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島根大学地球資源環境学研究報告 17，57～67ページ（1998年12月）
Geoscience Rept．Shimane Univ．，17，p．57～67（1998）
Major and trace element analyses ofCretaceous to Miocene
sedimentary rocks from the Shimanto terrane，Kii Peninsula， SW Japan
Bany Roser＊，Hiroaki Ishiga＊＊，Takanori Bessho＊＊＊and Kaori Dozen＊＊＊＊
Abstract
The Cretaceous－Miocene Shimanto temne of southem Japan is we11一㎞own geologically，but comparatively
few geochemical studies have been made and comprehensive whole－rock data are scarce．This report contains
whole－rock XRF analyses of100sandstones and mudstones spanning the stratigraphic range of the Shimanto se－
quence in Kii Peninsula，Wakayama Prefecture．Data include m勾or elements and19trace elements（As，Ba，Ce，
Cr，Cu，Ga，La，Nb，Ni，Pb，Rb，Sc，Sr，Th，U，V，Y，Zn and Zr）．Seven analyses of post－Shimanto sediments
（Tanabe andKumano Groups）are also included．Inte甲retation ofthe datain tems ofprovenance and evolution
of the terrane will be published elsewhere．
key words：Shimanto terrane，geochemistry，Cretaceous，Paleogene
lntroduction
The Cretaceous－Miocene Shimanto terrane of south－
em Japan is one of the world’s best㎞own accretion－
ary prisms，comprising a voluminous sequence of
trench－fill and forearc basin－fill sediments deposited at
the Japan Pacific margin（Kimura 1997）．Outcrop
length is some1400㎞，extending丘om the Kanto
Mountains near Tokyo southwest to the Nansei Is－
1ands．Numerous studies have examined many aspects
of the Shimanto，including general geology，paleonto1－
ogy， petrography， heavy 血nerals， tectonics， dating，
and evolution（Kumon1983；Kumon et a1．1988；Taira
et a1．1988；Ogawa et a1．1988；Agar et a1．1989；
Teraoka and Okumara1992；Yanase1992；Kimura et
a1．1996；Bessho1997；Ohmuri et a1．1997；and many
others）．Geoche血cal studies have，however，been rela－
tively few，and have generally been based on limited
data sets or have been part of larger studies （e．9．Ka－
shima1992；Kumon and Ki血na血1994）．Geoche面一
cal studies of sedimentary te皿anes have become
increasingly common in recent years，and a number of
che血cal discriminants and indices now pem血t evalu－
ation of provenance， tectonic setting， weathering
＊ Dept．of Earth and Planetary Science，Graduate School of Science，
Hokkaido University，Sapporo O60－0810，Japan
＊＊@Dept of Geoscience，Shimane University，Matsue690－8504，Japan＊＊＊@Yao－Higashi High School，Yao，Osaka581－0885，Japan
＊＊＊＊Dept．of Geosciences，Osaka City University，Sugimoto 3－3－138，
Sumiyoshi－ku Osaka558－8585，Japan
histoly，terraneevolutionandtectonostratigraphicrela－
tionships（e．g．Nesbitt and Young 1982；Roser and
Korsch1986；McLennan et a1．1993；Kumon andKユnlinanli1994；and others）．
The Shimanto sequence in Kii Peninsula，southeast
of Osaka，has been mapped and studied in detai1，and
a we11－established stratigraphy exists（Suzuki et a1．
1979；Tateishi et a1．1979；Tokuoka et a1．1981，1982；
Kumon et a1．1988）．Detailed petrographic analysis has
also been canied out in this area（Kumon1983）．This
prior work provides an ideal ffamework for geochemi－
cal studies．
This report contains comprehensive whole－rock XRF
analyses of suites of sandstones and mudstones span－
ning most of the Shimanto sequence in Kii Peninsula．
The intention here is simply to report the data；inter－
pretation will be published elsewhere（Roser，in prep．）．
The sample suites were collected with the aim of test－
ing stratigraphic geochenlical variation and evolution
in the Shimanto temne，using the extensive geologica1
㎞owledge of the area as a base．The data contained
here constitute a reference set for future comparison
with other Shimanto sequences，and with other large
accretionary terranes elsewhere．
Geological Outline
The study area lies south and east ofWakayama city
（Fig．1）．The general geology of the Kli sequence has
been well described by a number of authors（e．g．
57
58 Bany Roser，Hiroaki Ishiga，Takanori Bessho and Kaori Dozen
Suzuki et al．1979；Tateishi et al．1979；Tokuoka et a1．
1981，1982；Kumon1983；Kumon et a1．1988）．The
following su㎜a埋ofthe geology is drawn mainly
from the culmination of that work（Kumon et a1．1988）
and field observation．
The Shimanto temne is separated ffom the Chichibu
terrane to the north by the Butsuzo Tectonic line，but
is itself intemally divided into three sub－belts（Hida－
kagawa，Otonashigawa，and Muro）ftom north to south
（Fig．1）．These belts are named ffom the stratigraphic
groups which occur within them．A schematic strat－
igraphic sequence is given in Fig．2．
五1i4αんα8αwαG70砂
The Cretaceous Hidakagawa Group consists of the
Hanazono，Yukawa，Terasoma，Miyama，Rytりin and
Nyunokawa fomations，from no貰h to south．The Ha一
nazono Fomation（Coniacian－Campanian）1ies in the
north of the Kii Peninsula，and consists primarily of
shale，with sandstone，greenstone and chert．It is sepa－
rated丘om the other Hidakagawa fomations by the
Tst功ido Tectonic Line，and was not sampled in this
study．Yukawa Formation（Hauterivian－Turonian）oc－
curs in central Kii Peninsula，and consists of thick－
bedded sandstone，sandstone－shale altemations，and
shale；metabasalts are lacking．Terasoma Fomation
（middle Turonian－Santonian）crops out in the north－
west of the Hidakagawa Group，against the Butsuzo
Tectonic Line and a両oining Miyama Fomation（Fig．
1）．Sequences consist of well indurated sandstone－shale
altemations．Varying sandstone－shale proportions have
enabled division into three members．Miyama Foma－
tion （Coniacian－Santonian） outcrops in a continuous
belt west ffom its inland contact with the Yukawa For一
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Fig．1 Simplified geological map of the Shimanto temne in Kii Pennsula，and sample sites．Based on Tokuoka
