公益財団法人深田地質研究所年報 第12号 2011

The candidate for a position of professor nominated by Department was rejected by Faculty meeting - The case of personnel at the Department of Geology in the Faculty of Science, Kyoto University –
キーワード: 教授人事,京都大学理学部,地質学鉱物学教室,教授会,大学自治
Abstract: As for personnel affairs of the faculty staffs in the Faculty of Science of Kyoto University, the Dean of the Faculty of Science accepts applications for the said post. Accordingly, the Chairman of the Department possessing the post recommends the candidate nominated by the faculty meeting of the Department. In almost all the cases, the candidate recommended by the Chairman is solely accepted. The Faculty Meeting examines the candidate. When the Meeting approves the candidate, the personnel affair is decided. Nearly 40 years ago, the candidate for the post of professor recommended by the Chairman of the Department of Geology was denied by the Faculty Meeting of Science and the other candidate recommended by the professor of another university other than Kyoto University was approved instead. The Departmental intention has been denied but a few faculty staffs of the Department accepted the decision given by the Faculty Meeting. Many of the professors of the Faculty of Science except for the Department of Geology were deeply impressed the personnel affair for a Geological professor as a matter of self-government of Kyoto University. Most of the professors concerned about the matter have been passed away. A few professors concerned are still alive and asked about the real facts of the case. The events are left here on record.
Keywords: Personnel of Professor, Faculty of Science of Kyoto University, Department of Geology and Mineralogy, Faculty Meeting, Self-government of university
p. 1-13
A long long way to an international symposium on submarine landslides -We have made IGCP-585 5th International Symposium on Submarine Mass Movements and Their Consequences along this way-
Abstract: In this paper, I show a process to make an international symposium on submarine landslides from 24 to 26 October 2011, and a development process on submarine landslide studies in Japan. This symposium is associated with IGCP-585 called as E-MARSHAL of a submarine landslide program, which is a cooperation program between UNESCO and IUGS. This program is a continuous program from IGCP-511, and they have be held a international symposium on once for two years about these programs. In 2011, we are held on Kyoto University. I describe a long way to an international symposium on submarine landslides in Kyoto University in 2011.
Keywords: IGCP-585, submarine landslide, submarine mass movement, secretariat, Kyoto University, Bremen University
p. 15-24
作って楽しむウキウキアンモナイト -アンモナイト型の浮沈子を用いた地学教育の試み-
Let us make and enjoy Uki-uki Ammonites:Dissemination of earth science through self-learning practice of Cartesian Diver-making of Ammonites
Abstract: Fukada Geological Institute has been holding an open house event every October since 1997. This event aims at the strengthening the relation with community and also at the dissemination of the geological and geo-engineering knowledge to the public. Especially, experience of model-making of fossils as known by the name of ammonite accessory is highly appreciated (Fujita and Kawamura, 2007). In addition, to know ammonite biology more, it was reached the idea reproduction of ammonites swimming by combination of a cartesian diver and a model-making of ammonite. This is useful for attracting the people’s interest to the world of natural sciences. In this paper, it will be explained how to make the cartesian diver from the ammonite (Uki-uki ammonite in Japanese).
Keywords: Uki-uki ammonites, model-making of fossils, cartesian divers, dissemination of earth science teaching
Some cymatoceratids from the Lower Cretaceous Miyako Group, Iwate Prefecture, Japan
OBATA Ikuwo and MATSUKAWA Masaki
Abstract: Cymatoceras cf. neocomiense (Orbigny) from the Aptian and Albian strata of the Miyako Group, Iwate Prefecture, Japan and Cymatoceras aff. pseudoatlas (Yabe and Shimizu) from the Albian of the same group are described. Lower Cretaceous cymatoceratids from Japan are listed. Some comments are also provided on the Paleogene species from Japan. A modified figure of the presumed phylogeny of the Nautilidae (Matsumoto, 1984) is shown. Some differences of mode of life between nautiloids and ammonoids are noted and discussed in connection with the worldwide distribution and the mass extinction of ammonoids.
