1989 Fiscal Year Final Research Report Summary
The third geophysical survey of Nyiragongo which lava lake appeared on June 21, 1982.
| Project/Area Number |
63041012
|
|---|
| Research Category |
Grant-in-Aid for Overseas Scientific Survey.
|
| Allocation Type | Single-year Grants |
|---|
| Section | Field Research |
|---|
| Research Institution | Hirosaki University |
|---|
Principal Investigator |
TANAKA Kazuo Professor, Faculty of Science, Hirosaki University, 理学部, 教授 (40003511)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HAYASHI Shintaro Associate Professor, Faculty of Education, Akita University, 教育学部, 助教授 (90180968)
SETO Masahiro Professor, Tohoku Institute of Technology, 工学部, 教授 (60085412)
HAMAGUCHI Hiroyuki Professor, Faculty of Science, Tohoku University, 理学部, 教授 (20004385)
KASAHARA Minoru Research Associate, Faculty of Science, Hokkaido University, 理学部, 助手 (40001846)
|
|---|
| Project Period (FY) |
1988 – 1989
|
| Keywords | Rift Valley of Africa / Active Volcano / Lava Lake / Eruption / Volcanic Earthquake / Geothermal Structure / Volcanic Rock / Magma |
|---|
| Research Abstract |
The results obtained by the third geophysical survey in Virunga volcanic region, Zaire, are summarized as follows. (1) The lava lake of Nyiragongo was observed to increase in amount of furmarole without temperature change. (2) Seismic activity in 1988 was high at the southeast of Nyamuragira crater, where new eruptions took place in April, 1989. (3) The expansion of Nyamuragira crater reached to a value of 1x10^<-4> in strain after the 1989 eruption. (4) By the magneto-telluric method, a high conductive area being interpreted as partial melting part was found to be along a narrow zone of old eruption places. (5) Aphyric type elements of ejecta from the 1975-1989 Nyamuragira eruptions changed to mafic with time, increasing in amount of MgO, CaO and decreasing in K_2O and Na_2O.
|
