All issues
Volume 48 (2007 - 200･･･
- Issue 6 Pages 285-
- Issue 5 Pages 232-
- Issue 4 Pages 162-
- Issue 3 Pages 116-
- Issue 2 Pages 66-
- Issue 1 Pages 2-
Volume 48, Issue 5
Displaying 1-5 of 5 articles from this issue
- |<
- <
- 1
- >
- >|
-
Hajime TANAKA, Takuya YAMADA, Shuichiro YOKOTA, Shigeyuki SUZUKI2007 Volume 48 Issue 5 Pages 232-240
Published: December 10, 2007
Released on J-STAGE: March 26, 2010
JOURNAL FREE ACCESSThe Triassic Nariwa Group is composed of consolidated rocks of marine to non-marine deposits. The Nariwa Landslides which have low angle slip surface with slow displacement velocity are characterized by the slip surface in a coaly bed in non-marine successions. The Nariwa Group is affected by folding and open cylindrical folded structures are formed. The aim of this paper is to study an effect of geological structure to form landslide. Detail observations of landslide distribution and analysis of the structures of landslide mass have been carried out in the Yasunari Landslide Area of Kawakami Town, Okayama Prefecture. Structural analysis of folds of the Nariwa Group is also precisely studied in this area. The landslide which distributed in the area of hinge of syncline structure was found. The direction of mass movement fits with that of fold axis of the syncline. The shape of the main slip surface is similar to the folded structure representing that the landslide is controlled by the pre-existing folded structure.View full abstractDownload PDF (2926K) -
in the Case of Fugoppe National Designated Historic Site in Yoichi Town, HokkaidoTadashi YASUDA, Hiromitsu YAMAGISHI, Toshiaki ASANO2007 Volume 48 Issue 5 Pages 241-252
Published: December 10, 2007
Released on J-STAGE: March 26, 2010
JOURNAL FREE ACCESSThe Fugoppe Cave is located at Maruyama Hill, Yoichi Beach, Hokkaido, Japan, and is designated as a National Cultural Heritage. The Cave has very unique engraved rock arts on rock walls, which are known to have been sculptured ca. 1, 600 y. B. P. The rock arts of walls were discovered in 1950 by high school student. The engraved walls of Fugoppe Cave have been weathered and occurred separation on the walls. As a result, the rock arts such as human bodies and boats, have become obscure. Furthermore attention has been called to be afraid of rock fall from the walls, because many cracks have been appearing on the wall. These factors have led to perform engineering geological investigations. The contents of the investigations were to obtain fundamental data, such as detailed topographic photo images of quadrangle grids. Based on the photographic images, we evaluated the possibility of rock fall and wall separation from engineering geological point of view. These engineering geological investigations can be useful and may become a standard sample for conservation of prehistoric site, such as rock arts, and stone images of Buddha, not only in Japan but also in the world.View full abstractDownload PDF (6370K) -
Manabu TAKAHASHI, Syou FUJINO, Takato TAKEMURA, Yoko MICHIGUCHI2007 Volume 48 Issue 5 Pages 253-257
Published: December 10, 2007
Released on J-STAGE: March 26, 2010
JOURNAL FREE ACCESSTo visualize in detail the manner of deformation in rocks under various confining and pore pressures, we used a micro focus X-ray CT system to obtain three dimensional image with high resolution of 5 micron. A new pressure vessel was developed to simultaneously supply both confining pressure and pore pressure to rock specimen. Berea sandstone and Noto diatomecious mudstone specimen of 10mm diameter and 20mm length were deformed hydrostatically. The diameters at every 15 degree angle were measured under the various conditions of confining and pore pressures. The average diameter decreased monotonically with increasing effective confining pressure, following the law of effective confining pressure. Sensitive orientation around the specimen diameter during pressurization was recognized, deformation anisotropy under pressurization then emerged and the fluctuation of diameter reached a maximum value of 8% in the case of Noto diatomecious mudstone. In this paper, we demonstrated deformation measurements by means ofmicro focus X-ray CT. This measurement method is applicable for deformation measurements of small and irregular rock specimen under various confining and pore pressures.View full abstractDownload PDF (1206K) -
Yukiyasu FUJII, Kunio WATANABE, Kazuya MURAKAMI2007 Volume 48 Issue 5 Pages 258-264
Published: December 10, 2007
Released on J-STAGE: March 26, 2010
JOURNAL FREE ACCESSThe restoration and conservation activities have been carrying out for the preservation of the Buddhist Monastry of Ajina Tepa, heritage of the ancient Silk Roads in Tajikistan. This project is managed by UNESCO and financially supported by the Japanese Funds-in-Trust for the preservation of cultural heritage. The site documentation was carried out as one of the activities for the year 2006. 3-D visualization of heavily damaged walls and topographical mapping of the site was done by the application of photogrammetric technique. Consequently, this technique was practicably useful for the documentation and the planning for the restoration of the site. From the objective results of 3-D visualization, it was clarified how much damaged those walls were. Therefore, it can estimate the risk for the walls to break down. High resolution topographic map will be utilized for the planning of the site restoration.View full abstractDownload PDF (3064K) -
Hideki INAGAKI, Hiroyuki OHNO2007 Volume 48 Issue 5 Pages 265-272
Published: December 10, 2007
Released on J-STAGE: March 25, 2010
JOURNAL FREE ACCESSThe environmental disruption by a disaster occurs in all over the world. The disaster is divided into human disaster and natural disaster. For the environmental disruption, there are social environmental destruction and natural environmental one. The mitigation for the disaster is one of the big themes of applied geology. However, there are few articles at a point of view of the environmental disruption due to the disaster. The authors performed case studies such as deforestation and soil erosion in mountainous district and the flooding in downstream area caused by Kanna nagashi, which is one of the human disasters as relating to a geological feature.
On the other hand, there is the destruction of social environment and natural environment by the natural disaster such as a volcanic eruption, an earthquake and a heavy rainfall. In this paper, we describe the deforestation due to the volcanic eruption of Miyake-jima in 2000 and the environmental deterioration of forest vegetation and the debris outflow induced by Niigataken Chuetsu earthquake in 2004.
The maintenance of natural environments tends to deal after a disaster occurred, but it is important to make the slope healthy before the collapse through well keeping of the root of tree, as like a preventive medicine. At that time, the total cohesive strength method by Inagaki is available to stability of the slope ground concerning to the root system of plants.View full abstractDownload PDF (4924K)
- |<
- <
- 1
- >
- >|