et al． （1981），Kumon et a1．（1988）and Bessho（1997）．Fomlation abbreviations：Hidakagawa Group：Yu－
Yukawa；TE－Terasoma；Mi－Miyama；Ry－Ryujin；Ny－Nyunokawa．Otonashigawa Group：U－Uridani；Ha－
Haroku．Muro Group：Northem Belt Ya－Yasukawa；Uc－Uchikoshil Ko－Kogawa；Southem Belt Wa－Wabuka；
Mit－Mitogawa；S－Shimotsuyu．
M勾or and trace element analyses ofCretaceous to Miocene sedimentary rocks from the Shimanto temne，
Kii Peninsula，SW Japan
Post－ShimantoUη0㎝’om砂
Tanabe
7Sω11DOTEO70ハ〃0 」L〃Vε
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59
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Mitogawa
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HOIVGし，
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GOθ0十個G，’7EO70A〃O L〃V」E
Hidakagawa Group
NTH F
Muro，Group l
：‘
ロ ’協4TS切V』∋
H，月L4，
E4しIL7一
SHIMANTO TERRANE Kii Peninsula
Based on Kumon（1983），Kumon et al．
（1988），＆Kimura（1997）
Fig．2 Schematic stratigraphy of the Shimanto temne in Kii Peninsula．
mation（Fig．1）．Both“flysch”（sandstone－shale alter－
nations）and chert－greenstone facies occur．The latter
are inte甲reted as olistostromes（Kumon et a1．1988）．
Sampling for this study was confined to coherent se－
quences．The Ryujin Fomation （Campanian－Maasthchtian）also outcrops in a continuous belt，and
near the coast is temゴnated by the Gobo－Hagi Tect－
onic Line（Fig．1）．Facies association differs from the
above units，being dominated by black shale，with
lesser and thin shale－sandstone altemations，along with
greenstones and stratified acidic tuffs．Nyunokawa For－
mation （Campanian－Maastrichtian）outcrops inland，
south of the Ryゆn Formation，and is also teminated
to the south by the Gobo－Hagi Tectonic Line．Nyuno－
kawa sequences are primarily medium to very coarse
grained sandstone－shale“flysch”altemations，but con－
glomerates and sporadic greenstones also occur．Clasts
in the conglomerates include sedimentary rocks，felsic
volcanics and granitoids．
0∫onαshゴ8αwαGro叩
The Otonashigawa Group foms a relatively na置ow
east－west trending belt，bounded by the Gobo－Hagi
Tectonic Line to the north and the Hongu Fault to the
south．Age control is less certain due to paucity of re－
1iable fossils，but is presumed to be Paleocene to early
60 Bany Roser，Hiroaki Ishiga，Takanori Bessho and Kaori Dozen
Eocene based on the relationships with the Hidaka－
gawa and Muro Groups（Kumon et a1．1988）．The Oto－
nashigawa Group is cut into a mmber of imbricate
slices by north－dipPing reverse faults，and also displays
several orders of folds．The sediments consist of mud－
stone，and sandstone－shale and sandstone－conglomerate
altemations．
The sequence is divided into the Uridani，Haroku
and Fudono fomations in ascending order．The Uh－
daniFomationoccupiesthecentralpo質ionofthebelt，
and consists of monotonous black bedded mudstone，
commonly containing calcareous nodules．Red and
green mudstone also occur toward the top of the se－
quence，but greenstones and chert are absent．Haroku
Fomation foms the m司odty of the belt，compdsing
sandstone－shale altemations which become thicker and
coarser upwards．Lower sandstones are frequently
graded and laminated．Trace fossil suggest relatively
deep water deposition．In the upper part sandy units
are typica1，and very coarse sand and polymict con－
glomerate horizons occur in some areas．Fudono For－
mation consists of muddy altemations of sandstone
and mudstone，and crops out in a very restricted area．
It was not sampled in this study．
〃配ro G70砂
Muro Group sediments occupy an extensive area
southeast of the Hongu Fault（Fig．1），and range in age
from Eocene to Early Miocene．The Muro Group is
composed of sandstone，mudstone，sandstone－mudstone
altemations，and conglomerate．Compared with the Hi－
dakagawa and Muro Groups，sandstones are more
quartzose and feldspathic （arkose and feldspathic
arenite）and are thus less lithic．Induration is also less
marked．Conglomerate clasts （pebble－cobble） are
mainly sandstone，chert and felsic volcanics，with
lesser granitoid，shale and limestone clasts．
The Muro sub－belt is divided into two by the
Matsune－Hirai fault（Fig．1），delimiting northem and
southem blocks．Deformation is less than in the other
groups，with folding fom血g anticlines and synclinori－
ums（see Fig．80f Kumon et a1．1998），particularly in
the northem belt．In the southem belt block faulting is
more typica1．Both blocks are divided into three con－
fomable and co∬elative fomations：the Yasukawa，
Uchikoshi，and Kogawa（north）and the Wabuka，Mi－
togawa and Shimotsuyu（south）．Yasukawa Fomation
consists mainly of sandstone and bedded mudstone，
and coarsens upwards in its upPer part Correlative
Wabuka Fomation in the southem block consists of
mudstone and muddy sandstone altemations．The
Uchikoshi and Mitogawa fo㎜ations are characterised
by sand－do血nated sequences，although both muddy
and polymict conglomerate horizons also occur．The
Kogawa and Shimotsuyu Fo㎜ations exhibit a wide
variety of lithofacies，ranging from sand－dominated，
sand－mud altemations，mud－dominated，and conglom－
eratic beds．Both fonnations have been divided into a
mmber of units based on variations in their facies as－
SOClatlons．
Pos∫一Shin¢αn∫o S84∫nz6n∫s
The Muro Group is unconfo㎜ably overlain by fore－
arc sediments of the Miocene Tanabe and Kumano
Groups．Both exhibit relatively simple stm．cture，and
varied lithofacies ranging ffom conglomerates to coal
and shale deposits，with depositional environments
ranging ffom bathyal to shoreline facies（Ch麺iwa
1988；Hisatomi1988）．
Sample Suites
The Shimanto suite comprises100samples．Most
are fine to medium grained sandstones，since the focus
of the collection was comparison with published modal
data．Some coarse sands，very fine sands and mud－
stones were also collected to test grain size variations．
