Opak fault that are located along the Opak River flow is part of the earth's plates are kept active, which causes all things that are moving and shifting on participate, not least Titik Dasar Teknik (TDT), which is the National Mapping Framework.
The shift that occurred in TDT will also affect the maintenance of land registration data. Therefore, this study aimed to determine; 1) The value of the shift to the west and east of the Opak Fault; 2) The pattern shifts that occurred on 3rd class TDT around Opak Fault; 3) The impact of the shift to activity measurement and cadastral mapping and how the solution.
The method used is a comparative study with a quantitative approach. This study compares the coordinates of 3rd class TDT observations in research tied to two Base Station is CORS BPN Bantul and InaCORS BIG Bantul with coordinates on secondary data Monument Books (DGN-95). To get the parameters as well as the shifting patterns allies point coordinate transformation (TDT) of DGN-95 to ITRF 2008 (CORS) and ITRF 2012 (InaCORS) with Helmert and Affine transformation method. Transformation parameters used are determined by calculating the value of the smallest variant posteriori. The impact on activity measurement and cadastral mapping is determined by reference to the provisions on Juknis PMNA / KaBPN 3, 1997.
Based on the results of research and analysis, it is known 1) The average value of the shift towards 3rd class TDT in the area around the Opak Fault amounted to 0.875 m, the average azimuth 32o31'32,36 "and directed the North-East; 2) Transformation of coordinates used in the area around the Opak Fault is a Helmert transformation with a scale factor parameter value (?) of 0.99999533 and factor rotation (?) of 2.93" and a translation factor of a = -6.936260223 and b = 7.760559082 to use binding at CORS BPN Bantul. Parameter scale factor (?) equal to 0.999995859 and factor rotation (?) by 2.98 "and the translation factor of
a = -7.205501556 and b = 7.448883057 to use binding on InaCORS BIG Bantul; 3) Based on Juknis PMNA / KaBPN 3, 1997 which provides tolerance to a shift by 0.100 m (settlement) and 0.250 m (agriculture), then the shift does not meet tolerances. To take advantage of the coordinates 3rd class TDT necessary coordinate transformation using transformation parameters generated in this
research.
The results of this research can contribute significantly to the Ministry of Agricultural and Spatial Planning / National Land Agency in the form of information about the magnitude and pattern shift that occurred in the Framework of the National Mapping especially 3rd class TDT around Opak Fault and value transformation parameters are used for the measurement and cadastral mapping .
Keywords : Shift , Opak Fault, 3rd class TDT , CORS , InaCORS