和歌山市大浦観測室における地殻変動連続観測と和歌山市基線網における光波測量

Abstract

The results of observations of ground-strain and -tilt at Oura observatory since 1972, car-ried out by the super-invar bar extensometers of bow-string type and the tiltmeters of horizontalpendulum type, are firstly reported. Next, results of distance measurements of three base-linesin the Wakayama district, made with the geodimeters of model-6 and -600, are reported.In 1972, many noticeable shocks ranging in magnitude from 3.0 to 4.5 were occurred atthe lineament along the Hanayama-Oura line. The trends of strain accumuration obtainedfrom data of electro-optical distance measurements for the period from 1978 to 1985 were sig-nificantly different from those obtained for the period from 1969 to 1975. These strain changesmay be related to the seismic activity in this region.