.64 

y 

28?PI 

i 

36.on 

0,54 

33.10 

26.70 

O,!:i7 

0.09 

o.~R 

o.o3 

0.21 

97.6? 

321PI 

i 

36.30 

0,65 

31.70 

28.70 

0.62 

0,19 

Oo31 

n.oJ 

0.18 

9Ao74 

.,j:::. 

.,j:::. 

t.::z:J 

> r:n 

--3 

~ 

0 

t-t 

0 

~ 

::: 

< 0 

["4 

0 

> z 

..... 

0 

r:n 

t_l:j 

~ 

t_;j 

r:n 
TABLE 5.--Chemical analyses of clinopyroxenes from the Kalaupapa section 

[Localities A-Z are shown in fig. 3. Plotting symbols are p=central part of a phenocryst or microphenocryst, r=rim of a phenocryst or microphenocryst, c=central part of a clinopyroxene grain in a cluster, e=edge of a clinopyroxene 

grain in a cluster, and g=groundmass olivine] 

A B c 

I •1PC •lPE -2PC •2PE •3C I •lPC ·1PE -2PC •3PC -3PE •4CC -sr. I •lG t p r p r c p r p p r c g g 

5102 52e60 50.50 50.70 49.00 50.60 so.oo 51.50 49.50 50.10 so.so 4Q.60 50.20 49.90 

AL203 3e54 3.70 3.27 2oBl 2.6? 3.56 4.27 2.96 4.00 2.81 3.33 5,53 2o5l 

FEO 6.10 8.60 8.7o s.oo 9.on 7.50 7.10 7,40 7.00 8,70 7.80 9,70 l2o00 

MGO l6ol0 15.30 15.80 15.20 17.30 15.80 17.30 15.60 15.70 16,20 lllio60 15.60 l5o50 

CAO ?.0o80 19.60 20.20 19.70 18.50 20.90 19.70 20.70 21.00 18,90 20.80 2o.no 16o50 

NA20 Oo32 o.36 Oo33 Oo39 o.31 o.34 o.J5 0.34 0,33 0.38 o,34 0.37 Oo25 

TI02 1o04 1,78 1.51 1.63 1.01'1 1.35 1o70 1.28 1.26 1,43 1.32 2.oo lo23 

MNO Ool3 0.21 0.1~ 0,20 0.1A o.1s 0.24 0,16 o.1s 0.23 o.16 0.24 Oo28 

CR203 0·64 o.zo Oo08 0.06 0.14 0,20 Oo03 0.10 Oo45 o.oJ o.12 0.06 OolA 

TOTAL 101.27 100.25 100.77 96.99 99.71 99.80 102.19 98,04 99.99 99.18 99.07 103.70 98.35 

0 E F 

I -lCC -zcc •3PC -4PC ·5G t X•lPC X•2PC X•2PE X•3PC X•4PC X•M f X•1PC X•2PC 

c c p p g p p r p p g p p 

5102 52.10 51.60 48.30 4R.90 48.20 52.00 49.70 50.00 50.10 51.20 52.01) 50o40 51.50 

AL203 2,94 2o8A 4.85 4.05 2.76 3.15 3.59 3.49 3.17 s.oe 2.33 3o26 4.00 

FEO 7.50 7.90 9.50 9.lo 11.20 6.40 6.10 7,90 6,00 6.10 10.50 7o80 7.70 

1'4GO 16,60 16.30 15.50 lf-.10 14.80 17.10 16.70 16.60 16.60 17.70 16.40 16o20 16.00 

CAO 20,40 20.30 19.20 1~.60 17.50 20,00 20.00 19.20 19.80 20.00 18,50 20o30 21.10 

NA20 0.28 0.30 0,32 0,26 0,27 Oo24 0.27 Oo26 0.29 0.26 0.14 Oo35 o.35 

TI02 1,06 lo08 2.07 1.5c; 1.52 0.92 0,78 1.14 0,89 1.14 o.~6 loll 1.19 

"'NO 0,18 o.n 0.1 .. 0.21 0.2& o.1s 0,13 o.21 0.16 o.ts o.~z Ool7 0.16 

CR203 0.18 Ool6 0,14 0,12 o.o'+ o.31 0,49 o,oJ 0.24 0.61 0,05 o.Js 0,34 

TOTAL 101.24 100.69 100.06 98,89 96.55 100.27 97.76 98,83 97.25 102.24 101.10 99.96 102.34 

F (c on t' d) G I J 

X-2f'E X•JG I X•lP~ X·lPE X•2PC X•2Pf. x-3cc X•4G I X•lPC X•lPE x-2c X•3C ' PX•lP r g p r p r c g p r c c p 

SI02 49,50 49,30 51.70 50.30 51.00 51.60 51,30 51.30 51,90 50,50 50o90 51.10 c;},30 

AL203 3.02 4.20 3.52 3.97 3.48 2.52 3.15 3.23 3.62 2.78 3o65 3.86 3.96 

FEO 8o90 9,AO 5.90 8.60 7.60 9.30 6,90 7.40 5.70 11.10 7o20 6.70 s.3o 

MGO 14.30 14.30 16.20 15.00 15.00 15.70 15,50 16.00 16.30 14,30 15·60 15,40 16.10 

CAO 20.60 20.'50 21,20 19.30 21.20 19.40 20,70 20.30 20.50 18.90 21·10 20,90 21.10 

NA20 Oo36 0,41 0.3115 0,37 0,40 0,32 0,35 0.41 n,31 o.J5 Oe36 0,36 0.32 

TI02 1o66 ~.42 0,95 1 0 EIO 1.45 1.47 1.22 1.:n 0.87 1.58 1o46 1.44 1.89 

MNO Ool8 0.16 Oo1'5 0.25 o.zo 0.22 o.n 0.28 o.ts 0.13 o.n o.16 Oo13 

CR203 Oo07 0.10 o.6c; o.oe Oo16 o.o1 0.21 o.o4 Oo6? 0.64 Ool8 0.33 o.12 

TOTAL 98.59 101.19 100ofol2 99.67 100.49 100,60 99o50 100,29 99,97 100o28 100o62 100.25 100.82 