Samples were usually collected at bed midpoints to
avoid rip－up clasts where present，and basal heavy
mineral concentrations if present．
The Hidakagawa Group is represented by49samples．
Miyama samples（MI1－7）are very fine to medium
sands，generally fヤom massive beds．One mudstone
（MI5）was collected．A larger suite of samples ranging
丘om medium sand to mudstone was collected ffom the
Terasoma Fm．（TE1－15）．These were split between
the lower（TE12－15），middle（TE1－7）and upper units
（TE8－11）．Beds sampled ranged ffom10cm altema－
tions of sand and mud（TE13，14）through lO－50cm
bedded Tb－Te turbidites with sand：mud ratio of＞15：1
（TE1，2），to massive amalgamated sands4－5m thick
（TE15）．Finer grain size of the Ryujin Fm．re－
stricted sampling to four mudstones and three sand－
stones （RY1－7）．The sands were collected 丘om
isolated，thin（＜30cm），very fine sandstones in mud－
dominated sequences．Nyunokawa Fm．（NY1－9）sam一
M勾or and trace element analyses ofCretaceous to Miocene sedimentary rocks ffom the Shimanto temne，
61 Kii Peninsula，SW Japan
ples range ffom mud to fine sand，collected ffom tervals；only one mudstone was collected．Sandstones
P・・rly－graded10－50cmbeddedsandst・ne－shalealter－sh・wdistinctplanelaminati・n（MT3），andgrading
nati・ns・whichweregenerallysand－d・minated・ 丘・mc・arsesand，withmudhp－upclastsatbedbases
（MT4，6）．Shimotsuyu Fm．samples（SM1－6）consist
The majority of fifteen Otonashigawa Group sam－ of plane－or convolute－1aminated very fine sandstones
ples were collected ffom the Haroku Fm．，spanning the ffom a single locality between Yokoshima and
grain size range from coarse sand to mud．Both upper Soshima．
（OT5．7，11．12）and lower（OT3，4，8．10）Haroku
members as mapped by Suzuki et a1．（1979）and
Tokuoka et a1．（1981）are represented，collected along
an inland road traverse north of Kurisagawa．Beds var－
ied widely in thic㎞ess（10－200cm）．Most were not
strongly graded，and mud was subordinate．Three sam－
ples（TOK1－3）fヤom coastal exposure at Kirimi－zaki
were collected ffom thick（1－3m）sandstones，which
were strongly graded ffom granule to fine sand．Uri－
dani Fm．（OT1，2）mudstones were taken fヤom a
bedded mudstone exposure near Kurisugawa．This
contained scattered carbonate concretions．The Fudono
Formation was not sampled．
Thirty six samples represent the Muro Group，with
18ffom both the northem and southem belts．Samples
were collected丘om equivalent fomations in both
blocks．Northem block fomlations（Yasukawa，Uchiko－
shi，and Kogawa）were sampled inland（Kurisagawa
district）as coastal exposures of northem belt Muro
sediments are limited by overlying Tanabe Group sedi－
ments．Only three samples were collected from the
Yasukawa Fm．（YA1－3）．These comprise massive
fine to medium sands ffom bedded sandstone units，
1acking mudstone．Six samples fヤom the Uchikoshi
Fm． （UC1－6）range fヤom coarse sand to mud，taken
from thickly bedded and often graded sandstone units
with subordinate mud．Mud hp－ups were common in
several samples（UC1，2）．Kogawa sandstones（KO1－
9）were collected ffom four localities．Beds sampled
ranged from thin－bedded units（10－20cm）showing
marked plane lamination and weak convolution（KO1，
2）to thicker（30－60cm），more massive units（KO8，9）．
Southem block equivalents（Wabuka，Mitogawa，
Shimotsuyu）were collected ffom coastal exposures．
Wabuka Fm．（WB1－6）samples are massive（WB1）
or plane laminated（WB2）fine－medium sandstones
from thickly bedded（20－100cm）coherent sandstone
facies．Mitogawa Fm．（MT1－8）was collected at three
sites between Susami and Esu－zaki．Most are very fine
to medium sandstones ffom thick sand－dominated in一
Seven samples were also collected ffom single expo－
sures of the post－Shimanto Tanabe and Kumano
Groups．Time did not pemit more extensive sampling，
andthesuitecannotberegardedasfullyrepresentative
of Tanabe／Kumano compositions．Additional sampling
is required．The existing Tanabe samples（TN14）are
very fine－grained laminated sandstones，ffom5－10cm
sandstone－shale altemations in the Hiki Fomation
（Lower Tanabe Grp）at the west end of Hiki Beach．
Kumano Group samples（KM1－3）are buff－weathering
coarse silts ffom dcm－bedded coastal outcrop of Shi－
mosato Fomation（10wemost Kumano G甲）east of
Tanosaki．
Analytical Methods
Samples were coarsely chipped（＜1cm diameter）in
a mamal hydraulic rock splitter，removing any su㎡i－
cial weathering or oxide staining．Any chips containing
visible mud rip－ups clasts or significant veining were
also discarded．The ffesh chip was nnsed repeatedly in
tap water，followed by distilled water，and steeped
ovemight in deionised distilled water．Oven－dried sam－
ple chip was then cmshed for30－60seconds in a
tungsten－carbide ring mi11，with sample weights rang－
ing from70g in the shales to a maximum of200g in
the sandstones．Sample weights exceeding70g were
cmshed in several loads，which were then combined．
Previous work has shown that conta血nation from this
cmshing equipment is not detectable for all the ele－
ments reported here（Roser et a1．，1998）．Mill times are
adequate for rocks of the degree of induration shown
by the Shimanto samples，producing powders with a
median grain size of＜5microns（Roser et a1．，1998）．
Major element analyses were made by XRF，using
the Rigaku RIX－2000instrument at Shimane Univer－
sity，which is equipped with an Rh－anode X－ray tube．
Analyses were canied out on an anhydrous basis，us－
ing the ignited material ffom loss on ignition（LOI）
determinations．LOI was measured by weight loss in
5－6g of oven dried（110℃）sample after ignition at
62 Bany Roser，Hiroaki Ishiga，Takanori Bessho and Kaori Dozen
1000℃in a muffle fhmace for two hours．Major ele－
ment detemnnations were made on fused glass beads
prepared with commercial lithium tetraborate flux
