A new seismic technology is presented based on the identification of endogenous events from microseisms. The energy of these events is 10~(-9) of that of earthquakes observed at standard seismic stations, i.e., seismic events with magnitudes M up to ～ -4 or -5. Based on the analysis of statistics for such nanoseismic manifestations recorded in the course of field works in the Arkhangelsk region, we demonstrated the possibility of distinguishing low-active fractures on platform territories. Three-component short-period observations (up to 3 h) are needed to obtain the results. They allow us to estimate quantitative characteristics of seismoactive medium in the neighborhood of 1-3 km around the point of recording. Mapping of the activity of the territory is based on the calculation of the coherence function for the records, whose statistical analysis allows us to obtain an analog of the earthquake recurrence plot for the range of microseismic and nanoseismic events. In addition to the methodological aspect, we have experimentally demonstrated for the first time the presence of endogenous nanoseismic manifestations (nanoearthquakes), which had previously been predicted only theoretically.
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