1992 Fiscal Year Final Research Report Summary
Geomagnetic Survey of the Active Fault by Means of the Anchored Balloon Magnetometer
| Project/Area Number |
03452058
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
固体地球物理学
|
|---|
| Research Institution | Tottori University |
|---|
Principal Investigator |
MIYAKOSHI Jun'ichiro Faculty of General Education, Tottori University, Professor, 教養部, 教授 (60032116)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OSHIMAN Naoto Disaster Prev.Res.Inst.,Kyoto Univ., Assistant Professor, 防災研究所, 助教授 (70185255)
OKADA Shomei Faculty of Education, Tottori University, Assistant Professor, 教育学部, 助教授 (70093581)
SHIOZAKI Ichiro Faculty of General Education, Tottori University, Assistant Professor, 教養部, 助教授 (80221290)
NISHIDA Ryohei Faculty of General Education, Tottori University, Professor, 教養部, 教授 (90027269)
|
|---|
| Project Period (FY) |
1991 – 1992
|
| Keywords | Active Fault / Magnetic Anomaly / Underground Structure / Geological Dyke / Total Force / 2-D Structure / Anchored Balloon / Vertical Gradient |
|---|
| Research Abstract |
Measurements of the vertical profiles of the geomagnetic total intensity were conducted upon the geomagnetic anomalies of two dimensional pattern which observed on the Yoshioka active fault (1943 Tottori Earthquake, M=7.4) The objective of the measurements is to construct the under-ground structural model more precisely for the source of the 2-D pattern magnetic anomalies observed on an active fault. Intensities of geomagnetic total force were measured at various heights from 5 to 100 m using the proton-magnetometer, of which the sensor was hanged by an anchored balloon.
Geomagnetic total force upon the positive magnetic anomaly of 2-D structural pattern was found to decrease gradually to an almost constant value at the height of about 100 m. On the other hand, upon the negative magnetic anomaly, it decreases gradually to an almost constant value at the height of about 100 m.
Taking results of these measurements into consideration, the source of the 2-D pattern magnetic anomalies observed on the Yoshioka active fault was explained as an underground magnetic dyke with the magneticsusceptibility of 2.9 x 10^<-3> e.m.u. of 68.4 m thickness inclined towards north by 116ﾟ. The top of the dyke is at the depth of 11.9 m beaneath the fault.
|
Research Products
(2 results)
