Normal" style="margin: 0cm 0cm 0pt;">///Long-offset
    NMO correction of shallow layers in vertical transversely isotropic media(VTI)
    is always one of the difficulties in seismic data processing. After
    conventional NMO correction, the seismic events are strongly stretched.
    Moreover, common signal interlacing even causes the distortion of seismic
    events and the signals within the accuracy range cannot be corrected even by
    applying high-precision non-hyperbolic traveltime formula. Therefore, shifted
    first-arrival traveltime NMO velocity and η inversion for VTI media was proposed.
    Firstly,  based on the traveltime of
    first-arrival points, the authors carry out whole shifting of signals to remove
    NMO stretching. Then, shifted first-arrival traveltime NMO velocity and η
    inversion for VTI media was used to improve the traditional similarity
    coefficient formula. Three-layer VTI model testing result indicates that
    shifted first-arrival traveltime NMO can correct long-offset events without
    stretching, and velocity and η inversion at first-arrival points can largely
    improve the accuracy of inversion.