Recent observations in the USSR appear to suggest that wide‐band electromagnetic radiation occurs just prior to earthquakes. To apply this phenomenon to earthquake prediction, measurements have been carried out at the Sugadaira Space Radiowave Observatory in Japan under the USSR‐Japan Cooperation Program in 1980. The recorded noise level at 81 kHz is comparatively quiet throughout the day and night. However, about one‐half hour before the main shock of a magnitude 7 earthquake at 0733 UT on March 31, 1980, the instrument recorded an anomalous amplitude increase to 15 dB higher than the normal level. VLF data recorded synoptically at Sugadaira suggest that unusual impulsive radiation at frequencies below 1.5 kHz also occurred shortly before the earthquake. Similar 81‐kHz emissions were observed prior to magnitude 5 and 6 earthquakes on September 25, 1980, and January 28, 1981.

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The alternative view of the current status and perspective of seismic prediction studies is discussed. In the problem of ascertainment of the uncertainty relation Cognoscibility-Unpredictability of Earthquakes, priorities of works on short-term earthquake prediction are defined due to the advantage that the final stage of nucleation of earthquake is characterized by a substantial activation of the process while its strain rate increases by the orders of magnitude and considerably increased signal-to-noise ratio. Based on the creep phenomenon under stress relaxation conditions, a model is proposed to explain different images of precursors of impending tectonic earthquakes. The onset of tertiary creep appears to correspond to the onset of instability and inevitably fails unless it is unloaded. At this stage, the process acquires the self-regulating character and to the greatest extent the property of irreversibility, one of the important components of prediction reliability. Data in situ suggest a principal possibility to diagnose the process of preparation by ground measurements of strain-rate-dependent parameters, like electromagnetic emission, etc. Laboratory tests of the measurements of acoustic and electromagnetic emission in the rocks under constant strain in the condition of self-relaxed stress until the moment of fracture are discussed in context. It was obtained that electromagnetic emission precedes but does not accompany the phase of macrocrack development.

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