Development of a Ground Truth Database for Improvement of CTBT Monitoring in the Eastern Mediterranean Region

摘要

A reliable Ground Truth (GT) database is crucial to improve the monitoring of small seismic events in the Middle East. Therefore, the Geophysical Institute of Israel (GII), Bogazici University, Kandilli Observatory and Earthquake Research Institute, Istanbul (Turkey) (KOERI), TUBITAK Marmara Research Center, Earth and Marine Sciences Research Institute, (Turkey) (EMSRI) and the Geological Survey Department of Cyprus (GSDC) joined their efforts to develop a database using seismic data from the national networks and arrays advantageously placed in the eastern Mediterranean region. The elaborated GT database includes: 1) GT2-GT5 data for earthquakes and aftershocks that are well constrained by dense local and portable networks; 2) GT2 data of large routine quarry blasts supplied by blast pattern parameters; and 3) GT0 data for controlled routine quarry blasts and special design calibration explosions conducted previously and during project duration, including detailed blast pattern design. At the first stage of the project, we elaborated the database for calibration of the International Monitoring System (IMS) stations EIL and MRNI relative to local GT events, well located by the Israel Seismic Network (ISN) stations. We collected 27 GT0 events (including the three Dead Sea calibration explosions in November 1999) and 23 GT2 industrial explosions from quarries in the Negev and Galilee (local magnitude ML = 2.7-3.1); all the explosions are recorded with a high signal-to-noise ratio (SNR) up to 250 km. About 20 accurately located (GT2-GT5 rank) earthquakes in Israel (ML is greater than 3) were selected.