789: J. Hot Spring Sci. /2 -*,ῌ-*3 ,**3ῌ῍

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Geological and Geochemical Study on Natural Gas
Resources of Dissolved-in-Water Type Beneath
the Kanto Plain (Minami-Kanto Gas Field) :Outcome as Guidelines for Development of Hot Springs,
Use of Deep-Seated Geothermal Water, etc.
Takayuki SAWAKI+, Nobuyuki KANEKO+, Shun-ichiro IGARI+,Tatsuo MAEKAWA+, Shuichi TOKUHASHI+, Takeshi NAKAJIMA+,Manabu TANAHASHI+, Susumu SAKATA+ and Sumito MORITA+ ,

Abstract
The Minami-Kanto gas ﬁeld is the largest natural gas deposit of dissolved-in-watertype in Japan. However, geological information on the gas ﬁeld has not been updated
since +310. So, the new research project “Geological and geochemical study on naturalgas resources of dissolved-in-water type beneath the Kanto Plain (Minami-Kanto gasﬁeld)” has begun in FY ,**2. In the project, the authors are getting the geological andgeochemical data on the origin and distribution of the natural gas, and undergroundgeological structures in and around the ﬁeld. The collected data will be integrated andpublished as a new fuel resource geological map that will include the latest geologicalinformation of the Kanto region. The authors expect that results of the study will beused as basic information for estimation of geo-resources in Japan, and that the integrated geo-information will lead to outcomes as guidelines for safe and e#ective development of natural gas resources and deep-seated geothermal water, and global warming mitigation measures for methane.
+ -*/ῌ2/01!"#$%&' +ῌ+ῌ+ #$%()* 1 + + National Institute of Advanced Industrial Science and Technology (AIST), Institute for Geo-Resources and Environment (GREEN), AIST Tsukuba Central 1, +ῌ+, Higashi-+,
Tsukuba, Ibaraki -*/ῌ2/01, Japan.
,,- ./0123456 , AIST, Geoinformation Center.

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Key words : Minami-Kanto gas ﬁeld, natural gas resources of dissolved-in-water type,deep-seated geothermal water, guidelines for development of hot springs,
updating of geological information.

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GSJ : Geological Survey of Japan.
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