1-3 

> td 

t"' 

t:z:j 

(/) 

1-' 

I 

-.J 

~ 

Ol 
TABLE 5.-Chemical analyses of clinopyroxenes from the Kalaupapa section-Continued 

J(c o n t' d) K 

I -----

PX?.PC PX3Cr. PX3CE PX4CC PX4CE PX1CC PX1CE XlCE2 PX•2C PX3CC 

p c e c e c e e c c 

Sl02 50.90 50.20 r;0.40 51.30 50.20 51.10 50,30 50.40 50.70 5lo50 

AL203 3oF10 4.20 2.41 3.76 4,24 2.82 1.,1 2,40 3.A4 2o50 

FEO flo60 ~.to 13.50 6.00 9.10 7.50 14.30 12.70 7.40 7o60 

MGO 15,60 ts.on 13.40 15.90 15.00 15.70 12.40 13.50 15.50 lf,. 0 0 

CAO 20.70 19.70 18.70 21.30 19.70 20.40 18.20 lFioSO ~0.60 20o60 

NA20 0.36 0.36 0.37 0,33 0.38 0.36 0.35 0,46 0,38 Oo37 

TI02 1.3? 1.50 1.43 lol7 lo66 1.26 1.06 1.07 1.?8 1 o17 

MNO 0,16 0.14 0,31 o.ls 0.22 0,21 0.35 Oo29 0.16 Oo20 

CR203 0,39 Oo30 o.o1 0,64 Ool6 Oo18 o.nt Oo06 o.s:? Ool9 

TOTAL 99.83 97.50 100.53 100.55 100o66 99.53 98.58 99,38 l00o3A 100.13 

L(cont'lf) M 

PXlPF PX2PC PX2PE PX-3C PX-4C PX-5G I PX1PC PXlPE PX2PC PX-3C 

r p r c c g p r p c 

5102 "i1.oo 47.20 49.70 so.oo 47.40 48oOO '51.10 50.50 "i0o40 50.70 

AL203 3.00 7.10 2o86 4.89 6o80 5.30 2,76 ?..96 3o96 3,40 

FEO f:\,80 7,10 9.30 6.AO 7.30 9.oo 9.70 8.60 6o30 7.40 

MGO 14.10 14.00 13.40 15,00 13.90 13.80 14.50 14.10 l5o60 16,00 

CAO <?0,80 20.40 20.50 ?.O,M 21.00 20,40 ?0.30 20.90 21o00 19.90 

NA20 0.42 0,48 o.J9 0,40 0.40 0,45 0,48 0.43 Oo37 0,41 

TI02 1.60 2,60 1.74 1.44 2.45 2.51 1. 3?. loA9 lo42 1.38 

MNO Oo2? 0.16 0.22 0.16 o.l4 Oo?2 0,28 0.23 Oo14 0,18 

CR203 o.o. Oo45 o.os 0.44 0.21 Ool7 o.o? Oo45 0,23 

TOTAL 99o98 99.49 98.16 99,93 99.60 99,85 l00o44 99.83 99,64 99o60 

N (cont'lf) 0 p 

PX1PE PX2PC PX2PE PX-3C PX•4G I PX1CC PXlCE PX-3G I PXlPC PX1PE r p r c g c e g p r 

5102 50,30 50.90 51.20 48.20 47.00 c;o.?o 4A 0 FIO 48o30 50.60 49ol0 

AL203 2,95 4.26 1.99 5.97 s.~1 3o92 3a69 4o00 3,03 3o49 

FEO 9,10 5o 50 10.10 7.20 9.60 7,90 12.00 l0o40 8.40 10o70 

MGO 14.40 16.30 14.40 14.30 l3o10 14.90 12,90 l3ol0 14.80 l4o50 

CAO 20.90 21.30 20.20 21,60 20oAO 21.10 20.00 20o00 21.00 l9o50 

NA20 0.45 Oo35 0.61 o.42 o.so 0,46 0,45 Oo54 0.48 o.37 

TI02 1.79 o.~6 1.27 2.24 2.73 lo 77 2,5? 2o76 1,48 2o56 

MNO 0,23 o.12 0.30 0.17 Ool9 Oo16 0,?2 Oo21 0,26 Oo27 

CR203 o.o7 0.74 o.o2 0,45 0,04 Ool3 o.os Oo05 o.o1 o.02 

TOTAL 100.19 100.43 100.09 too.ss 99.77 100,54 lOOo63 99.36 lOOoOb 100o51 

PX1CE --------;;:-SG-1 e g 

49.50 51.30 

2.47 2.27 

12.90 10.90 

13.20 15.00 

19.30 18,90 

0.42 0.37 

1.39 lo40 

0.28 Oo25 

0,02 o.o~ 

99.48 100,47 

PX-4C PX-SG I c g 

49.70 49.80 

4o70 3,57 

1o00 8.70 

l4oBO 15.30 

20o90 19.40 

Oo37 0.42 

1o64 2.05 

Oo15 0,20 

o.3s 0.10 

99o6l 99,54 

0 

PX-2G I PX-1r, g g 

47,80 4R,4n 

4.37 ?,50 

11.20 9o90 

12.20 14.60 

19.30 20.40 

0.47 0.43 

2.97 1.59 

0,23 o.zc; 

