Bulletin of the Geological Survey of Japam,vo1.41(11),p.619-626,1990 549.74 550.42 546.26/.21 552.3(81)
c鑓恥⑪齢翻⑪xyge晒s⑪瞼聖蓋艇⑪聯⑪s灘⑪囎
o置韻亘e e劉讃》⑪館裂苞es:蔭貿⑪㎜愈he J麗e町》董r麗醜9麗窺醜d
c漁舳◎亘㈱b⑪臨醜¢⑪即且exes,B欄盟
Toshiro MoRIKIYo*,Hideo HIRANo**and Yukihiro MATsuHIsA**
MoRIKIYo,T.,HIRANo,H.and MATsuHlsA,Y.(1990)Carbon and oxygen isotopic composi-
tion ofthe carbonatesfromtheJacupiranga and Catalao I carbonatite complexes,Brazi1.
B%」及G60Z.S%7∂.ノ4鎗α%,vo1.41(11),P.619-626.
Abs意聡e重:Carbon and oxygen isotope compositions were measured for carbonates from the
Jacupiranga and Catalao I carbonatite complexes in Brazi1.Theδ13Cvalues of the Jacupiranga
carbonates are uniform,ranging from-6.4to-5.6%with the average of-6.07%.Except for
one sample,theδ180values ofthe carbonates are between7.1and8.1%,and the averagevalue
is7.6%5.The isotopic compositions of the Jacupiranga carbonates represent the value of
primaryigneous carbonatite.Theδ13C values of dolomites are about O.5%higher thanthose of
calcites.
Theδ13C values of carbonates from the Catalao I complex range from-6.8to-5.2%
with the average of-5,83%.Those values are similar to the values of the Jacupiranga car-
bonates。However,oxygenisopotic compositions ofthe CatalaoI carbonatesshowawide range
of8.4to22.3%.Carbonateswiththelowestδ180values inthe complex are considered torepre-
sent the igneous stage.Carbonates with extremely highδ180values of about22%are con-
sidered to have precipitated from low-temperature hydrothermal fluids.The group of in-
termediateδ180valuesindicates avariable degree ofcontaminationbytheδ180-richhydrother-
mal carbonates.The contribution of secondary stage hydrothermal carbonates seems to be
significant in the Catalao I complex as compared with the Jacupiranga complex.The develop-
ment ofa network structure in the Catalao I complex mayhave enhanced the circulation ofthe
later stage hydrothermal fluids.
且.亙薦ro面et量樋
Carbonatite is intimately associated.with
anζaline rocks such as nephelinite and ijolite.In-
itia187Sr/86Sr values of carbonatite are low and
they are similar to those of alkali basalt.It is in-
ferre(1that carbonatite magma is(ierived from
the upper mantle.Carbon isotopic ratios of car-
bonatites togetherwith those ofkimberlites and
diamonds canbeutilizedto estimatetheisotopic
composition of deep-seate(1carbon.
Carbon an(i oxygen isotopic ratios of car-
bonatites have been reported by many resear一
*Department of Geology,Faculty of Science,
Shinshu University,Matsumoto390,Japan.**Mineral Resources Dept.,Geological Survey of
Japan.
chers (TAYLoR αα1.,1967;CoNwAY and
TAYLoR,1969;SuwA6彪Z.,1969;DEINEs,19701
DEINEs and GoLD,1973;SuwA6渉α風,1975).
TAYLoRααZ.(1967)postulatedthatprimaryig-
neous carbonatite has relatively limitedδ13C
andδ180ranges.且owever,there is a slight
isotopic difference between carbonatites from
different localities(DEINEs an(i GoLD,1973).
Stableisotopiccompositions oftheBrazilian car-
bononatites have scarcely been reported.This
.studyaimsatelucidatingthe carbon an(10xygen
isotopic features of the Jacupiranga and Catalao
I carbonatite complexes in Brazi1。
2. Geo且ogy⑪窟韻亘e J窺¢盟亙》置r我醜9ぎL我醜姐c我ta且ao
亙ea晦o盤戯eむ⑪聯且exes
鋤噸か㈱騨 Jacupiranga alkaline carbonatite complex is
一619一
ヒ
8%1擁塑働606・卿・冴JS%プ卿ヴノ4卿,%よ4ヱ,踊.Zヱ
10cated230km southwest of Sao Paulo and is
composed of peridotite, clinopyroxenite,
jacupirangite,ijolite,fenite,nepheline syenite
and carbonatite.It is oval shaped,.and65km2in
area.It intruded into the Precambrian mica
schist an(i quartz diorite in the Early Cretaceous
piriod(130±5Ma,AMARAL,1978).The car-
bonatites occur near the center of the complex
as two plugs,the northem and southem bodies。
The total exposure of the carbonatites is about
O.4km2.
