Grant-in-Aid for International Scientific Research.
|Section||Joint Research .|
|Research Institution||KYUSHU UNIVERSITY|
EHARA Sachiko FAC.ENG., KYUSHU UNIV.PROFESSOR, 工学部, 教授 (10002346)
許 恵平 中国長春地質学院, 地物系, 副教授
張 良懐 中国吉林省, 地震局, 教授
金 旭 中国長春科技大学, 地物系, 教授
ITOI Ryuuichi FAC.ENG., KYUSHU UNIV., ASSOC.PROF., 工学部, 助教授 (50108768)
WATANABE Koichiro FAC.ENG., KYUSHU UNIV., ASSOC.PROF., 工学部, 助教授 (10182916)
MOGI Tohru FAC.ENG., KYUSHU UNIV., RESEARCH ASSOC., 工学部, 助手 (80182161)
FUJIMITSU Yasuhiro FAC.ENG., KYUSHU UNIV., ASSOC.PROF., 工学部, 助教授 (10264095)
JIN Xu CHANGCHUN UNIV.OF EARTH SCIENCE,PROF.
|Project Fiscal Year
1996 – 1997
Completed(Fiscal Year 1997)
|Budget Amount *help
¥5,800,000 (Direct Cost : ¥5,800,000)
Fiscal Year 1997 : ¥2,900,000 (Direct Cost : ¥2,900,000)
Fiscal Year 1996 : ¥2,900,000 (Direct Cost : ¥2,900,000)
|Keywords||Geothermal fields / Geothermal systems / Volcanoes / Basalt / Geothermal survey / Changbaishan volcano / 地熱地域 / 地熱系 / 火山 / 玄武岩 / 地熱調査 / 長白山火山|
In this study we clarified the geothermal systems associated with basaltic volcanoes in the northeastern part of China. The main results are shown below :
1.From the study of heat flow distribution in the northeastern part of China, it is clarified that the basaltic magmas begin to occur at a depth of 70km to 150km, that is, not in the crust but in the upper mantle. Such deep generation of basaltic magma does not develop geothermal systems in the region generally.
2.From the study of thermal history based on the fission track dating of granitic rocks, it is clarified that the crust have not experienced so high temperature state since about 100Ma.
3.An active geothermal system develops on the flank of Changbaishan volcano at the border of China and North Korea and it is maintained by mixing of magmatic fluids and meteoric water. The magmatic fluids are derived from not basaltic magmas but trachytic magmas which are formed by remelting of the crust by basaltic intrusions. The trachytic magmas assumed in the shallow crust, that is, about 8 km deep.
4.Small geothermal systems develop in the Quaternary basaltic volcanic region at the border of China and Mongolia. But these geothermal systems are not formed by mixing of magmatic flluids and meteoric water.
They are formed only by heating of deeply penetrated meteoric water.
5.There are no geothermal systems in the Quaternar basaltic volcanic region at the border of China and Russia.
Form the above results, we can conclude that geothermal systems are not developped by basaltic magmas generally. However, if basaltic intrusions heat the shallow crust and generate silicic magmas in the shallow crust, geothermal systems can develop in the basaltic volcanic region.