0.05 o.o3 

98.59 98,10 

PX1PC 

p 

51.00 

4o36 

6.20 

16,00 

20.90 

0.36 

1.10 

0.15 

0,67 

100,74 

N 

PXlPC p 

c;o.so 

4.13 

fo,40 

15.40 

21.60 

Oo39 

1.30 

0.17 

0,45 

100.34 

PX-2G g 

48o60 

4.36 

9,50 

13.90 

20.20 

0.46 

2o82 

Oo21 

o.os 

100.10 

I 

t+;o. 

0) 

t:_%j 

> 00 

t-3 

~ 

0 

t:"" 

0 

~ 

> 1-< 

< 0 

t:"" 

0 

> z 

0 

00 

t:_%j 

~ 

;; 

00 
TABLE 5.-Chemical analyses of clinopyroxenes from the Kalaupapa section-Continued 

R s T 

f;X•lG PX•2G I PX .. lG PX•2G I x .. tPC X•lPF X"'2CC x .. 2cE X•3CC X-3CE g g g g p p c e c e 

SI02 48.40 50.90 49.40 50.90 50,30 5o.~o "i0o30 50.20 50.50 51.40 

AL203 4.90 4.07 4.29 2.04 3.80 2.32 3o80 2.83 3.71 2.20 FEO 9.10 10.70 9.60 a.eo 7,00 1n.c:;o 7o50 9.40 bo80 8,90 

MGO 14.30 14.20 u.oo 15.00 1t;,60 14,40 15·10 15.00 1"i,90 14.AO CAO 20.10 19.~0 19.30 20.?0 21.30 19,80 21ol0 19.80 21.10 19,70 

NA20 0,44 0,43 0,43 0.41 0,41 0,3R Oo42 0.36 0.35 0,43 

TI02 2.5<;1 loAl 2.13 1,45 1.26 t.sc; 1o62 1.81 1.21 lo?R 

MNO o.21 0.24 o.21 0.22 Oo16 0.13 Oo18 0,28 Ool7 0.?7 CR203 o.zo o.oz 0.15 o.15 0.32 0,19 Oo27 0.02 0.33 o.o2 TOTAL 100.24 102,17 99.51 99,17 100.15 100.07 l00o2~ 99.70 100.07 99.00 

{cont'd) v w X .. 2CE X•3G I X1MPC X1MPE x-?~ I X1MPC X1MPE X•2G X•3G I X•lG 

e g p r g p e g g g 

5102 48.90 4<;1,60 49,20 49,30 49.70 47o80 46,20 4R,80 50,60 46,90 

AL203 3,48 3.20 3,A2 l,27 3,01 5o09 5,82 3.76 2,69 c;,o, 

fEO 11.50 9o40 8.50 10.70 lO."iO 9ol0 14.00 11.20 10,50 9o71"l 1'4GO 12.00 14.10 14,40 13.?0 13.60 13o30 11.10 12.10 13.90 12.30 CAO 20,30 20.60 21.30 20.40 19,70 21·00 19.10 }Q,RO 19.30 ?0.60 NA20 o.se 0,48 0,46 0.48 0,3"7 Oo45 0. 71 0,65 0,41 0,56 

TI02 2.29 2,1'5 2o00 ?. • ?.? 1,92 2o89 2.67 2o4S 1,79 3,9A 

~NO 0.33 0,24 Ool9 o.za 0.27 Oo24 0,27 o.36 0.27 0,26 

CR203 o.ol o.o1 0,03 0,02 0.0?. Oo03 0.03 Oo03 0,04 0.04 

TOTAL 99,39 CJ9.78 99,90 99.87 99.09 99.90 9'ilo90 99ol5 99.50 99,40 

Y(cont'd) 

X•1CE X"'2PC X .. 2PE X"'3CC X-3CE X4MPC X4MPE X•5G I X•lG X•2G e p r e c p e g g g 

5102 48,70 49,60 49,40 49,90 49o00 51.60 47,90 47,00 51,0(1 51,60 AL203 3o85 4,97 5.39 4,47 4o76 2,83 bo29 6,72 2.68 2.03 FEO 11.00 7.Ao 8,40 6.90 9ol0 6,80 9.20 8.20 9,20 8,80 MGO 12.60 14.90 13.30 16.10' 1So30 15,50 }3.1 0 13.30 13.40 13,80 CAO 20.40 20.40 20.90 20.50 \9o40 19,70 21.oo 20.80 20.10 20,00 NA20 Oo49 0,35 Oo33 0.31 Oo29 0,?.9 0.38 0,39 0,74 0,64 TI02 2.28 1.79 ?,06 1.55 2o36 0,98 2o50 2.70 1.3(, 1.39 MNO Oo32 o.zo 0.19 0,20 Oo23 0,21 Oo20 0,22 0,4? 0,38 CR203 o.o4 o.•o Ool7 O,JA Ool9 0,32 o.za 0,19 0,02 0,03 TOTAl 99.68 100,41 100.14 100.31 100,63 98.23 l00o85 99,52 98,92 98,67 