According to Melcher(1966),the peridotitic
body was first emplace(1in the northem half of
the complex an(1then suπoun(ied by a ring intru-
sion of clinopyroxenite.After that,the circular
clinopyroxenite intnユde(1into the southern half
of the complex and differentiated into the cres-
cent-shaped ijolite body.Finally,carbonatite in-
tru(1ed as small Plugs into the central part of the
southern clinopyroxenite body (MELCHER,
19661GAsPER and WYLHE,1983al HIRANoαα1.,1990a).
HIRANo6!σ1.(1990a)have classified the car-
bonatites into four rock facies as follows:
Calcite carbonatite (CC),magnetite-rich
calcite carbonatite (CCmt),apatite-rich calcite
carbonatite(CCap)and dolomite carbonatite(DC).
Calcite carbonatite is the major facies of both
the northern an(1southern plugs.It consists
mainly of calcite,magnetite,apatite and
dolomite.Minor constituents are olivine,phlogopite, pyn’hotite, chalcopyTite an(i
valleriite.The amount of mafic minerals are
usually less than10%.JC-11and-46are from
this facies.Calcite carbonatite containing more
than 20% of modal magnetite is calledmagnetite-rich calcite carbonatite in this paper。
Apatite-rich calcite carbonatite consists of
medium-graine(i apatite and olivine with
calcite,phlogopite and magnetite.A small
amount ofdolomite is also contained.JC-18and
-26are from this facies.
Dolomite carbonatite occurs as small dykes in
both carbonatite plugs.It consists essentially of
dolomite with small amounts of apatite,
phlogopite,magnetite and sulfide mineralsJC-
27and-44are from this facies.The detailed
petrographic (iescriptions of each rock facies
are given in HIRANO ασ1.(1990a).The
Jacupiranga samples analyzed in this study are
listed in Table l and their localities are shown in
・Fig.1.
σ⑫戯伽01
CatalaoI carbonatite complexislocatedinthe
southeastem part of the Goias state,an(i it in-
truded into the Proterozoic metamorphic rocks.
The age of the intrusion is82.9±4.2Ma
(HAsuIand CoRDANI,1968).The complexhas a
circular shape an(1is about6km in(iiameter。
The rocks of the complex are as follows
(HIRANO6オα1.,1990b);
(1) Ultramafics and their metasomatized
rocks (ultramafics,phlogopite rock,meta-
phoscolite)1
(2) Phoscolite;
(3) Carbonatite and carbonate rocks
(dolomite carbonatite, magnesite-bearing
dolomite carbonatite,dolomitic sinter andothers).
Since the complex has been deeplyweathered,the relationship between these rock
types can onlybe observed in drill core samples.
The sequence of events leading to the forma-
tion of the various rock types is as follows
(HIRANoαα1.,1990b):
(1) Ultramaficrockswere crystallized from
a silicate magma.Some parts of the ultramafics
were serpentinized during the cooling of the in-
trusion.
(2) Carbonatitic magmas intruded into the
ultramaficrocks,formingthenetworkveinsanddykes of phoscolite and dolomite carbonatite.
Metaphoscolite was also formed locally along
the conduits.
(3) Crystallization of carbonate minerals
(dolomite and magnesite)from hydrothermal
fluids.Carbonate veinlets of the hydrothermaL
stage sporadically cut the early stage igneous
members(includingphoscoliteanddolomitecar-bonatite).
