Abstract: To accurately characterize the highly heterogeneous, thin-bedded effective reservoirs in fan-delta deposits of Nantun Formation, in Wunan Sub-sag, Hailar Basin, this study evaluates the applicability of seismic waveform indication inversion. Based on lithology sensitivity analysis, gamma-ray (GR) logs are selected to distinguish sandstone from mudstone. Cross-plots of resistivity (>3.5 Ω·m) and density (<2.45 g/cm³) are used to screen sensitive parameters for identifying effective reservoirs. After comparing various inversion methods, waveform indication inversion was adopted with four sample sets corresponding to sedimentary microfacies. GR inversion was first conducted for lithology identification, followed by cross-plot inversion of resistivity and density data to quantitatively predict effective reservoirs. The inverted sections clearly reveal "mudstone-over-sandstone" cycles and 2 m-scale mudstone interlayers. Resistivity-density cross-plot sections are highly consistent with interpreted results from well log. Validation using 29 blind wells yields an average coincidence rate of 87.57%. Combined with structural and accumulation conditions, six favorable blocks (total area 6.09 km²) were selected, with predicted reserves of 673.554×10⁴ t, and a six-well deployment plan was proposed. Waveform indication inversion significantly improves prediction accuracy for thin, heterogeneous fan-delta effective reservoirs, providing a reliable technical basis for reservoir evaluation and development in similar continental basins.