X•4G I X•lPC g p 

c;o.8o 49.20 

?.86 4.97 

8.on 6,RO 

1';.40 14.60 

19.40 21,00 

0,35 0,46 

1.40 1.73 

o.JA 0,15 

o.o1 0,37 

QA,60 99.28 

X 

X•2G X·3G 

g g 

46.10 -H.2o 

s. 71 4.75 

10.20 to.oo 

12.00 12.30 

20.90 21o00 

0,57 o.ss 

4,05 3o60 

0,25 o.26 

0,03 Oo03 

99.81 99.69 

z 

PXlPC PX1PE p r 

49,90 49.60 

4.27 3.49 

7,90 12.RO 

15.30 12.40 

19.90 19.30 

Oo44 0,3A 

1o60 2.14 

o.2o 0.28 

0.21 o.os 

99.72 100.44 

u x .. 1PE 

r 

49,80 

3o2l 

8.20 

13.80 

21.20 

0.49 

lo72 

Oo17 

OolO 

98.&9 

y 

I X-ICC 

49,80 

4.54 

7.30 

15.40 

20,70 

0.35 

1.52 

0,19 

0,40 

100.20 

PX•2G I g 

49,50 

3.17 

13,90 

11.30 

19.80 

0,42 

1.97 

0,34 

Oo04 

100,44 

1-3 

> t:d 

r 

tz:j 

r.n 

..... 

I 

-.J 

~ 

-..l 
TABLE 6.-Chemical analyses of plagioclases from the Kalaupapa section 

[Localities A-Z are shown in fig. 3. Plotting symbols are p=central part of a phenocryst or microphenocryst, r=rim of a phenocryst or microphenocryst, c=central part of a plagioclase grain in a cluster, e=rim (edge) of a plagioclase 

grain in a cluster, and g=groundmass plagioclase lath) 

~ 

A B c 

I •1PC .. 1PE •2C •3MP -4G I •1PC •lPE -2cc "'2CE •3G I -lMP •2(; 1 p r c p g p r c e g p g 

5102 50.50 52.70 52.20 52.-;o 55.90 49.10 52.60 48.80 52.70 53.10 51.10 53.30 

Al203 30.70 30.20 29.60 30.00 27.70 31.80 29.50 31.60 27.40 28.80 30.20 29.10 

FE203 0·77 o.a9 0.83 0.95 1.2&; 0.78 1.C!o 0.89 1e24 1.16 o.78 1.01 

CAO 13·40 12.40 l2e30 12.80 10.40 14.60 11.90 14.90 12.20 12.20 13.40 11.90 

NA20 3e61 4.37 4o31 4.11 5.59 J.oo 4.64 2.83 4.57 4.64 3.88 4.82 

K20 Oe06 0.15 0.13 0.15 0.39 o.o4 o.2s o.oa 0.30 0.27 o.o1 Oe20 

BAO o.o1 

TOTAL 99.04 100.71 99.37 100.51 101.23 99.32 100.09 99.10 98.41 100.18 99.43 101!.33 

D E F 

I -1PC •lPE •2CC •2CE •3G I C•lG C•2MP I C•lCC C•lCE C•2PC C-2PE C•3PC p r c e g g p c e p r p 

SI02 51.50 53.30 51.80 56.40 c;".en 53.20 51.10 50.90 51.80 52.00 51.30 50.90 

AL203 :10e90 31.00 30.50 25.00 2A.40 28.90 30.60 31.60 30.80 30.30 ?9.AO 31.70 

FE203 0.74 1.06 0.82 0.913 1.02 o.96 1.15 0.64 Oe77 0.68 o.97 n.73 

CAO }4.30 13.30 13.70 10.30 1?.50 12.30 14.40 15.30 14.80 13.10 13.70 11).90 

NA20 3o45 4.09 3e46 5.61 4. 71 4.05 3.15 2.84 3e36 3.92 3.8'5 2. 71 K20 0.04 o.os o.06 0.49 o.2c; 0.29 o.ls 0.03 o.o9 0.09 0.13 o.os 

BAO 0.02 o.o1 

TOUL 100.93 102.83 100.34 98.80 l02.t=.8 99.70 100.58 101.31 101.63 100.09 99.75 l0le99 

F{cont'd) G 

C·3PE C•46 f C•1PC C•lPE C•2Cr. C•2C C•3MP C•4G I C•lPC C-lPE C•2PC C•?PE r g p r c e p g p r p r 

SIO?. 15 1o60 55.30 49.40 51.00 c;o.5o ss.oo 51.60 56.20 49,80 53.60 49.60 53.40 

AL203 29e70 27.30 3?.10 31.40 30.80 2K,20 29.80 27.70 31.70 29.70 :12.00 28.30 

FE203 Oe94 0,92 o.79 0.98 0.8?. 1.20 o.a1 1.06 Oe77 Oo86 o.so 0.97 

CAO l2o60 10.70 11';.00 15.30 l4.5n 11.30 13.20 11.00 15.70 12.90 15.50 10,90 

NA20 4e00 s,s8 ?.20 2.74 2.133 4,69 3,44 4.90 2.62 4.33 ?.50 4.70 

K20 Ool3 0,27 o.o6 o.o9 o.I::! 0,30 0.14 0.38 o.o1 o.zo o.o6 o.?.e 

BAO Oo01 o.o1 

TOTAL 98o97 100.07 100.55 101.51 qq.•q 100.69 99.05 101.?.4 100.66 101.59 100.47 9Ae5f. 

