TY  - JOUR
A1  - Hannemann, Katrin
A1  - Papazachos, Costas
A1  - Ohrnberger, Matthias
A1  - Savvaidis, Alexandros
A1  - Anthymidis, Marios
A1  - Lontsi, Agostiny Marrios
T1  - Three-dimensional shallow structure from high-frequency ambient noise tomography: New results for the Mygdonia basin-Euroseistest area, northern Greece
JF  - Journal of geophysical research : Solid earth
N2  - We examine the use of ambient noise cross-correlation tomography for shallow site characterization using a modified two-step approach. Initially, we extract Rayleigh wave traveltimes from correlation traces of vertical component seismic recordings from a local network installed in Mygdonia basin, northern Greece. The obtained Rayleigh wave traveltimes show significant spatial variability, as well as distance and frequency dependence due to the 3-D structure of the area, dispersion, and anelastic attenuation effects. The traveltime data sets are inverted through a surface wave tomography approach to determine group velocity maps for each frequency. The proposed tomographic inversion involves the use of approximate Fresnel volumes and interfrequency smoothing constraints to stabilize the results. In the last step, we determine a final 3-D velocity model using a node-based Monte Carlo 1-D dispersion curve inversion. The reliability of the final 3-D velocity model is examined by spatial and depth resolution analysis, as well as by inversion for different model parameterizations. The obtained results are in very good agreement with previous findings from seismic and other geophysical methods. The new 3-D VS model provides additional structural constraints for the shallow sediments and bedrock structure of the northern Mygdonia basin up to the depth of similar to 200-250 m. Present work results suggest that the migration of ambient tomography techniques from large scales (tens or hundreds of km) to local scales (few hundred meters) is possible but cannot be used as a black box technique for 3-D modeling and detailed geotechnical site characterization.
Y1  - 2014
U6  - https://doi.org/10.1002/2013JB010914
SN  - 2169-9313
SN  - 2169-9356
VL  - 119
IS  - 6
SP  - 4979
EP  - 4999
PB  - American Geophysical Union
CY  - Washington
ER  -