岩石鉱物鉱床学会誌

浜益玄武岩類の岩石学的研究

大場与志男, 田上滋

1966 年 56 巻 6 号 p. 235-245
発行日: 1966/12/05
公開日: 2008/08/07

DOIhttps://doi.org/10.2465/ganko1941.56.235

ジャーナルフリー

抄録を表示する抄録を非表示にする

Various kind of basalts of the Pliocene age are developed in the western extremity of the so-called “Kabato mountainland” in central Hokkaido.
In this area, voluminous andesitic lavas and pyroclastic rocks are predominant in Miocene to Pliocene age, and normal sedimentary rocks are very limited in distribution.
The basalts occur as lava flows, covering the Miocene and Pliocene formations, or as dikes, cutting them.
The basalts can be divided into the following three types on the basis of the petrographic characters;
A type: Olivine basalt (IIIb, IIIb→c)
Augite-olivine basalt (IVb, IVb→c)
B type: Olivine basalt (IIIc)
Augite-olivine basalt (IVc)
Augite basalt (Xc)
Olivine-augite basaltic andesite (IVc)
C type: Olivine basalt (IIIa→d, IIId)
Olivine-augite basalt (IVa→d, IVd)
Among them, C type basalts noteworthy include holocrystalline xenoliths and xenocrysts of plagioclase, quartz and hornblende.
The present study clarified that the basalts of this area are presumably generated from the alkali basalt magma; A and B type basalts are derived solely by the fractional crystallization, whereas C type basalts which compose the majority of the basalts, are produced under the influences of contamination of the magma with salic rocks of the basement.

抄録全体を表示

PDF形式でダウンロード (648K)
共存する角閃石とCaに富んだ輝石との間のMg-Fe⁺²の分配

大貫仁

1966 年 56 巻 6 号 p. 246-255
発行日: 1966/12/05
公開日: 2008/08/07

DOIhttps://doi.org/10.2465/ganko1941.56.246

ジャーナルフリー

抄録を表示する抄録を非表示にする

理論的な考察ののちに,各種岩石中に平衡に共存する角閃石とCaに富んだ輝石間のMg-Fe⁺²の配分について調べた。両鉱物間のMg-Fe⁺²の分配係数はそれらの生成時の温度と共に増大する。この分配係数の温度による変化図を推定し,分配係数がひとつの地質学的温度計として使用出来ることについて述べた。

抄録全体を表示

PDF形式でダウンロード (454K)
島根県加茂町附近の花崗岩類とその崩壊について(I)

三浦清

1966 年 56 巻 6 号 p. 256-283
発行日: 1966/12/05
公開日: 2008/08/07

DOIhttps://doi.org/10.2465/ganko1941.56.256

ジャーナルフリー

抄録を表示する抄録を非表示にする

The geology, petrographic characters of the granites, and the types of collapses of the rocks caused by heavy rain fall in the Kamo District, Shimane Prefecture, are described to clarify the relation between rock types and collapsing phenomena in the granite mountain area.
The granitic rocks comprise granodiorite and biotite granite, and both are weathered remarkably in most parts. From the genetic point of view, the collapses are classified into six types.
1) Collapse, closely related to the joint structure of the rocks; they occur characteristically at the foot of slopes in the region of weathered granodiorite.
2) Collapse of the weathered zone (uppermost layer covered with vegetation) of slopes, caused by difference of physical properties to the ground water between the weathered zone and the basement rocks.
3) Collapse with characters of (1) and (2).
4) Collapse closely related with dikes in granite.
5) Collapse accompanying landslide in fault breccia zones.
6) Collapse or resliding of the talus deposit, made by an older land slide of the adjoining rock masses.
The majority of the collapses in this district belong to types (1), (2) and (3). Types (1) and (2) predominate in granodiorite and (3) in biotite granite.

抄録全体を表示

PDF形式でダウンロード (2869K)

J-STAGEへの登録はこちら（無料）