*'" 00 

tr.l 

> 

r::n 

t-3 

~ 

0 

t'"' 

0 

~ 

~ 

-<: 

0 

t""' 

C1 

> z 

!--; 

C1 

r::n 

tr.l 

:;:tl 

!--; 

trl 

r::n 
5102 

AL203 

FE203 

CAO 

NA20 

1<20 

BAO 

TOTAL 

SIO? 

AL203 

FE203 

CAO 

NA20 

K20 

BAO 

TOTAL 

SI02 

AL203 

FE203 

CAO 

to.A20 

1<20 

BAO 

TOTAL 

TABLE 6.-Chemical analyses of plagioclases from the Kalaupapa section-Continued 

I (cont'd~ 

C•3MP C•4G 

p g 

152o00 54,10 

28o90 27.90 

Oo73 0,97 

l2o00 11,00 

3o92 4,61 

Ool6 0,45 

97.71 99o03 

L(Cont'd) 

PCi?MP 

p 

52o50 

30o20 

Oo74 

l3o30 

3o67 

Oo18 

100.59 

PClPE r 

54o70 

25o40 

Oo84 

9o50 

5o96 

Oo99 

97.39 

PC .. JG 

g 

54,00 

28,60 

0,95 

12.50 

4,41 

0.27 

o.oJ 

100.76 

P(cont'd) 

PC2MP p 

52.10 

29.10 

0,86 

12,AO 

4.37 

0,22 

9Ch45 

J K 

I PC1PC PClPE PC2MP PC-3G I PClPC PC2CC PC2CE PC•3G I PC IMP PC1MP 

p r p g p c e g p r 

49o20 54,40 54.60 57.20 51.90 51.00 61.50 57.90 53.50 se.qo 3lo90 28,20 28,50 27.00 29.90 31.20 26ol0 26.20 29.40 27.fl0 

Oo73 O.A6 0,89 0,98 0,76 0,82 Oo69 Oo94 Oe82 o.A2 

15o90 12.40 12.10 10.70 13.90 14.30 7.60 9.50 12.50 9,50 

2o50 4,67 4.57 5,19 3o44 2.90 6o33 5.62 3.81 5.46 

Oo07 0,35 o.2q 0,53 Ool6 OolO Oo77 Oo72 Oe20 n.~2 

Oo02 o,ol o.02 o.oz Oo02 o.o1 o.oz o.o4 o.n1 

100.32 100.89 loo.q6 101.62 lOOoOE\ 100.32 103.06 100,90 100.27 102.81 

M N 0 P 

l PC1MP PC·2G ~- PClMP PC-2G J PC1CC PClCE PCZPC PC3MP PC•4G I PCJPC 

p g p g c e p p g p 

52.80 

29.90 

Oo77 

13.20 

3.65 

OolA 

Oo04 

100.<;4 

57.50 

27,30 

1.21 

10.60 

5,32 

0,43 

0,02 

102.38 

49,50 

29.90 

0.94 

13.40 

3.73 

o.21 

97.~8 

53.60 

28,00 

1,29 

10.70 

5.20 

0,32 

Oo02 

99.13 

51.50 

30.90 

Oo13 

14.10 

3.53 

Oo16 

100.92 

56.60 

28,10 

0,95 

10.20 

5.75 

0,41 

102.01 

51.50 

30.80 

o.eo 

13.60 

3o11 

0.15 

100.62 

52.80 

30.20 

Oo74 

13.30 

3o99 

Ool8 

Oo02 

101.23 

5A.70 

26.50 

0.78 

AoAO 

6o50 

0,60 

Oo02 

l0lo90 

Q R S 

so.no 

3l."i0 

o.An 

u.on 

3.'50 

0.12 

9q,92 

Pc•JG I PClPC PCIPF Pc~zc PC3MP PC-4G I PClMP PC•ZG I PclMP PC•?GI 

g p r c p g p g p g 

57.40 

25.30 

0.81 

Ao90 

6.52 

1. 01 

Oo06 

100,00 

48oAO 

31.90 

0,73 

16.50 

2.34 

0.11 

100.38 

56.00 

28,40 

0,91 

9,90 

5,7A 

0.38 

101.37 

51.80 

30.20 

0,87 

13.50 

3,89 

0,20 

100.46 

'':H,50 

30,30 

o,75 

13.00 

4o10 

o.zo 

99.85 

54.20 

28.90 

0,87 

11.20 

5.36 

0.30 

0,04 

lOOoA7 

54,10 

2Ao90 

0.83 

12.80 

4o54 

o.2e 

0.01 

101.46 

57,60 

25.90 

0,87 

8,40 

6o8l 

o.n~ 

o.o1 

100,31 

53.40 

2Ao40 

1.14 

11.5n 

4e74 

Oe34 

o.o~ 

99,55 

52.50 

28,00 

1.19 

12.30 

.. ,, 

0,42 

o.oJ 

qa,1n 

1-3 

> b:! 

~ rn 

~ 

I 

-J 

~ 

~ 
5102 

AL203 

FE203 

CAO 

NA20 

K20 

BAO 

TOTAL 

5102 

AL203 

FE203 

CAO 

NA20 

1(20 

BAO 

TOTAL. 

