SH‑waveform modeling of small local seismic events in Ladoga lake

摘要

A lot of seismic phenomena with small magnitude has been taking place in the Ladoga lake region (northwestern Russia).One of them is the earthquake which was recorded on the 31st of July, 2010 followed by the swarm of microearthquakesnear Nikonovsky cape. There is only one station in the region that is why it is difficult to process the data. In this work, wepropose a new approach to construct synthetic seismograms of the main event with minimum data. Also this approachapplies us to calculate parameters of the source. The approximate magnitude of the main event is M_L = −0.8 . For swarmevents, we have magnitude values from −1.0 to −2.6 . The data of swarm events (microearthquakes) is used to test thetechnique of constructing synthetic seismograms. The approach we propose is based on Green’s function method withusing two temporal -sequences (the Lorentzian function and the continuous Dirichlet kernel). A comparison of syntheticand real seismograms shows that the Lorentzian function is better to describe small local events, and the continuousDirichlet kernel is more appropriate for earthquakes. This approach can be generalized to various problems of differentnature.