Seismic identification of lithofacies of Cenozoic stratigraphic in the Yongding River Basin

In order to support the multi-factors basic geological survey in the important economic zone of the Yongding River Basin in the new period, we developed high-resolution seismic detection test.Under the guidance of seismic stratigraphy and seismic sedimentology, we used some key techniques such as well-seismic calibrat, wave impedance inversion and 90° phase method to compare the characteristics of core, well logging and seismic wave field.The Cenozoic in the survey area has been identified and analyzed in terms of fine geological structure, stratum and lithofacies.The research results show that the wave impedance inversion and 90° phase transformation have good effect on logging and lithology calibration, the sediments in different facies zones have obvious characteristics on the wave impedance section, and the wave impedance value has a good relationship with the lithology grain size, the superimposition and combination of river course, water-logged depression and delta are described in detail.The wave crest of 90° phase section is consistent with the mid-high impedance, it can identify the distribution of channel sand body simply and quickly.