5102 

AL203 

fE203 

CAO 

NA20 

1<20 

BAO 

TOTAL 

TABLE 6.---Chemical analyses of plagioclases from the Kalaupapa section-Continued 

T U V 

I c-lPc c-IPE c-2MP c•3G ~-1Pc c·lPE c-2Pc c-ZPE c•lMP c•4G I c-1Pc r.•lPF. p r p g p r p r p g p r 

50e20 

33o10 

Oe70 

l5e20 

2o33 

Oo07 

101.60 

C•2PC 

p 

"i4o60 

29o80 

Oo72 

llo80 

4o54 

Oo26 

Oo02 

101.74 

54,10 

29,50 

0,84 

12.40 

4,07 

o.3o 

l0lo2l 

C•?PE 

r 

55.10 

27.70 

0,87 

10.70 

c;.o8 

0,55 

o.o1 

100.01 

X~cont'd) 

C•2MP C•3G 

p g 

59ol0 53.10 

26o20 27.50 

Oe5l 0,59 

6o80 11.30 

6o83 4,80 

Oe82 o.ss 

o.oa o.oz 

100.34 97,86 

I 

52.20 

31.90 

Oo76 

14.30 

3ol8 

0.12 

102.46 

V (cont'd) 

C3MPC 

p 

53.20 

29.70 

Oo65 

l2o00 

4o43 

Oo27 

o.oz 

100.?7 

C-1MP p 

53.90 

29o?O 

o.a, 

l?o20 

4o35 

o.3z 

Oo02 

l00,8t:; 

y 

54.80 

29.40 

1,10 

12.00 

4.44 

0,30 

o.o1 

102.05 

C3MPE 

r 

56.60 

?8.00 

0.62 

10.00 

5,73 

0,47 

0.14 

101.~6 

C•?.G g 

54.70 

29.60 

o.R7 

12.40 

4.47 

0.43 

o.ol 

102.48 

I 

52,00 

30,90 

0.61 

13.30 

3. u, 

0.23 

o.o? 

1oo.~~ 

C•4G g 

57,50 

2~.50 

0,84 

R,60 

6o2A 

0,94 

99.66 

C,.lMP 

p 

5~.70 

2Ao10 

0,60 

10.10 

s.s, 

0,41 

0,07 

100,c;4 

53,90 

28.60 

0,65 

11.60 

4,82 

0.38 

o.o1 

99,96 

so.lo 

31.70 

0.69 

14.70 

3.01 

Oo13 

100.33 

55.60 

29.50 

0,82 

10.50 

5.40 

0.33 

102,15 

w 

53.00 

29.60 

0.83 

12.00 

4.61 

0.29 

o.o1 

100.34 

58.90 

27.00 

0.69 

8.70 

6,34 

o,sq 

0.09 

102.31 

I c-1 PC c-1 PE c-2PC c-2PE c-4G 1 p r p r g 

52.90 

29.50 

0,63 

u.so 

4,33 

0,29 

0,01 

99.16 

z 

C•2MP p 

56,00 

28.50 

0,40 

10.10 

5,57 

o.so 

o.o4 

101.11 

'.)4,50 

28.40 

0,76 

7.60 

5.36 

o.39 

o.o1 

97.02 

C·3G I g 

57.80 

23.10 

0,84 

7.50 

6.97 

2.36 

o.o1 

98.64 

53.40 

28.00 

0.75 

11.60 

4.22 

0,28 

o.oz 

9R 0 27 

57.80 

27.80 

0.75 

9.50 

5.73 

0.46 

0.03 

102,07 

s7.oo 

21.oo 

Oo90 

e.eo 

6ol3 

Oo66 

o.o3 

100,52 

c;2.40 

29.40 

0.65 

11.90 

4,0f\ 

0.29 

0.03 

98.73 

ClMPC p 

~?..30 

29.70 

0,!;5 

11.70 

4,48 

Oo3l 

Oo04 

qq.oa 

X 

54.10 

28.70 

0,63 

9,AO 

5.17 

o.JA 

0.12 

98,90 

ClMPF. r 

56.60 

27.00 

0,54 

9.90 

6.74 

o.Az 

101.60 

01 

0 

l:_::l::j 

> 

~ 

~ 

0 

r 

0 

~ 

> 

~ 

<: 

0 

r 

0 

> z 

0 

rn 

l:_::l::j 

~ ~ 

trl 

rn 
AL203 

FEO 

MGO 

TI02 

CR203 

TOTAL 

Al203 

FEO 

MGO 

TI02 

CR203 

TOTAL 

AL203 

FEO 

MGO 

TI02 

CR203 

TOTAL 

AL203 

FEO 

MGO 

TIOZ 

CR203 

TOTAL 

TABLE 7.-Chemical analyses of opaque minerals from the Kalaupapa section 

[Localities A-Z are shown in fig. 3. Plotting symbols are p=microphenocryst, r=rim of phenocryst, e=edge of groundmass grain, i=inclusion in olivine, and g=groundmass grain] 

A B c D E 

I •lMPC •lMPE •2MPC •2MPE •3G •3G I •1MP •2MP •36 I •16 I •lG I L•l6 p r p r g g p p g g g g 

l4o30 2,67 13.40 2o45 1.90 0,40 2o68 4,36 lo32 o.s1 2.67 o.54 

4lol0 66.40 45o90 68.40 75.30 45.10 74.70 64.00 35.70 52.60 74.00 48.90 

6o80 3.62 c;.40 3.03 1.2q 2.49 3o90 4.85 4t38 lo77 0.70 5.45 

3o46 20.20 4o45 20.40 16.50 48.50 u.eo 8.60 55.60 45.70 20.30 43.00 

33o30 2.29 31.40 2o00 o.4o o.o4 7.35 22.00 0,03 o.o2 o.ol 0.28 

98.96 95.18 100.55 96.28 95.39 96.53 100.43 103.81 97.03 100.60 97.68 98.17 

E~cont'd2 F G 

L•2G L•2GE I T-lMP T•2I T-36r, L•36E I CTlMP CT1MP MT•2G MT•26 IL•2G IL•2G g e p i g e p p g g g g 

