| Autor: |
SAKAI, Hideo, HIRAI, Toru, SAWADA, Toyoaki, NAKAYAMA, Takeshi, WADA, Hiroo, MIKUMO, Takeshi |
| Jazyk: |
japonština |
| Rok vydání: |
1991 |
| Předmět: |
|
| Zdroj: |
京都大学防災研究所年報. B. 34(B-1):339-350 |
| ISSN: |
0386-412X |
| Popis: |
Electro-magnetic studies have been conducted to investigate the volcanic activity of Mt. Yakedake locating in the Norikura volcanic chain in central Japan. Preliminary results were obtained as follows;1. The measurement was made on the total magnetic force and the surface resistivity at the Shiramizudani area, the half up of Mt. Yakedake. The analitical results obtained elucidate the spatial distribution of both volcanic sediments and mud flow deposits around this area.2. The paleomagnetic method was developed to investigate the temperature conditions when the volcanic sediments were embeded. The method was applied to classify the volcanic sediments (originated from Nakao pyroclastic flow c.a. 2500 to 1500 years B.P.) into three types; pyroclastic flow deposit, hot lahar deposit and cold lahar deposit.3. Three observatory stations were established for the continuous monitoring of electric self-potential, geomagnetic total force, ground temperature and steam temperature conditions around the Yakedake area. Preliminary data observed at Nakao Station, the foot of Mt. Yakedake, show that the short-term fluctuations of the electric potential correlate quite well with these of the temperature changes of steam rising from 300 m depth. During the period of the above fluctuation, small earthquakes were observed around the Yakedake area in most cases. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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