Trans Korean Peninsula-Japanese Islands Seismic Observation
Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||Faculty of Science, Kyoto University|
OIKE Kazuo Faculty of Science, Kyoto University, 理学部, 教授 (40027248)
全 明純 韓国資源研究所, 研究員
KIM Sungkyun College of Natural Sciences, Chonnnam National University, 総合人間学部, 助教授
OKADA Atsumasa Faculty of Science, Kyoto University, 理学部, 教授 (90086174)
SHIMIZU Hiroshi Faculty of Science, Kyushu University, 理学部, 助教授 (50178985)
ISHIHARA Yasushi Faculty of Science, Yokohama City University, 文理学部, 助手 (40232334)
FURUMOTO Muneyoshi Faculty of Science, kanazawa University, 理学部, 助教授 (80109264)
YAMADA Isao Faculty of Science, Nagoya University, 理学部, 助教授 (60022670)
FUKAO Yoshio Faculty of Science, Nagoya University, 理学部, 教授 (10022708)
OHKURA Takahiro Faculty of Integrated Human Studies,Kyoto University, 総合人間学部, 助手 (40233077)
SHIBUTANI Takuo Disaster Prevention Research Institute, Kyoto University, 防災研究所, 助手 (70187417)
ANDO Masataka Disaster Prevention Research Institute, Kyoto University, 防災研究所, 教授 (80027292)
JUN Myungsoon Korea Institute of Geology, Mining and Materials
鄭 承桓 韓国動力資源研究所, 研究員
鄭 富興 韓国動力資源研究所, 研究員
|Project Period (FY)
1990 – 1992
Completed(Fiscal Year 1992)
|Budget Amount *help
¥14,000,000 (Direct Cost : ¥14,000,000)
Fiscal Year 1992 : ¥5,000,000 (Direct Cost : ¥5,000,000)
Fiscal Year 1991 : ¥5,000,000 (Direct Cost : ¥5,000,000)
Fiscal Year 1990 : ¥4,000,000 (Direct Cost : ¥4,000,000)
|Keywords||Korea Peninsula / Seismicity / Active Fault / Broad-band Seismograph / Pohang Seismic Station / Microearthquake / Yansan Fault / 日本列島 / 梁山断層 / 地震観測 / Yansan fault / 日本海 / 地球内部構造|
1.Seismological Nature in and around Korea Four plates are converging in East Asia where there are many large active faults and tectonic belts which generate large earthquakes. Recent seismicity in the Korea region is very low but historical records of Korean peninsula show that there occurred many large earthquakes including some disastrous ones. There are many fault systems in Korea peninsula. We must study that there are some active faults omong them or not.
2.Purposes and plannings of project One of main purposes of this project is to establish a permanent seismic observation station of very broad band seismograph in Pohang. Another one is to observe microearthquake activity-in the Yansan fault region. In the second purpose we aimed to know the seismic activity in the region. to get some records of distant earthquakes and to get some records of deep earthquakes. By such observations we can analyze structures of the crust and upper mantle in the region and can study the crustal stres
s state in the Korea region. Then we can compile these data with those in the other wide regions in East Asia.
3.Results and further problems From very broad band seismic records at Pohang we have analyzed Reiley waves to determine the dispersion characteristics of group velocity. The results show that there is a low velocity region in the upper mantle beneath the Ryukyu basin. This result is an example showing that the Pohang station is an important station for seismology in East Asia.
Temporary observation network of high sensitive seismometers for the study of microearthquakes was made in the Yansan fault region from 7th July 1993 to 20th August 1993. This observation was the second joint observation in the region. We have gotten many kinds of records by these observations. Several natural earthquakes in the Yansan fault region and many artificial explosions were recorded. This means that Yansan fault system is active fault which can generate big earthquakes in the future.
Some large events in Japan with magnitudes larger than six could be recorded by the network. We are now analyzing the velocity structure using such records.
Geomorphological study has also been done in the Yansan fault region. We have made a trench across the fault and discovered the clear evidenses indicating that there occurred holizontal dislocations along the fault during last 200 to 300 thousands years. The Yansan fault is the first active fault in Korea of which we found the clear evidences.
It is necessary to establish permanent seismograph network to study the detailed natures of the seismic activity of this fault. And it is necessary to make geomorphological surveys in various regions along the fault to study the reccurrence time and slip rate of the fault. They are very important for the long term prediction of earthquakes in the region. Less
Research Output (13results)