ESTIMATING SEISMOMETER ORIENTATIONS FROM TELESEISMIC P-WAVE PARTICLE MOTION ANALYSIS

Abstract

Three-component seismometers are essential for seismological methods that demand rotational transformations on the horizontal components. In order to verify the orientation of seismometers installed on Pantanal, Chaco and Paraná Structural Studies Network (XC-USP) and on Seismological Observatory Network (OS-UnB), we used P-wave Particle Motion Analysis combined with Directional Statistics. We also tested this method in a well-known misoriented station (IU.RCBR), which belongs to the Global Seismograph Network (IU-GSN). In addition to station IU.RCBR, with orientation error of +55.80º, we detected 3 stations with errors larger than ±10º: OS.FUN1 (-10.14º), OS.SIM2 (-11.93º) and OS.SSV2 (-27.16º). The orientation error of the last one was possibly caused by the non-declination of the compass used to align the sensor with respect to the geographic north.