1. Seismic Tomography
Inversion of longperiod seismic waveforms allows to derive threedimensional models of shear wave velocities of the lithosphere and upper mantle. Calculation of anisotropic models, automatized handling of large datasets, relation between deformation of the lithosphere and anisotropy are current topics of methodical research. Besides the waveforms themselves, certain parameters of the waveforms, such as traveltimes, polarisation of body waves, group- and phasevelocities of surface waves can be measured and applied in an inversion. Of particular interest is the study of the Earth's upper mantle beneath Europe, the Mediterranean and in Northern Europe around the Trans-European Suture Zone.
2. Ultrasonic studies
Analysis of seismic waves in the ultrasonic frequency band utilizes commonly the traveltimes of first arriving body waves. Using the entire waveform poses intriguing challenges. Using surface waves, one can study the upper few centimeters of a sample (e.g. rock, concrete) and determine variations in the elastic moduli which are indicative of, for example, weathering.
3. Seismicity studies
Characterizing the current state of active faults is an important topic of geophysical studies. Locating seismic events, analysis of their spatio-temporal clustering and studies of seismic coupling on the fault interface shed insight on the physical properties of active faults. Our particular focus is on studies of seismicity in the Aegean, one of the seismically most active regions in Europe.