A Study on the Pollen Stratigraphy of the Osaka Group, Title Pliocene-Pleistocene Deposits in the Osaka Basin
Author(s) Tai, Akiko
Memoirs of the Faculty of Science, Kyoto University. Series of Citation geology and mineralogy (1973), 39(2): 123-165
Issue Date 1973-02-28
URL http://hdl.handle.net/2433/186585
Right
Type Departmental Bulletin Paper
Textversion publisher
Kyoto University MpMolRs oF THE FAauLTy oF ScmNcE, KyoTo UrglvERsl ry, SERIEs oF GEoL. & MINERAL., Vol. XXXIX, No. 2, pp. 12¥3-1as, Feb. 28, 1973
A Study on the Pollen Stratigraphy of the AOsaka Group, Pliocene¥Pleistocene Deposits inA the Osaka Basin
By Akiko TAi'
(Received Sept. 30, 1972)
Abstract
From the view point of the pollen stratigraphy, the Osaka group, the typical Pliocene-Pleistocene deposits distributed in the Kinki district, Central Japan, is divided into Metasequaia Zone below and Fagzas Zone above. Those divisions correspond with the stratigraphical units, that is, the Lower formation and the Upper formation of the Osaka group respectively. The former zone is character- ized by the decrease of the Tertiary type tree pollen and the increase of the coniferous tree pollen which are present in Japanese Islands, and further it is subdivided into A-D subzones ascendingly. The marine beds of the latter are characterized by the high percentage of Fagus pollen, and a spectmm obtained from tlie fresh water bed shows the po11en composition consisting of cool-temperate to cold climate. Basing upon the compositional oscillation of the pollen diagram in regard to lithofacies changes, Fagus zone is subdivided into E-H subzones. As to the climatic changes, the first distinct cool phase is supposed to be at the boundary between B and C subzones. The climatic oscillations are assumed to occur once or twice in each subzone of which oscillation of F subzone is most distinct. During the advance from A to H subzones, the shift of the warm forest seerns to have began from the mixed-forest composed of the Tertiary type coniferous trees and variegated broad-leaved trees (especially represented by high percentage of Quercus pollen) to the single tree forest such as Cmptomem'a or Fagtts fqrest. At the time of H subzone, the forest which is composed of evergreen Qteerctts ac- companied with warm-temperate trees (PodocarPas, Palittrus, etc.) appeared in some parts, probably as the secondary forest. As to Fagus, it may bc probable that the differentiatien of warm-temperate and cool-temperate types took place at least at the time of G and H subzones.
I. Introduction
The analysis of the history of the fiorae since the Late Pliocene provides im- portant and attractive problems in the Quaternary research. In Japan, it was first that MiKi (1948) made a synoptical work with the description of the Pliocene and Pleistocene plant remains found from the Kinki district, Central Japan, to which great attention was given. In recent years numerous data on the stratigraphy and the fossil records of the Osaka group have been obtained. Due to those im- portant and manifold informations, it becomes possible to discuss the vegetational sequence in some detail. Besides the investigations on the stratigraphical succession of the Osaka group
* Present addfess. 67, Misasagi-kamotocho, Yamashina, Higashiyama-ku, Kyoto City. l24 Akiko TAi
("OsAKA GRoup" REsEARcH GRoup, 1951; ITiHARA et al. 1955; ITiHARA, 1960), the combination of the stratigraphy and the flora has been made by many authors (HuziTA, 1954; ITmARA, 1960; 1961 ; ITiHARA et al., 1955; 1965; KoKANNrA, 1961; NiREi, 1968). But, in order to clarify the outline of floral changes more precisely, the pollen analytical study has been requisite. The palynological study on the Osaka group and its correlatives has been ex- ploited by SHiMAKuRA (1959; 1964; 1965), and the study of the pollen stratigraphy has been promoted by ONisHi (1968), ONism and NAsu (1968), NAsu (1970), and the present writer (TAi, 1963; 1964; 1966; 1969; 1970 a, b). In this paper the writer wishes to present a standard pollen stratigraphy of the Osaka group and to give general aspect on the floral change in the Kinki district since the Late Pliocene. Recently, as to the Osaka group and its correlatives, the stratigraphical, paleontological, paleomagnetic and radiometric studies have been carried out under the cooperative works of 1966-68 subsidized by the fund of the Ministry of Education, and the results have been summarized by many authors (TAKETsuzi and ITiHARA, 1967; KAMEi, 1969; KAMEi and SEToGucHi, 1970; IsHiDA et al., 1969; NisHiMuRA, 1969; NisHiMuRA and SAsAJiMA, 1970; ITiHARA and KAMEi, 1970). On the basis of the above-mentioned results in addition to the writers palynological study, the present writer will give her considerations on the following subj ects : 1) The pollen zones of the Osaka group. 2) The tree-kind analysis presumed from the combination offossil pollen and plant remains. 3) The floral and c]imatic changes during the Late Pliocene and the Early Pleistocene.
II. Method and Materials
Materials Localities and stratigraphical horizons from which the materials were taken are shown in Figs. 1-5, respectively. Materials, about 500 g each, were sampled at the vertical interval of 20 or 10 cm in the type section (Tsuchimaru, Senriyama, Hirakata and Machikaneyama). Skeleton diagrams are prepared from samples of 40cm vertical interval. The samples of the intervening position were also examined if necessary.
Procedure of PreParation To prepare the samples, the writer used the SHiMAKuRA's method (SHiMAKuRA, 1956) and its improved one (TAi, 1969). Namely, the following procedures were carried out in usual manner. Dispersion of the sample by 10 percent (aqueous solution of) KOH Aextraction of the colloidal clay by washing -spreparation by mixed acid, i.e., HCI: HN03: H20 (1 : 1 : 1) .extraction of the soluble substances A Study on the Pollen Stratigraphy of the Osaka Group 125
-" Ky6to O AIIuvium / llIIIIIIIIIll Lower-Middle Terrace Depositf /li'' - Higher Terrace Deposits ttt. ./il I:l:IIIg upper Part of osaka Group ¥.f '¥ww. ¥¥. ,S Uji :-:-l.l:i:.:'1 Lower--Lower most of Osaka Group /;-- Basement Rocks .., 'i''}' ""/" -'k',r¥,-,`¥1¥l::.:.' -::-t-- .I I'X='ee'{'¥¥ /" Fault ,"ii/ll"i''' .. ,., 1///.l,E.EE.lt/tt¥'/ =
' ' Ibaragi fSl/;"ir,a,, yonaka 10 Si,':'.ge.ii.':E: i nl Mt.Rokkugegg e,,' ,r . .t.t//t. :./, .i/ll,,/111.111'-/.¥' }3- -- E!¥. ,1. y:. ''.lme. .¥gtl¥/. .. t .1. zattff ttttlt :E Nishinomiya t/ ttll tll) lt .-U .t /lt li .IS'..tt/t/ttt t tt ttttt tt' ' .,,T- .' N gO Mt.Ikoma t Osa a e Xern ci pt.. tK6be - ! 4 Kawac i l
a a O$aka bay Mt.Nijo
"ie. ma -:- -- - , "':'::::'-:':'i -:--= ," ...:.l.:-1 -::::-----J------.- ':':i:. :::.I:::.:.:.::: :--t- - ::--::-:-: - - ' 'i'" .:' :-1-:.: :.l., ';'"'-":':i;
Senna ,m/ l¥/', .. , .,- '//-i-E'' -. -
, ,,,}./g'l. . ,., },11 tt-, .,t ¥:¥ l¥i,,'¥iil/13ill.ll.,¥.---t- ttt 'Li 3- s- i, 'l'Å}"•
/ttt...1, ,. - ll.ll//1i,, P' O 5 10 15km -H ' ¥ ,.,/5,.fi- .. AM'
Fig. . l. The locality map showing the sampling sites (geological map according to ITTHARA, 1966). 1:Fukakusa, 2:Hirakata, 3-1:Tannowal, 3-2:Tannowall, 4:OD-1(Tanaka motomachi,Minat"ku,OsakaCity), 5:Machikaneyama, 6:Tsuchimaru-Oike, 7: Central part ofSenriyama Hills, 8;Gokenya, 9:Manzidani, 10:Toyonaka, 11: Kornyo-ike, 12:Imakuma, 13:Fukakusa, 14:Mitsuike, 15:Bussharito,Hirakata. 126 Akiko TAi in alkali by 10 percent (aqueous solution of) KOH -Ncondensation of waste plant residue by centrifuging jextraction of Si02 by HF Aacetolysis preparation A mounting in glycerol jelly.
Indication of anal!tical results Microscopic observation of the pollen grains was done under the magnification of 400x or 600x, and 1,OOOx (immersed in oi,1) if necessary. Except for Alnus, the number of the pollen grains was so counted that the number of the tree pollen exceeded 200, but in some samples, it was impossible to count the exact number. In several samples, the frequency distribution of the pollen grain size was estimated for Tsuga, Taxodiaceae type, Quercus, Picea and Fagtts-pollen. The size of about 50-100 pollen grains was measured for each pollen type in every sample. As to the distribution type of the grain size and the modal position, the simplified indica- tion of each pollen type treated here will be described briefly as follows. Tsuga pollen: Tsuga pollen having normal grain size distribution has the evaluation of the mode which is grouped into three, that is, 60 pt-, 70 pa- and 80 ps- groups (TAi, 1964). Therefore, in the present paper, Tsuga pollen is classified as Tsuga K, Tsuga S and Tsuga D, respectively, and the intermediate types are indicated by like as Tsu,ga S-K and Tsuga D-S. Picea pollen (TAi, 1963): As the pollen grain of this sort is apt to receive breaking down and distortion in the sediments, the frequency distribution curve of the grain size seldom shows normal distribution. The distribution is separated into two groups, i.e., the group with the center of the distribution being below 1OO ps (B type distribution) and the other with that above 1OO ps (A type distribution). In the latter group, characteristic pollen of Picea A are found. Taxodiaceae type pollen (TAi, 1963, 1966): The evaluation of the mode is separable into two parts at the point of 30 pa in grain size. Taxodiaceae type pollen which show a larger mode than 30 pa is called as Taxodiaceae II type and the name of Taxodiaceae I type is given to that having the smaller mode than 30 pt. Furthermore, Type I is separated into two types, i.e., I-a type of normal distribution, and I-b type which shows an intermediate type between I-a type and II type. Fagzas pollen (TAi, 1969): This pollen group includes two types in grain size distribution, i.e., the type in which the evaluation of the mode occupies in the vicinity of 35-36 pa and the type which has the evaluation in the vicinity of 40 pa. The former is called Fagus-S, and the latter is called Fagus-L. Quercus pollen (TAi, 1963): Of those whose frequency distribution of the grain size shows normal curve, Quercus pollen has the evaluation of the mode separable into two groups, i.e., the one distributed in the vicinity of 22 to 24 ps and the other above 28 pa. The former is called Quercus E and the latter is called AStudy on the Pellen Stratigraphy of the Osaka Group l27
QLuerctts D. The intermediate type is called Quercus D-E. Some of the above-mentioned fossil pollen grains corresponding to living species are given in Table 1.
III. Stratigraphy and the ponen analyses of Osaka Group
StratigraPhJ The Osaka group distributed in the Setouchi Geological Province is a product of the deposition during the Late Pliocene and Early Pleistocene. In many p!aces
Table 1. Grain sizes of pollen from living tree and correlative fossil pollen. 1-a. Coniferous, tree, 1-b. Broad-leaved tree. AfterJ, UENo (1951, 1957, 1958), VAiN. CAMpo (1950), M. IKusE (1956),J. NAKAMuRA (1956), M. TAKEoKA (1959), and A. TAi (1969). Tab. 1-a
The type of size of pollen Species Grain fossil pollen
Piceajezoensis var. hond oensis ? Piceajezoensis 80Å~43Å~47 68 Å~ 82 78 Picea bicolor 73Å~41Å~46 Picea (B) 73 Picea koyamai 85Å~47Å~47 85 Picea maximowiczii ? Picea polita 90Å~50Å~52 90
Picea koribai ? Picea (A)
Tsuga diversifolia 88 78-85 Å~ 78B5 Tsug. a-D 71 82 (mode)
Tsuga sieboldii 69 66 Tsuga-S 72 (mode>
Tsuga oblonga ? Tsuga-K ?
Metasequoia disticha ¥ 19-28 Taxodiaceae type I Metasequoiajaponica ?
Sequoia sempervirens 33A2 L Glyptostrobus pensilis 36-43 Å~ 38-46 2&34 Taxodiaceae type II 27-29 Å~ 30-33 Cryptomeriajaponica 24-32 30-33 Å~ 3tl--39 i 1 128 Akiko TAi
Tab. 1-b
Grain size of pollen The type of Species fossil pollen
Quercus glauca r 19-19.5Å~21.5-23 d 21.60 (mode) 22.20 (rnode) Quercus gilva 24.00 (mode) Quercus-E 22.20 (mode) Quercus phyllyreoides 21.96 (mode) 20-23Å~23-25.5 22.20 (mode) L Quercus rubroidea ? ? Quercus hikitai ? ?
Quercus mongolica l var. grosseserrata 28.80 (mode) f 23-24.5Å~27.5-30 Quercus serrata 28.80 (mode) 22-2SÅ~24.5-27 25.90 (mode) Quercus variabilis 31.20 (mode) Quercus-D 29-29.5 Å~ 32-34 29.60 (mode) QLuercus acutissima 36.oo (mode) 29 Å~ 37.5-39 29.60 (mode) Quercus aliena ?
Fagus japonica 29 Å~ 31-32.5 Fagus-S
Fagus crenata 39"ro Å~ 45.5--47 39.97Å}O.23 Fagus-L
Fagus hayatae ? Fagus ferruginea ? ? Fagus microcarpa [ ?
the hills in the vicinity ofthe Osaka Area, such as, Senriyama (ITiHARA et aL, 1955; ITiHARA, 1960; 1961, TAKETsuzi and ITiHARA, 1967), Nishinomiya (HuziTA, 1954; ITiHARA et al., 1965), Hirakata (TAKAyA and ITiHARA, 1961), Fukakusa (FuKAKusA REsEARcH GRoup, l962), Senpoku (ITrHARA et al., 1965), Sennan (HARATA et al., 1963), etc. consist mainly of the Osaka group. On the other hand, in the plain region (OsAKA CiTy, 1964; ITiHARA and KAMEi, 1970; ITiHARA, 1970), the Osaka group subsided tectonically and, is overlain by Recent alluvial deposits. The main components of the group are gravels, sands and clays of fresh-water in which ten layers or more of tuff are intercalated as good key beds. Furthermore, a large number of plant remains have also been found in the group. The Osaka group is divided into the upper and the lower parts by the charac- teristic tuff layer called the "Azuki" tuff. In the hilly regions are discriminated A Study on the Poilen Stratigraphy of the Osaka Group l29 three marine clay beds in the lower part and six in the upper part. For con- veniences sake in this paper, the marine clay beds are called as MaO, Mal, Ma2,... Ma9 in ascending order and the fresh-water deposits found between the marine beds are called as FrO-1, Frl-2, ..., (TAi, 1966). The standard succession of the Osaka group is established in the Senriyama Hills, and it has been known that the tuff layers and the marine clay beds there provide a good key for the correlation of that succession with the equivalent deposits found in other districts. A part of the Osaka group in the Sennan district yields a large number of Tertiary type plant remains at a certain horizon and this part is regarded to be the Lowermost part of the Osaka group (ITiHARA, I960, 1961). Apart from the hi!ly region, the Osaka group has also been ascertained in the Osaka plain by deep boring (ITiHARA and KAMEi, 1970; OsAKA CiTy, 1964). In the boring cores, tufflayers and marine clay beds which are equivalent to those of the standard stratigraphical succession could be recognized. Although thirteen marine clay beds are found in the boring cores, it is open to doubt whether the deposits above the Ma9, and those below the depth of 700 m belong to the members of the Osaka group or not.
