Volcanic Tremor: Seismic Signals of (Almost) Unknown Origin

摘要: There exists strong evidence that the origin of volcanic tremor is caused by pressure fluctuations which are directly associated with degassing processes magma. The signals contain features also found in self-excited and self-sustained feed-back systems. Two-phase flow (liquid magma gas/steam) phenomena offer good possibilities at modeling sources agreement observations. However, observation alone does not allow us to draw specific conclusions on source mechanism. Different physical seismic two-phase concordance signal characteristics tremor. This implies severe restrictions application understanding dynamics activity. problem enhanced fact that, general, only a limited frequency band flow-induced observed (ca. 1-10Hz). extension of, mainly, lower cut-off values 0.01 Hz or less might strongly improve possibility establishing speculative models for than possible present.