NONLINEAR OSCILLATING STRUCTURES IN THE EARTHQUAKE AND SEAQUAKE DYNAMICS

The article deals with the problem of parametric excitation of oscilla ting structures during an earthquake and a seaquake associated with ex ternal forces. Tidal forces and their linear and nonlinear components are considered as possible causes of earthquakes. A seaquake is regard ed as a typical large-scale structural disturbance of the water surfac e resulting from the ocean bottom earthquake. There are given results of original laboratory seaquake modeling where wave structures with he xagonal and square cells appeared. The received wave lattices were sim ilar to Faraday ripples, but with the size of cells from 15 to 120 mm. These experiments provided parameters on transition from a wave struc ture to chaos. Comparison of laboratory experimental data with descrip tions of full-scale seaquakes and parametric wave theory has confirmed the submitted interpretation of the phenomenon. (C) 1996 American Ins titute of Physics.