The Catalao I samples analyzed in this study
are listed in Table1.Alltheしsamples were taken
from a drill core,the site of which is shown in
Fig.2.CT-36,一38,一39A,一351and-352are the
rocks from stage(2)mentioned abo寸e.CT-40
and-41are representatives of stage (3),
一620一
Cα760%ごη¢40匿γ図召%乞εoホoφづo oo吻osづあo%げオhβαz7カo%σ孟召s (T.!レぞひグづ彦砂08!ごzZ。)
ぐ畏、砿、
\儲1く7
ヤ くてー~
旨》 %
o
Dolomiヒe carbona七ite
Calcite carbonatiヒe
Calcite carbonaヒitermagひeヒiヒ,e-rich
こ『acupirangiヒe(Clinopyroxenite)
Fauエヒ
Flow strUC七ure
Sample lodality
職o 200
勧D’
300m
Fig.1 Geological maか(H:IRANp象α砿,1990a)of㌻he Jacupiranga carbonatitεcomplex showing the
sample localities.
3.遍聯er置職蝋s
Carbon(iioxide was辱1iberated from carbonate
by the reaction with100%phosphoric acid at
25℃in..a vaCuum(McCREA,1950).二Calcite一、
dolomit“mi鴎uresw農re apalyzed uSing・中e dQu-
ble ext写actiQn technique dev“10pe(i by,EPsTEIN
4σ乙 (1964).,Carbon dio琴ide、obtaine4was
an琴1yzed Wit耳.a Varian,Mat25Q,mass spec-
tro卑eteratShipshuUniversi醇。For、oxygen,cor’
rectio坤.were享na(1gforisotopefr哉ctionationbet-
ween liberated carbon(1ioxide and original car・
b・nate。、Fraction琶tioロfact・rsdeterlninedby
Sharma and Clayto皐 (1965), (CO2-cc)
=1.01025and(CO2-do1)=1.01109,were used.
Theisotopic(lataarepresented intermsoftheδ
notationrelativetoPDBforcarbon,andSMOWfor q琴ygen。.丁与e、..堅perime墓tal grrors are
±0.1%f。rもoththe・3Cand・80・values.
A照1ytical results of the reference sar県ple
(Caρ03-1,.GSJ work:ing,standard)、弓re
presented in Tab1→2・.The measure舜va1双e5
agree well with the results by MoRlsHITA司nd
MATSuHISA(1984).
一621一
B%JJ4!勿z(ゾ’云h6G60旋)9づαzl S%γz7のア(ゾ’ノ4!)‘z%,Vbよ41』.〈砂.11
Table l Petrographic descriptions of the samples studied from the Jacupiranga and Catalao I carbonatite complexes,
Rock type Description
Jacup irangaJC-11
JC-18
JC-26
JC-27
Olivine-bearingcalcite carbonatlteOlivine-apatite-CalCite CarbOnatiteApatite-rich calc itecarbonatiteDolomite carbonatite,
JC-44 Dolomite carbonatite
JC-46 Calcite carbonatite
Catalao I CT-36
CT-38
CT-39A
CT-40
CT-41
Nb-bearing phoscolite(277m)
Dolomite(115m)
Dolomite(402。5m)
carbonatite
carbonatite
MagneSite-bearingdolomite carbonatite(415m)
Dolomitic(Cocarde)
sinter(246.4m)
CT-351 Metaphos co l ite (292m)
CT-352 Phoscol工te(292m)
76cc,14ap,8mt,101,1dol l mediumgrained, eaakly banded。3701+c l inohumite,32ap,21cc,4mt,4po,2dol l coarse grained・82cc,13dol,4ap,1mt l coarsegrained。69dol,27ap,2cc,2phl多 mediumgrained, weakly bande(L63dol.35ap,2mt: a very smallamOUnt Of interStit ialcalcite occurs.81cc,14dol,3mt,2sulfide l magnetlteand sulf ide concentration formsan irregular banding。
40phl,30mt,20ap,5dol,5pyc lmedium grained, do lomite occup iesthe interspaces of phl-mt-apaggregates.80dol,10norsethite,5py(finegrained),3ap,1phl,1pyc l coarsegrained.90do手,3mt,1phl l medium gralned,
banded.Magnetlteconcentrationformsabanding.Magnesite,dol l fine-grained,pos s ibly hydrothermal or工gin・
Abbreviations: cc-calcite, dol-dolomite,olivine, ap-apatite, po-pyrrhotite,pyc-pyrochlore. Numbers in (iescript ion are volume percentagesestimated petrographically。 The nomenclature of carbona’しitesafter Streckei sen (1980). Numbers in parenthes i s indicate thedepth of the dri l l core samp les (name of dri l lhole= 47E29N)・
Dol,other mineals (not deter-mined); aphanitic colloformtexture develops。80phl,clay mineral,ol(ser-pentinized)),10mt,10dol lmedium grained,80ap,6phi,5dol,4mt,3pyc lmedium grained。
mt-magnetite, Ol-
py-pyrite, phl-phlogopite,
■S
4。 A恥a亘y睦総且騰s戯ts躍雌姻is磯ss童o醜
Six carbonate samples from the Jacupiranga
complex and seven from the Catalao I complex
were isotopically analyzed.The results are
shown in Table2and Fig.3.
