Constraining crustal and uppermost mantle structure beneath station TBZ (Trabzon, Turkey) by receiver function and dispersion analyses

CAKIR O., Erduran M.

GEOPHYSICAL JOURNAL INTERNATIONAL, vol.158, no.3, pp.955-971, 2004 (SCI-Expanded) identifier identifier


We jointly invert teleseismic radial-component receiver functions and regional Rayleigh and Love surface-wave group velocities for 1-D shear-wave velocity structure beneath station TBZ located on the northern side of the eastern Pontides. An influence factor is employed to control the relative influence of receiver function and surface-wave dispersion on the resultant velocity-depth profile. Radial- and transverse-component receiver functions at station TBZ exhibit an azimuthal amplitude and polarity pattern consistent with 2-D receiver structure that has a general dip direction towards approximately south. The radial-component receiver functions are least affected by the dipping structures along the strike direction and thereby we prefer teleseismic events sampling along-strike structures to alleviate the deflecting effect of dipping interfaces on the 1-D solution. The 1-D inversion effectively reveals the two-layer nature of the crust which is perturbed by high- and low-velocity layers, and serves as a provisional model for the 2-D forward modelling. Minor-to-moderate changes to the 1-D model, such as changing depth to and velocity contrast across an interface, are needed to achieve the results with the 2-D modelling. Dipping interfaces and seismic anisotropy are included in the 2-D modelling to fit both radial- and transverse-component receiver functions.