Tiltmeter Observations at the 'Apatity' Seismic Station in 1959-1960

摘要

On the basis of the inclination data obtained at the Apatiti seismic station by an azimuth installation that consists of a number of the H - VI type inclination meters there have been observed some periodic variations of the earth surface inclinations and a linear component apriorily related in its main part to the 'secular' course. The daily inclination course is generally small and does not exceed 0.04 sec of arc. In some cases semi-diurnal inclinations not exceeding 0.002 sec. of arc may be distinguished against the background of the daily course. The annual inclination course of 1960 along the N--S component is 2.6 sec. of arc and along the W--E is 0.7 sec. of arc. Against the background of the annual course there may be strictly distinguished a wave of inclinations with a period of 4.0--4.5 months and an amplitude of about 1.3 sec. of arc along the N--S and nearly 0.35 sec of arc along the W--E. In the upheaval azimuth of 339 degrees, which is directed towards the uplift of the earth's crust, the 'secular' inclination course of 1960 comprises 6.56 sec of arc. (Author)