γ-線の測定 -花折断層-

Abstract

The γ-ray survey was carried out by a scintillation survey meter at O-hara area near aroundHanaore Fault Zone in the northern part of Kyoto. The survey was done several times over alongthe same observational line. Static pattern of γ-ray intensity is revealed similar one in each other, even there is small difference.Strong intensity of γ-ray means subsistance of crushed rocks zone and a huge fault as Hanaoreconsists of the structure made by these weak zones. A pretty large earthquake among micro-earthquakes was occurred, fortunately for us, during survey period. The γ-ray survey was donejust on January 6, 1978 when it was just one day before the earthquake.The observational results before the earthquake, did not give large variations of γ-ray in-tensity. But after 5 days from the earthquake, that is January 11, the intensity of γ-ray decreasesinto low value, over observational error, at almost all stations. The improvement of γ-ray wasfound after 2 weeks from the earthquake.Ordinarily the large fault as Hanaore is one of boundaries around block of crust, and faultzone is more sensitive to geophysical activity in the crust.Continuous observation of γ-ray will give the solution to corelation with earthquake or earth-quake prediction.