The effects of dynamic processes in the Earth's crust on the propagation of seismic waves have been observed in numerous investigations. Observables include changes of propagation velocities, anisotropy, scattering characteristics, and attenuation. Monitoring techniques use microseismicity, repeating earthquakes, repeated active sources or continuous ambient seismic noise. Potential processes that affect seismic wave propagation are stress changes and material destruction caused by large earthquakes, volcano and landslide dynamics, ground water changes, as well as production from hydrocarbon reservoirs and geothermal fields.
To contribute to the physical understanding of the relation between causative processes that alter local material characteristics and the seismic observables we invite papers on new observational field and laboratory investigations as well as studies that model these effects.
Additionally, temporal changes in properties of the seismic sources used, such as spatial distribution or frequency content, can affect the measured changes. Therefore, we also welcome contributions that focus on this aspect of the monitoring method, or on other methodological improvements.