Research of “Focal Mechanism Analysis in subduction region of Java Sea by the case studies of Blitar Earthquake on May 17, 2011 has done by using the initial data of P waves recorded on seismograms. For the upward motion of the compression is denoted by (C), and the downward motion of dilatation is denoted by (D). This method is applied to find the orientation of earthquake fault of Blitar on May 17, 2011 with magnitude 6,1 SR. Epicenter located at 9.680 LS and 112.400 BT or 190 km southeast of Blitar,with depth 28 km. The results of data processing by using software focal mechanism is Nodal Plane 1, Strike 3350 Dip 330 Rake -1040 . Nodal Plane 2, Strike 1920 Dip 580 Rake -810. From the results of processing data founded that the orientation of the Blitar earthquake fault is “Normal Fault”. From the analysis of the “beach ball” earthquakes in the area and in according to the map of distribution of the earthquake was found that the earthquake fault of Blitar moving to the southeast of Blitar. Nodal plane 1 was selected by the reason of the geological and tectonic conditional which compatible with the movement plate type in that local area.
Key words: fault, focal mechanism solutions, strike, dip, rake,
Penulis : Windya Putri Dayas (H22107011)/Geofisika UNHAS