」㏄塑ε翼霧醐騨葛¢o聯亙εκ
The δ13C values of the Jacupiranga car-
bonates are in the range of-6.4to-5.6%with
the average of-6.07%(σn=0.29,n=9).The
carbon isotopic compositions are very uniform.
Except for one sample(JC-44calcite),theδ180
values of the carbonates are betweel17.1and
8.1%,and the average value is7.6%(σn=0.35,
n=8).JC-44calcite seems to be exceptional
an(1itsδ180value is2%6higher than the average
δ180value.
TAYLoR6渉α乙 (1967)postulated that theδ13C
一622一
Cごz7ゐo%ごz箆40髪yg6犯商o云¢珍o oo%z望)osづガo%(ゾ云hθoα760伊zごzセs (T.ノレ費)7づゑ砂06渉召Jl)
Fig.2
BRAZIL
く驚
一一
\
醗纒 Lateritederlvedfr。mthec。mplex
暫蹴繍laf:縢ed/鷲m認
☆ L・cality。fd湘h。1e(47E29N)
Reproduced fγ’om 凹ETAIS de Goi as
(Berbert,1984)
Surfacegeologicalmap ofthe Catalao I carbonatitecomplexshowingthesamplelqcality.In-
ner solid and dashed lines correspond to the outline of the complex.
一2
令ざ
㌔一4 2
0鐙 一6
の
一8
一10
‘‘Oka box7’
(Conway and Taylor,1969)
國・
Primary igneouscarbonatite
(Taylor et aL,1967)
血
血
議)JC
畠DOL CT
血
血
Fig.3
6 8 10 12 14 16δ180SMow(・ん。)
18 20 22
Plot ofδ180versusδ13Cfor carbonates from the Jacupiranga and Catalao I carbonatite com-
Plexes.
一623一
B距〃6ガ%(~ブ試h6θ召oJ{馨客αzJ・S%グz翌ヅ(~プノ4ρ召%,Vbよ41,・ノ〉1?.11
Table2 1sotopic composition of the carbonates from the
Jacupiranga(JC一)and Catalao I(CT一)car-
bonatite complexes.
Calcite Dolomite Calcite:dolomite
Sample 一 δ13C δ180 づ13C δき80 volume ratio
JC-11
JC-18
JC-26
JC-27
JC-44
JC-46
CT-36
CT-38
CT-39A
CT-40
CT-41
CT-351
CT-352
CaCO3-1
CaCO3-1*
一6.4
-6.4
-6,2
一5.8
-6.4
2。53
2.63
2.59
7.5
8.1
7.3 -5、8
-5.9
9.6 -6.1
7.7 -5.6
-5.3
-5.9
-5.2
-6.0
-6.8
-5.8
-5.6
一15.00**
一14.97**
一15.00**
CC>(iol
cc>do1
7・1 cc>4017.7 dof
7.3 do1》c6
8ユ cq>dφ1、.
13.2 do1
8.4 、do1
10.4㌧ .do1
22.3 、 dQl
21.7 doI
12.6 do1
10.4 do1
*MoRIsHITA and MATsuHlsA(1984)
**δ180values are given in the PDB scale.
values ofprimary igneous carbonatite are in.the
range of-8.O to-5.0%an(1theδ1曼0.Values.6.0冒
to8。5%。Theδ13C andδ180v41μes,〇五,t募e
Jacupirang4carb・nates章reremarkab1X旦nif・mandtheδi80valhes『afetheloΨesta血・n宮thercarbonatites from all over th6魚orld (e.ぎ.
DEINEs and GoLD,1973).It is noteworthy tha.t
the isotopic data from the Jacuplranga complex
are plotted ina smallar鈎withlntheprimaryig-
neous carbonatite field of TAYLO亘6如ゐ(1967).
