Perpustakaan Digital ITB

This study tries to assess the patterns and characteristics of geophysical effects from GPS observation data from January 1st 2011 until December 31st 2011 derived by Indonesian GPS Permanent Stations Network (IPGSN) that run by Geospatial Information Agency (Badan Informasi Geospasial [BIG]), hence to investigate the applicability of global geophysical effects models in Indonesia. The geophysical effects model issued by McCarthy has been recommended the IERS Convention 2003 (McCarthy, 2004). The variables of geophysical effects that will be investigated consist of total of 3 (three) phenomena, namely the Solid Earth Tides (SET), Ocean Tide Loading (OTL) and Atmospheric Pressure Loading (APL) data. The GPS observation data consists of 10 stations which distributed in 2 sites in Sumatera, 3 sites in Java, 2 sites in Kalimantan, 2 sites in Sulawesi and 1 site in Papua, the interval data is 30 seconds which are processed using Kinematic Precise Point Positioning (KPPP) method using RTKLib software and relative method using GAMIT/GLOBK software in long baseline and short baseline so that resulting in time series of total geophysical effects, which is then analyzed using spectral analysis to know the spatial pattern and characteristic at each station. The result show the patterns and characteristics of geophysical effects for each site that are dominated by semi-diurnal phenomenon at vertical (UD) and East-West (EW) component, on the other hand, North-South (NS) component are dominated by diurnal phenomenon. Geophysical effects displacement is two to three times more influenced in vertical component than in horizontal component. The biggest displacement in vertical component of geophysical effects is in CCLP station, and the smallest displacement is in CBAL station. In NS component the biggest displacement is in CBIT station and the smallest displacement is in CPKL station. In EW component the biggest displacement is in CPKL station and the smallest displacement is in CBAL station. In the horizontal component, the spatial pattern create semi-annual and annual pattern, which has a different value each station. Different patterns indicate a difference in rheology at each station. The patterns and characteristics of geophysical effects both on horizontal and vertical components in each station are different. Geophysical effects model applicable to Indonesia regions for practical application with standard deviation higher than 0.05 meters. From relative data processing method, the geophysical effects models are needed for the processing of long baseline. While short baseline geophysical effects models are not very influential.