Bulletin of the Geological Survey of Japan Vol.52 No.1 (2001)

Cover photograh | Table of Contents |

Cover photograh

Fossil Crassostrea gigas reef at the middle Pleistocene Shimosa Group in Kasumigaura Town, Ibaraki

This exposure of the reef is extended for about 5m in height and 70m in width. Indigenous shells of Crassostrea are observed in gregarious vertical position called relay strategy which dead shells of earlier generations offer the basis for the attachment of later generations． However, almost shells of Crassostrea are concentrated parallel to the bedding by tidal and wave currents.

(Photoed by Rei NAKASHIMA; Institute of Geoscience, University of Tsukuba)

Table of Contents

Title	Author	PDF
Methane migration from the Nankai Trough accretionary prism	Tomohiro TOKI, Toshitaka GAMO, Toshiro YAMANAKA, Jun-ichiro ISHIBASHI, Urumu TSUNOGAI and Osamu MATSUBAYASHI ( 1-8)	52-01_01.pdf(900KB)
Elemental distribution in the volcanic ash soils from the Kanto District, Japan: Preliminary study for the soil geochemical mapping	Shigeru TERASHIMA, Noboru IMAI and Takashi OKAI ( 9-40)	52-01_02.pdf(4,146KB)
Molluscan fossil found from pyroclastics of the Niijima volcano and its basement rocks	Ichiyo ISOBE and Rei NAKASHIMA (41-48)	52-01_03.pdf(3,291KB)
Abstracts for Geological Survey Seminar No. 270 Poster session of the new geological maps published by GSJ	(49-55)	52-01_04.pdf(968KB)
Abstracts for Geological Survey Seminar No. 271 Studies of seismogenic zone of inland earthquakes Material science and modeling of earthquake process	(57-70)	52-01_05.pdf(1,959KB)