（Merck Spectromelt⑧A10）in an NT－2000automatic
bead sampler，with preheat，fusion and agitation times
of120，120and180seconds，respectively．Sampleweight used was O．7000g，with3．5000g of且ux，giv－
ing a1：5sample：flux ratio．The method is essentially
that of Nonish and Hutton（1969）．Calibration was
made using standard reference samples produced by
the Geological Survey of Japan，and analyses moni－
tored by repeat analyses of GSJ standards JB－1a and
JG．1a．Additional detail of the analytical methods will
be provided elsewhere（Sawada et a1．，in prep）．
Table l XRF trace element analysis instmment condi－
tions，sensitivity and lower limits of detection．
Element／ Peak Line Tube kV／mA XstI DET COL time
c／sec LLD
m（m）
Trace elements were analysed by the Analytical Fa－
cility，VictoriaUniversity ofWellington，New Zealand，
using a Philips PW1404automated sequential XRF
spectrometer．Techniques were si血1ar to those de－
scribed in more detail by Palmer（1990）and Roser et
a1．（1995），ffom which the following outline is sum－
marised．All elements were detemined on boric acid－
backed pressed powder pellets（Nonish and Hutton
1969）40㎜indiameter，containing4gofundilutedhydrous sample．No binder was used．The trace ele－
ments were detemined in two blocks（Sc，V，Cr，Ni，
Cu，Zn，Zr，Nb，Ba，La，Ce and Ga，As，Rb，Sr，Y，Pb，
Th，U）using Au and dual anode Sc∠Mo x－ray tubes，
respectively．Su㎜卸nstmmentconditions，sensitivi－
ties，and lower limits of detection（LLD）are given in
Table1．The sensitivities and lower li血ts of detection
are calculated for an average andesitic matrix（USGS
standard AGV－1）．The instmment was calibrated using
a wide range of intemational rocks standards（GSJ，
USGS，ANRT，and SARM）．A number of synthetic
trace element and matrix pellets were also included to
allow accurate detem血nation of line overlaps and
absorption edge corrections．Regression lines were ca1－
culated using the Philips regression mode1，and the in－
temal ratio method using MoKαand AuLαCompton
peaks was used for matrix co皿ection．For elements
with wavelengths longer than the Fe absorption edge，
empincallydeteminedalphafactorswerecalculatedtocorrect for Fe，Mn，Cr and Ti absorption edge effects
where necessary．
As Kα Sc／Mo 80／30Ba Lβ Au 60！40
Ce Lβ Au 60／40
Cr Kα Au 60／40
Cu Kα Au 60μO
Ga Kα Sc！Mo 80130La Lα Au 60140
Nb Kα Au 80130
Ni Kα Au 60140
Pb Lβ Sc／Mo 80／30
Rb Kα Sc／Mo 80／30Sc Kα Au 60／40
Sr Kα Sc／Mo 80／30
Th Lα Sc／Mo 80130
U Lα Sc／Mo 80130V Kα Au 60！40
Y Kα Sc／Mo 80！30
Zn Kα Au 60／40
Zr Kα Au 80130
200 SC F 80
220 FL C 160
200FLF160200 FL F 80
200 SC C 80
200 SC F 60
220 FL C 100
220 SC F 80
200 SC C 80
200 SC F 100
220 SC F 100
200FLF 80200 SC F 80
200 SC F 150
220 SC F 200
220 FL F 80
200 SC F 40
200 SC C 40
220 SC F 80
5475903092920920674
8104732724615532296
1 1 2 1 2」1
6327455789167239078
2373442124565113651
0330012101010111001
Results
Results for m句or and trace elements are listed in
Table2，by fomation．The data are listed on a hy一
DET（Detector）：SC＝scintiilation，FL＝刊ow counter
COL（co”imator）：F＝fine；C＝coarse
Peak Time（sec）；total background time is equaI
C／sec／ppm－sensitivity；LLD－Iower”mit of detection
drous basis．Lithology was estimated ffom hand speci－
mens using a hand lens and grain size comparator．
Where trace elements were below the lower li血t of
detection，they are listed as＜ （n），where n is the
rounded LLD ffom Table1．The data provide a useful
reference set，intended as a benchmark in fUture stud－
ies of other Shimanto sequences．
Acknowledgements
This work was supported by grants－in－aid O8640571
（B．P．Roser）and O7304040（F．Kumon）ffom the Japa．
nese Ministry of Education，Culture and Science．
Takao Tokuoka and Takahiko Sakamoto helped with
logistics and field work respectively． Yoshihiro
Sawada chee㎡ully provided ffee access to the Shimane
University XRF facilities，and help during the m勾or
element analysis．John Patterson and Ding Reng car－
ried out the trace element analyses at Victoria Univer－
sity．Our thanks to all the above for their assistance．
R、eferences
Agar，SM．，Cliff，RA，Duddy，1．R．and Rex，D。C．
1989．Accretion and uplift in the Shimanto Belt，SW
Japan． Jo麗rnα1 ρプ∫h6 Gεolo8∫cαl Soc’ε乏y， 、乙on40n
146，893－896．
Bessho，T．1997．Heavy血neral composition of the
Upper Cretaceous sandstones in the Shimanto Belt
of the centra1－westem Kii Peninsula，Southwest Ja一
Table2 Major element and trace element analyses of Shimanto terrane sedimentary rocks，Kii Peninsula．Major elements wt．％，
LITH＝lithology（CS＝coarse sandstone；M＝medium sst；FS＝fine sst；VFSニvery fine sst；SLT＝siltstone；MUD＝mudstone／shale）．
SA孝 LlTH
trace elements p．P．m．LOIニ10ss on ignition．
SiO2 TiO2AI203Fe203 MnO M O CaO Na20 K20 P205 LOI SUM As Ba Ce Cr Cu Ga La Nb Ni Pb Rb Sc Sr Th U V Y Zn Zr
HIDAKAGAWA GROUPYukawa
じ ご
椚胞W鴨椚門門椚門門
SSSSSSSSSS
MMCFCMFMMC
Miyama
12345678
MMMMMMMM
MSFSFSVFSMUDFSMSVFS
TerasomaTElTE2TE3TE4TE5TE6TE7TE8TE9TE10TEl l
TE12TE13TE14TE15
VFSFSMSMSVFSFSMSFSMUDFSFSFSFSMUDVFS
RyUIIn
酒戦鴨桝悔紛W
RRRRRRR
MUDVFSMUDMUDMUDVFSVFS
66．39
67．27
70．25
70．87
72．30
72．08
70．80
69．62
71．76
68．97
75．72
76．49
76．30
73．80
70．68
73．38
75．04
74．40
73．04
72．98
72．46
75．05
72．29
76．36
68．63
75．44
64．49
76．02
74．56
73．76
73．64
66．41
72．40
65．08
72．45
70．60
68．11
64．45
74．31
69。79
0．48 14．76
0．47 14．24
0．36 13．50
0．35 11．93
0．33 12．72
0．32 12．62
0．41 12．55
0．37 13．00
0．29 12．48
0．41 10．96
0．32 11．95
0，31 11．94
0．32 12．14
0．38 13．01
0．51 14．56
0．45 12．52
0．29 11．84
0．38 13．67
0．30 13、75
0．41 13．27
0．33 13．80
0．30 12．80
0．45 13．20
0．36 11．60
0．56 13，33
0，34 12，87
0．62 16．43
0．29 10．82
0．32 11．29
0．38 13．23
0．62 12．27
0．57 15．45
0．45 13．85
0．65
0．46
0．57
0．61
0．71
0．26
0．54
16．32
13．68
13，86
15．64
17．47
12．25
14．54
4．14
4．22
3．06
2．10
2．77
2．49
3．35
2．23
2．44