The standard Polten succession On the basis of the pollen analyses, the present writer divided the Osaka group in Fukakusa and Hirakata districts into two zones, i.e., Metaseguoia zone and Fagus zone, and furthermore, into several subzones (TAi, 1964, 1963). In view of the subsequent informations obtained by the pollen analyses of other areas, it becomes necessary to revise the former zonation to some extent. In order to establish the standard pollen succession, the more precise data obtained from the following localities have to be added to the former results. a. Tsuchimaru-Oike (Izumisano City, Osaka Prefecture), (TAi, 1970-a). Lower- most part of the Osaka group (Fig. 2-a). b. Central part of the Senriyama Hills (Toyonaka City and Suita City, Osaka Prefecture), (TAi, 1970-b). Lowermost and lower parts of the Osaka group (from Shimakumayama tuff horizon to Azuki tuff horizon in Ma3) (Fig. 2-b). c. Hirakata Hill (Hirakata City, Osaka Prefecture), (TA:, 1963, 1964), The lower and the upper parts of the Osaka group. (Ma2-Ma8) (Fig. 2-b). d. Machikaneyama, north-western part of the Senriyama Hills. (Toyonaka ' City, Osaka Prefecture), (TAi, 1969). The upper part of the Osaka group. (Ma7-Ma9) (Fig. 2-b). From the view point of the pollen succession, the Osaka group in the hilly regions can be subdivided into eight subzones, i.e., A,B,...,H, in ascending order. For the zonal classification the disappearance of the Tertiary type tree pollen and the characteristics of the pollen assemblage in each horizon were available 130 Akiko TAi as criteria. In higher category, the A- to the D subzones are lumped collectively in the Metaseguoia zone, and the E- to the H subzones in the Fagus zone. Metaseguoia zone: Taxodiaceae I-a (of which the distribution is characterized by predominance of Metaseguoia) and I-b (the frequency distribution curve indicates the polien grain size represented by mixture of Metaseguoia and other species of Taxodiaceae) are found consistently. The boundary between the Metaseeuoia and Fagus zones is recongnized at the base of the Ma3 in the Senriyama Hills. A subzone: This subzone includes the Osaka group at Tsuchimaru-Oike, and ranges stratigraphically up to the Shimakumayama tuff in the Senriyama Hills. The tree pollen of the Tertiary type, especially those of Ginkgo, Keteleeria, Liquidambar and Pseudolarix (?), are present consistently, and Alangium (?) is found only in this
[ 1] marine clay iO,¥,S:g.' sands with pebble or granule [[IIIIII] fresh water clay Eiiiil] tuff
/.L'i-I'l¥i. silt EiiiliS coaly clay or ligriite sands
o ffill/-ff'ng/g TSUCHIMARU eD" fi MOH v R Coniferous Broad leaved e ca : trees trees ? d ev H --- -- v --- t bev :eo: or + igg¥ xx.$ Is'ij.
? ¥.-¥.;lb¥.'i.' 9 ? # - epo 1 I4m t ' sl ' ll ill ' lt ' ll ltt l tt lll t lt 1 iitt t l- A TANNOWA 1 t l ' '
/tt' tt ttt tttt ;tt :t tt tt II t.t tt tt i tttt ' t tt. tt ttt :tttttt /ttt 'tttt I ttt / . tt s#
Members - of tr.O .ot. O o .8t. Tertiary type pollen 8- oo eX"
Fig. 2-a. Tsuchimaru-oike and Tannowa, FAGUSZONE METASEQUOIAZONE = o Cr., l:1 A Q an < ! ! Tsuga-K ---.------.------M-.Menyanthes -.-- -}E- -E- ! ! l Tsuga-D or SD
, < ul gl i il.l g!
g t Y .tti, l ts"l ""l B1 t.H < . o 81 i.H5 .6I :l ¥l-) I =! zili or o 't(il q t[sl " ' o l 5 g.i E-i - Qi vq k¥l a .- i llil1111 lllTI[ cr) 11t!lllllllilillll II ootlvllllSllgotlllllllll s = illil iii Dl c" eDO x¥g vo ee ll E p ll oOo i .o2 Otie Oe .E!. l l ! oo III Oe Qeo 1lhh-i lo.o il1osi i Lagerstroemia Quercus .- o. Pseudolarix? -N-L+L+ -ee-e---Å~+----voctocarp [g g] NO-.s Å~ ss-- . Å~ Å~Å~ K)-- oo------ooo- -Å~ -oc-e--o- Å~ Å~ ~ Å~ Å~Å~ Pinus.-' / Å~- Pinus Å~ xx Å~-oe-- --- ~ Alnus Å~Å~-D--Å~-e-:. ~ ETertiary type pollen + + +++ < v "Å~"8 -E g8"xo-coos ge8 '- < g&tg*c:.mop ut se > - EP$ 1 - g - . Fig. 2-b. Senriyama Hills and Hirakata Hill, A Study on the Poilen Stratigraphy of the Osaka Group 131 FUKAKUSA ;'¥l//-t'-!¥-.¥1 t-t-t ttt ltl/t./tt ' =Ma6 .tt ttt >t1 1/11.fiI''''' t11t ¥/1//1////11/ '/""'lt'1""/''1'/"'' tt F tttt mb Ma5 = tt tttttttt tt tt tt tt lttt/tttt ' oti o '.el.' 'e' '.e ¥ft¥ /t- a 'e.' /ttt /t tl///t = tt ., 1,,.-.. 1.,/¥/.t.¥.//../ a /. l/t./tttttttt- m tt i,,I/ /tt/t/t/tlt/t.ltt/tttttt.ttttttttttt.tt.t/ttttt- .tt /s/,///,¥ ,1//////¥ Ma4 --,. m ,t.1/... t/t.ttt ' ttt ltttt .tt N e¥ ,10... /1'1 e' tt E tt /t.t ttt O tt tl' ¥I¥¥.'¥1¥i¥1 Azukituffee 8 Z ttt lr1 v oR-a -tpttmt//'1111"¥111/11¥i'/1/il¥'1¥11¥i.'/.11111.li/.1¥1¥1,¥l/'.l,,.,1,..tttt.tttttttttttttttttt.ttt:tttt +t- ii¥¥.,... ,,.ts-¥¥¥---.,¥¥---/ ' ttt /t Ma3 /ttt ttltt /ttttttt 'I.. t¥//sll tt ttt tt o l.i.Iii ttt pt tt ttt ttt tt : o' obeti t g .i,,//'/i,/1:':i..1./I/:,.:;i; t:) :ss/i'.1¥/=1../....,..t"tt/"'/i 1:. /:, .1•,•fiÅ}ltÅ},11i/'•:/•i/::I i :1:/,/:,,1./.,./.....,.- -, :.¥ s 'ttt-.-:Mr )Sb - tt t.t .t : ttt ff:"' l:'1/::::/¥ii¥/::1/1:¥11/111//-¥1/1//lili:11It-11iill / 7=T=LT' t/ m "'/'/'/''//1//''i"1""'/1"//il'/"""'""':/'/'11'' "m t.t .1/1/1¥111 tt t/ rmm tttt l-.t#-'i' Åëo .t. /., l' I¥.'.'ttt. //,..1-.,///1-,1.11//111,/./-,...... , ttt tt D Pink ... -. ,. p /ttlt/.t/tltttttt/tttt.11tt/.t/tttttt./tt/ttlt/t 1 tttt t//tt O tuff t-- ttttttt : N ? : > ./ /t/ltt./ttt /tltttttt/tttltlttttttltttt...//tttt ttt : . l tttt /¥,.-¥¥,¥. , t/tttttt./t.ttttttt- lt"/t'lttt titttttttt -t .t 1tr i5'il=t)5:1g,i :Nxxx :x Isni :x oZmN :x pt : Bi , Fig.2-c. Fukakusa. Fig. 2. Principal pollen profile of the Osaka group in hilly region. "Note" Method of counting: i) As to the cardinal number of the main tree pollen, the following types such as Pinus, Ainzas, Saiix, Cupressaceae-Taxaceae type, cf. Zeikova and Tertiary type are kept apart from the basic sum. ii) The cardinal number of the excluded pollen is the sum of the number of the main tree pollen and the excluded pollen. P.L.: Psetedotsuga-Larix type pollen 132 Akiko TAi subzone. The percentage is low for Taxodiaceae type pollen (occurring in as- sociation with Gtlptostrobus (?)'), and high for Qaercus-D, D-E and E and Fagus S. The Picea pollen percentage (A type) increases near the upper limit of A subzone, and the first appearance of Men!anthes is characteristic. B subzone : This subzone ranges stratigraphically from above the upper boundary of A subzone to the horizon above the top of the Senriyama tuff in the Senriyama Hills. With the exception of Picea A and Taxodiaceae I-a type pollen, the per- centage is remarkably low for the Tertiary type tree pollen; Keteleeria is entirely absent. Pseudolarix (?) continues to this subzone. Zelkova-Ulmtts is present con- sistently and, with a few exceptions, the percentage is low for Fagus and Quercus, C subzone: This subzone ranges stratigraphically from above the upper limit of the B subzone to the Upper Yellow tuff in the Senriyama Hills. Comparing with other subzones, this subzone is characterized by the constant presence of Taxodiaceae I-a type pollen, the higher percentage for Querctts D-E and -E than for Fagus. Ginkgo continues to this subzone and Lieuidambar is sparsely found. D subzone: This subzone ranges stratigraphically from above the upper bounda- ry of the C subzone to the lower boundary of Ma3 in the Senriyama Hills. Taxo- diaceae type pollen changes from I-a to I-b, and finally, it becomes to show a distribution pattern similar to that of II type, at the horizon above the Ma2. It is also characteristic of this $ubzone that such coniferous tree pollen as Tsuga, Sct'adopitys and Picea B (partly including Picea A) show high percentage in the fresh-water beds, while the spectrum showing high pollen percentage for Pinus is found in the marine beds. Although such difference of the pollen spectrum corresponds with the difference of the sedimentary facies, it is noticeable that, in the non-marine bed (Fr 2-3) below the Ma3 in the Hirakata Hills, the coniferous trees like as Picea, Tsuga D-S and Haploxylon type Pintts show high pollen per- centage. Fagus zone: This zone ranges from above the upper limit of the Metaseguoia zone to Ma9 in the Machikaneyama. This zone is characterized by high percentage of Fagtts polien in marine beds. E subzone: This subzone ranges stratigraphically from the base of the Fagus zone to the upper limit of the Ma4 in the Hirakata Hills. In this subzone, it is characteristic that Fagus, Quercus E and D-E and SciadoPitys are always present consistently in marine beds. In the lower parts of both the Ma3 and the Ma4, Tsuga S-D and Quercus-D are found. F subzone: This subzone ranges from above the upper limit of the E subzone to the base of Ma7 at Machikaneyama. The spectra which show high pollen percentage for such coniferous trees as Picea B, Tsuga D and D-S and Hapioxylon * The pollen has characteristics similar to those ofliving GIJPtestrobus pollen (YAMAzAKi and TAKEoKA, 1956). AStudy on the Pollen Stratigraphy of the Osaka Group r33 type Pinus are found in fresh-water beds (Fr 4-5 and Fr 6-7), and Larix and Menlanthes are also present. In marine beds, the pollen percentage becomes lower for Quercus and higher for Fagus. In Ma5 bed, however, the pollen percentage becomes gradually higher from Fagus to Picea (including Picea Polita?) and in Ma6 bed Taxodiaceae II type and Tsuga S show a high pollen percentage. G subzone: This subzone ranges stratigraphically from the base of the Ma7 to the upper limit of Ma8 at Machikaneyama. The subzone is characterized by the fact that pollen percentage becomes higher for Fagus S and Taxodiaceae II type (in marine beds), and that in the lower part of the Ma7 and Ma8 such tree pollen as PodocarPus, Lagerstroemia and Paliurus are present. The pollen of Fagus increases in size at the base of Ma7 and the upper limit of Ma8. Men"anthes is also present at the base of Ma7. H subzone: This subzone corresponds to Ma9 in Machikaneyama. Compared with G subzone, the pollen of Fagtts in this subzone increases in size (L type), and the type of Tsttga changes from Tsuga S to Tsuga S-D at the upper part of Ma9. IV. Correlation between the other area of Osaka Group and the standard pollen succession DeeP drilling core and standard Pollen succession On the basis of pollen analyses, the stratigraphical section of the deep bore hole, OD-1 (Minato-Ku, Osaka City) has been divided into the following zones (TAi, 1966) (Fig. 3). 1) The boring core section is divided into lower and upper parts, i.e., Metaseguoia and Fagus zones at the base of Ma3 (at the depth of 413m). 2) The Metaseguoia zone is subdivided into two parts, i.e., the upper and the lower Metaseeuoia subzones at the upper limit of MaO. The lower Iimit of the lower Metasequoia subzone corresponds with the boundary (about 700 m in depth) between III-b and IV beds of Ikebe's stratigraphy (OsAKA CiTy, 1964). 3) At the present time, the upper limit of the Fagus zone is indeterminable. The section ranging from the MaO to Ma9 in the OD-1 core can be correlated stratigraphically with the standard pollen succession. The upper Metasegecoia subzone is correlated to D subzone in the standard pollen succession. The Fagus zone in OD-1 core is subdivided into four subzones, i.e., E, F, G and H subzones. The pollen percentage in each zone of OD-1 core is comparable to that of the standard pollen succession. With the exception ofthe Fr 6-7, the samples for pollen analysis were taken from every horizon of fresh-water beds between marine beds. Accordingly, the result of the analysis is useful in supplementing the missing parts of the pollen diagram in the standard pollen succession. In marine beds, the pattern of the appearance of the tree pollen is rather similar to that of the standard pollen succession. 