Bulletin of the Geological Survey of Japan Vol.49 No.10 (1998)

Cover photograh | Table of Contents |

Cover photograh


Estimated distribution of natural methane gas hydrate around Japan

Nankai Trough, Choshi spur, Kuril Trench, eastern margin of Japan Sea, southern margin of Okhotsk Sea are the estimated distribution areas of natural methane gas hydrate. They are mapped through the distribution of BSR (Bottom Simulating Reflector) on the reflection seismic profiles. Hydrate sample was cored at ODP Site 808 on Okushiri Ridge, eastern margin of Japan Sea and hydrate containing layer was confirmed in Nankai Trough at ODP Site 796 through the use of anomalous low chloride concentration of the interstitial water. Distribution data of Sato et al. (1996) was plotted with NOAA ETOPO 5 topographic database using GMT (Generic Mapping Tools; Wessel and Smith, 1991).

(Photoed by Manabu TANAHASHI)

Table of Contents

Special Issue:Research on gas hydrate

Research on gas hydrate-Preface Yoshihisa OKUDA (493) 49-10_01.pdf(141KB)
Introduction to exploration research on gas hydrates in Japan Yoshihisa OKUDA (494-500) 49-10_02.pdf(1,054KB)
Equilibrium conditions of gas hydrate from mixtures of methane and ethane and outline of experimental apparatus for gas hydrate synthesis in porous sediment Tatsuo MAEKAWA (501-507) 49-10_03.pdf(909KB)
Nature of methane gas hydrate BSR from elastic wave simulations Shin'ichi KURAMOTO (509-516) 49-10_04.pdf(2,550KB)
Composition and stability of hydrates with double guests Toshiharu OKUI, Yuriko MAEDA and Ryozo HIRAOKA (517-526) 49-10_05.pdf(1,335KB)
Generation and accumulation models of natural gas hydrates Amane WASEDA and Takashi UCHIDA (527-539) 49-10_06.pdf(1,875KB)
Heat flow measurement as an exploration tool for subbottom methane hydrates Osamu MATSUBAYASHI (541-549) 49-10_07.pdf(1,156KB)