They are also plotted near th6base of the“Oka
box” which was defined by CoNwAY and
TAYLoR(1969).The Jacupiranga carbonatites
occur as discordant igneous plugs in the
clinopyroxenite as described before.The car-
bonatites are of the deep-seate(1Plutonic type
and the total anlount of erosion to reach the pre-
sentlevelhasbeenestimatedtobeover1500m(M肌cHER,1966).It seems safe to say that
there has been no effect or alteration from sur-
faceweathering.Therefore,itis consideredthat
theisotopiccompositions oftheJa¢upirangacar-
bonates represent thevalue for primary igneous
carbonat藁“s in Sq4thgm B聡zi斗。,
Theδ180value of∫C-44calci亡e is ab6亡t2%6㌧
higher than that of the coexisting dolomite,
whereas theδ13C values are the same.The
amount of calcite in the rock:is very・small and
the calcites fill the grain boun(1aries of coarse-
grained dolomites.Judgingfromthe血ode ofoc-
currencq,the enrichmentofδ180inthecalcite is
interpreted as due to precipitaゼion from the
magmatic fluids of a later stagO probably at
lower temperature.
Theδ手3Cvalues ofdolomite,onthewhole,are
higher than those of calcite.The averageδ13C
value、o主dolomite is-5.9%,whereas that of
calcite(except fQr JC-44calcite)is-6.4%.The
tendencゾis commonly recognized in car-bonatite6(DEINEs,1970),but the(1ifferencebet-
weencalciteand dolomite observedinthis study
(0.員%on an average)is much smaller than the
rva
lue described’by DEINEs(1970).As for a
single rock:sample which・contains both calcite
and dolomite,一the do16雌te has higherδ13C
value than the coexisting calcite,except for JC-
44隻If we assume,that coexisting calcite and
do10mite are isotopically in equilibrium,we can
calculateisotopic.eOuilibr奪tiontemperaturesus-
ingSHEppARDand ScHwARcz’srequation(1970).
The results are as follows:
JC-26:」13Cd。1rcc=0.4 Tニ610℃.
JC-46:・」13Cdol-cc=畠0も8『・T=260℃.
The formervalue is consistent approximately
with equilibrium temperatures of595-570℃
estimated by GAsPAR and WYLLE(1983b)for
coexistingilmeniteandmagnetitefromthereac-
tion rock between jacupirangite and intruding
carbonatite of the complex.
磁伽伽1eo即伽 Theδ13C values of carbonates from the
Catalao I cdmplex range from二6.8to-5。2%
with the average of-5.80%(σ姦’=0.49,n=7).
Those values are almost th“Same as theδ13C
values ofthe Jac⑪iranga ca士bonatite.Theδ180
values。fthe}Catalab・lcarb・nates,h・wever,
show a condi(1αaぢ16range6f8.4to22.3%.
The oxygen isotope variation of the Catalao I
carbonates seems to correspond to their(1iverse
mode of occ亡rrencel Theδ13C andδ180values
ofthe CT-38dolomite,which exibits anigneous
textuてe塾are“1・$e㌻・.thec・mpgsiti・na1τange・f
the Jacupiranga carbonates.Therefore,it is
一624.一
C励o%卿鰐脚おo嬢・βo卿・3露加のhθo励・ηαホ63(T.砿07吻o伽及)
presumed that theCT-38domomite・representsaprimaryisotOpicSighature ofthe Catalao I car-
bo且atites. ” 一
The samples CT-40吐(magnesfteτbeaτing
dolomite caτbonatite)and CT-41(dblomitie
sint6r)occurasveipletsfilling’fissuresofthe
ultralnafics and are mai阜1y composed of cryp-
tocrys仁母11ine carbonate minerals.CTT41shows
a colloform texture.The、mode of occurrence
an(1textural characteristics suggest that they
have precipitated fr⑦m ・鮎10w-temperature
hydrothermal fluids‘(HIRANo.1αα1.,1990b).