134 Akiko TA[ In Fr 34 of E subzone, Tsuga S-D occurs in association with Fagus, Quectts D and Taxodiaceae II type pollen. In Ma6 ofF subzone, Fagus is dominant in its lower part and SciadoPit2s in its upper part. Namely, the pollen assemblage differs from that of the standard pollen succession in which Taxodiaceae type II polien and Tsuga are dominant. In the Fr 4-5 and the Fr 5-6, coniferous trees such as Tsuga S-D, Tsuga D, Picea and Haploxylon type Pinus, are dominant and Menlanthes occurs partly. The percentage is high for Taxodiaceae II type pollen in Ma8 of G subzone. Tsuga S-D occurs in association with the Taxodiaceae type pollen in Fr 7-8 and in the upper part of Ma8. In the fresh-water bed overlying Ma8 ofH subzone, Picea becomes predominant in association with Tsuga S-D. In the lower part of Ma9, Fagus L is predominant and the pollen assemblage is similar to that of the standard pollen succession. In the middle and the upper parts of Ma9, however, the pollen percentage is high for SciadoPit"s and Tsuga (S type, S-D type and K type) and Iow for broad-leaved trees. A horizon near the boundary (about 700m in depth) between III-b and IV beds yields high percentage of Picea and Pinus. Judging from the pattern of the distribution of grain size, Picea of this horizon can be identified as an inter- mediate type between the A and the B types (Fig. 8-b) . The spectrum corresponding with this horizon is absent in the standard po]len succession. Thefreguenc2 distribution of the Pollen in the dePosits below the depth of 700 m (IV bed) Tertiary type pollen, such as Keteleeria, Pseudolarix (?), Ginkgo and Liguidambar, are sparsely found. In general, the percentage of them rises slightly toward the lower part. Of the Tertiary type pollen, Pseudolarix (?) shows comparatively high percentage and Lieuidambar occurs only near the lower boundary. Coniferous trees, such as Taxodiaceae type pollen and Picea, show higher pollen percentage than that of B subzone of the standard pollen succession. Quercus (including E type) and Fagus are present consistently. As a whole, however, the pollen as- semblage has many similarities to that of the B subzone of the standard pollen successlon. ' Keteleeria is comparatively consistent in the deposits below the depth of 880 m, and Taxodiaceae type pollen found in the lower ]imit has the distribution pattern ofl-b type. In general, the tree pollen assemblage are similar to those ofA subzone of the standard pollen succession. Potlen succession in Fukakusa and Tannowa (1) Fukakusa (Fushimi-ku Kyoto City), (TAi, 1963): It is known that the Osaka group in this district ranges from the horizon of the fresh-water clay bed lying 5-6 m below the Pink tuff to the horizon of Ma6. uo IA D Q ". co¥<"¥ 1 l l l ll. ol . IN l 1-l osl ll ItuI IN,E :i lx ! -XrMA- l 1 - m l ll "-o--- 11 ll "---O--' Il -M- -M- -=- -M- Taxodiaceae(gkt:ba] ll o l 1 l 11 pza=Q I -.--J---Liquidambar I --- 1 -L"- pt--- " "rv " Ginkgoi pt--.--"--- o l ------>ts= l l .:esa'tl l1 "Pseudolarix(?)e-tu- L i ,1 1 ! " " l -¥ 1 ! Keteleeria o 1 I 1 i ll T "-. ------".-.------" " - '1 -" l ll i1 +--' Quercus 1 l x 1l ll + ll l ---.Pinus' (Å~ Haploxylon type) 1 l . ll Alnus Tertiary type po11en l(Keteleeria+Pseudolarix(?)+Ginkgo+Liquidambar) + E>" 1 T.cao.vca'gop=':t k e- g .tube gy " !lg¥as?i,,.., N N " < . - . ' ' . i . . ,1goE"i.j'g."/9/11 . . ' 1 . x . . ,Å~" .' g k "E N 11 9 e di -e : o e o e Oeo . o e eO Oo Oo oe o "o za o o ooo e oeoOo o e oe Oo Oe s o g o o oOOOo oe Eo n ts n oco Dco 8 ". ts ". = A. o i:h, m A l l i l 1 ! l l l CX1II 1 l:lll l -o ll l co I pt t I l ve t 1 1l il orl l lIn tu 1 illl"l as l lco 1l l I-1 t l :os l lSl il 1 :es l Menyanthes es l -E- EI I IS ll Ol I: l l: l 1:l l 1osE -E-} 1 I ll Ei l l l l l II ll Tsuga11 Ki 1 : l ' ll II l l -eFLo-}- .ditX-+-l-5=- Tsuga S-D or TsugaD -cF ll l l -M--M-F 1II -X' l ll ll as -ee-e-o--eF -M--M- 1 I -oo-e- ! I ll -M- l 1 l --O- -Kpt1 , 1 Quercus bui l+l ll ww ll l Å~-Å~ l l I ou I -O--O- l l it/ i 1 -o- -o- -O--C--O-1 -O-1 11 l tt,,tti l lt 11 oE 1 l I 11 I l-!l l I ! l Å~Å~ t !l ll iXt l •Å~ ! Å~- ll l Å~ lt ttx l t OD 1 1 l1I I IX, .Å~ 1 ' l Pinus l l 1 1 il l li j 111 ll l 1 1-X l l ' -i--T 1 II 1 l y l lli I l l l / Alnus 1 1 N bXV T v'?'S'.IiVlNlEilanj . 8 . ,--- L - $ . . . . . ' 8 goÅëitsly-1'-:`OlOl ...... u.) -. ' E -+ i . $ ` "x" J II 8 - ee e . eee ee . eeeeeeevea Oeeeeee o o aeb eeeeeeeeeeeeeeo Op eD e eeeeeeo oOoO o boeO " 8 -- fi -O .nO Eo oA . . E g e x Fig. 3. ?rincipal pellen proMe of the deep broing core, (OD-1> in Osaka CEty. A Study on the Pollen Stratigraphy of the Osaka Group 135 The Metaseguoia zone in Fukakusa, with the exception of its lower limit, can be correlated stratigraphically and palynologically with the D subzone of the standard pollen succession. Namely, Taxodiaceae type pollen is made of the I-b type, and the Tertiary elements have already vanished with the exception of Taxodiaceae type pollen and Picea A, and the broad leaved trees, such as FagtLs and Quercus, are found rather frequently. In the lowermost part of this zone, the Tertiary type pollen are more abundant than in the overlying part. The pollen spectrum of the lowermost part indicates that Taxodiaceae type pollen !'s distributed in a pattern similar to that of I-a type, and Lieuidambar is also present in this part. The po]len composition indicates that the aassemblage is very similar to that of D subzone of the standard pollen successlon, The Fagzts zone is characterized by the fact that the pollen percentage for Fagus is high in four marine clay beds. The frequency distribution ofpollen, such as that of Fagus, Querons and Picea, in these four marine clay beds corresponds to the pollen assemblage of each subzone of the standard pollen succession. In the Ma6, the percentage is low for Taxodiaceae type II and Tsuga, while it is high for Fa.gtts. (2) Tannowa (Sennan-Gun, Osaka Prefecture)(TAi and UENo, 1965): The Osaka group found i,n Tannowa is regardcd to be one of the lowermost member of the group, but it has not been ascertained whether it corresponds with the group in the Tsuchimaru-Oike. In the pollen assemblage, Keteleeria, Pseudolarix (?¥ ) and Liguidambar are present. The pollen percentage is low for Taxodiaceae type pollen and is higher for Querctts D and D-E than for Fagtcs. The pollen assemblage has characteristics similar to those of the A subzone in the standard pollen succession and of the lowermost part of OD-1 cores. V. Pollen flora from the beds bearing the plant remains Pollen from the beds which ]ield the cold tyPe Plant remains It has been known that the plant remains suggesting the cold climate were yielded from the Osaka group in Gokenya, Manzidani, Komyo-ike and Toyonaka. The horizons of those plant remains are directly below the Ma3 (Gokenya, ITiHARA, 1960, 1961) and also just below Ma7 (Manzidani and Komyo-ike, Ii[HARA et al., 1965). As for the remains from Toyonaka, the stratigraphical position and the details have not yet been clarified, but according ro S. IsHiDA (personal information), the horizon is regarded to be Ma8 or Ma9. The sampling horizons and percentage of main tree pollen of those districts are given in Fig. 4, and the percentage of the other pollen'and spore is also given in Table 2. l36 Akiko TAi c) l - :. E i o 7 > m zN- x o 1.¥'L¥lb.. t-1....t ¥/tis,,'ii.F¥l.. ll¥b¥ -.. li li /S¥i¥iliiitt ¥,P'! l' !i! il"ilii!i!ili ilil -. .i..t. !i!. li:¥s,t' .' t- ttt K !' i -¥ tt Li .o,¥ !i! /ttt F!iL ¥- 11i,i¥i, x e-. i/ { xxx¥x' e,bi'¥. 'f' o gl-t z.K--.-.--m U> z> x 'e- :¥.!. 'tlttt ' -it¥/1,t,/. x> e >'-tt'x'x'X'N' z-.'x'N .- I -. /... ,/ l// ill¥1 ' v..,/.'v' ill/¥/ 5 l¥:' 1!/¥ //ss-, 's 8 //1 tt/ ll,/i + l'. 1il¥' "x" ¥' {.g- ttt ¥ll,1 {t xNXNXYxX'xx:x.-.d..-.-¥-.¥. ' k. Pinus }ill¥ .t. t.. /,s -tt pa: Couvnon 1ij + ls, lli' lt.' haploxy]on+:Rare i'il' x 'g .tri ttlt Abies -tltt -II 'x ,ac -'¥" 1/}-. -..'-. s.1 "' 1/s -- l-l i" Rbl Picea .x", 'T/ v. ,11¥ t/./ /. tt ... T, .- t).. 1:.. 'tt Tsuga i' $- ' .t. ts, 1{¥l¥ li¥i .i .- ' .-F ' s./1. or ltt¥ .- .t tt t../ Pseudotsuga-Larix ttt t g Taxodiaceae P s." ' t ' ij. . t.. ' "t.. ' Cupressaceae-vTaxaceae 'I.1¥ e + ft ia dopitys .-.-. 8bo Fagus pa"x" - -t-tt Quercus -----+t t---t + + Castanea-Castano is - --- + Betula ------t-t-t + bo lus . + Carpinus ---- t-t-.-. ..-t- + Ulmus-Zelkova ' t-t + + Cf.Zelkova -t-t-- . -t Jnglans + + ' t- Merocarya ' t------+ tt + Tilia t-- + + Salix ' -t + + Fraxinus --t Alnus o: 8 8' 8 ; " : .H s' /,M -- "- Mt- -J ts pNO e : if a Fig . 4. Pollen diagram of beds containing the cold type plant remains. A Study on the Pollen Stratigraphy of the Osaka Group 137 Table 2. Parcentages of pollen and spores which are excluded from the pollen diagrams of Fig. 4. Xx.. "x... Localities & Gokenya Manzidani Toyonaka Sample No. Species ..- Å~ Go-1 Go-2 Man-4 -6 -7 To-10 -9 -8 -7 -6 -5 -2 -1 Ilex 2.0 O.3 O.4 O.6 O.3 1.0 O.3 2.1 2.9 Ll Symplocos O.3 O.3 O.5 Lonicela 1.3 O.2 Elaeagnus 1 O.2 / 1 Ericaceae 1.2 O.8 1.3 Rhus O.3 L i Ligustrum? O.4 L O.5 1.4 O.8 O.4 O.2 ! F Buxus I O.3 I Compositae (w. Iong spin) O.4 1.4 2.9 2.0 1.3 i O.4 O.3 1.9 2.3 O.3 l I O.3 O.3 O.1 Taraxacum type i Artemisia O.4 1.4 1 Caryophyllaceae I 3.6 1.6 1.8 O.3 1.6 Umbelliferae O.4 O.4 O,3 l.4 L i I Patrinia I O.4 I i Chenopodium : O.4 O.3 Lilium i Gramineae 27.5 6.4 4.8 2.5 5.9 1,1 2.3 6.2 7.2 6.0 6.0 4.3 4.0 Cyperaceae 6.1 3.0 O.4 3.3 O.3 1.0 O.3 O.2 O.6 Persicarya 1 1 O.4 O.3 O.3 O.5 O.2 1 : Nuphar E I Myriophyllum? O.3 : O.3 1.9 O.3 O.4 O.3 O.3 Menyanthes 1 / 3 colpate l 4.8 1.7 9.8 1.7 6.0 2.0 1.6 O.3 1.3 O.3 O.4 3.3 A 3 colporate 1.0 4.0 1.1 1.2 4.7 4.0 3.9 4.3 O.3 O.5 O.5 O.7 2-5 porate 1.0 1.7 1.0 Forate 1.0 O.8 Inaperturate-Monoporate 9.5 6.6 5.5 9.4 7.5 3.3 4.3 3.6 4.0 8.3 4.2 5.2 10.5 [ Osmunda 1.1 O.9 O.8 O.6 Lycopodium 1 O.1 O.1 Selaginella? O.2 i O.3 1 1.3 O.8 Trilete indet 1 1.3 3.0 O.6 O.9 Ll O.8 17.4 5.5 Monolete indet 83.5 O.6 8.0 5.0 8.3 Ll 1.6 2.1 2.2 27.1 Ll 1.7 4.5 Sphagnum O.2 3.2 2.7 2.2 O.9 7.5 2.0 Total number of ponen & 646 316 299 462 339 371 313 398 361 437 392 770 1OO1 spores ' 138 Akiko TAi (1) Gokenya (Tondabayashi City, Osaka Prefecture): Two samples have been examined. From the upper lignite layer, the occurrence of such plant remains as Menlanthes trtifoliata, Alnus and Picea has been reported. The pollen spectra show that the pollen percentage is low for broad leaved trees and high for coniferous trees and herbs. Ofthe coniferous trees, Picea shows the highest pollen percentage and Pinus (inc!uding Haploxylon type) shows com- paratively low pollen percentage, and Sciadopit2s is absent. Of the broad leaved trees, Alnus shows comparatively high percentage, and Cor]lus, Betuta, Querctas, Fagus, and Ju.glans are sparsely found. Of the herbs, spore and Gramineae show high percentage. In the samples from the lower horizon, spore (Monolete type, ofwhich perin dropped out) shows the highest percentage. The pollen assemblage is simple and the kinds oftree pollen are limited. A small amount ofTaxodiaceae type pollen is present. In the sample from the uppre horizon (}ignite layer), Tsu,ga S type (see Fig. 8-a), Abies, Cupressaseae-Taxaceae type pollen and Pseudotsuga show relatively high pollen percentage and broad leaved trees and herbs increase in number of kinds. SPhagnum spore shows higher percentage in the upper horizon than in the lower horizon, and Men7anthes is also present. (2) Manzidani (Koyoen, Nishinomiya City, Hyogo Prefecture): Plant remains found in the deposits and their corresponding fossil pollen are given in Table 3. Pintts (including Haploxylon type) shows the highest pollen percentage and the percentage for Picea and Tsuga is subordinate to the former. With the exception of the samples from the lower horizon, Tsuga has the distribution pattern of the D type (see Fig. 8¥-a). Abies is present in low percentage throughout the samples. Of the broad leaved trees, Alntts, Betula and Corllzts show relatively high pollen percentages, and Quercus is also present in all the samples, though the pollen per- centage is low. Of the herbs, Gramineae and SPhagnum are present in all the samples, and Menyanthes is also present in several samples. (3) Komyo-ike (Izumi City, Osaka Prefecture): From the lower lignite layer, Menlanthes was reported (ITiHARA et al., 19. 65). As far as two samples have been examined, Taxodiaceae type pollen shows high pollen percentage, and with the exception of Alnus, the broad leaved trees show low pollen percentage. Of the herbs, Gramineae and monolete type spores are frequent. The distribution pattern of Tsttga is D type or D-E type (see Fig. 8-a), and Men.vanthes is also present in the two samples. (4) Toyonaka (Toyonaka City, Osaka Prefecture): From the uppermost part of the upper marine clay bed in Toyonaka, a large number of cones of Picea maximowiczii were found. The pollen diagram shows an irregular frequency A Study on the Pollen Stratigraphy of the Osaka Group 139 Table 3. Plant remains and pollen yiclded from the Manzidani Conifer bed. Mega plant remains Po]len Species Miki Kokawa Arnount Pollen type Abies firma + + Abies Abies homolepis l + R Abies veitchii + Piceajezoensis var. hondoensis + A Picea (B) Picea bicolor + + Picea maximowiczii + + Pinus koraiensis + + A Pinus haploxylon Chamaecyparispsifera ¥ + + R Cpressaceae-Taxaceae Thuja protojaponica + + R Cpressaceae-Taxaceae Pseudotsuga-Larix Larix ginelini + + R (include Larix type) Tsuga ob!onga + ? Tsuga sieboldii + c Tsuga S Tsuga diversifolia c Tsuga D Betula platyphylla + + C Betula Prunus salicipa + + Prunus Prunus maximowiczii + Acer miyabei + Acer Alnus tinctoria + A Alnus Potamogeton pectinatus + - Potamogeton Nuphar akasiensis + Nuphar Ceratophyllum demersum + ? ? Ceratophyllum submersum Menyanthes trifoliata R Menyanthes Corylus heterophyra + + c Corylus distribution and the kind ofpoilen which shows high pollen percentage is different from sample to sample. The tree pollen ofhigh percentage changes in the following sequence in ascending order. 