Brian Savage and Don V. Helmberger
Kursk explosion
Bulletin of the Seismological Society of America (August 2001), 91(4):753-759

Abstract:
On 12 August 2000 two explosions damaged the Russian submarine, the Kursk. The largest event was well recorded at seismic networks in northern Europe, which we then modeled. We developed a hybrid method based on generalized ray theory that treats an explosive source embedded in a fluid and recorded along continental paths. Matching record sections of observations with synthetics, we obtain an estimate of explosive size of slightly over 4 t. Several earth models determined previously, K8 and a Baltic model, were used to assess accuracy. These results are in general agreement with other investigators using more empirical methods. Knowing the conventional missile yield and the explosion size allows for an estimate of approximately five missiles exploded in the second larger explosion onboard the Kursk.