The・δ士80 values of♂CT-40・and -41 are
remarkably high,while theδ13C values are not
di宜er¢ntfτ6m∴the・・ther$aゆ1es,fr6mthe
Catalao.rcρ出plex.From『the a資ove observa-
ti・n帥e卑aydeduc?th“f・11・winggeneticpr・一
cess fQr.these c母rbgnatltes。M6teoric water or
hydrothermal flui口which was enriched in180
permeated into the dolomite carbon&tite bodies,
and consequently,a part of the dolomite was
dissolved into the fluid.Afterthat,thecarbon in
carbon-bearing趾uid re-precipitated the secon-
dary ‘dolomite along conduits at lowtemperatures.The carbon i$otopic ratio of the
system was buffere(1in the predominatingprimafycarわ・nざtes』Thマs,veinsbf180-enrich-
ed cryptocrystalline dolorqit6,、wh6se δ13C’
values are almost identical to the primary
dolomite carbonatite,were formed.
The carbonates of CT-36,一39A,一351and-
352,whichhave intermediatevalues ofδ180,0c-F
cur interstitially and as“amygdu16s,,・in the』
phoscolite,and their amounts in the rocks are
sma11.They lie on a tie lie between the,prir叩ry
igneous carbonates and the hydrothermal car-
bonates in theδ13C vs.δ180diagram.The in-
crease in180is ascribe(i to a variable(1egree of
contaminationbythe180-richhydrothermalcar-
bonates.The contribution of secondary stage
hydrothermal carbonates seems・tO be signifi-
cant in the Catalao I complex as compared with
the Jacupiranga complex.The development of
network structure in the Catalao I complex may
have enhance(1the circulation of the later stage
hydrothermal fluids.
Ack齢w置e姻gem蝋s We wish to expressour gratitude to Prof.Y.KuRoDA of Shinshu
University for his critical reading of the
manuscriptl
’Re£ere玉【亙ees・
AMARAし,G。(1978) Pottasium-argon age st面ie忌
・血theJacupirangaalkaliゴedistrict,State
・fSa・Pa亘1・,’Brazi1.Pr・ceedings・fthe
first intβmational symposiu卑 on car-
bohatit6,p.297-302』DNPM,Brasilia.
BERBERT, C. 0. (1984) Cafbonati℃es an(i
associated mineral deposits in Brazi1。Gθo孟
S%7肌血卿,左砂ムn・.263,P.269二290.
CoNwAY,C.M.andTAYLoRIIH』P.Jr.(1969)018/
016 an(1 C13/C12 ratios of coe詫isting
minerals in the Oka and Magnet Cove car一
一bonatite bodies,ノb%名G診oZ.,vo1.77,P.618-
626.
DEINEs,P. (1970) The carbon and oxygen. isotopic composition of carbonates fro血▼
the Oka carbonatite complex,一Quebec,
Canada.σ800h吻』Co謝ooh吻.∠4吻,vo1.
34,p,1199-1225.
DEINEs,P.and GoLD,D.P.(1973)』The isotopic
composition’of carbonatite ahd-kimberlite
carboゴates and their b6aring on the
is・tΦicc・血噂ti・n’・fde?P』seatedcar-
b・血.06∂・h加.Cos〃zo・h枷.Aぬ,vo1.37,P.
1709-1733.
EpsTEINl S二l G良AF,D.L,and DEGENs,E.T.(1964)
0咳ygenl isotope stu(iies on the-o士igin of
dolomites。In CRへIG,H.,WAssERBuRG,G.
J。and MILLER,S。:L.eds,乃o孟o卿α嘱
oos%づo o勉吻づs吻。North-Holland,Amster一
・4a卑,P・169-180・
GAspER,」.C.and WYLLIE,P.」.(1983a) Magnetite in the carbonatites from the
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ブラジル国ジャクピランガとカタロン1カーボナタイト岩体の
炭酸塩鉱物の炭素・酸素同位体組成
森清寿郎・平野英雄・松久幸敬
要 旨
ブラジル南部の2つのカーボナタイト岩体,ジャクピランガとカタ・ン1のカルサイトとド・マ
イトの炭素・酸素同位体比を測定し,次の結果を得た.ジャクピランガの炭素と酸素の同位体比は
ともに一様で,平均値はδ13C=一6.07編,δ180=7.6%.これらは初生火成岩カーボナタイトの値
をしめす。カタ・ン1の炭素同位体比はほぼ一様で,平均値はδ13C=一5.83編である.酸素同位体
比は,試粁の産状のちがいにタり,大きな変動幅をしめすが,それは火成活動後の熱水作用に起因・
するとして説明できる.
(受付=1990年3月27日0受理:1990年9月1日)
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