1. Taxodiaceae type, Tsuga--s2. Fagtcs LA3. Picea--s4. Taxodiaceae type-s5. Taxodiaceae type, Cupressaseae-Taxaceae type, Picea. SciadoPitls ranges up to Horizon 1 cited above, and the broad leaved trees show 140 Akiko TAi Table 4. Paercentages of pollen and spores which are excluded from the pollen diagrams of Locality Komyo-ike Pollen & Sample number (Ko.) Spore types i lo 9 7 6 5 4L 4U 3 2 1 Ericaseae ! O,4 1 Styrax 1 O.3 ! Ilex 1 O.6 15 O.4 2.9 2.1 1.2 1.8 ! Symplocos 1 O.4 O.9 O.6 O.4 O.6 Lonicela O.8 3.5 O.3 O.8 O.4 Elaeagnus l O.3 l Rhus 1 O.3 ! E Sapium 1 t 1 Cornus 1 O.3 Ligtistrum? O.5 O.3 1.3 1.4 O.3 O.4 O.4 O.6 i 1 Ludwigia 1 i Vitis O.1 Compositae (w. Iong sp.) O.9 1.0 7.4 2.0 1.2 O.8 O.3 I Compositae (Taraxacum type) O.3 O.3 O.3 O.8 O.3 Ll Artem.isia i O.3 O.5 O.4 Scabiosa O.1 O.2 O.6 O.4 Caryophyllaceae i Umbelliferae O,7 O.5 O.3 i 1 Chenopodium I 1 Kochia? O.3 [ Lilium F Gramineae 6.8 4.1 4.8 38.3 3.7 3.1 2.0 2.2 2.6 3.2 Cyperaceae 4.7 1.9 O.3 1.7 1.2 1.4 1.6 2.6 Persicarya 1.0 O.3 O.1 O.6 O.6 O.8 O.7 O.6 Typha-Sparganium type Ne!umbo : Trapa Nuphar 1.0 [1 Myriophyllum? O.3 I Menyanthes 1.0 4.4 O.3 l 3 colpate 1.3 1.5 1.8 3.7 O.9 1.2 O.7 2.3 2.3 3 colporate 1.3 1.7 2.7 O.5 O.6 O.3 2.4 2.5 O.6 1.7 2-5 porate O,1 O.4 O.3 O.3 Forate O.4 O.3 O.3 O.4 Inaperturate-Monoporate 19.9 19.7 9.7 15.1 7.1 1.8 3.6 3.6 7.1 O.7 Osmunda O.3 Ll O.5 1.7 O.4 O.3 Lycopodium O.3 Trilete 2.7 1.6 6.4 2.3 O.6 O.8 1.7 1.8 1.3 Monopolete ILI 4.7 9.0 5.5 2.3 2.1 i.2 2.8 2.8 6.0 Sphagnum O.7 Total number of 790 394 -848 355 337 259 291 326 372 pollen & spores "8 1 lower -X -- upper XKasuri tuff horizon A Study on the Pollen Stratigraphy of the Osaka Group 141 Fig. 5. l Imakuma i Hirakata Fukui Mitsuike 1 2 6 7 5 26 1 345O.3 023 O.7 l O.4 3.9 1.7 1.3 2.7 O.8 O.4 O.3 O.2 O.6 O.3 O.3 O.7 O.7 3.0 O.4 O.3 e.3 O.3 'O.4 O.3 O.3 O.3 O.3 O.4 O.4 O.2 O.3 1.3 O.5 O.3 3.0 O.2 1.5 O.8 1.0 O.3 O.3 O.2 O.3 O.2 O.3 O.3 O.2 O.2 O.3 O.3 O.2 O.3 O.3 O.3 O.4 I O.4 O.9 4.5 1.7 1.8 3.4 2.2 1.6 6.0 6.6 2.7 3 7 3.8 16.7 1 1.0 1.4 O.9 4.9 O.8 O.8 1.3 O.8 1.5 O.3 3.1 O.3 O.5 O.4 O.6 O.6 O.6 O.3 O.8 O.3 O.3 5.3 3.7 3.2 O.6 1.4 1.0 O.3 25.9 1.5 2.3 1.3 Ll 1.3 2.7 O.5 1.0 18.3 O.17 O.6 O.6 ls17 O.3 O.5 O.3 O.4 O.3 O.6 14.8 5.6 3.7 4.2 2.2 15.6 3.6 1.1 5.6 3.9 6.1 4.2 O.3 O.3 O.7 O.7 O.4 O.7 O.6 O.4 1 O.4 O.3 O.3 0.S O.8 1.1 1.1 O.3 O.8 3.0 Ll 6.3 O.4 1.5 O.6 O.7 O.7 5.3 42 1.6 O.4 2.5 4.3 46.8 O.6 16.8 I I 1 I l 1 t f 266 284 361 303 284 339 385 S96 272 313 517 229 285 628 1 1 1 1 Xt Xl Xl Xt 142 Akiko TAi higher pollen percentage in the lower horizon. Tsuga assumed to be the S type in the lower horizon changes to D or D-S type in the upper horizon (see Fig. 8-a). Fagus shows L type distribution (see Fig. 8-c). In almost all of the samples, especially in the samples from the upper horizon, Alnus shows high pollen percentage. Sphagnum is also frequent in the samples from the upper horizon. Menyanthes is present in Horizon 4. Polten .17ora from S7aygium bed and Kasuri tuff horizon It has been known that the lower part of Ma8 yielded warmth-loving plant remains like as Svaygium, QLuercus (C"clobalanoPsis), etc. (MiKi et al., 1957; KoKAwA, 1959; TAKAyA and ITiHARA, 1961j ITiHARA et al., 1965). In order to examine the pollen assemblages above and below that horizon, the samples were taken from the following localities. Komyo-ike (Izumi City, Osaka Prefecture) Imakuma (Sayama-Cho, Minami-Kawachi-Gun, Osaka Prefecture) Hirakata (Bussharito, Hirakata City, Osaka Prefecture) Fukui (Ibaragi City, Osaka Prefecture) Mitsuike (Kumanoda, Imakuma City, Osaka Prefecture) Machikaneyama (Toyonaka City, Osaka Prefecture) Sampling horizons and the frequency distributions of the main tree pollen are given in Fig. 5, and the frequency distributions of other pollen and spore are given in Table 4 except for Machikaneyama and Hirakata (Shinkori formation; TAi, 1963) of which distribution is shown in Fig. 2-b. The pollen percentages of Pinzts, Alntts, shrubs and herbs differs with places, and then it is dithcult to grasp general tedency. As for the tree pollen, however, following characteristics can be shown. Haploxylon type Pinus shows a high pollen percentage in most of the samples, and the spectrum in which the percentage is high for Taxodiaceae type pollen is frequent. The percentage of Taxodiaceae type pollen rises at the horizon below the Kasuri tuff at Komyo-ike, while in the other districts it rises at the horizon immediately above the Kasuri tuff. But it is out of doubt that the regional rise of the Taxodiaceae type pollen percentage is observed above the Kasuri tuff horizon. As for other tree pollen, the percentage is high for Fagtts in the upper part of the Ma7 in Hirakata and for Zelkova-Ulmus in the upper part of the Kasuri tuff at Imakuma. The spectrum in which Quercus E shows high pollen percentage is present only in the base of the Ma8 in Hirakata (Compare Fig. 5 with Fig. 2-b). Tsuga, as far as the writer examined, is of Tsuga S type. Fagtts of the larger type is found in the uppermost part of Ma7 at Hirakata and in the horizon above the Kasuri tuffin Fukui, and Fagus ofsmaller type is found in the horizon immediately above the Kasuri tuff in Hirakata (see Fig. 8-c). Accordingly, it is safe to say, es .g., en" o O/ N ¥ve > bo N ies¥,9¥ o =Å~ o mg ed a x co ts¥;, otu en Ao > o b tA:i ut = E z N s Sample ut co: es = N = op eV ec v E .- eSS 8 ut number g,g 3 o eee T s 8 N al as k x x : x ua ts oN -vo b nk ue 8 es -= ,!sz-- 2 -*¥ + N 8'`tg as g6 os pt in o s 6 ac a k KOAAYO1KE pt t + + .9 + +++ ++ . 10 eoth tm NAKUMAbb + +- +" + + .7 ¥i'iI .25. ++- +- .6 , Kasuri-tuff ---- + .5 ii .4 .l-1,' -+ + .3 ; - + o:o m + .2 + - - .1 Zo: TSUIKE Mi ttttt:ttt:t Kasuri-tuff . .1 'n'L .' otteeoeoQO, F Fu UKUI.- :-I-l' . ¥x¥ +- .6 Kasuri-tuff ii"' -=- .. -+- - - m - -- .z 'leeb.`'';l.; ' .Tt- oeo eoee Ma7 de- bO RAKATA t (Butsusharito) F:.1¥=¥ . -li•ÅÄ-, li'l]'i'i:{l'1 Ma8 II, ¥x¥ -J) Iim .e;-t z-ii - :} ili'ttitt Kasuri-tuff . .2 . + -+ 'oi :OO - - - 1:'i:'i'' . x + + + -o z=. O 10 20 an 40 se oo'"o Fig. 5 . PollendiagramoftheKasuri-tuffhorizon. AStudy on the Pollen Stratigraphy of the Osaka Group 143 that pollen spectra which indicate definite warm climate have not been found in and below the Kasuri tuff horizon. VI. Problems on the identification of pollen Size freguenc" distribution As it is diMcult or impossible through palynology alone to provide a good picture of local vegatation, palynological studies usually require the species identi- fication supported by some evidences of mega-fossils. Due to the rather broad distribution of most genera, a direct paleoclimatic interpretation of many spectra is Recently limited. new techniques using size frequency ' distribution of pollen grains have been developed (NAKAMuRA; 1957; 1968; TsuKADA, 1966). In spite of the controversy (SATo; 1965; 1967), the writer adopted one of these techniques, and the data were checked by comparison with abundunt informations on mega-fossils. The results obtained from these two sources so far agreed well with each other, and the size frequency distribution technique used by the writer seems to be valid at least in the case of the Osaka group. Some remarks on the preparation of the size frequency distribution curve and its implication for the results will be introduced as following. Consc'deration on the siae freguenay ' distribution of'fossil Potlen grain Preparation of the frequency curve: Taxodiaceae (probably Crmptomeria), Tsuga and Fagus which were obtained from the samples of the strata ranging from the Ma7 and Ma9 were examined by means of Tai's method (TAi, 1969) : That is, a hundred pollen were counted and measured for each pollen type. Variance of population: Mean value of grain size for Taxodiaceas was calculated for each sample, and termed Mcl, Mc2, ...... , Mcn. Next Thompson's method applied to determine whether the mean values belong to a parent population or not. Two mean values out of thirtytwo were rejected with the 50/. significance level. This shows that even with controlled treatment, swelling or shrinking occurred in different degrees in different cases during the process. After rejecting the two samples, the mean values were found to distribute from 30.49Å}O.58 pa to 34.71Å}O.84pa having a variance of about 100/o of the grand average (where the grand average is: Mc==32.60Å}O.25, Mc=2Mci/n) (TAi, 1969). General tendency of grain size change: Mean values of grain size for Fagus, Tsuga, and Taxodiaceae were calculated in each horizon, with Mff, Mfl and Mcl in horizon 1¥, Mf2, Mt2 and Mc2 in horizon 2 and so on. Then the correlation coeMcients (r) among the three plants were calculated. The result was that the coeMcient (r) ranges from O.55 to O.75 at the significant level of50/. as shownin Fig. 6. This implise that there exists parallel tendency in change of 144 Akiko TAi eN a"8z Fagus S .N Tsuga S Ma7 tower pa rt of Ma7 Ma8bed Ma9 bed N ; 22t 0726 rsO,551 / N:28 Taxodiaceae type upper part of Ma7 tower part ot Ma9 bed Fig. 6. Correlation in grain size of Fagus, Tsttga and Taxodiaceae type pollen. r: Correlation co-eMcient, N: Samplenumber. grain size among the three plants. Stratigraphical fluctuation of corrective mean value of grain size for Fagus, and Tsuga: Corrective mean values of size for Fagus and Tsuga were obtained by the following formula: pfi =, 32.6 Å~ l}ill]I, , p,i = 32.6 Å~ lili Ei, Pfi, Pti: corrective mean values of size for Fagus and Tsuga in each sample. The stratigraphica] fluctuation of the corrective mean value is shown in Fig. 7. Those values for Fagus obtained from Ma9 bed, converge around 40 pt, whereas those from the Iower horizons gather around 35 to 36 Ii. As to the grain size of Tsuga the corrective mean values are about 70 pa in the horizons lower than the middle part Ma9, and become largerin the upper zones. This disnibution tendency is not much different even when the rejected samples are incorporated. In order to improve the grain size analyses, FAEGRi and IvERsEN (1964) pro- posed a method in which standarized grain size can be obtained. NAKAMuRA (1968) has applied a similar technique in his studies of the Pleistocene Betula. The writer believes that these methods must be usefu1 for the future studies of the pollen of the Osaka group. Identi cation ofPollen Tsuga pollen (Fig. 8-a): Plant remains of Tsuga diversiolia. T. sieboldii, T. rotundata, T. oblonga and T. Iongibracteata are reported from the Osaka group. Of these Tsuga sieboldii ranges from the early stage of the deposition of the Osaka group up to the present, and Tsuga diverst:fTolia which is sti11 existing shows its first appearancejust above Ma8 (KiNK: GRoup, 1969). The rest are ail extinct (see Fig. 9). A Study on the Pollen Stratigraphy of the Osaka Group 145 Taxodiaceae Fagus N,. Tsuga C Cryptomeria ) - 2- -- ou2-17 .¥ 1, 1 - e..x ' o- t o-- - e . d-.,e 1'Xk 15¥ -eo . - oe 1 : . -.x.¥ 1 ..¥o e-o : -*- t rc . .o e Ma 9 iO: -¥X.¥ ¥l . l .D i-o 1 -K) .oi 5: Se o).-., ' `E,ii!--li'iE]' CNi 3' -e P.¥- -pt lii,,] o-¥k 2: ts--- l ou 1-30: ke pt I,o. ? - t su¥ : -e- o --- o p E coE 25¥ . : . eo- O.b : . d- .o. il .O Ma 8 20: . - 1 I i¥ - 1 15 :. . -... o - - eo : 10¥ e-o --ei ' : m' .E-.'. t- cal : 1..D-e 5¥ `..o--, -- : -. .1¥--- 8opt-.-o ouw-1 '...;8iro-.- : .-o¥o : "e- ' 'e8q.-o- 5¥ I --. o 6: e- re-... J e--. ou324¥ - . o¥ o.-- ic,, : j¥ e- . i -o 20¥ . - Ip-o .-..o :. --- ou 4-4. o -- 4-2¥ . o- . S"b Ma 73-i6: ; . . -O-d- : . - or : - 1O: ¥l-p 70A . : - 5: 10 35E - I - -*t pa 1¥e ------e .-- o ¥- l KRIOI¥ 1 - t 102¥ . " e : Mode Oita .-h,). u loe. . - : tht 9S'l. cortidence interval 9 .L KNA61. L of the tstirnltc rntnn ct -o ef the each stmptc 62. .e . -. e 62w - ` O :values corrected by . . being normatiied : 1 1¥ - 1--. s- by th" iverage poILen siTe ot 1 2. . Kamioka . Tarodiaceae 2 21¥ h -L¥- e¥ : dita ¥abandantd 2 2 2¥ g. '-'-' lt 24¥ -- . I e- Fig. 7. Stratigraphical distribution of the grain size of pollen. (after TAi, 1969> ' l46 Akiko TAi Tsuga D To-1 z' To-2 To-6 To-8 H?(Toyonaka) To-9 s To-10 Ko-10 F-H. (Komyo-ike) Ko-9 Man-4 F.Fr6-7 (Manzidani) Man-6 Go-2 D.Fr2-3 (Gokenya) oo 70 di) 90it Fig.8-a. Tsuga, A Study on the Pollen Stratigraphy of the Osaka Group 147 Picea tt../ (Toyonaka) .t G-H? .g-,tr"i¥¥..,,,f. Fr6-7 tttlttt '11t.ilneif.'