2．97
2．52
1．90
2．17
2．76
3．87
3．29
2．41
2．45
2．35
3．11
3．56
2．43
3．98
2．38
5．45
2．42
4．63
2．41
2．62
3．03
3．15
5．57
3．14
5．74
3．74
4．80
4．71
5．50
1．97
3．82
0．05
0．09
0．06
0．06
0．04
0．04
0．05
0．05
0．07
0．16
0．05
0．03
0．03
0．04
0．05
0．05
0．04
0．02
0．05
0．06
0．06
0．05
0．06
0．06
0．07
0．02
0．02
0．04
0．05
0．05
0．05
0，09
0．07
0．07
0．04
0．09
0．05
0．06
0．06
0．05
1．91
1．62
1．32
0．86
1．10
1．02
1．20
1．03
0．52
1．26
0．74
0．51
0．65
0．79
1．06
1．00
0．61
0．71
0．79
0．91
0．68
0．59
1．58
0．90
2．09
0．73
1．27
0．63
0．64
1．07
1．11
1．85
1．26
1．73
1．07
1．40
1．41
1．64
0．29
1．03
1．97
2．18
2．11
4．01
1．87
2．45
0．67
3，37
2．68
5．69
0．44
0．74
0．72
1．06
0．65
0．97
1．03
0．30
1．31
0．96
0．78
0．49
1．30
0，90
0．90
0．47
0．51
1．91
2．21
0．71
1．37
0．68
0．99
0．47
0．65
0．43
0．48
0．46
1．16
0．53
4．39
4．12
3．09
3．86
3．13
3．16
3．21
3．80
4．78
2．94
3．71
3．99
3．34
3．19
1．93
4．42
4．04
4．22
4．17
4．86
3．70
4．00
2．56
3．41
1．77
3．03
2，30
3．38
3．03
4．23
3．37
2．04
3．29
2．03
3．59
1．92
3．15
2．73
5．08
2．17
2．33
2．11
2．76
2．01
2．87
2．77
2．05
2．56
1．46
1．81
2．52
2．55
2．98
2．82
4．18
2．13
2．76
2．58
2．84
2．26
3．67
3．19
2．72
2．54
2．99
2．90
3．73
2．28
2．42
2．12
2．41
3．43
2．77
3．82
2．15
3．13
2．77
3．60
2，21
4．75
0．10
0．10
0．08
0．07
0．07
0．06
0．06
0．08
0．03
0．07
0．04
0．05
0．06
0．07
0．08
0，08
0．05
0．06
0．05
0．07
0．06
0．05
0．08
0．07
0．09
0．05
0．08
0．05
0．05
0．07
0．09
0．10
0．08
0．10
0，10
0．08
0．10
0．11
0．05
0．09
2．49
2．76
2．86
3．51
2．43
2．70
4．91
3．36
2．76
4．76
99．01
99．18
99．45
99．63
99．63
99．71
99．26
99．47
99．27
100．00
1．66 99．67
1．42 99．93
1．21 99．92
2．14 100．06
2．86 100．43
1．65 99．94
1．58 99．69
1．44 100．23
1．47 100．12
1．38 100．27
1．32 100．42
1．02 99．97
2．11 100．33
1．38 99．96
4．18 100．06
1．89 100．16
6．42 100．50
2．35 100．18
2．57 99．76
1．48 100．13
1．98 100．06
3．88 100．07
1．78 100．08
4．04
2．14
2．90
3．30
3．64
2．35
2．58
100．05
100．07
99．78
100．33
100．37
99．99
99．89
4 5634 4444 4964 4822 5602 5424 5293 5624 5404 480
5 5623 6163 5985 47310 5855 5943 5954 543
4 5874 65551066311624 4594 5819 4234 54313 5454 4785 5014 5223 43111 4505 565
Ω）56QU9n∠（U
1 2
508430434529531
496593
32 5136 51
33 4733 4431 2930 2846 6731 2655 18
41 137
16599350
53325336
60754685
（∠’一」1（∠3（∠ 」1
49 4042 5786 3392 2744 5544 8949 6948 2269 4941 2043 2041 63
54 10256 5344 58
4五可’一2五丁五可5
一！66一！一！66
9898640
41345
4
6693315514
1111111111
30132202
11114111
440189031114188
111111413111131
66228043
100 9
37
7431214351
1111111」－」［」一1411
11
141611
11
15
318241638934285
1111114－11
」一111106690イー6
2」I」1』12」11
6445332550
1111112122
16603587
21112112
299881038998211
213412222111222
963Qり」1只）6
2222322
5454459674
96682749
1
279976994876119
一 イー
イーイー
11
11
1010141210
3928960636
1 ’一 2 2
82474616
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706869289600934
12 224 2 12142
7145908
2」1232
2
6796066784
1111211111
0383291281
7685877745
16 7717 7619 9418 90
25 15716 5919 8219 88
21 9315 5718 9417 7017 9614 69
22 13716 10332 15714 7919 8616 6618 84
28 16418 97
8330209
2223222
17084
13911515750
158
10 418 8．4
11 275 9．2
7 264 8．7
9 364 7．4
7 240 9．4
7 252 7．7 7 210 11．8
8 365 7．7 8 175 11．5
13 195 11．4
6 141 11．2
4 154 9．2
4 193 9．4
618610．110 116 14．1
6 221 9．4
4 130 8．66 174 12．9
7 256 14．8
8 196 10．1
12 263 13．9 7 233 13．2
10 161 9．6
8 155 9．111 120 12．1
7 99 13．111 1’13 15．8
715110．3 6 166 12．1
8 229 9．3 8 160 12．5
11 132 14．5
10 207 12．0
3091359
ーイ［． 11
107127129127120123113
16．3
12．2
12．5
15．7
15．3
14．0
14．8
0130575401
1111102111
65172564
11112111
618908264982056
2100202Z3tα23乞Z
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2」122322
1826615862
7654445426
38157768
32346523
181541357080083
343255837325675
105428795
1151576
8755420528
1111112121
95899964
11112112
6819608746
4442334343
33129596
43447436
27 6320 5223 5322 5422 5816 4628 8624 7033 9021 3724 4019 50
22 47
31 10121 58
5364399
Qり3ク一332（∠
11779831561224689
145147127149125120181
13913589
145142152162159169123206
169138177182148116101
153179130149151
437117183
145232136166153193155
ζ馨【き葺§g一。暮旨き昌・・8亀ρ舞82里。言。。8ga一目。巨β§厨ぎ日旨旨巨鐘皇貫き。
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Table2 Major element and trace element analyses of Shimanto temne sedimentary rocks．
SA＃LITH SiO2TiO2A1203Fe203MnOMOCaONa20 K20P205 LOl SUM As Ba Ce CrCu Ga La Nb Ni Pb Rb Sc Sr Th U V Y Zn Zr
HIDAKAGAWA GROUP（ctd）NyunokawaNYI VFS 79．76NY2 VFS 78．30NY3 VFS 82．88NY4 MUD 65．69NY5 FS 81．24NY6 FS 78．85NY7 FS 79．32NY8 FS 82．44NY9 FS 76．97
0．25 8．92 2．67
0．22 9．27 1．88
0．20 9．04 1．29
0．72 18．45 3．39
0．19 9．55 1．36
0．22 10．05 1．85
0．24 9．91 2．02
0．20 8．78 1．44
0．25 9．60 2．25
0．07
0．16
0．01
0．01
0．01
0．03
0．03
0．03
0．10
OTONASHIGAWA GROUPUridanlOTI MUD 67．60 0．62 14．30 6．40 0．190T2 MUD 67．76 0．63 14．50 5．89 0．18
HarokuOT3 MSOT4 FSOT5 FSOT6 FSOT7 CSOT8 MUDOT9 MUDOT10FSOTll FS
OT12MSTOKl MSTOK2CSTOK3CS
77．33
77．86
80．00
78．79
80．01
80．36
67．13
83．07
79．26
79．75
79．23
80．36
81．65
MURO GROUPハ10臼7”」ER四βεL7昌
YasukawaYAI MS 79．18YA2 MS 79．26YA3 VFS 81．31
UchikoshiUCI MS 80．77UC2 MS 81．78UC3 FS 81．76
UC4 FS 81．39
UC5 MUD 65．04UC6 CS 84．46
0．20 11．12
0．21 10．13
0．14 9．70
0．18 10．12
0．15 10．45
0．18 9．88
0．64 16．70
0．19 8．84
0．17 10．60
0．16 10．0’1
0．19 11．00
0．17 10．32
0．16 10．00
1．76
2．00
1．69
1．83
1．38
1．46
4．51
1．19
1．25
1．”
1．35
1．17
1．06
0．03
0．02
0．03
0．05
0．03
0．02
0．04
0．03
0．02
0．02
0．01
0．01
0．01
0．81
0．82
0．37
1．40
0．33
0．52
0．56
0．38
0．81
1．25
1．62
0．29
0．16
0．26
1．26
0．76
0．68
1．89
2．47
2．96
3．40
1．85
3．64
3．42
3．01
3．52
3．14
1．56
1，66
1．56
4．15
1．95
1．96
2．03
1．34
1．84
0．06
0．05
0．05
0．10
0．04
0．05
0．04
0、05
0．05
1．96 99．78
2．49 99．43
1．02 100．11
4．24 100．16
1．00 99．57
1．51 99．72
1．63 99．55
1．08 99．94
2．70 99．60
2．39 0．32 2．32 2．27 0．10 3．24 99．76
2．31 0．40 2．41 2．38 0．10 3．34 99．90
0．61
0．67
0．60
0．68
0．40
0．42
1．50
