The Journal of the Geological Society of Japan
Online ISSN : 1349-9963
Print ISSN : 0016-7630
ISSN-L : 0016-7630
Volume 47, Issue 563
Displaying 1-6 of 6 articles from this issue
  • Toyofumi YOSHIMURA
    1940 Volume 47 Issue 563 Pages 297-305
    Published: August 20, 1940
    Released on J-STAGE: April 11, 2008
    JOURNAL FREE ACCESS
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  • Hideo INUZUKA
    1940 Volume 47 Issue 563 Pages 306-309
    Published: August 20, 1940
    Released on J-STAGE: April 11, 2008
    JOURNAL FREE ACCESS
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  • Hiromu ONISI
    1940 Volume 47 Issue 563 Pages 310-317
    Published: August 20, 1940
    Released on J-STAGE: April 11, 2008
    JOURNAL FREE ACCESS
    In the present article is abridged the writer's observation on the Neogene geology of the environs of Kozai-mura, northwestern slope of the Abukuma mountain range ; with particular reference to the stratigraphical position and faunal content of the shell-beds., The order of succession of the different rocks, as observed by the writer, is as follows, in descending order., Yosigazawa shell-bed {Sandstone with fossil molluscs Conglomerate ···unconformity···Kozai shell-bed···Alternation oftuffaceous sandstone and tuffaceous shale with fossil molluscs···slight unconformity···Kanayama bed ···Shale Alternation of sandstone, shale and tuff with lignite seams and plant fossils It is now recognized that, following the deposition of the Kozai shell-bed in the shallow syncline of the Kanayama bed, the younger Yosigazawa shell-bed then was deposited over the eroded surface of the first mentioned two beds., From the molluscan assemblanges of the Kozai shell-bed and the Yosigazawa shell-bed, it appears that the former can be correlated with the Lower Sawoyama series (Moniwa beds) and the latter with the Upper Sawoyama series, in the environs of Sendai., In the northern part of Sendai, the Kozai shell-bed is probably equivalent to the Otutumi beds and the Yosigazawa shell-bed corresponds to the Aoso beds., The geological age of the Kozai and the Yosigazawa shell-bed may be Lower Miocene, in a two-fold division of the Miocene, or Lower and Middle Miocene respectively, in a three-fold division., Further the writer intends to undertaken mor advanced studies, to make clear the relationships of the different beds mentioned in this article.,
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  • Shoji IJIRI
    1940 Volume 47 Issue 563 Pages 318-327
    Published: August 20, 1940
    Released on J-STAGE: April 11, 2008
    JOURNAL FREE ACCESS
    Fro his sfudy on the variation in the teeth of Desmostylus, comparing them with that of the human teeth, the author finds that they show a tendency of degeneration, and concludes., That Desmostylus is a degenerate mammal., It is therefore inferred that the geological distribution of Desmostylus is limited to a narrow range of time (Middle Miocene)., This inference has been confirmed by stratigraphic studies.,
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  • Tuneteru OINOMIKADO
    1940 Volume 47 Issue 563 Pages 331-338
    Published: August 20, 1940
    Released on J-STAGE: April 11, 2008
    JOURNAL FREE ACCESS
    The Amaze Oil Field is situated in Izumozaki-mati, Niigata-ken and eight samples collected therefrom constitute the material of this research., More precisely, three of them were collected from the Haizume-Formation, one from the Nisiyama Formation, three from the Siiya Formation, and one from the Teradomari Formation., Fig., 1 shows these fossil localities., The significant Foraminiferas of the faunas contained are listed in Table 2., Haizume Formation: Loc., 55 and Loc., 57 are situated nearly in the same horizon., Loc., 58 is somewhat upper in horizon than the former two localities., The leading members of the Foraminiferan fauna from Loc., 55 and Loc., 57 are Textularia sagittula, Quinqueloculina vulglaris, Cassidulina japonica, Globigerina bulloides and Cibicides lobatulus, Cibicides refulgens is predominant in Loc., 58, but Cassidulina japonica is not found in it., The Foraminiferan fauna from Loc., 55 and, Loc., 57 reveals a close affinity with that of Kutta which YABE and HANZAWA reported in 1923., Here I suggest the Kutta assemblage to designate this fauna in the Amaze and the Nisiyama Oil Fields., Nisiyama Formation: Only one sample was collected, and the Foraminiferan fauna is very small in the number of species and individuals., Siiya Formation : Three samples were at hand., Haplophragmoides subgrobosum and Goesella sp., 1 are dominant in the one from Loc., 66 and a few species of Nonionides, Buliminidae and Rotaliidae are contained in the two others, but the predominant species in the Haizume Formation can not be found in this., Teradomari Formation : Cyclamina pauciloculata is common., In order to show the relative abundance of different families in the three localities, Loc., 58, Loc., 55 and Loc., 57, in the Haizume Formation, a value is arbitrarily assigned to each letter in the cheek list : R=1, C=10, A=20., Table 3 shows the number of abundance for each family based on these approximate figures and the percentage of abundance for each family in the three localities when the total number of abundance in Loc., 57 was taken as 100., Fig., 2A is a graphic interpretation of this table., Fig., 2B shows the relationship of the families in twelve localities in the Higasiyama and Araya Formations of the Higasiyama Oil Field.,
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  • Fuyuji TAKAI
    1940 Volume 47 Issue 563 Pages 339-342
    Published: August 20, 1940
    Released on J-STAGE: April 11, 2008
    JOURNAL FREE ACCESS
    As fossil elephants have not been known from the prefecture except Stegodon orientalis shodoensis described by H., MATSUMOTO, the present occurrences are of special interest., The one discovered in the Wanazu sandstone formation at Okada, Takayanagi-mura, Kariha-gun is Parastegodon cf., akasiensis and the other found in the Oguni brown coal bearing formation at Sizyuppo, Tatibana-mura, Naka-Uonuma-gun, is Palaeoloxodon namadicus naumanni., In regard to the horizons which yielded the fossils, the former is indicative of the early Pleistocene age and the latter of the late Pleistocene., Since Pleistocene deposits are not very well represented in the region and opinion has generally been that the Wanazu sandstone formation is late Pliocene, the find of Pleistocene mammalian remains provides important keys for future research., Finally it may be noted that MATSUMOTO's specimen may possibly be misidentified for it appears to me to be identical with Parastegodon cf., akashiensis.,
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