Keywords: Aptian, Albian, nautiloids, Cymatoceras, Miyako Group, Japan, phylogeny, mode of life
ソレアイト質マグマに由来する箱根火山のカルクアルカリ岩 - 輝石地質温度計によるマグマの温度解析 -
Calc-alkali rocks derived from tholeiite magma in Hakone volcano – Pyroxene geothermometry to estimate the magma temperature –
ISHII Teruaki
要旨:カルクアルカリ岩成因論は常に島弧の火成岩岩石学の重要な検討課題の一つであり,成因モデル(例えば,久野, 1953; Osborn, 1959; Sakuyama, 1981; 巽, 2011等)は多岐に渡っており,成因を議論するには,注意深い岩石学的解析が求められる.ここでは箱根火山中央火口丘産カルクアルカリ岩の,輝石晶出経路および輝石温度計で求めたマグマの温度変化を解析しその成因を検討した.初生的な島弧ソレアイト質高温マグマ(約1120℃)が,水に関し閉じたマグマ溜りで結晶分化して生じた低温マグマ(約970℃)が,元の高温マグマとマグマ混合しカルクアルカリ岩を形成したという,作業仮説を提出する.斑晶ステージの低温マグマの存在が鍵と成る.
Abstract: Calc-alkali rocks are widely distributed in the island arcs. The several models of their magma-genesis were proposed by many geoscientists (e.g. Kuno 1953, Osborn 1959, Sakuyama 1981, Tatsumi 2011) on the bases of precise petrological investigations. On the bases of the detailed analyses of the pyroxene crystallization sequences as well as estimated magmatic temperatures using pyroxene geothermometer, for calc-alkali rocks from the Central Cone (CC) in the Hakone volcano, the author suggest the following working hypothesis, i.e. those calc-alkali rocks are induced by magma mixing between low temperature magma (about 970℃), originated from fractional crystallization of the primitive high temperature (about 1120℃) hydras island-arc tholeiite magma within magma reservoir closed for water, and the high temperature magma. Low temperature magma in phenocryst stage is the key concept.
Keywords: Hakone volcano, pyroxene geothermometer, calc-alkali magma, island-arc tholeiite magma, magmatic temperature
Numerical Analysis of Geological Information using Scilab
FUJII Yukiyasu
Abstract: Scilab is the free software for numerical computation providing a powerful computing environment for engineering and scientific applications. Two attempts, which are related to data analysis and visualization of 3-D information gained by photogrammetry, are introduced here. One is calculations of fracture roughness with the best fit planes and translation to grid data. Second is visualization of topographic difference by fill dam shaking test.
Keywords: photogrammetry, 3-D points, data analysis, visualization
花崗岩地域の地すべり・地すべり地形 —その1 近畿から九州までの地域について
Landslides and landslide topography in granitic rock areas —Part 1:Kinki to Kyushu areas
大八木規夫・清水文健・井口 隆・内山庄一郎
OYAGI Norio, SHIMIZU Fumitake, INOKUCHI Takashi and UCHIYAMA Shoichiro
Abstract: Landslides in areas composed of granitic rocks are usually thought of shallow slides, such as slides of superficial soils, those of weathered zones (in 2 to 5 meters), debris deposits, and debris flows. However, we found a few but large landslides through out Japanese islands. Six examples, Unoike, Nishisami, Takama, Sekiya, Mizukoshi and Amitori landslide, in western Japan from Kinki to Kyushu, are described here and discussed on their characteristics and causes of those landslides. Five of them except Amitori landslide are similar to those of other sedimentary geologic bodies in morphology and structure. The Unoike landslide indicates a typical translational slide, the Nishisami and Takama shows multiple-type rotational slides. Sekiya landslide is a single-type rotational slide. Mizukoshi landslide is a composite of a rotational slide at the upper part of the slope and initial stages of slope deformations at the middle and lower parts. Amitori landslide is thought a unique type of landslide. It is composed of many slide blocks showing displacement forward and downward but with less or almost no rotation.