¥;,.lilili','es"s''" (Shinkori)"tr'i ttt tll ttt 'ge"t'`pme"M.,ge.. Fr6-7 /l. F ." (Manzidani) .' Fr4-5 k" tt t. - Fr2-3 OD-1,No.13o Fr2-3 ooII D Fr2-1 Sn3-2 -t Frl-O Sn7-6¥".¥i.' ,di {ixlE¥lllva''L¥" ¥¥ OD-1,No.198 B-vC? OD-1No.199 (OD-1) Msn5-2 '1'/'/t't#t'i/''il''/''/' .IllÅ}. tt1/t /'i'' Fl¥ ltt .. B k/" Msn9-1 ¥¥ 1".x mk/¥,¥'"'/k:/ tl"''tl' ,ll}'1'¥1'g.i 1/fi .t/1;t. Shimakumayama Msn12-3 -t"-¥.v A .ltvr1'x stlll..//,. 80 ee 1oo 110 1ac 1so 140 pt Fig.8-b. Picea, i48 Akiko TAT Size frequency distribution demonstrates that the Tsuga S-type pollen is common throughout all the subzones from A to H subzones, whereas the S-D type and D-type pollen appear above the base ofD subzone. Judging from the pollen and plant remains association, the Tsuga S-type is determined to be Tsuga sieboldii The picture of the Tsuga S-D type and Tsuga D-type pollen is still vague, but again from a comparison with the succession of plant remains, the writer supposes that the S-D type and the D-type pollen represent the predominating Tsuga sieboldii and Tsuga diversi otia floral assemblages respectively. K-type Tsuga pollen may correspond with Tsuga oblonga. Picea pollen (Fig. 8-b): The remains of extinct Picea koribai have been reported from various strata ranging from the lowest part of the Osaka group up to the horizon near the Mal (N'iREi, 1968). Judging from the stratigraphical position, A-type pollen of Picea is most probably to correspond to this extinct species. In the Osaka group the species which appears first among the existing Picea in Japan is Picea maximowicnd, which is found at the very bottom of the Osaka group (KiNKi GRoup, 1969). Otherwise, PiceaPolita and Picea bicolor are found in rather higher horizons as in the lower part of the Osaka group (KiNKi GRoup, 1969; KoKAwA, 1959, 1961) (see Fig. 9.). The modern Picea species are all smaller in pollen grain size than the Picea of A-type (see Table 1) and can be grouped into Picea of B-type. According to UENo (1958), only Picea Polita can be distinguished from the rest of B-type Picea by its morphological character. In Fig. 8-b, the pollen size distribution demonstrates that while D subzone and the horizons above it are characterized by Picea pollen of smaller grain size, B subzone is characterized by Picea A-type pollen of which grain size is larger than 100 ,u. The first appearance of Picea potita (?) is shown in D subzone, which is known also from plant remains. As samples of the OD-1 drilling core yield both Picea A and B-types pollen at a depth ofabout 700 m (Fig. 8-b), the writer assumes that this particular horizon may correspond with the horizon ranging from the B to D subzones of the standard column. Taxodiaceae type pollen: The pollen of Metaseeuoia, Gl2Ptostrobus, Sequoia and Cryptomeria are included in this type. Among them, only the pollen of Meta- sequoia is smaller than 30 pt in diameter. The rest apparently have larger diameter. It is difficult or impossible to discriminate Gl]ptostrobus, Seeuoia and Cr7Ptomeria from one another in either shape or size. The following evidences have become to be known from the association of mega-plant remains in the Osaka group (see Fig. 9). a) In the lowermost part of the Osaka group, Metaseeuoia coexists with Gl)pto- strobzts and Seeuoia. b) Metaseguoia coexists with CrlPtomeria in the lower part of the Osaka group. A Study on the Pollen Stratigraphy of the Osaka Group 149 ragusFagus 't''' Toyonaka H? ,,iiiii,' Ma9 (OD-1No.36) (OD-1No.37) H Ma9 ,/1fi./,11¥x"'I .111ltll/1,, (Machikaneyama (FukuiFu-6) Ma9 Total) -t/,.t I'ke,.., "ap'ws'ifi .ng.l ee (HirakataHi-3) ee-. :,-k¥t','.sxs.:,,x'' ,. ¥l., ,,- ,.t Ma7 (Machikaneyama Ma8 Total) (HirakataHi-O) Imai'".¥.tt- G -s¥ 3040sop Ma7 (OD-1No.65) EMa3 (SenriyamaYa1-2) ' tt '"' i''xttt.'-st' Fr1-2 ..11{-1 tsu.11. DMa1 ill?.t tet' (SenriyamaSn5-i?) liill'/.i."/x., il't/getmtt,ktxtua ,' 1/,ge1./t-- A,,1:1 (TsuchimaruTsu1-4) .l en 40 sep Fig.8-c. Fagus. Fig. 8. Distribution of the size of fossil pollen. 150 Akiko TAi plantremains pol1en MetasequiaZOne FaguszOne LMLutDsARPollentype zone ABCDEFGH G;n!tgobileba Ginkgo o-o-o Podoearpurnag; Podocarpus -o- Abiesim Abieshomolcpis Abiesveitchii Abies o-o-o-o o-@-o-o- e------ XPscudotmignsuhretunda ?--o-----KN) x.¥?tcudottugteondvlocarpa Pseuclottugajaponica o-o-o-o o-o-o-o- X.¥Tsugatotundata Tsugatongibracteata TsugaK?typc XT"tgsoblonga T.sleboldiitype(S) ?-o-o o-o-o-o- Tsugstiebeldli T,diversifetiatypc(D) o-o-o-@ o-o-o-@- Tsugadivtriifelia x¥? o-o-o-o- X.Piceakoriba; Hcca{A) ficesmaxirnowiczH ?o-@-o-o Pioeaboyarnai ¥x? Picea(B) Eoeapelita ptceabico]or Ketcleeritdavidiana Kcte1ecria Ptcudalarirkaemnfcri Pscudotarix{?) Larixgtnclini Larixtypc e-- tt --.. }.... X?inusfujiii Hnusoligo:epis -?---o iPinusdiploxvlon HnusthunbeTgii Enusdcmlflon o-o-@-o nnushnieasts Hnusammndii --- tttt-t Pinushaplexylon finuspentaphylla o-o-o-o Pinuspentaphyllavar.himekomatsu H-- Scindapitysverticillata Sciadopitys -Tttt @-e-o-o Scquoiasempervirens Ta]codiaceacI-b Glvptcttorobuspensilis Metaseguoiadisticha Ta)[odiaceaeI-a Crvptomcrisjaponica TaxodiaccacII Totrcyanuciferz {-oo" .apmotaxusobohata Cephaletvcushaniagtonia CunninghtmiaIinceolata Cunniaghamiakonishi'i Taiwadecryptomcrioidcs ahsrnaecyparisobtusa .? ctzamaecvparisptifcra Cupressaccac-- Tltuiastandishil Ta)taceacIvpc o-o-o-o- 'XThujiprotojtponica JmipcrusrWda Junipcrusconfcrta TltujopsisdolabTata . Ligu{darnhltformosana Liquldamhar Fagusferruginca XFagusrnicrocarpi Fagushtyatat .-...-)' Fsguljtponica FagusS D------O-o-- Fnsuscrenata X=? FagasL ft.ptercmNbroldta ptc!=utsliuca 11Vlmus-zelkovatvpe Cb:ercuseilva Quercusevfrgreen o--¥------o Q!,c.euiphi11ymeeides tvpcCE) Qiercusrerrxts pttrcusyariabiLis Qyet=Ltsacutissimi Qucrcusdccidaous O-ot"-""- QpercLzaslicna typc(D) pterculerispula e-¥¥------{ x.grkho.'"bl,".,ff.rii. o-o-o-o XStpiumxbiferumvar,plcistoccaca Sapium o-o-o-o- x,-Paliurusnipponicus PaLiurus -o- Menyuithestrifo1;ata Mcnyanthes e--e------o------o- A Study on the Pollen Stratigraphy of the Osaka Group 151 c) Metaseguoia is limited below the bottom of Ma2. d) Ctvptomeria is seen continuously throughout the upper part of the Osaka group. Taking the above mentioned evidences into consideration, it may be possible to interpret the palynological data concerning Taxodiaceae as the following: a) Taxodiaceae type pollen associated with Metaseguoia, Gl2Ptostrobus and Seauoia at the lowermost part of the OD-1 core show I-b type floral assemblage. b) Taxodiaceae type pollen associated with dominant Metaseguoia in B to D subzones show I-a type fioral assemblage. c) Taxocliaceae type pollen characterized by the co-existence of Metaseeuoia and C(7Ptomeria in D subzone shows I-b type assemblage. d) Taxodiaceae type pollen associated with dominant C(vPtomeria in E to H subzones shows II type assemblage. Fagtts polien: Plant remains of Fagus ferruginea, F. hayatae, E microcarpa and F. ]'aPonica are reported from the lowermost part of the Osaka group (MiKi; 1948, 1955; MiKi et al., 1962; KiNKi GRoup, 1969). The upper part of the Osaka group yields various species of unidentified Eagus besides F. hayatae and F. microcarpa (FuKAKusA REsEARcH GRoup, 1962; HuziTA, 1954; ITiHATA, 1960; ITmARA, et al., 1955; KiNKi GRoup, l969; MiKi et al,, 1962) (Fig. 9). Size frequency curves reveal that marine clay beds ofA and G subzones yield dominantly Fagus S-type, whereas Fagus in H subzone indicatcs L-type. Fagtcs obtained from a peat bed at Toyonaka (see Fig. 8-c) is identified with L-type. In H subzone, Fagtts L-type is more tolerant of cold climate than Fagas S-type. It is diMcult to determine whether the I7agus L-type corresponds with Fagus crenata or such extinct species as ITagus microcarPa. The stratigraphical correlation between pollen and plant remains is shown in Fig. 9. VII. Transition of forest and climatic change InterPretation of sPectrum In making a deduction from the lists of plant remains it has to be assumed that the past vegetation was related to climate as it is at the present day. It is one of the basic assumptions for reconstructing the past forest. Long distance transport Fig. 9. Stratigraphical correlation of plant remains and pollen. "Note" LM-: Lowermost part of the Osaka group, L: Lower part of the Osaka group, U: Upper part ofthe Osaka group, UM: Uppermost part of the Osaka group, * Extinct species, *? Not yielded from the Osaka group but reported from the corresponding sediments in other region, @: Common. After. K. HuziTA (1954), M. ITiHARA et at. (1955, 1965), M. ITiHARA (1960), 1961), S. KoKAwA (1959, 1961), S. MiKi et al. (1962), H. NiREi (1968, 1969), K. TAKAyA & M. ITiHARA (1961), K. TAKAyA (1963), FuKAKusA REsEARcH GRoup (l962), IBARAGi REsEARaH GRoup (1966), KiNKi REsEARcH GRoup (1969), A. TAi (1963, 1964, 1965, 1966, 1969, 1970a, 1970b). 152 Akiko TAi of pollen by wind and differential productivity of pollen by trees are also highly informative for evaluation of environmental reconstruction. In order to assume the climatic conditions which correspond to the forest type, the writer used cor- relation charts prepared from various sources (Figs. 10 a, b and Table 5). ]Four groups of sPectra and their corresPonding climatic conditions Spectra obtained from the Osaka group can be classified into four groups. Clirnaticzone Northernpartof Southernpartof Coel-temperate warm-temperate Species 14Q180eCm,d,lyear (warmth-index) Loc.Ne. 458 -5--100CmdVy'-'1'O"-10---- ear (coldness-index) ?o.o? -20 -11eN-e-O5 -o,s'--'-'-"O--2O "- -10-5--10e--- o----- -15-5N-5-5"-10 '- 20 Metasequoia5 -11-9e----t glyptostroboides ttttt Glyptostrobus9 pensilis O--O,5O -- --- oo o o-- - Fagushayatae14 O---5O Fig. 10-a. Chart showing the temperature threshold for principal forest in China and Tai- wan, complied from the data ofR. KANEHiRA (1963), Li Hui-LiN (1963) and WANG CHi-Wu (1961), based on the Kira's warmth-index and coldness-index arrangement. Locality number corresponds with that of Table 5. A Study on the Pollen Stratigraphy ofthe Osaka Group 153 Table 5. Table showing the forest type and altit ude ofprincipal forests in China and Taiwan. The data are same as in Fig. 10-a. Locality Forest type Altitude 1. Tienmu-Shan Northern Chekiang mixed mesophytiÅë forest 750m-11oom 2. Hwang-Shan Southern Anhwei }) 450-1500 3. Chiuwa-Shan Southern Anhwei t) iroO- 650 4. Lu-Shan Northern Kiangsi 11 800-1500 5. Shusha-pa western Hupeh deciduous broad-leaved 1OOO-11OO forest 6. Fanching-Shan Eastern Kweichow )t 170a18oo 7. Lungtungkou-Hanchiakou valleys of )s 1300 Wuchuan-Hsien 8. Chenkou Western Hupen-Eastern desiduous broad-leaved- 1200-1600 Szechuan mesophytic forest 9. Taming-Shan Southern Kwangsi mixed mesophytic forest 1000-1700 IO. Wumong-Shan Southwestern Kweichow evergreen broad-leaved lOOO-2000 forest 11. Mon-Shan Southern Hunan 1) 600-1200 I2. : Taiyun-Shan Southern Fukien I el .11OO 13. Kumming Central Yunnan pine forest 1600-2600 14. North Chan-tien Shan (Tabboku) evergreen broad-leaved 1300-1500 Northern Taiwan forest 15. Central part of mountainous area ? 900-2000 in Taiwan 16. Kova-Kei¥Kinkaryo-kei Northern ? 300- 600 Taiwan 17, Krayu Southern Taiwan ? 900 Based on their patterns of plant assemblage the following is a brief description of each group. (1) A group (Tertiary type flora group) A-1 subgroup: This is characterized ' by such Tertiary type plants as Keteleeria, Pseudolarix, Ginkgo, Liguidambar, Gl2Ptostrobus and Seeuoia. Modern Seguoia is distributed along the coastal zones of northwestern North America, and the rest is alive in the mountain regions of South Middle China and Taiwan. The warmth-index* along the northern edge of the native area is around IOOOC m,d. The coldness-index**calculated for Keteleeria and Cl)ptostrobus is OOC m.d., and that for the rest ranges from -100C m.d. to -150C m.d. The climate sug- gested by this subgroup is very similar to that of the northern part of the warm " T. KiRA (1945 a, b) supposing that the physiological zero point of temperature for p]ant is 50C, introduced warmth-index formulated as Z (e-5)OC month degreelyear, where e is average monthly temperature which is higher than 50C. ** Coldness-index is formulated as 2 (5-e')OC month degreelyear, where e' is average monthly temperature whic h is lower than 50C. (T. KiRA, 1948) 154 Akiko TAi Northern part of Southern part Of sub- Polar Coo1-temperate Species Subarctic warm-temperate warm-temperate tropical e 15 45 85 140 1800C m.d.lyear Abies veitchii -- --- Picea jezoensis var, hondoensis ' ------Tsuga diversifolia . - Larix leptolepis ------d- Pinus koraiensis ---- Picea bicolor --- Picea rnaxlmowlczn ------ Pinus pentaphylla , - -- - Abies homolepis ------. Picea polita -- - -- Pinus parviflora . - d-- Tsuga sieboldii ----- . -- d------o Abies firma -d------o Pseudotsuga japonica ------Sciadopitys verticilata . .