0．44
0．42
0．35
0．55
0．60
0．40
0．83
0．44
0．91
1．09
0．51
0．86
0．25
0．66
0．59
0．87
0．13
0．28
0．11
3．40
2．38
3．64
3．74
3．07
3．61
1．20
3．20
2．56
2．85
3．32
3．16
2．99
2．76 －0．04
2．62 0．05
1．82 0．04
1．54 0．04
2．46 0．04
1．91 0．04
4．13 0．08
1．44 0．03
3．26 0．04
2．90 0．03
2．73 0．04
2．65 0．04
2．70 0．04
1．47
3．23
1．33
1．57
0．95
1．19
3．96
0．90
1．26
1．82
1．33
1．23
0．93
99．55
99．61
99．90
99．63
99．45
99．93
100．14
99．99
99．43
99．87
99．88
99．99
100．05
2 3563 3573 3728 5042 5003 4102 5371 3704 368
237352383
333744434
742703525
111611111
1811
126611
11
1211
11
998081169
（∠
」一」一
345008969
111321111
654654755
1
955176855
2
15 5713 5816 51
29 17216 62
18 6418 6716 3915 64
4 124 8．6 1．4 26
41358．21．3 24 3 88 9．9 1．2 19
13 95 16．2 3．0 139
3 147 10．7 1．6 16
5 137 10．4 ＜1．0 22
4 130 10．2 1．4 28
2 119 8．9 ＜1．0 20
415911．11．427
17 43 15416 31 13513 31 13829 121 167
12 41 16916 38 13814 37 14013 26 14521 39 171
4313 52 55 66 17 16 7 36 19 91 12 9110．21．8128 23 951075 293 48 57 64 17 17 9 34 24 92 12 92 10．0 1．1 130 22 93 113
3 575 1 549＜1 549 1 460
2 650 1 528
4 469＜1 493 1 625
2 520 1 593＜1 631 1 599
2637799449454
4344425433233
3568883087098
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0．28 10．74 1．84 0．02 0，63 0．21 2．51 2．85 0．05 1．15 99．54 2 585 30 18 12 10 15 5 5 14 88 3 132 7．4 ＜1．0 23 12 14 153
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2．19
2．69
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Table2 Major element and trace element analyses of Shimanto temne sedimentary rocks．
SANR LITH SiO2 TiO2 A』03Fe203 MnO M O CaO Na20 K20 P205 LOl SUM As Ba Ce Cr Cu Ga La Nb Ni Pb Rb Sc Sr Th U V Y Zn Zr
MURO GROUP（ctd》四〇RπfεRハ’β』ユ7
KogawaKOl FSKO2 FSKO3 FSKO4 FSKO5 VFSKO6 FSKO7 FSKO8 FSKO9 MS
78．93
80．47
78．71
82．66
78．60
77．27
79．26
77．95
80．37
0．28 10．94
0．28 10，30
0．28 11．09
0．25 9．44
0．28 10．80
0．33 11．45
0．29 10，53
0．28 10．47
0．19 9．34
SOσ7”εRハ’βεL7
WabukaWBI FS 81．49 0．24WB2 FS 82．17 0．27WB4FS 80．82 0．30WB6FS 79．60 0．26
MitogawaMTl MSMT2 MSMT3 MSMT4 MUDMT5 MSMT6 FSMT7 VFSMT8 VFSShimotsuyuSMl VFSSM2 VFSSM3 VFSSM4 VFSSM5 VFSSM6 VFS
84．47
85．30
81．57
78．84
81．72
78．78
78．62
75．94
80．34
76．83
82．25
70．04
74．61
79．08
9．34
8．88
9．20
9．28
0．19 8．32
0，17 7．87
0．24 9．83
0．28 10．25
0．23 9．22
0．29 10．32
0．31 11．02
0．45 11．11
0．35 9，77
0．47 11．35
0．22 7．70
0．67 14，16
0．48 11，87
0．33 10．23
POST・SHIMANTOTanabe GroupTNI VFS 80．72 0．36
TN2 VFS 81．02 0．30
TN3 VFS 81．14 0．32
TN4 VFS 82．61 0．28
Kumano GroupKMI SLT 71．26 0．55KM2 SLT 69．27 0．63KM3 SLT 72．89 0．56
10．29
9．28
9．85
9．38
1．95
1．53
2．08
1．24
2．34
2．52
1．79
1．95
1．13
2．03
2．24
2．63
3．43
0．92
1．02
0．86
3．03
1．95
2．68
1．28
4．16
1．99
2．87
1．70
4．95
2．84
2．37
13（∠7
（∠130
111。「1
0．03
0．03
0．03
0．03
0．02
0．03
0．02
0．04
0．03
0．02
0．02
0．02
0．02
0．00
0．01
0．01
0．03
0．02
0．02
0．02
0．03
0．04
0．04
0．04
0．06
0．04
0．05
0．01
0．03
0．01
0．01
0．78
0．61
0．88
0．49
0．92
0．80
0．63
0．65
0．33
0．57
0．56
0．67
0．76
0．31
0．46
0．44
0．65
0．45
0．51
0．58
1．00
0．56
0．88
0．48
1．42
0．90
0．66
0．57
0．60
0．59
0．48
0．12
0．14
0．12
0．20
0．21
0．32
0．30
1．14
0．81
0．25
0．26
0．25
0．25
0．11
0．10
0．26
0．04
0．10
0．08
0．49
0．26
0．44
0．56
1．61
0，70
1．52
0．38
0．11
0．77
0，10
0．10
2．77
2．65
2．81
2．73
2．87
2．57
2．99
2．91
2．11
2．11
2．18
2．16
2．01
2．67
2．38
2．90
1．83
1．84
2．10
3．67
1．93
2．97
3．42
2．73
2．76
3．43
2．93
3．13
2．63
2．97
2．80
2．45
2．28
2．21
2．09
2．33
2．62
2．75
2．41
3．31
2．78
2．48
2．60
2．89
2．14
2．25
3．07
3．33
3．24
3．60
2．93
2．89
2．26
1．87
1．47
2．44
1．65
2．57
2．35
2．18
2．26
2，27
0．04
0．04
0．04
0、04
0．05
0．05
0．05
0．05
0．04
0．05
0．05
0．05
0．05
0．02
0．02
0．05
0．03
0．06
0．05
0．05
0．07
0．06
0．08
0．05
0．10
0．08
0．06
0．05
0．04
0．05
0．05
1．29
1．14
1．43
0．80
1．47
1．56
1．18
1．77
2．20
0．84
0．87
0．87
0．91
0．59
0．61
0，66
1．20
0．96
0．97
0．63
1．58
0．80
1．15
1．63
2．35
2．21
0．91
0．98
1．46
0．95
0．85
99．58
99．47
99．68
99．97
99．89
99．52
99．79
99．62
99．86
99．72
99．98
99．57
99．46
99．74
100．19
99．89
99．51
99．79
99．40
99．60
99．42
99．58
99．52
99．88
99．65
99．63
99．57
99．78
99．44
99．56
99．90
11．52 5．74 0．13 2．26 0．49 1．96 3．15 0．09 2．41 99．56
13，56 4．80 0．10 1．87 0．56 2．61 3．82 0．09 2．42 99．73
13．03 3．07 0．07 1．02 0．57 4．91 2．31 0．06 1．13 99．62
1 5561 5751 4781 5821 601
＜1 5401 5261 5013 717
1 608＜1 543
3 6312 769
＜1 540
2 560＜1 782＜1 691
1 735＜1 810
2 635＜1 672
6 7416 5368 5196 5394 4154 730
∩∠」一∩∠」一
492467483509
752362487
453943352
4508
334337992480
52333133
2」13」17「〆
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777509681
111121111
14161918
42592904
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4228
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3 682 46 52 40 15 16
3 769 47 56 46 15 19
6 785 43 39 20 11 23
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9686
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10 5510 5812 84
12 10813 95
13 10513 83
10 95
324122
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7649685只u」一0
～ノ6一！「ノ
41109．61．3510311．51．65 104 8．9 ＜1．0
411814．41．05 120 9．2 1．4
5 123 8．7 1．6
5989．5＜1．06 127 10．6 1．0
3 146 6，8 1，1
2 1162 722 93
＜2 107
＜2 123＜2 1272 1613 86
＜2 96
2 1093 2204 101
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6．8 ＜1．0
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6．7 ＜1．0
8．6 ＜1．0
7．2 1、0
9．4 1．2
＜2 153 7，2 1．1
417210．11．2 21986．1＜1．0 9 132 12．1 2．4
5 197 9．9 1．8
31067．01，0
323（∠
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6858
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3232
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8
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1016
27 15027 19743 11860 24928 15048 11713 12339 14016 113
014（∠
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122」1
43344 1114 1047 1514 15311 1302 17116 18513 303
