抄録
Crustal deformation monitoring combined with seismic observations can be used in areas of high earthquake hazard in a joint interpretation for progress in earthquake research. Therefore, the 'Earthquake Research Institute' of Tokyo University runs the Nokogiriyama Observatory at the bay of Tokyo complementary to the seismological array. In April 1997 an Askania tiltmeter was deployed in a 10 m deep borehole in the observation gallery supplementary to the already installed water tube tiltmeters. It operated with only a small drift until June 1999. Recordings of the Askania and the water tube tiltmeters are compared with each other regarding signal/noise ratios, tidal residuals, ocean loading and meteorological effects to evaluate advantages and limitations of both instruments concerning future use in earthquake areas. First results of this comparison indicate generally good correspondence between the signals of the two instruments. Similarities and differences in the longterm drift, the tidal parameters and hydrologically and air pressure induced signals are discussed.