As an important static cause of those landslides can be considered that the structure of granitic rock bodies in those areas have closely spaced fracture (fault) systems in NE-SW and NW-SE strikes, and in some areas N-S and/or E-W in addition. Dynamic causes (triggers) may be earthquakes of fault-activation very close to those landslides.
Keywords: granitic rocks, landslides, landslide topography, fracture systems, Hino River, Kongo Mountains, Sefuri Mountains
A guide for elementary geomorphic analysis using “SuperMapGIS” (2)
キーワード: GIS, 数値標高モデル
Abstract: This is a guide for GIS beginners and describes the procedures and reminders about importing 10m-DEM (Digital Elevation Model) by Geospatial Information Authority of Japan into GIS, merging the data on GIS, and replacing altitude values. This guide is written for a user of the GIS software “SuperMapGIS”. However, this guide can also help people use other GIS software, because many operational procedures in it are similar with those of other popular GIS software.
Keywords: GIS, Digital Elevation Model
砂山の臨界状態と大崩壊の予測の試み ― 光弾性物質を用いた内部構造の解明 ―
Critical states of a sandpile and a trial to predict large avalanches ― An analysis of internal structure using a photo-elastic material ―
Abstract: Two-dimensional sandpile experiments using a photo-elastic material have been done in relation to predicting earthquakes. We took photos at many points of the experiments to observe the change in the internal structure of the sandpiles due to addition of particles. We tried to capture the characteristics of the structure before large avalanches in two different ways. The first one is the change between two successive photos. The results show that the change becomes rather smaller prior to large avalanches. The second one is the orientation of the stress chains near the surface of the sandpile which become parallel to the surface slope and very low angle prior to large avalanches. These are provisional results based on the analysis done so far. We need to further investigate in order to confirm the precursory conditions of large avalanches.
Keywords: photo-elasticity, gouge, stress chain, sandpile experiment
Study on rock physical interpretation of geophysical data for geotechnical applications (Part V) – Rock physics modeling of the compressive strength-seismic velocity relation of sedimentary rocks –
高橋 亨・田中莊一
Abstract: Estimating strength, especially compressive strength of rocks is one of major problems in many civil engineering applications. We have thus studied a rock physics model for estimating the compressive strength of sedimentary rocks from seismic velocity. Effective medium models are applied to the ultrasonic P-wave velocity in the laboratory and S-wave logging velocity with confined compressive strength measured in the tri-axial compression test, which are obtained for sedimentary rocks in Japan. The confined compressive strength – seismic velocity relation is modeled by combining two effective medium models for the confined compressive strength vs. porosity and seismic velocity vs. porosity. Applications of the model to two sets of actual measured data show good agreements between predicted and measured data, indicating that the compressive strength can be rationally predicted from seismic velocity using a rock physics model.
Keywords: rock physics, geophysics, seismic velocity, compressive strength, sedimentary rock
岩盤構造物の性能評価における課題について- 東日本大震災から学ぶこと ―
On the Performance Evaluation of Tunnel and Underground Cavern
Abstract: Author has been engaged in a lot of project constructing tunnels and underground caverns. Based on those experiences, the importance to evaluate the performance of underground structures was pointed out and the problems to be solved for the performance evaluation were discussed. Then it was suggested that asset management considering risk and aseismicity evaluation were useful and important. Also in order to do these, more discussions about aseismic design methodology were required. However, the Higashi-Nihon Great Disaster is an unprecedented disaster and showed that it is not enough to urge the problems vaguely. Here, the current state of the performance evaluation in the underground structures was reviewed, and the problems and future tasks were examined.
Keywords: underground structure, aseismic design, tunnel, underground cavern, high level radioactive waste disposal