16 14 28125 18 36314 118 15725 36 27016 42 30613 50 207
（∠」188
イー－ 一
！635
2532
295238201149
7 18 13 98 10 84 9．8 2．4 87 25 147 121
9 19 12 121 10 102 10．9 3．3 92 23 25 144
8 6 22 59 9 108 10．1 1．4 58 29 44 191
三碧轟医欝。。。一。暮旨き葺の。の。らρ。§。8。・ε峯。。8。の。α一馨巨鳶§犀。・ぎ日一『。浮ぎき88旨き。
困モ。乱暴乱僧の≦一碧き
ひい
66 Barry Roser，Hiroaki Ishiga，Takanori Bessho and Kaori Dozen
pan－the Miyama，Ryujin and Nyunokawa foma－
tions．Jio麗rnα1ρプ∫h8 G80109∫oαl Sod8砂 ρプJl卯）αn，
103，377－390．＊
Ch麺iwa，K．1988．Post－Shimanto sedimentation and
organic metamolphism：an example of the Miocene
Kumano Group，Kii Peninsula．〃io4αn G60108』y，12，
363－387．
Hisato血，K．1988．The Miocene forearc basin of
Southwest Japan and the Kumano Group of the Kii
Peninsula．ルfo48rn G801081y，12，389－408．
Kashima，N．1992．Sandstone composition and sedi－
mentary environments of the Cretaceous System in
westem Shikoku．〃餉oirsげ∫hεGεolo8ぎ。αl Soo∫のノ
ρプ1角ραn，38，291－297．＊
Kimura，G．1997．Cretaceous episodic growth of the
Japanese Islands．T〆z8／lslαn4Arc，6，52－68．
Kimura，K．，Bessho，T．，Sakamoto，T．，Kumon，F．and
Suzuki，H．1996．Fission－track ages and their signifi－
cance of acidic tuff in the Upper Cretaceous Ryujin
Fomation of the Shimanto Supergroup，Kii Penin－
sula，Southwest Japan．10配rnα1げ∫h6G60108・∫oαl So－
oi6芝yρデ1叩αn，102，116＿124＊．
Kumon，F．1983．Coarse clastic rocks of the Shimanto
Supergroup in Eastem Shikoku and Kii Peninsula，
Southwest Japan．〃1αηoかsげ∫h8Fαc配1乏yげSci8nc8，
絢。∫o Un’v6rs∫砂，S67’6sヴG60108・yαn4ルf∫n8mlo8・y，
49，63－109．
Kumon，F．，Suzuki，H．，Nakazawa，K．，Tokuoka，T．，
Harata，T．，Kimura，K，Nakaya，S。，Ishigami，T．and
Nakamura，K．1988．Shimanto Belt in the Kii Penin－
sula，Southwest Japan．ル1046rn G召olo8y，12，71－96．
Kumon，K．and Kimina血，K．1994．Modal and che面一
cal compositions of the representative sandstones
from the Japanese Islands and their tectonic implica－
tions．Proc664’n8s ρプ∫h8 29∫h ln∫6rnα∫’onα1 σ80－
lo8icαICongr8ss，PαπA，135－151．
McLennan，S．M．，Hemming，S．，McDanie1，D．K．and
Hanson，G．N．1993．Geochemical approaches to
sedimentation，provenance and tectonics．G80108∫cαl
Soo∫8リノρゾA〃zε7ioα51ρ86’α1ρ叩6r284，21－40．
Nesbitt，H．W．and Young，G．M．，1982．Early Protero－
zoic climates and plate motions inferred from m司or
element che血stry of lutites．八厩麗r8，299，715．717．
Norrish，K and Hutton，J．T．，1969．An accurate X－ray
spectrographic method for the analysis of a wide
range of geological samples．G80chin¢∫cααCos7no－
ohinzicαAαα，33，431－453．
Ogawa，Y．，Hisada，K．and Sashida，K． 1988．
Shimanto Supergroup in the Kanto Mountains－A
review．〃lo‘16rn G80108・y，12，127－146．
Ohmuri，K．，Taira，A．，Tokuyama，H．；Sakaguchi，A．，
Okamura，A．；Aihara，A．1997．Paleothemal stmc－
ture of the Shimanto accretionary prism，Shikoku，
Japan：Role of an out－of－sequence thmst．G80108・ly，
25，327－330．
Palmer，K．1990．XRF analyses of granitoids and asso－
ciated rocks，St．Johns Range，South Victoria Land，
Antarctica．Wα07iα Un∫v6rsi芝yげW411in8∫on，R6－
s8α7ch Schoo16ゾEαπh Sc∫8no8s G60108y Boαr4ρプ
S魏4’εs P麗わ1∫cα∫∫on，no．5，23PP．
Roser，B．P．and Korsch，R．J．，1986．Determination of
tectonic setting of sandstone－mudstone suites using
SiO2content and K20ZNa20ratio．10麗rnα1ヴσ601－
08y，94，635－650．
Roser，B．P．，Grapes，R．H．and Palmer，K1995．XRF
analyses of sandstones and argillites from the Tor－
1esse terrane，New Zealand．ViαoriαUn∫v8rs’乏yφ
W811ing∫on，R8s8α7ch SchoolρプEαr∫h Soi6no6s G6－
ology Boαr4ρプS∫麗4’8s Pκわlicα∫ion，no．17，40PP．
Roser，B．Sawada，Y．and Kabeto，K．1998．Cmshing
perfomance and contamination trials of a tungsten
carbide ring mill compared to agate grinding．
G60sci8nc8R印。πsψゾShiアnαn8Univ8rsi芝y，17，1－9．
Suzuki，H．，Harata，T．，Ishigami，T．，Kumon，F．，
Nakaya，S．，Sakamoto，T．，Tateishi，M．and
Tokuoka，T．；Inouchi，Y．1979．σ8010gyげ∫h8κ配r一
’sα8αwα 4ガsか●∫c∫． Quadrangle Series scale 1：50 000，
Geological Survey of Japan，54pp．＊
Taira，A．，Katto，J．and Tashiro，M．，Okamura，M．，
Kodama，K．1988．The Shimanto Belt in Shikoku，
Japan－Evolution of Cretaceous to Miocene accre－
tionary prism．Mo48rnσ80108y，12，5－46．
Tateishi，M．，Bessho，T．，Harata，T．，Hisatomi，K．，
Inouchi，Y．Ishigami，T．，Kumon，F．，Nakaya，S．，
Sakamoto，T．，Suzuki，H．and Tokuoka，T．1979．
G8010gy6ゾ∫h6Es研n∫4’s∫rio∫．Quadrangle Series
scale1：50000，Geological Survey of Japan，65pp．＊
Teraoka，Y．and Okumura，K．1992．Tectonic division
and Cretaceous sandstone compositions of the
Northem Belt of the Shimanto Te皿ane，Southwest
Japan．ルf8〃zoirsρプ∫h8 G80108∫（フαl Soci8乏y6ゾJrのワαn，
38，261－270．
Tokuoka，T．，Harata，T．，Inouchi，Y．，Ishigak1，T．，
Kimura，K．，Kumon，F．，Nak句。，K．，Nakaya，S．，
Sakamoto，T．，Suzuki，H．and Taniguchi，J．1981．
G60108・yρプ∫h8Ryゆn‘1∫s∫r’α．Quadrangle Series
scale1：50000，Geological Survey of Japan，69pp．＊
Tokuoka，T．，Harata，T．，Suzuki，H．and Yao A．1982：
Major and trace element analyses of Cretaceous to Miocene sedimentary rocks from the Shimanto temne，
Kii Peninsula，SW Japan
Tanabe．Geological Survey of Japan1：200，000sheet
NI－53－16．
Yanase，A。1992．Vitrinite reflectance and origin of
melanges in the Cretaceous Shimanto Belt，eastem
Shikoku，Southwest Japan．10泥rnα1ρプ∫h8（｝80108・icα1
Soc∫8乏yψゾJl叩αn，102，13－24．＊
＊In Japanese；English abstract or summaly．
（Received：130ct．1998，Accepted：200ct．1998）
67
（要 旨）
Barry Roser・石賀裕明・別所孝範・道前香緒里，1998、西南日本紀伊半島の白亜系～中新統
の堆積岩の主元素・微量元素の分析，島根大学地球資源環境学研究報告，17，57－68
白亜紀から中新世の地層群からなる西南日本の四万十帯は地質学的にはよく研究されてき
た．しかし，地球化学的検討はわずかに行われているにすぎず，全岩化学組成はの報告は少
ない．そこで本報告では，紀伊半島，和歌山県において採集した砂岩と泥岩の100試料につ
いて蛍光X線分析を行った．分析は主元素と19の微量元素（As，Ba，Ce，Cr，Cu，Ga，La，Nb，
Ni，Pb，Rb，Sc，Sr，Th，U，V，Y，ZnおよびZr）について行った．さらに，田辺層群と熊野層
群がら採集した7試料についても同様に分析を行った．本論ではこれらの分析結果を報告す
る．
68 Bany Roser，Hiroaki Ishiga，Takanori Bessho and Kaori Dozen
APPENDIX二Sample Iocalities Appendix：Sample localities．
SAヂ longitude Latitude local name SA＃ longitude Latitude L㏄al name
HIDAKAGAWA GROUP OTONASHlGAWA GROUP（ctd）
YukawaYl
Y2Y7Y9Y12Y13Y14Y16Y17Y18
135。2710911
135。2ア16“
135。26115・1