- - Cryptomeriajaponica ------e Betula ermann Betula platyphylla Fagus crenata Fagusjaponica Quercus crispula Quercus dentata Quercus serrata Castanea pubinervis Carpinus carpinoides Carpinus laxiflora Quercus variabilis Quercus acutissima Quercus myrsinaefolia Quercus stenophylla Quercus acuta Quercus paucidentata Quercus glauca, Quercus gilva Castanopsis cuspidata Zelkova serrata 'r-'' Celtis sinensis var, Japonica Podocarpus nagi Fig. 10 b. Chart showing the temperature threshold for principal forest trees in Central part of Honshu, Japan. "Note" with the exception of coniferous tress, mid-range of threshold temperature for tree is not visible. - - Warm limit of the threshold temperature in Yakushima Island. After T. KiRA (1949), 1954, 1958), T. KiRA & M. YosHiNo (1967), slightly mod- ified by the writer. A Study on the Pollen Stratigraphy of the Osaka Group 155 temperate zone of the present (Fig.10-a). A-2 subgroup: This is characterized by Metaseguoia and Pzcea A. Native area of Metaseguoia occupies the northern edge of the warm temperate zone, but some cultivated Metasequoia forests are seen beyond this limit (MAcDoNALD et al., 1957; KiRA, 1954). This may indicate that the subgroup has the potential to extend up to the northern part of the cool temperate zone. (2) B group (Conifer group without Tertiary type trees) B-1 subgroup: This is characterized by Sciadopitys, Tsuga sieboldii, CryPto- meria, Pseudotsuga and Picea Polita. The northern limit of the distribution of this subgroup lies near the border of cool temperate and subarctic zones. This means that the distribution of this subgroup is slightly warmer than that of B-2 subgroup described below (Fig. 10-b). B-2 subgroup: This is characterized by the presence of Picea maximowiczii, Picea bicolor, Tsuga diverszfolia, Pinus koraiensis and Larix. Their optimum zone is allocated in the areas ranging from the northern part of cool temperate zone to the southern part of the subarctic zone (Fig. 10-b). Such association as that of this subgroup is treated as the indicator of the coldest climate throughout the Osaka group. (3) C group (Broad-leaved group) This is characterized by QLuercus, ,Fagus and Zelkova-Ulmus. The group can be classified into two categories, one with evergreen Quercus and the other without it. When evergreen Quercus is included, the climate corresponding to the vegetation is determined to be of warm temperate. But if evergreen Quercus absent the cli- matic character can not be fixed exactly. It is possible to mention only that the group has its limit around the northern edge of the cool temperate zone (Fig. 1O-b). (4) D group (Warm temperate flora group) Such plants as Podocarpus, Paliurtts and Lagerstroemia which flourish beyond the southern limit of the warm temperate zone are commonly found in this group, Pattern offorest change After the vanishing of typical Tertiary type flora, two forest types, Metaseguoia forest and Fagtts forest appeared. The replacement ofthe forest components seems to have advanced from time to time as follows. (1) Metaseguoia zone a) Metaseguoia A subzone Plants belonging to C group occupy the bulk of this subzone. Besides the C group, such broad leaved trees as Pterocarla, Juglans, Tilia and Celtis appear consistently (TAi, 1970a) and plants of A-1 subgroup still exist in considerable high percentage. This assemblage suggests the climate of the northern part of the warm 156 Akiko TAi temperate zone in which the winter climate is mild and the annual difference of temperature is relatively small. The forest of this subzone may be described as the association ofdeciduous broad leaved forest with evergreen broad leaved trees and the Tertiary type conifer trees, b) Metaseguoia B subzone Components of A-1 subgroup decrease and those of A-2 subgroup increase. Among the C group trees, Zelkova-Ulmus (probably corresponding with Zelkova ungeri) maintains a superior position and Qaercus appears to be wasting away more than in A subzone. Other short trees like Sapium, Ilex, Stptrax, SvmPlocos, Elaeagnus predominate in this subzone(TAi, 1970-b). These facts may indicate that the summer temperature predominate in this subzone. These facts may indicate that the summer temperature is still as warm as that of A subzone. On the other hand, Tertiary type flora such as Keteleeria, GlyPtostrobus and Seguoia which are hardly to stand cold winter climate decline or even vanish in this subzone. This suggests that the winter climate became more severe than in the previous subzone. The climate of this subzone may be interpreted to be similar to the climate along the eastern coast of middle northern Asian continent. In OD-1 core, Picea A and B (probably Picea koribai and Picea maximowiczii) become dominant at the upper part of this subzone. As the present distribution of Picea maximowicaii ranges from the middle to northern part of the cool temperate zone (Fig. 10-b), it can be safely said that the temperature became colder drastically towards the end of this subzone. c) Metaseeuoia C and, D subzones As it has been known paleogeographically that there were repeated invasions of coastal environment during that period, it may be possible to interprete that the results shown in pollen diagram indicating the fluctuation of forest type depend on the degree of the oceanic environmental effects. In the C subzone, Metaseguoia coexists with Fagus and Quercus, and some trees of the A-1 subgroup like Ginkgo still exist. It seems that the winter climate was still mild, although the climate as a whole was similar to that near the northern limit of the warm temperate zone. In the upper part of D subzone (Fr. 2-3), plants of B-1 and B-2 subgroups prevail and broad leaved trees are absent. Picea overwhelms quinquefoliolate Pinus. This is the coldest period throughout the Metaseguoia zone, and corresponds whith the northern margin ofthe cool temperate zone. Mal and Ma2 clay beds, plants of C subgroup have the biggest share. Metasequoia (including Cr"Ptomeria) is usually presnet and Liguidambar is also occasionally found. The climate is supposed to have been similar to that of C subzone. When we observe the general tendency of the fioral change throughout the subzone, it may be recognized, from the spectra obtained from the fresh-water deposits, that B-1 subgroup becomes increasingly dominant in the higher horizons A Study on the Pollen Stratigraphy of the Osaka Group 157 overwhelming the dominant components of A-2 subgroup, such as Picea koribai and Metaseeuoia. The replacement of A-2 subgroup by B-l subgroup seems to have occurred just after the deposition of Ma2 clay. All the trees except for Cryptomeria belonging to the B-1 subgroup, grow along the Pacific coast of the Honshu Island ofJapan (HAyAsHi, 1960) at present, and are considered to be tolerable to cold and dry winter. Thus D subzone is con- sidered to indicate a cooling stage shifting from warm temperate climate to a more arctic one. Several marine clay beds with warm elements in the subzone are interpreted as the product of intermittent warmer epoche in cooling period. (2) Fagtts zone Climatic oscillation and marine invasion: Climatic oscillation which began in the preceding period became distinct in this Fagus zone, and the whole zone can be divided into four subzones, from F to H. Each cycle of strata comprises the following three sections: Section I C group predominating with subordinate B-1 and D group. Section II-a C and B-1 subgroup predominant with subordinate B-2 subgroup. Section II-b B-2 subgroup predominant. The plants of Section I show warmer climatic condition than those of Section II. The plants of Section II-a are inhabitants in the middle to northern part of the margin the cool temperate zone (Fig. 10-b). Thus, it may be true that Section I indicates warm period and Section II indicate cold period respectively. Every fresh-water bed situated between Ma2 and Ma9 yields the pollen as- semblage of Section II, whereas every marine clay yields that of Section I. From this fact, it may be concluded that the invasion of sea water into land corresponds with the time when the climate began to be warm. In E and G subzones, tran- sitions from Section I through II-a to I are seen. The cyclic fluctuation (II-a II-b--sll-a-jLI section) is distinctly recognized in F subzone as well. Forest type of cold period: A coaly clay bed at Manzidani reveals a typical floral change from the II-a type assemblage of the lower horizon to the II-b type of the upper horizon. In the iower horizon the clay yields a little Fagus and Quercus pollen but among them, the former disappear earlier than the latter. In the middle horizon the forest became open mixed forest of Alntts accompanied by Corylzts and Betula. This open mixed forest is situated in the low-lying swampy area surrounded by hilly land with coniferous forest of Pinus koraiensis, Picea bicolor, Picea maximowiczii, Tsuga diversi olia and Larix gmelini (probably associated with such subarctic forest members as Piceaj'ezoensis and Abies veitchii). During the time of the upper horizon, the coniferous forest is supposed to have extended much more extensively than in the time of the previous horizons. Thus, the whole transition seen in this coaly clay bed can be interpreted to be a process of cooling 158 Akiko TAi and drying. Po!len succession at Toyonaka shows the transition from Section I to Section II-a. High percentage of Cryptomeria and Fagus of L-type suggests cool climate having considerable annual precipitation.* This might also held in a cooling period. The floral change from C group to B-1 subgroup seen in the marine clay bed of F subzone may be transitional froin a warm period to a cooler and pluvial. Forest type of warm period: In the D and the E subzone of the marine clay beds, Fagtts and Quercus (including evergreen Querctts) appear almost equally in number, but Fagus becomes more dominant than Quercus towards upper horizons and finally Fagtes becomes dominant in F subzone. The climate of E subzone is postulated to have been that of the northern part of the warm temperate zone judging from the existence of evergreen Quercus. The marine clay bed in G subzone is rich in Crmptomeria and S-type Fagus with occasional appearance of D group elements. Dominant Cr]ptomeria indicates that the rain fall was fairly abundant throughout the period**, and the infrequent ap- pearance of D group elements suggests that the climate was warmer than the present (Fig. 10-b) at least during the limited time when these elements are found. Besides in a limited place like the lower part of the Ma8 at Hirakata Hill, this clay yields abundant evergreen Querctts (PodocarPus is sparsely found as shown in Fig. 2-b). The writer imagines that a secondary forest of evergreen Q;uereus might be present during this period. Similar spectrum is reported from the lowermost part of the Ma6 clay by NAsu (1970). Differentiation of the genus of Fagus: In the lowermost part of the Osaka group, there were four species of Fagus coexisting with each other in the mild cli- matic condition (F.ferruginea, F. ha2atae, F. j'aPonica and F. microcarPa). But in the G and H subzones Fagus varies from S-type to L-type. At least at the time of the G and the H subzones, Fagus might have been differentiated into two types, i.e., warmer temperate type and cooler temperate type. VIII. Pollen stratigraphy and plant remains From paleobotanical studies on the post-Miocene plant remain beds in Kinki district, Japan, MiKi (1948) proposed the following successive fioral beds; Pintts trz:frolia-, Metasegaoia-, Paliurus-, Cr2Ptomeria-, Larix-, SaPium and APhananthe- beds. In connection with this, HuziTA (1954), ITiHARA (1960, 1961), KoKAwA (1961, 1964) and ITiHARA et al. (1965) and many others have made stratigraphical re- * The natural forest of Cr.tptomeria, in the western part of Honshu in Japan is distributed in regions where the annual precipitation is more than 1300 mm, and where the precipitation is less than 1,OOO mrn, even the cultivated Cr]Ptomeria can not stand (SHmEi et al., 1957). This is true in the central part ofJapan as well (TsuKADA, 1967). **It is confirmed (KiRA & YosHiNo, 1967) that at Yakushima Island in southern Kyushu, the natural forest of Cr2Ptomeria extends beyond its warmer limit of threshold temperature in Honshu. A Study on the Pollen Stratigraphy of the Osaka Group 159 examination concermng the deposits from which MrKi had collected samples, and the