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Volume 64 (2010)
- Issue 6 Pages 209-
- Issue 5 Pages 179-
- Issue 4 Pages 147-
- Issue 3 Pages 93-
- Issue 2 Pages 53-
- Issue 1 Pages 1-
Volume 64, Issue 3
Displaying 1-6 of 6 articles from this issue
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Atsuo KOTAKI, Kyoto Research Group of Earth Science EducationArticle type: Article
2010 Volume 64 Issue 3 Pages 93-94
Published: May 25, 2010
Released on J-STAGE: May 16, 2017
JOURNAL OPEN ACCESSDownload PDF (1325K) -
The basaltic dikes in the new outcrops which appeared in Kawamata-machi, Fukushima Prefecture(Photo)Shigeki CHIBAArticle type: Article
2010 Volume 64 Issue 3 Pages 95-98
Published: May 25, 2010
Released on J-STAGE: May 16, 2017
JOURNAL OPEN ACCESSDownload PDF (2396K) -
Kanichi KITANI, Yusuke KAMOArticle type: Article
2010 Volume 64 Issue 3 Pages 99-109
Published: May 25, 2010
Released on J-STAGE: May 16, 2017
JOURNAL OPEN ACCESSThe stratigraphy of the Quaternary sediments around the Kyoto Basin was made by correlations of the marine clay marker bed and the characteristic volcanic ash layer. Pleistocene sediments in the southern part of the Kyoto Basin are mainly consisted the Osaka Group and Pleistocene terrace deposits. The marine clay marker beds of the Osaka Group in this area are already founded twelve marine clay marker beds (Ma0, Ma1, Ma2, Ma3, Ma4, Ma5, Ma6, Ma7, Ma8, Ma9 and Ma10 beds). However the marine clay maker beds of the KD-0 deep drilling are only founded three marine clay marker beds (Ma3, Ma5 and Ma6 beds) of the Osaka Group. This paper represents the stratigraphy of KD-0 deep drilling is summarized as follows. The marine clay maker beds of the KD-0 deep drilling are newly founded eleven beds (Ma0, Ma0.5, Ma1, Ma1.3, Ma2, Ma4, Ma7, Ma8, Ma9, Ma10 and Ma12 beds). The discovery of Ma10 and Ma12 bed in the southern part of the Kyoto Basin is important on considering of Pleistocene terrace deposits sequence in the Kyoto basin and the northeastern part of the Osaka plain.View full abstractDownload PDF (1842K) -
Masatoshi GOTO, Takeshi TANAKA, Satoshi UTSUNOMIYAArticle type: Article
2010 Volume 64 Issue 3 Pages 111-116
Published: May 25, 2010
Released on J-STAGE: May 16, 2017
JOURNAL OPEN ACCESSA tooth of hybodont shark, Lissodus sp. (Hybodontoidea; Elasmobranchii) from the limestone of Taho Formation (Spathian, Lower Triassic) of Kamigumi, Taho, Uonashi, Seiyo City, Ehime Prefecture, Southwest Japan was described. The crown of the tooth has an elongated rhomboid occulusal surface. The occulusal surface has a low main cusp and there is a transverse crest from which many striae diverge towards the labial and lingual margins of the crown. This is the first report on Lissodus from the Lower Triassic marine deposit of Japan. This report will be significant to consider the transition of distribution and habitat of Lissodus in Early to Middle Triassic age.View full abstractDownload PDF (1080K) -
Rustam OROZBAEV T., Apas BAKIROV B., Akira TAKASU, Michio TAGIRI, Kady ...Article type: Article
2010 Volume 64 Issue 3 Pages 117-126
Published: May 25, 2010
Released on J-STAGE: May 16, 2017
JOURNAL OPEN ACCESSEclogite blocks occur within a serpentinite body in the Orobashy area in the Kyrgyz Tien-Shan. A serpentinite body 300m×1,800m in dimension contains blocks of eclogites, garnetitites, garnet amphibolites and gneisses. The eclogites are composed mainly of garnet, clinopyroxene (sodic-augite), amphibole (magnesio-hornblende, tschermakite, pargasite and actinolite) and rutile with minor amounts of quartz, epidote, plagioclase, K-feldspar, biotite, paragonite, phengite and chlorite. The minerals included in the garnets of the eclogites such as epidote, amphibole (tschermakite, pargasite