o.sJ o.aa 3.77 16.60 0.69 1.47 17.70 18.80 2.43 2.53 0.41 o.:n 

51o20 46.20 62.40 41.10 71.20 52.10 36.50 35.50 78.50 78.30 48o00 47.20 

5o 59 5,29 3o04 10.30 1.45 1.73 8.60 e,5o 1o02 0.95 lo98 2.01 

4lo00 39.20 l8o40 4.73 22.50 30,90 2.84 2.98 12.20 llo90 47.40 47.50 

Oo28 0,26 Ao60 27.70 o.o,r, 0.01 36.20 34.40 o.so o.o8 0.20 o.o3 

98.60 91.83 96.21 100.43 95.90 8b.21 101.84 100.18 94.65 93.76 97.99 97.07 

G (cont'd) I J 

CT•3I CT•3I CT ... 3I I T-lMP T•lMP T•1MP T•2MP T•2G T•2G I MT•lJ IL-11 MT-2G i i i p p r r g g i i g 

l4o60 15.00 7o90 4.55 2.Sq 2.04 1.25 1.82 1.44 10.oo 8,20 1.36 

45o30 44,40 42.40 sa.ao b3o70 60.00 63.50 11.20 70.90 69.30 43.20 70.70 

7e65 7.47 5.12 2.84 1.67 1.60 le39 1.09 0.96 4.67 6e60 1.33 

3o03 5.o7 22.60 15.40 22.00 23.10 25o90 22.00 23.10 11.40 37.20 22.90 

27oSO 27.70 17.20 17.!50 1.86 0.46 0.32 o.o3 o.os o.o3 o.u 

98.08 q9.64 95.22 99.09 9loR2 87.20 92.36 96.14 96e45 95.40 95.20 96.40 

K L M 

I JL-1G I CTl~P MTlMP MT-2G I CTlMP CTli>IP CTlMP CT2MP CT2MP MT-3G MT•3G tL•3G g p r g p p r p p g g g 

Oo20 15.90 2o33 1.62 12.40 12.60 6o60 11.70 11.60 1.99 o.st 0.30 

49o00 42.60 63o90 63.10 44.10 50.30 35.70 32.00 31.20 74.90 5?.40 37.00 

o.aq 6.10 2.23 2.17 a.9o 5.03 4o72 7.41 7.47 3.45 3.51 2.82 

48o90 4.23 2c;.oo 27.40 7.30 8,40 31.90 1.87 1.75 10.oo 35.90 48.40 

33.10 o.65 o.o4 22.50 23.70 14.20 48.70 51.90 O.lZ 0,03 

98.98 l0lo93 94.11 94.33 95.20 100.03 93.12 101.68 103.92 90.46 92.35 ee.52 

I 

t-3 

> ttl 

t""' 

t_::lj 

r:n 

,.... 

I 

-.".1 

Ol 

~ 
TABLE 7.-Chemical analyses of opaque minerals from the Kalaupapa section-Continued 

M {c ont' dL N 

RT-3G I CTlMP CTlMP MTl~P MTJMP CT2MP CT2MP MT2MP MT2MP MT-3G g p p r r p p r r g 