following successlon has been newly confirmed. Metasequoia bed The Lower formation of the Osaka group. Paliuras bed Lower part of the Upper formation of the Osaka group. Larix gmelini bed Middle part of the Upper formation of the Osaka group. (Fr. 6-7). Syzlgium bed Upper part of the Upper formation of the Osaka group (Ma8). Metaseguoia bed: As for the Metaseguoia bed proposed originally by MiKi (1948, 1955), the date of the bed was considered to be Pliocene in age, but sub- sequently ITIHARA (1960, 1961) divided it into two stages, i.e., that of Metasequoia flora flourishin g age and fMetaseguoiao fiora extinction age. According to ITiHARA, the transition from the former to the latter was attributable to an incursion ofa cold climate, and then,IS. th first cold epoch found in this position was provisionally handled to be 10- the Pl' Pleistocene boundary. Later on, ITiHARA revised somewhat his dea i because ofa new discovery of the evidence ofa cold phase at a still deeper horizon (IBARAGi REsEARcH GRoup, 1966), which is placed between yellow tuff and Shinden Now tuff. it is generally accepted that the boundary between the two Metaseguoia floral stages, in other words, the Plio-Pleistocene boundary is considered theto be interval in between those two volcanic ashes stated above (ITrHARA and 1970). KAMEi, Speaking of stratigraphy, both A and B subzones of the standard pollen suc- cession correspond ghly with rou ITiHARA's Metaseguoia flora fiourishing age. Meta- segaoia flora gflourishin age named by ITiHARA, was otherwise, called the transitional stage from Pinus the trtJlfolia flora to the Metasequoia flora by KoKAwA (1961, 1964). IV2ssa and Car"a are treated as the members ofthis stage by KoKAwA. Regarding the pollen association of Lieuidambar-Nmssa-Car2a, SHiMAKuRA (1957, 1959, 1963, 1964, 1965) deduced the conclusion that the extinction of N7ssa and CarJa has preceded that of Lieuidambar. Concerning the information from pollen spectra, A subzone is characterized by the presence of dominant Lieuidambar, without IV2ssa and Car2a. Consequently, it may be probable that the A subzone of the writer is approximately equivalent to the upper part of KoKAwA's transitional stage or to the upper part ofSHiMAKuRA's Liettidambar-Nyssa-CaTva bed. As for the lower horizon'lying be!ow the A subzone, palynological studies have been made by ONisHi (1968), and ONisHi and NAsu (1968), but more informative data are required in order to discuss it in more detail. In OD-l core, the earliest cold phase is found at the lowest horizon of C sub- zone, i.e., the lower Metaseguoia subzone of TAi (1966). This horizon probably coincides with the bordering part between the B and the C subzones or with the horizon intervening between the yellow tuff and the Senriyama tuff in standard 160 Akiko TAi column. As mentioned before, this horizon is supposed to represent the beginning of the Metasegueia flora extinction age of ITiHARA. The C subzone is dominant in Metaseeuoia pollen (Taxodiaceae I-a type pollen), whereas the D subzone is characterized by decreasing and vanishing of Metaseeuoia pollen and associated pollen of the Tertiary type flora. Taking such features into account, Metasequoia flora extinction age is subdivided into two, a part which bears considerable amount of Metase4uoia pollen and a part with a smal1 amount of Metaseguoia pollen. Paliurus bed: This bed is characterized by many plant remains of the vegatation of warm climate, and also by the predominance of Fagus pollen. Ac- cording to MiKi (1948), it has been occasionally found that the PaliurtLs bed is overlain by thin layer of CrlPtomeria bed. This change from Paliurus bed to Cr]pto- meria bed, in other words, the depositional sequence ofwarm climate to cool climate is consistent with the change of forest shown by the palynological succession from the I-section of Fagus to II¥-section. Miki considered that the Paliuras-Cr7ptomeria transition was occurred only once at one horizon. But it is ascertained that such vegetational change took place not once but several times under the influence of the cyclic climatic fluctuation (Fig. 11). Lan'x gmelini and Slaygium beds: In the Osaka group, the climatic oscil- lation is recognized from the lower part continuously to the upper part. Larix bed may be interpreted to represent the cold climax in a series ofclimatic fiuctuation in F subzone. Slaygium bed which contains indicators of distinct warm climate may have a relation to such spectra which appear occasionally in the G subzone C group B¥1 subgroup Climatic B oscil r. s oscilliation A Cryptomeria ;. ->--¥ bed -- "iiÅ} --- '' T tt . tSN T . N- >- ;.. --' E' G'' l.,illlllllllll " = 1//,,/1111,1//11.1,tll/l/. 'o -- //1.li/y./ g 'tt tN s i $. -Jx.-. g Cryptomeria bed -- . 'II5a;firm O Paliurus bed cold Fig. 11. Interpretation for Paliurtts bed and Ct)f)temert'a bed. " A. After S. MrKi; B, After the present writer, A Study on the Pollen Stratigraphy of the Osaka Group 161 cli:matc Mainmernbersof Zomatienby glgs plantremains Egg¥ Stratigraphicalranges theforest warmperiod Kokawa1961 Age Zone ofprincipalplants 196t coo1-coldperiod Itihara1960 1970 Cryptomeria Fagus-L Sciadopitys HMa9 / Tsuga diveesifolis 1fi11 Cryptomcria Cryptorneria l -- tT7T'-g' Ma8 ./ Fagus-S Tsuga ,i {Evergrecn diversifolia Quercus) GMa7 re 111 e"lgeg' E' 117 BB g& ,1l,ny Pinus Cryptomcria haplexylen Ma6 //1 IN Tsuga FMa5 Tsuga diversifolia 11l1 sicboldii wp.E,m Picea(B) Fagus Larix Ma4 111t1/1 Seiadopitys Cryptemeria EMa3 Fagus Fagus Quercus Tsuga '1 /i / diversifolia l , .// Metasequeia Cryptemeria ¥¥ 1 Liquidambar Picea(A) Ma2 !1'i Evergreen Sciadopitys DMa1 Quercus 11/ Tsuga 1/ 'f Fagus sieboldii gEg,}B Picea(B) MaO EvergrcenQuercus Metasequeia C Fagus l- (DeciduousQuercus sefie 7 -- ?icea(A),B) 1 9.ko gkgg ggg,N Metaseqttoia Picea (A> vg&:¥3'v B Zelkova-Ulmus gg2:.t wt'thmanyotherbroad- leavedtrees. :b¥gElovsug kgBsg ----J- - Trt -t---t Metasequoia,Glyptortrvbes ssx;lI Sequoia(?)Liquidambar, Ketelteria,Ginltgo A Pseudolarix(?) Evergrecn-Deciduous Q!icrcus Fagus-S,Juglance,etc. Fig. 12. Summarized chart of forest change in the Osaka group. "Note" M.-T'. transitional flora: Metaseauoia-Pinus trtfolia transitional flora, after S. KoKAwA (1961). 162 Akiko TAi as the dominance of evergreen Quercus po]len. It must be added that there is another porblem concerning the ecological character of the vegetation of this phase. That is to gay, the dominance of Crypto- meria and the presence of the secondary forest ofevergreen Quercus in the G subzone. It is diMcult but interesting to interpret ecologically such vegetation pattern. The results discussed throughout this chapter is summarized in Fig. 12. Acknowledgement The writer wishes to express her gratitude to Associate Prof. M. ITiHARA of Osaka City University, Prof. K. NAKAzAwA, ProÅí T. KAMEi, ProÅí T. SHiDEi of Kyoto University and Associate Prof. S. IsHiDA of Kyoto University, ProÅí M. SHiMAKuRA of Nara University of Education and ProÅí J. UENo of Shizuoka Uni- versity for their generous direction and encouragement. Thanks are also due to the members of the Osaka Group Research Group for their continuing interest and encouragement in the field and laboratory. This work was made possible by a helpfu1 assistance from the Department of Geology and Mineralogy, Kyoto University, for which she expresses her appreciation. References FAEGRi, K. and J. IvERsEN <1964): Textbook of pollen analysis 2nd,, Blackwell Scientific Publica- tions, Oxford. 237 p. FuKAKusA REsEAcH GRoup (1962): Plio-Pleistocene deposits at Fukakusa, southeast Kyoto.-The research ofYounger Cenozoic strata in Kinki District 1. "Chiklu Kagaku" (Earth Science), No. 63, pp. 1-7. (inJapanese with English abstract) HARATA, T., S. IsHiDA, I. ONisHr and T. ToKuoKA (1963) : Plio-pleistocene deposiLs in Izumi region, South of Osaka.-The research of Younger Cenozoic strata in Kinki Province III.-ibid., No. 66, 6, pp. 1-8. (in Japanese with English abstract) HAyAsm, Y. (1960): Classification and distribution of the natural forestof coniferous trees, indigenous toJapan. Norin-Shuppan, Tokyo. (inJapanese) HuziTA, K. (1954) : Stratigraphical significance of the p!ant remains in the late Cenozoic formation in Central Kinki. Jour. Jnst. Pogvtechn., Osaka City Univ., G. 2, 2, pp. 174.-316. IBARAcTi REsEAcH GRoup (1966): The Osaka group of Fukui area, north of Ibaragi, Osaka Pre- fecture, and Occurrence of ElePhas sigensis. Prof. Matsushita Memor. Vol., Kyoto, pp. 117-130. IKvsE, M. (1956): Pollen ofJapan. Hirokawa-Shoten, Tokyo, 237 p. (inJapanese) IsHmA, S., K. MAENAKA and T. YoKoyAMA (1969): Paleomagnetic Chronology of Volcanic Ash of the Plio-Pleistocene Series in Kinki District, Japan.-The reseach of Younger Cenozoic strata in Kinki District, 12-Jour. Geol. Soc. JaPan. 75, 4, pp. 183-197. IvHARA, M. (1960) : Some Problems of the Quaternary sedimentaries in the Osaka and Akashi area. "ChikJu Kagaku" (Earth Science) No. 49, pp. 15-25. (in Japanese with English abstract) -. (1961): Sorne Problems of the QLuaternary sedimentaries in the Osaka and Akashi area. Jour. Inst. PolLJ,techn., Osaka City Univ., Ser. G, 5, pp. 13-30. .(1970): Some Problems of the Osaka Plain. "Dai7onki", No. 15, Special number of Coastal Plain, pp. 17-19. (in Japanese) ., K. HuziyA, A. MoRisHiTA and K. NAKAsEKo (1955): Stratigraphy of the Osaka group in the Senriyama Hillg. Jour. Ceol. Soc. JaPan, 61, pp. 433-441. (inJapanese with English A Study on the Pollen Stratigraphy of the Osaka Group 163 abstract) . and T. KAMEi (1970) : The Osaka GroupeThe Geology of Plain and Hilly regions, "Kagaku", 40, 6, pp. 282-291. (inJapanese) ., T. YoKoyAMA and S. IsHmA (1965): On the Manchidani forrnation. JaPtm. Quat. Res., 5, 2, pp. 65-72. (in Japanese with English abstract) KAMEi, T. (1969): Invertebrate fossis from the Osaka group and its equivalents. Res. commttntc. Osaka GrouP, No. 4, p. 15-l7. (in .Iapanese) .and T. SEvoGucHi (1970): Some remarks on Mamrnalian Faunas in the Early Pleistocene. JaPan. Quat. Res., 9, 3-4, pp, 158-163. (inJapanese with English abstract) KANEHrRA, R. (1936) : Formosan Trees, indigenous to the Island. 2nd., Repert from Department of Forestry Geryernment Research Institutes, Formosa. (in Japanese) KiNKi GRoup (1969): Q;uaternary systcm ofKinlti District,Japan. "Chidunken-Se,ipo", No. 15, pp. 331-354. (in Japanese with English abstract) KiRA, T. (1945 a): Thenewly revised climatic division of the Far East as a foundation of the agricultural geography. MimeograPh. DePart. Horrkulture, K2oto Univ. (inJapanese) . (1945 b) : The new climatic division of the soutern region of the far East. ibid. (in Japanese) . (1948) : On the altitudinal arrangement of climatic zones inJapan. A contribution to the rational !and utilization in cool highland. "Kanchi Nogaku", No. 2, pp. 143-173. (in Japanese) .