135。26，1911
135。26，1701
135。26，151－
135。26，1811
135。2611411
135。25156“
135。25盲3011
Miyama
12345678
MMMMMMMM
135。1412911
135。14暫16館
135。17’4011
135。1715611
135。17，5611
135。175611135。21’50闘
135。22，08”
Te陥somaTE1 135。121351－
TE2 135。12’39”
TE3 135。12’36”
TE4 135。12’401’
TE5 135。12軍40”
TE6 135。12’4011
TE7 135。12’4α1
TE8 135。12’59”
TE9 135。13，0011
TE10 135。13，0011
TE11 135。13100翻TE12 135。14’23’I
TE13 135。14’23’1
TE14 135。14，16朋
TE15 135。14’131’
Ryujin
RYlRY2RY3RY4RY5RY6RY7
135。22137”
135。22暫37飼
135。26’1011
135。25，001’
135。25，0011
135。2513311
135。25133塵1
NyunokawaNYlNY2NY3NY4NY5NY6NY7NY8NY9
135。26’40麗
135。28，15髄
135。28’3311
135・28，3311
135。2811511
135。3510811
135。35，08胴
135。34，42”
135。34108一’
34。031271［
34。03’30胴
34。03，451臨
34。03，5411
34。04，02雛
34。041041’
34。04，1111
34。04，20”
34。04，28肥
34。041191’
33。5514611
33。58’43”
33。58，0511
33。5812211
33。58123閣
33。58じ28II
33。58100”
33。5ア3411
33。59，0811
33。59113鯛
33。5911311
33。59114”
33。5911411
33。59，1411
33。59，14”
33。58，14肥
33。58114”
33。581141’
33。58，14”
33。57’4411
33。5744”33。53，4411
33。531431’
33。56’58闘
33。56’58”
33。56，03闘
33。55’16”
33。55’16”
33。55じ12腔
33。55「12”
33。53，00闘
33。53’0α1
33。52，4311
33。52143”
33。51，47聡
33。53，07朋
33。53，07開
33。53’3311
33。53141開
OTONASHlGAWA GROUP
Shimizu・cho，Shimoyukawa，NakamuraShimizu・cho，Shimoyukawa，NakamuraShimizu・cho，Shimoyukawa，KurataniShimizu－cho，Shimoyukawa，KurataniShimizu・cho，Shimoyukawa，N of Kuratanl
Shimizu・cho，Shimoyukawa，N of Kuratani
Shimizu－cho，Shimoyukawa，N of Kuratani
Shimizu・cho，Shimizu，OkunoShimizu－cho，Shimizu，east of Okuno
Shimizu－cho，Shimizu，west of Okuno
Kawabe・cho，HiragawaKawabe・cho，HiragawaNakatsu・mura，north of Takatsuo
Nakatsu・mura，north of Takatsuo
Nakatsu・mura，north of Takatsuo
Nakatsu・mura，north of Takatsuo
Miyama－mura，south of KawaragouMiyama・mura，south of Kawaragou
Hirokawa－cho，SarugawaHirokawa・cho，SarugawaHirokawa・cho，SarugawaHirokawa・cho，SarugawaHirokawa・cho，SarugawaHirokawa・cho，SarugawaHirokawa・cho，SarugawaHirokawa・cho，south of Terasoma
Hlrokawa・cho，south of Terasoma
Hirokawa・cho，south of Terasoma
Hirokawa・cho，south of Terasoma
Hirokawa・cho，KotsurudaniHirokawa・cho，KotsurudaniHirokawa－cho，Kotsurudani
Hirokawa・cho，Kotsurudani
Miyama・mura，TakigashiraMiyama・mura，TakigashiraRyujin・mura，ea就of Oie
Ryujin・mura，Kainokawa，OoseRyujin・mura，Kainokawa，OoseRyujin－mura，Kainokawa，OoseRyujin・mura，Kainokawa，Oose
Ryujin・mura，Fukui
Ryujin・mura，YanaseRyujin・mura，east of Yanase
Ryujin－mura，east of Yanase
Ryulin・mura，north of Toragamine
Nakahechi■cho，S of Sakayasu tunnel
Nakahechi帰cho，SofSakayasutunnelNakahechi・cho，NyunokawaNakahechi・cho，Nyunokawa
Haroku（ctd）OT10 135。3510011
0T11 135。35。1911
0T12 135。35115“
TOK1 135。14’10”TOK2 135。14『0’I
TOK3 135。1411011
MURO GROUP
33。5f211133。52’1611
33。52141胴
33。46153闘
33。46，53”
33。46曹53臆
ハ’0月17「Hε月ハ’BELア
YasukawaYA1 135。38’25” 33。44’5011
YA2 135。38148” 33。4510011
YA3 135。38電5011 33。441581’
UchikoshiUClUC2UC3UC4UC5UC6
Kogawa
123456789
000000000
KKKKKKKKK
135。36154”
135。3614611
135。3613611
135。3515611
135。35’31”
135。35131開
135。3010411
135。3α041－
135。3α0411
135。31「08腿
135。31’0811
135。3110011
135。3110011
135。30154鵠135。36冒35一’
SOU71Hεηハ’8εL7
WabukaWB1 135。37’52”WB2 135。37’521IWB4 135。37’52”WB6 135。37’52’1
Mitogawa
ま ヨ さ
椰冊冊冊冊冊研旧
135。30冒461’
135。3α46・1
135。30，46盤
135。32，101’
135。32壁101’
135。32107翻
135。35’33”
135。35，311’
Shlmotsuyu
ーハ∠3456
MMMMMM
SSSSSS
135。41’35”
135。41，3511
135。41じ3511
135。41’351’
135。41，35脈
135。4113511
33。47’2811
33。47’161I
33。46曹40’1
33。46じ3011
33。46135“
33。46，3511
33。45113闘
33。45’1311
33。451131I
33。45，5611
33。45，56朋
33。46’0011
33。46105”
33。46，1011
33。47，5211
33。3α16鯛
33。36113胆
33。36113”
33。36曜13”
33。31，511’
33。311510’
33。31’5111
33。3f21醐33。31121陥
33。31161麿
33。3α00醜
33。30，0011
33。29，05叫
33。29’051書
33。29105”
33。29’05朋
33。29105，1
33。29曜0511
Nakahechトcho，Tom忙a R，
Nakahechトcho，Tom吐a R．
Nakahechi・cho，Tomka R．Kirimi・zaki
Kirimi・zaki
Kirimi・zaki
HyouzeiNofHypuzeiNofHypuzei
Ohtou－mura，east of Shimogawakami
Ohtou－mura，east of Shimogawakami
Ohtou・mura，east of Shimogawakami
Nakahechi・cho，NE of Takanosu－yama
Nakahechi－cho，NE of Takanosu・yama
Nakahechi・cho，S of Takanosu・yama
Nakahechi・cho，S of Takanosu・yama
Nakahechi・cho，SWofTakanosu・yamaNakahechi－cho，SWof Takanosu－yama
Nakahechi－chou，HokusogiNakahechi・chou，HokusogiNakahechi・chou，HokusogiNakahechトchou，west of lshiburi
Nakahechトchou，west of［shiburi
Nakahechトchou，west of lshiburl
Nakahechi・chou，west o斜shiburi
Nakahechi－chou，west of lshiburi
Nakahech卜cho，south of Chikatsuyu
Susami－cho，south of Satono
Susami－cho，south of Satono
Susami・cho，south of Satono
Susami－cho，south of Satono
Susamトcho，KuchiwabukaSusami－cho，KuchiwabukaSusami・cho，KuchiwabukaSusami－cho，KurosakiSusami－cho，Kurosaki
Susamトcho，KurosakiSusami－cho，EsumisakiSusamトcho，Esumis職ki
Kushimoto・cho，TakoKushimoto－cho，Tako
Kushimoto・cho，TakoKushlmoto－cho，TakoKushimoto・cho，TakoKushimoto・cho，Tako
UridaniOT1 135。31，19“
OT2 135。3ず19朋
Haroku
犯脚朽鴨ηmm
OOOOOOO
135。33125■1
135。33125・1
135。3410611
135。34106館
135。34148’1
135．3414811
135。3510011
33。47143”
33。4738腿
33。4815111
33。48事5111
33。49146麗
33。49146”
33。50’10闘
33。50113「’
33。51騨21聡
Nakahechi－cho，KurisugawaNakahechi－cho，Kurisugawa
Nakahechi・cho，Hebikoshi
Nakahechi・cho，Hebikoshi
Nakahech卜cho，nortbofFukusadaNakahechi－cho，north of Fukusada
Nakahechi・cho，Tom醗a R．，S of Hyouzei
Nakahechi・cho，Tom置a R．，S of Hyouzei
Nakahechi・cho，Tom杜a R．，Hyouzei
POST－SHIMANTO
TanabeGroupTN1 135。25’50開TN2 135。25’50雛
TN3 135。25，50’畢
TN4 135。25150鯛
33。34105醐
33。34105”
33。34，05闘
33。34105”
Kumano GroupKM1 135。44’1511 33。28’56’I
KM2 135。44騨15闘 33。28’56’‘
KM3 135。44騨15” 33。28’56”
Hikigawa・cho，Hiki
Hlkigawa・cho，Hiki
Hikigawa・cho，Hiki
Hikigawa・cho，Hiki
Kushimoto－cho，Ar醗a
Kushimoto－cho，A蹴aKushimoto・cho，Ar薩a