AL203 lo92 17,70 Hh30 5.23 5,!;1 16,60 16.60 3.18 3.69 1.~5 

FEO 5·29 3·1. 70 35.30 '50.30 !:13.40 40.10 41,30 62,10 59.60 64,40 

MGO 10.00 10.40 3,42 3,4"\ 8,60 7,92 3,96 4o00 2.05 

TIO?. ~8.70 4,04 4.05 23,00 21.41"1 4,36 4,31 22.40 23,50 21.70 

CR203 Oo06 29,20 3lo00 10.70 11,80 29,60 30,50 3,54 4o57 3.?0 

TOTAL 95.97 9~.64 99.0':) 92.65 915.56 99,26 100.63 95,18 95,36 93,:?0 

0 

I IL-3G MTIMP MTlMP ILlMP TL.lMP MT2MP MT2MP IL2MP tU~MP IL-3G 

g p p r r p p r r g 

AL203 o.Jq 3.70 ."3. 71 0,90 0,76 0.83 2.25 o.Ae 0.36 o. :n 

FEO 39o00 77,20 80,60 47.~0 28.00 70.70 78.00 39,70 35.00 39.10 

MGO 3o5Ft ?,86 2o77 1,54 o.s1 1. ?4 2.57 1.54 Oo67 1.87 

TI02 53o00 3,32 2.94 38,40 fi7.50 18,30 s.ao 49,90 58.90 !)3,80 

CR203 3,8R 4e31 1. 33 1,60 0.03 o.Ok o.o1 Oo03 

TOTAL 95,95 90,96 94.35 89,97 9A,J7 91.10 88.70 92,03 94,96 95,10 

P ~co n t' d) Q 

CT-11 IL2MP IL-3G I MTlMP ~TlMP MTlMP MTlMP MT2MP MT2MP CT3MP 

i p g p p r r p p p 

ALZ03 4ot!O o.;o 0,34 9,90 q,Jo 3.22 3.18 2,3f, 3,04 12.RO 

FEO 54ol0 46,80 4S,80 o:;s.oo SR,50 61,70 59,&0 62.00 61.20 41.30 

1'4GO Sol7 1,09 lo02 4.05 4oll 3.76 4o28 3.72 3o6l 9,}0 

TI02 18o30 4!i,20 4Ao00 12.70 14,30 23.00 27o30 23.30 24,80 ~.}A 

CR203 13-~0 13.?0 13.61"1 s.so 3.69 5,70 7.10 18.50 

TOTAL 95.67 96.39 95.16 94,85 99,~1 97.18 98,05 97,08 q9.75 89 0 Afl 

O~cont'dL R 

MT3MP MT4MP MT4MP MT4MP IL .. Sr. IL-5r. I MTlMP MTlMP ILlMP ILlMP 

r p p r g g p p r r 

AL203 4o79 7,60 A.1o 3,42 0,31 0.53 1.52 1.57 0.62 0,51 

FEO S7o50 55,20 62.90 62,fl0 44,40 46,10 76.30 A2,40 45.20 46,70 

MGO 4o9b 3,91 3oAA 3,32 3.14 3.31 o.12 0,()7 lo43 1.44 

TIO? ?lo60 14,30 1';,70 17.80 4q,sn 50,10 l4o20 11.60 48o60 48.F>O 

CR203 6o50 11.00 10.90 5,90 0.03 o.zo o.os o.o1 

TOTAL 95.35 92.01 10lo4A 93,1!4 97,(.7 100,07 Q2,94 9ft,29 95.85 97,?6 

MT-3G 

g 

2.86 

7"i.l0 

?,23 

13.20 

0.07 

93,46 

IL-313 I g 

(1,19 

30.10 

1,50 

5fl,90 

o.o1 

Rl:"lo70 

CT3MP p 

12.50 

5?,10 

7,81) 

A,f.O 

1A,40 

99o40 

JL-2G 

g 

0,30 

46.40 

2,56 

49,50 

98.76 

IL-3!'; J g 

0,4} 

40,:?0 

4.0F> 

153,00 

97.~7 

p 

cT-li i 

16.c;n 

zg.c;n 

11.10 

?.~6 

34.70 

94.61'1 

CT1"'P r 

S,AO 

3l,f.O 

4.7n 

14.90 

1l.AO 

6A,AO 

IL-?13 

g 

0,39 

47,nn 

;?,"iS 

50,40 

n.n1 

100.3'i 

I 

01 

!:....:> 

tJ:j 

> r:n 

t-3 

~ 

0 

~ 

0 

~ 

> -

< 0 

~ 

(') 

> z 

-(') 

r:n 

tJ:j 

~ 

-tJ:j 

r:n 
TABLE 1.-Chemical analyses of opaque minerals from the Kalaupapa section-Continued 

s T u 

I IL-lG I T•lMP UMPE T•3G T•3G L-4G I T-lMP T-lMP T-2MP T•3G g p r g g g p p p g 

AL203 Oo39 6.50 0.63 2,53 0,3Q 0,27 s.7o 4.2~ 4.oq 1.13 

fEO 38o30 57,00 49.80 8~.50 1'11.20 44.10 58.40 62,30 64,20 69,AO 

MGO 2ol7 3.08 3o33 lol8 2.79 3,99 4.76 4,75 3.87 1.32 

U02 56o.30 11,60 41o'50 4o39 29.60 49.30 14.30 16.00 19.70 25.no 

CR203 20.30 lo67 o.o7 0,02 0,02 s.2o 3.95 2.87 o.os TOTAL 97.16 9Ao48 96,93 93.67 94,00 97,68 91.36 91.28 94,73 97,30 

V (co nt'd) w X 

T•2MP T-16 T-3G I L-1G L-2G I T•1G L•2G I T-1MP 

L 

T-lMP T-2MP 

p g g g g g g p r p 

AL203 1o64 0.73 Oo42 0,?2 n.ZR 1,28 n.::12 19,90 lo24 17,50 

fEO fl4o50 71.40 "i4o30 43.20 40.80 #,8,40 47.30 27.10 56.70 31.10 

MGO 2o25 1.43 Oo60 o.aa 1,2c; 1.52 lo3l 13.30 3,59 10.60 

Tl02 23.70 19.30 36.20 so.so c;o.on 25.70 49.50 1.70 18.20 2,03 

CH203 3oU 0,07 0,04 0,04 Oo02 0,13 o.o1 38,90 ?,21 40.70 

TOTAL 95.22 9?.93 93.!:16 94,84 Cl2,35 97.0J 98.44 100,90 81.94 101,93 

Y (con t' d) Z 

T-3G I T-1 MP T-2MP T-3G l.-4G I g p p g g 

Al203 loOA 1,58 lo69 1.57 0,4? 

fEO 48o7U 69.10 69.00 70,1:i0 43,40 

MGO lo56 3,28 ?,87 2.76 3.41 

TI02 3lo40 22,50 22ofd) 21,40 49.80 

C'R203 Oo04 0,09 0.14 0,04 0,0?, 

TOTAL 82.78 91,.55 96.30 w,.21 Cl7oll 

v 

I T-1MP p 

?,62 

1r:;.ao 

1.25 

9,90 

3.37 

92.94 

L•2MP 

r 

3,3q 

4?.40 

~.24 

3'5.30 

4.96 

89,29 

T•l~P 

p 

2,5A 

53.10 

2.no 

34.00 

5.4n 

97o0A 

T-3G 

g 

1.31 

70.10 

1,03 

21.40 

o.os 

<n,aq 

t--3 

> t:1:j 

t-t 

tz:j 

00 

r 

-1 

01 

Cl.:)