(1949): Japanese Forest Zonesi Explanatory Series ofForest(v, 17. (inJapanese) . (1954) : Some problerns on the presumption on the climatic history by means of the plant remains. JaPan. Jour. Ecol., 4, 1, pp. 1-6. (inJapanese) . (1958): The natural construction of ecological system in high land. Seibutsu to Kankyo (The¥life and Environment) pp. 231-269. Kyoritsu-Shuppan, Tokyo. (inJapanese) . and M¥ YosmNo (1967): The temperature distribution of the Japanese coniferous trees. "Shizen"-Ecological study-1, pp. 133-162. Chuokoronshia, Tokyo. (n Japanese) Koi[AwA, S. (1959) : On the plant remains and its floral change, found in the vicinity ofNishinomiya City. History of IVishinomi a City, pp. 265-285. Nishinomiya, (in Japanese) . (1961): Distribution and Phytostratigraphy of Menlanthes remains inJaPan. Jour. Bot., Osaka City Univ., 12, pp. 123-151. . (1964): Plant remains found in the vicinity of Hamamatsu. Btdt. Geol. Surv., pp. 203-235. Hamamatsu City. (inJapanese) Lr, Hur-LiN (1963): Vi'oody flora of Taiwan. The Morris Arboretum and Divisien qf BiologJ, Univ. Pensylvania. MAcDoNALD, J., R. F. WooD, M. V. EDwARDs and J. R. ALDHovs (1957): Exotic Forest trees in Great Britain. Forestry. Commtsson Bulletin No. 30, Bn'tish Cbmmontvealth Forest Conference Australia and IVew Zealand. MiKi, S. (1941): Floral remains of Conifer Age at Manchidani near Nishinomiya, Japan. JaP. Jour. Bet., 11, pp. 377-383. . (1948): Floral rcmains in Kinki and adjacent district since the Pliocene, with de- scription of 8 new specSes. Min. ec GcaL, 2, pp. 105-144. (inJapanese with English abstract) . (1950): Taxodiaceae ofJapan, with special reference to its remains. Jour. Inst. Po4vtechn. Osaka City Univ., 1, Ser. D, pp. 63-77. . (1955): On Metaseguaia, Forsil and Living. IViPtPon Kebutsu Shumi-ne-kai, 141 p., Kyoto. (in Japanese) . (1956): Remains of Pinus koraiensi's S. et Z. and associated Remains in Japan. Bot. Mag., 69, pp. iM9-454. ., K. HuzrrA and S. KoKAwA (1957): On the occurrence of many broad leafed ever- green tree remains in Pleistocene bed of Uegahara, Nishinomiya City, Japan. Proc. JaPan Acad., 164 Akiko TAi 33, 1, pp. 4146. ., S. HiKrrA and S. KoKAwA (1962): Floral change of the Plio-Pleistocene. Fossil of Osaka. (Meeting for Osaka Science Study) pp. 16-18. (inJapanese) NAKAMuRA,J. (1956): The size frequency of Querczts pollen. Sci. RePt. Kochi Univ., 5, 21, pp. 1-5. . (1957): A pollenanalytical study of the Yawata Swamp, Hiroshima Prefecture. Bull. comPresh. stted. nat, sm'. Sandarkyo Gorge and Yawata Highland Hiroshima, JaPan. pp. 153-160. (in Japanese with English abstract) . (1968) : Palynological Aspects of Quaternary in Hoklcaido. V, Pollen succession and climatic change since the upper Pleistocene, Res. RePt. Kochi Univ., 17, Natural Sci., No. 3, pp. 40-51. (in Japanese with English abstract) NAsu, T. (1970): Palynological study on upper Osaka group in Kinki District, Japan. "Chiklu Kagaku" (Earth Scimce), 24, 1, pp. 25-34. (inJapanese with English abstract) NisHrMuRA, S. (1969): Age determination of the tuff layers of the Osaka group by means of the fisson track method. Res. Commttnab. Osaka group, No. 4, pp. 22-26. (inJapanese) .and S. SAsAziMA (1970): Fission track Age of Volcanic Ash-layers of the Plio- Pleistocene series in Kinki District, Japan. "ChikJu Kagaku" (Earth Science), 24, 6, pp. 222-224. (in Japanese with English abstract) NiREi, H. (1968): Plio-Pleistocene florae of Takatsuki Region, Osaka Prefecture, (]entralJapan. Jour. Geol., Osaka City Univ., 11, Art. 3, pp. 53-78. . (1969): Early Pleistocene florae of Kanazawa Region, CentralJapan, with special reference to the evolution of Juglans. ibid., 12, pp. 7-24. ONisHi, I. (1968) : Pollen flora of the Kazusa group in the Boso peninsula, Japan. "Chik.vu Kagaku" (Earth Science), 23, 6, pp. 236-242. (inJapanese with English abstract) .and Y. NAsu (1968): Some problems on the Plio-Peistocene boundary in the view peint offossil pollen. Daiponki Kenk7a Renraku-shi, No. 12, pp. 29-32. (inJapanese) OsAKA Czry (1964): Report on the fundamental survey of land subsidense in Osaka. Report qf OD-1 drilling bore hole, 213 p. (inJapanese) OsAKA. GRoup REsEAcH GRoup (1951): The O$aka Group and the related Cenozoic Formations. "Ch*7tt Kagaku" (Earth Scdence), 6, pp. 49-60. (in Japanese) SATo, S. (1965) : On the size ofFossil pollen grain. ¥IaPan. Qttat. Res., 4, 3-4, pp. 132-143. (inJapanese with English abstract) .(1967): Some problems on the palynological study in Japan. Prof. Sassa Memer. Vot., Sapporo, pp. 135-143. (in ,Japanese) SHll)Ei, T. et al. (1957) : Investigation on the natural distribution ofSugi (CTJtPtomeriaJ'aPonica) and the selection of its natural elite race in the western part ofJapan. Osaka nationalforest Bureau, Osaka. (in Japanese) SmMAKuRA, M. (1956): Pollen stratigraphical studies of the Japanese Cenozoic formation I.- Method and general problem. RePt. DePt. Eartk Sci. Nara Educ. U'niv., 6, II, pp. 57-64. (in Japanese with English abstract) . (1957): Pol]en stratigraphical studics of theJapanese CenQzoic formation II.-The Harakawa formation of the Nijo group. ibid., 7, 2, pp. 35-42. (inJapanese with English abstract) . (1959): Pollen stratigraphical studies of the Japanese Cenozoic formation III.- The Kobe group and Akashi group.-ibid,, 8, 2, pp. 65-75. (in Japanese w!'th English abstract) . (196S) : Pollen stratigraphical studies of theJapanese Cenozoic formation VII.-The Jigoku-dani formation.-ibid., 11, pp. 13-24. (in Japanese with English abstract) -+ . (1964): Pollen stratigraphical studies ofJapanese Cenozoic formation VIII.-The Suge, Soni and Tsugeno groups.-ibid., 12, pp. 37-50. (inJapanese with English abstract) . (1965) : Pollen stratigraphical studies of theJapanese CenozQic formation XI.-The Paleo-Biwa group.-ibid,, 14, pp, 25-39. (in Japanese with English abstract) SuzuKi, K. and KAMET, T. (1969): The change of the forest and Traveling life. "Kagaku", 39, 1, A Study on the Pollen Stratigraphy of the Osaka Group l65 pp. 19-27. (in Japanese) TAi, A. (1963) : Pollen analyses ofthe Quaternarydeposits in the FukakuLga and Hirakata Districts.- The research of Younger Cenozoic strata in Kinki Area 1.-"Chik)u Kagaku" (Earth Sbience), No. 64, pp. 8-17. (inJapanese with English abstract) . (1964) : Pollen analisis ofthe Osaka group in the Hirakata HM, with special reference to the relation between Climatic change and Marine and Terrestrial deposits.-The research of Younger Cenozoic strata in Kinki Province IV.-ibid., No. 74, pp. 22-32. (in Japanese with English abstract) . (1966): Pollen analysi.g ofthe Core (OD-1) in Osaka City.-The research ofYounger Cenozoic strata in Kinki Province, V.-ibid., No. 84, pp. 25-33, pp. 31-38. (in Japanese with English abstract) . (1969): Pollen analysis of the Early Pleistocene sediments of the Osaka group at Machikaneyama, Osaka, Japan.-The research of Younger Cenozoic strata in Kinki District, 14.-ibid., 23, 4, pp. 142-148, No. 5, pp. 199-206. (inJapanese with English abstract) . (1970 a): Pollen analisis of the Upper Pliocene sediments of the Osaka group at Tsuchimaru-Oike, Osaka, Japan.-The research of Younger Cenozoic strata in Kinki District, 15.-ibid. 24, 2, pp. 43-¥48. (inJapanese with English abstract) . (1970 b) : Pollen analysis of tlie Lower part of the Osaka group at Senriyama, Osaka. -The research of Younger Cenozoic strata in Kinki District, 16.-ibid., 24, 5, pp. 171-181. (in Japanese with English abstract) . and J. UENo (1965) : On the fossil pollen grains of Psetedolarix type (some Pliocene palynological notice ofTannowa, Osaka Prefecture). Acta. Ph7totex. Geobot.,21, 5-6, pp. 141-146. (in Japanese with English abstract) TAKAyA, Y. and M. IiiHARA (1961): The Quaternary deposits of Hirakata Hil1, with special re- ference to climatic changes recognized in Sinkori and Hirakata members. Jour. Geol., 67, pp. 584-592. (in Japanese with English abstract) . (1963) : Stratigraphy of the Paleo-Biwa group and the Paleogeography of Lake Biwa with special roference to the origin of the endemic species in I,ake Biwa. Mem. Coll. Sci. Kpato Univ., Ser. B, 30, 2, pp. 81-119. TAKETsuzi, T. and M. ITiHARA (1967) : The Osaka group in the Central part of Senriya:na Hills. Reg. Commtotab. Osaka grouP, 1, pp. 6-11. (inJapanese) TAKEoKA, M. (1959): Consideration on the size frequency curve in the main forest trees. (1)- Especially on the po11en of genus Pinas and QuepTcus.-RePt. Salvo Univ., jForest., 3, pp. 21-27. (in Japanese with English abstract) TsuKADA, M. (1966): The history of Laguna de petexil. Mem. Cemm. Acad. Arts. Sci., pp. 17-65. . (1967): The last 12,OOO years: A vegetation History ofJapan I. Bot. Mag. Tok]o., 80. pp. 323-336. (in Japanese with English abstract) UENo,.J. (1951): MorphologyofPollen ofMetasequaia, SbiadoPitysand Taiwania. Jour. Inst. Po!vtechn. Osaka City Univ., Ser. D, 12, pp. 22-26. . (1957): Relationships ofgenus Tsnga from po11en morphology. ibid. 8, pp. 191-196. .(1958): Some palynological observation ofPinaceae. ibld. 9, pp. 163-178. VAN CAMpo-I]it;pLAN, M. (1950) : Recherches sur la phylog6nie des Abi6tin6es d'apres leurs grains de pollen. Trav. du Lab.forest de Toulozase., 2, 4, art. I., pp. 9-182. WANa, CHi-Wu (1961): The forest of China, with a survey ofGrassland andDesertvegitation. Maria moor Cabot. Found. Publ., 5, Harvard Univ., Cambridge YAMAzAKi, T. and S. TAKEoKA (1956) : On the identification of the pollen of Taxodiaceae. Rept. Saik2o Unit'., Forest., 8, pp. 10-16. (inJapanese with English abstract) Appendix-Figure ' ' DISTRIBUTION OF TERRACES IN THEINA VALLEY,CENTRAL JAPAN (SHIMIZU, H.) : sas g¥e qdD .sty 9 PMMMIMIIII INA suRFAcE {IE ) dt[trp l " i: s ua TAKAO TERRACE-1 ( TK¥1 ) 0 -,,1 Åé &N .. , "i : E ww TAKAO TERRACE-2(TK-2 } ba ll 1 -t ctsllllii M[Uiptt, :'e llilillili:ii olzuMI TERRAcE( oz ) 1 ¥39 , ¥:':' j i19J¥ , --1j/ '111 t' i'sr."ii;f'::'i;'i:¥ YOKOMAYA TERRACE ( YK > sty t 7. .1 . IE.I'.t` ¥ Il tl gty ;1 T ii', '. - MIKOSHIBA TERRACE-l ( MK-1 ) si` -i ste aul IEi2il N" Il iE " --t -i-l -:: N" "MD¥ 11A o [III[IIIIIIIIIIIII MiKosHiBA TERRAcE-2 c MK¥2 ) i keW " :-:(+ y . tl7741 ,, g "" sr l ii i¥'th'i'i-' '' ':' -ltt 11 :i::'::,:.::i:Iii MINAMIDONO TERRACE{MD) : i i f' -l-;-l-I-l-i- KINOSHITA ;I'ERRACE-1CKS¥i} .M,P '"-t t l : ' t' ILill:iI1:il KINOSHITA TERRACE¥2(KS-2) 2 , 2b.2: 1 il s 2, ots .ZZt.(z'2' KINOSHITA TERRACE-3CKS¥3) '-' ¥:MP¥ ty ?1 ,l schinos"pt , Obinasthi. ¥:M,' lo:¥' '' X LOCALITY @CITY HALL eetoa K¥2 MK-1 .e;XN-136 '' ¥' ¥:::¥:::::::1,opp:::::¥.¥. eZ' o TOWN OFFICE e VILLAGE OFFICE Oie i SIii, etel¥ : ¥,i¥,Igi?,, 3'¥: ;. I: ,S; B -t--t- ",: e ¥1 ¥ii¥i ii) --tt -t !l:il::i ------d t +-t.-t ti¥ -t--- --+ .:.,!.:D.i::::.:::.:.. Z... - ' A t¥;¥:¥::::::i::'::,.xz?, :. '"' vl s" Åí -,l tl M ¥2 ' """" ,I-. 1i1ti sX¥ s-E . :.2ÅÄ1,,1,: ; 2 "Z .'t:::.: fa" 9 t.2,.-:1:IM,.PI:.:::::, :N:la'3Q oeeso.olkn "¥+ -s ,i "ty ¥ tt- '-' rX stv 2 !N9IW,A id1l- 't' 1 1- i ":H .:-,", e 1, ' as I l. :¥tT¥i':r' t i" " M ¥2 11,:/1: o to ' ti' :,MPI¥ -E ' N¥2 a stw .'.'¥i,,v..,S-1 x MK¥1 't r ¥1 :t:.: " ¥l' ¥t:.,. -- a2 ,ety aiiiimiiiiiiiiiiii t?:':"s't t 4ttt-tt"t' :tt--,:- :::t 1;'-4. '!; YKI;{i z",';':t, ?l MD' t.s::i ,' oo ::::rk :iT' '- 11 'NS L, ¥¥ is,, , V'1:'I::' 3t ¥32 ,,y¥g," -:.-: t-tttt 2nyN 'S:1 tlt tt: ./2" '"¥;-.. a N l' 11,:,s ,,, :,:,::¥NP,:,:']I]:,:,1.:::,, - -' d (l?st 1,11::1::11:::1::1:::i'D":: :1:::::::1':':N' '¥:¥a . 'i'ww ,¥ .¥,,, lgeiggif' .Gawa Gawa KS.1.i Ne b" aRfiiEZta MK¥ Mi giiilii ' o" ,1ilil ,-::'wh61:1: , l:: ¥2.2't '' I:.:, ., :Me:/i:¥ K¥ iiil) :¥M,D,1,¥ ¥¥ f l ¥' ¥' ¥L¥¥¥ MK-1 l- I' i: 1 K¥ I+¥,ft-2:: ll/ : ""' : S tt,.. MK- e m': i¥ d .2 kg,' "{ i +-p g K-2 ' tl l 9 ' ASE e (i[fiiii!iiii -l Åë ,I v palf g N :pa- i--- -t-- i e ''- s iiiifl !iiilllllii? - --th- 1 D Kvro- Kawa .ll[6 eg ' ? tt rtt t/ t tlttl rt ttt t/ ,"" t ' K¥2 x' i r::1-] IYt t xx¥ ;2.. ,2¥' 2' 2'¥Z¥"{ i"" M-194 ' .¥.¥,¥g¥f li s-- ltl vl g-crs O t aet' tiivl- t't scbZ e.., -¥ MtC¥1 i-Caw 9 1 wR. MK¥2 , s K¥1 lilMl nv dfand)) o G le i ll ¥7 Ksl ff ewgeb MK¥2 ge as op , + ffiJ, va "a" eieeiri.c M ii 11Lll: 1 ' eqee l gzziiiiii i',i,1l xM¥12 th ¥ - ll ld , c t' ',E' ¥ "" i"s..'. lr '. .".'' s ge pt ¥ iy -i --\rp - r es :ldl + ,]:S:¥:¥l,i ''i ¥"s :: :+1 KS¥21 11 1 1 IMA g 11bbl : --- :¥l¥ il)1 h:,:,¥.:}:.¥k,.:t: , - :tttJ tt p 1tJ 1 Yotagiri-Cawe b ))l:p M -2 x, 'i sclrtkES5 A g S onu"n'-Gawa Tenryu-(]awa :¥:¥MD¥i¥ii:1 liii) B A MK¥1 byee #¥¥ loooM MK¥2 MD MK¥2 OZ MK¥2 KS¥1 MK.2 1 eeupe li MD KS¥2 'cawb l3 -t -:t:"-t , imin/fm::':i':¥i'iiiili':¥;'{:'::¥/r¥'tt¥¥/T/:lt:,[l¥:.:¥il.¥:',ii¥jI'j`,;:,`¥::.,{'i.¥t,¥{¥;¥;¥tii:¥:¥i.:.:¥.:¥.:,¥t.¥`.:i,¥i¥,¥E¥,,¥,,,...,.., l K VKi:¥, 1 iaR" 1'}'t:tY¥ l'¥:s¥ggi.fe¥: :¥ :¥:¥:-:,-¥:::¥:¥; ;i:-:¥iii;:ii¥¥fimM :ere ' ' !e" aO Basement ¥::;i.:,.,¥di¥rtm 'r;". o eth t9 e l ;gliliigee edi Kect h i b u - awa E TK¥ ¥-:¥:¥MD:1¥:¥:,¥ .KS¥1'. - MK¥ ld ,i:¥111:lilllS:1: ,I,i,5;R i 11 .MATSUA .,, .i ,. L.,u:,S , :b A to ggiii! ' -t-+----b -l-t-s--- ) -- ttt"-t- -. -+ l.-ft)-- t b : ' :t '',,=/ 1d : F::.inbJ;,, t:-: - i : l Nakatagiri-(]awa o. ¥t2.,. MK'', ,tiklt,ii,i¥i,¥,l, ' IH-i IE Tenryza-Gawa :l I t ' ' 2 6. li lt/ .' 3e .¥ i..¥z , oo MK¥2 TK¥1 MK¥2 ¥2 ¥2 MK¥2 M MK¥2 MK-2 OZ oz ee li d '- -'" MD 1 IE 1ooOmC MK-2 D Åë ,at[ll:-'MK¥i1' F om os )XS-2oo i-:-:-i:-:t-:-:i::-:-:-:-:-:-:-:--:----:-::--t:-:::-::--:e:--:------ty L Nin-:i------t-- ' e. fo 1/ 1 -P9 O. : rrli'rf'iii";'::: :': ': ':i:' 1' :' I:":": :' :. 'i: i .: :' :'", :i;I: :':.:.: :.: :,:: :::: e.:.: .: :. :.: .. ., l .d t. .1 ;'-,KS ) o ansg!mmD 'ts., qqopb ta e/su+ t '"... S-l TK. g,tw ,ill Tenpat¥(laua -L' -iKs:1 -.- . -@ KANAE l Osawa-(]aua Ina Surface •,L,•,•,MD:ÅÄ•':: KI TK¥1 TK¥2 MK¥1 M"- z S¥2, OZ MD MDKS¥3 ¥1 10co s: :' t mE f i KS¥3 Ks-3 oz i , t KS¥2 ,li.tlk:li,:,, Cawa , mummmfi F xs- "titP'.- ,. .qb fll:li':':'i'::':':"':' l ¥,,,. ': #'`':" ma ../Iiii'I'lsl-l,/f-;- i':'!ii." .dd d wn ' t ' KS¥2 o z ''i::", ' t/ 1 llMfi"ti""":':';':::¥:¥:::':::¥¥ ,,l yx1.. s¥1' 1 ¥:;":'i' /i'm"m'm ' mma¥¥¥¥¥¥¥¥¥¥-:::::"¥¥¥¥¥¥¥:¥¥ ¥:' , ,,, ;Ii¥I¥ ¥ ,i,¥1'ilI¥i¥i:]:¥1¥1l,;.l;i¥11¥:¥:¥IX:ii':i:nt"'in'fi' i l/ 1.b mwh;¥:¥::¥:¥:¥:¥::":::¥¥:.::':¥:¥::':::' ':':e,':"'/';i':::'-,,t,;.: tsopan- -- -t-t-te -t-i .-ll-1{iils i¥¥-¥gl¥'.it/i i,'I¥ "r. r¥ .ed 'tt 1- iE itk- -L." "¥ae - i, KSZ'eult e" KAWAZ''i te /"b bl ;'¥,i' e, ¥ il lt ' TA TSUE e,, ¥l--i ?.,:::¥"" x XllEb 'I:I'¥:-, tddt '¥Ks¥v x ,,,i,M,,Qss'¥ --- td/ ,¥i';---¥ll[,, --- o 1 2 3, 4 5 10km --- 1 gtait(nil . pax E