摘要
The source mechanism of underground nuclear explosions is remarkably different from that of earthquakes in both spatial radiation pattern and source time-function (STF). Small underground nuclear explosions can be used as empirical Green’s functions (EGF) to isolate the source-time spectrum of a large suspected earthquake occurred in a Nuclear Test Site (target area) by the spectral division method. As this study shows, with high-quality data, the quotient spectrum can be transformed to the time domain, yielding the apparent far-field source-time function of the large suspected event. The relative source time-function (RSTF) of a nuclear ex-plosion is usually a simple pulse with a duration of about 1 s., while an earthquake’s is more complicated with a series of pulses and a longer duration. The RSTF can be used as a nice dis-criminant to distinguish the nature earthquakes from underground nuclear explosions in target areas.
The source mechanism of underground nuclear explosions is remarkably different from that of earthquakes in both spatial radiation pattern and source time-function (STF). Small underground nuclear explosions can be used as empirical Green’s functions (EGF) to isolate the source-time spectrum of a large suspected earthquake occurred in a Nuclear Test Site (target area) by the spectral division method. As this study shows, with high-quality data, the quotient spectrum can be transformed to the time domain, yielding the apparent far-field source-time function of the large suspected event. The relative source time-function (RSTF) of a nuclear ex-plosion is usually a simple pulse with a duration of about 1 s., while an earthquake’s is more complicated with a series of pulses and a longer duration. The RSTF can be used as a nice dis-criminant to distinguish the nature earthquakes from underground nuclear explosions in target areas.
基金
This work was partially supported by the National Nature Science Foundation of China(Grant No.40134010).