All issues
Successor
Volume 59, Issue 1
Displaying 1-4 of 4 articles from this issue
- |<
- <
- 1
- >
- >|
-
Shohei Banno1968 Volume 59 Issue 1 Pages 1-8
Published: January 05, 1968
Released on J-STAGE: August 07, 2008
JOURNAL FREE ACCESSOn the basis of Fe2+-Mg partition between coehisting garnet and clinopyroxene of eclogites in the Higasi-akaisi peridotite mass, both from the Gongen valley and from the main adit of the Akaisi mine, it is suggested that the crystallization temperatnre of the eclogites in this peridotite mass corresponds to that of lower amphibolite fades. The temperature thus estimated appears to be higher than that of surrounding metabasites, and eclogites enclosed therein.
The chemical compositions of six pairs of gamet-clinopyroxene assemblage, including the new analyses of three pairs, are described in Table 1.View full abstractDownload PDF (444K) -
Hitoshi Onuki1968 Volume 59 Issue 1 Pages 9-20
Published: January 05, 1968
Released on J-STAGE: August 07, 2008
JOURNAL FREE ACCESSFrom the contact aureole of the Tono granitic mass, four almandine-bearing hornfelses are chemically studied. Almandine, biotite and cordierite, representing the main ferromagnesian phases, occur in all of the hornfelses. Four almandines, two biotites and four hornfelses are chemically analysed. Almandines have a range from (Alm82 Pyr9 Spes3 Gr5 And1) to (Alm83 Pyrll Spesl Gr4 Andl). Their compositions are possibly representative as pyralspite to occur in hornfelses belonging to the amphibolite facies. Although chemical data of the hornfelses do not allways satisfy the main compositional requirements proposed by Chinner (1962) for garnet development in hornfelses, this result is mainly based upon the discordance between apparent bulk analyses and real chemistry of garnet-bearing part of the hornfelses with big garnet porphyroblast. If chemical condition is suitable, almandine stably occurs even in hornfelses.View full abstractDownload PDF (591K) -
Yuzo Kato1968 Volume 59 Issue 1 Pages 21-39
Published: January 05, 1968
Released on J-STAGE: August 07, 2008
JOURNAL FREE ACCESSThe Kohu plutonic body which occurs as a semicircular outcrop in Kohu basin is one of the largest Tertiary granitic bodies in Japan. Its N-S elongation is 45km. and its E-W breadth is 30km. It traverses the boundary between the Shimanto Belt and the Fossa Magna.
The granitic rocks composing this plutonic body are divided into 10 types according to their occurrence, petrography, chemistry and mineralogy. These types are named: 1) Hirose, 2) Sanpo, 3) Shiodaira, 4) Yogai, 5) Tonogi, 6) Kanegawa, 7) Kurogane, 8) Ashigawa, 9) Mizugaki-Shosenkyo and 10) Huruyado. The first four types are granodiorite, carrying biotite and hornblende. The next three types are quartz-diorite, with hypersthene and c1inopyroxene (augite or salite). The Ashigawa type is a quartz-diorite without pyroxene. And the last two types are adamellite. These granitic rocks are associated with intrusions of andesite, quartz-porphyry and andesitic pyroclastic rock in the area.
New chemical analyses of 32 rock samples of these granitic rocks are given in Table 4. Their chemical compositions, except that of the Asigawa type, are generally similar to the Tertiary granitic rocks in the Green Tuff Region of northeastern Japan and the Shimanto Belt. The Ashigawa type is very low in K2O and high in Na2O and resembling the Tanzawa plutonic body.View full abstractDownload PDF (1230K) -
Hajime Takamura1968 Volume 59 Issue 1 Pages 40-47
Published: January 05, 1968
Released on J-STAGE: August 07, 2008
JOURNAL FREE ACCESSDownload PDF (519K)
- |<
- <
- 1
- >
- >|