TY  - JOUR
A1  - Büyükakpınar, Pınar
A1  - Aktar, Mustafa
A1  - Petersen, Gesa Maria
A1  - Köseoğlu, Ayşegül
T1  - Orientations of broadband stations of the KOERI seismic network (Turkey) from two independent methods
BT  - P- and Rayleigh-wave polarization
JF  - Seismological research letters / Seismological Society of America
N2  - The correct orientation of seismic sensors is critical for studies such as full moment tensor inversion, receiver function analysis, and shear-wave splitting. Therefore, the orientation of horizontal components needs to be checked and verified systematically. This study relies on two different waveform-based approaches, to assess the sensor orientations of the broadband network of the Kandilli Observatory and Earthquake Research Institute (KOERI). The network is an important backbone for seismological research in the Eastern Mediterranean Region and provides a comprehensive seismic data set for the North Anatolian fault. In recent years, this region became a worldwide field laboratory for continental transform faults. A systematic survey of the sensor orientations of the entire network, as presented here, facilitates related seismic studies. We apply two independent orientation tests, based on the polarization of P waves and Rayleigh waves to 123 broadband seismic stations, covering a period of 15 yr (2004-2018). For 114 stations, we obtain stable results with both methods. Approximately, 80% of the results agree with each other within 10 degrees. Both methods indicate that about 40% of the stations are misoriented by more than 10 degrees. Among these, 20 stations are misoriented by more than 20 degrees. We observe temporal changes of sensor orientation that coincide with maintenance work or instrument replacement. We provide time-dependent sensor misorientation correction values for the KOERI network in the supplemental material.
Y1  - 2021
U6  - https://doi.org/10.1785/0220200362
SN  - 0895-0695
SN  - 1938-2057
VL  - 92
IS  - 3
SP  - 1512
EP  - 1521
PB  - Seismological Society of America
CY  - Boulder, Colo.
ER  -