Simulation of Triggered Earthquakes in the Laboratory

The experiments were conducted for the study of stick-slip at the contact between two granite blocks. Three cases were studied under the following conditions: 1) the increase of load at a constant rate; 2) the additional application of sinusoidal oscillations in the frequency range from 1 to 30 Hz; 3) subjection to the impulse in the kilohertz frequency range. The imposition of sinusoidal oscillations with the amplitude of 15% of the maximal load caused the reduction of time by 10% for the next stick-slip occurrence, as compared to that expected during the gradual loading. This effect is discussed in terms of durability. The high frequency impulse influence increased this effect and also caused essential changes in the amplitude of elastic oscillations generating during the slick-slip The trigger phenomena should be integrated m prediction models of the time and magnitude of earthquakes.