and magnesio-hornblende), biotite, paragonite, phengite, K-feldspar, plagioclase, clinopyroxene, rutile, and quartz are suggested as the minerals crystallized before the peak metamorphic stage. These minerals are probably divided into two groups; minerals of the precursor metamorphic event before the high-pressure type eclogitic metamorphism and those of the prograde metamorphic stage just before the eclogitic peak metamorphic stage. Coexistence of garnet and clinopyroxene together with rutile and quartz in the matrix represents a stage of the peak metamorphic conditions of the eclogite facies (T=600-650℃ and P>12-13kbar). Magnesio-hornblende, plagioclase, biotite and chlorite replace the garnets and clinopyroxenes, suggesting a retrograde metamorphic stage after the peak eclogitic conditions. Subhedral to anhedral magnesio-hornblendes containing eclogitic minerals such as garnet, clinopyroxene and rutile were probably formed during a prograde crystallization after eclogitic metamorphic conditions attained. Eclogites also occur in pelitic and granitic gneisses in the Aktyuz district, about 30km northeast of the Orobashy area. Despite differing modes of occurrence, the Orobashy and Aktyuz eclogites may have experienced similar metamorphic evolution.View full abstractDownload PDF (4426K) -
Yukio FUJIMOTO, Masatsugu YAMAMOTOArticle type: Article
2010 Volume 64 Issue 3 Pages 127-144
Published: May 25, 2010
Released on J-STAGE: May 16, 2017
JOURNAL OPEN ACCESSCretaceous granitic rocks in the Shirakami mountains, Northeast Japan occur as three small masses namely the Nanatsudaki, Osawagawa, and Hishibamiyama masses and large Shirakamidake composite mass subdivided into the east, central, and west bodies. These masses are composed of mainly granodiorite, associated with granite and tonalite. In the Shirakamidake composite mass, central granitic body intrudes to the east body and forms N-S direct mylonite zone with west body. East body has a dome but central body has a basin and west body forms northward opening basin accompanied by mylonite zone. Hishibamiyama tonalite, Shirakamidake east body and a part of Shirakamidake west body are classified into the magnetite series granitoid. Most of the granitic rocks show similar trends in SiO_2-variation diagrams except Hishibamiyama granodiorite which show higher A/CNK and SrI, suggesting magmatic contamination with original Hishibamiyama tonalitic magma and lower-crust materials. The Cretaceous granitic magmatism in the Shirakami mountains, occurred 110Ma (Rb-Sr whole rock isochron) to 89Ma (mineral K-Ar) formed Shirakamidake east, Shirakamidake west body, Nanatsudaki, Oosawagawa masses, and continued secondly 86Ma to 71Ma (biotite K-Ar) formed Hishibamiyama granodiorite. Moreover Shirakamidake central body cooled about 300℃ at 66Ma. Left-lateraly shear movement also simultaneously progressed from 92 to 66Ma accompanied by upheaval movement of Shirakamidake west body. Compiled radiometric ages show the Kitakami granites are 135-105Ma of each methods imply relatively rapid cooling but the Abukuma are 125-100Ma (Rb-Sr whole rock isochron) to 115-85Ma (biotite K-Ar) indicate slower. In the northern Kitakami, temporal variations of SrI increase gradually from II to IV zone. Same tendencies are recognized in the southern Kitakami (under 0.7045) and in the Abukuma (0.7047-0.7052) but the Asahi, Yamizo, Tsukuba increase higher. SrI of the Shirakami and the Taihei has similar range to those of the Abukuma granites. The εSrI-εNdI relationship show that the Cretaceous granitic rocks of Shirakami and Taihei mountains can be correlate to the Abukuma granites more clear.View full abstractDownload PDF (2613K)
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