XH地区K₁bs³上部发育的三角洲前缘薄砂岩储层是构造—岩性油气藏勘探的重要领域。近年来在该区应用常规波阻抗、叠前确定性反演都无法准确预测目的层薄砂岩储层的分布。应用JI-FI（阻抗与相联合反演技术），利用叠前地震道集数据，在不同岩相/流体相的纵波、横波速度和密度深度趋势约束下，将同时反演与贝叶斯分类相结合，采用最大期望算法，对阻抗和相进行迭代，实现了目标区岩相/流体相及岩石物理性质（纵波阻抗、横波阻抗、密度及纵横波速度比等）的定量预测。该方法克服了常规叠前反演依赖井建立低频模型，特别是在井少、薄互层地质条件下，井间波阻抗内插存在不确定性问题。储层预测结果与井吻合度高，为该区岩性勘探及井位部署提供了依据。

The thin sandstone reservoir in the delta front developed in the upper part of the K₁bs³ formation is an important area for the exploration of structural-lithological oil and gas reservoirs in the XH area. In recent years, Application of P-impedance and pre-stack deterministic inversion could not accurately predict the distribution of thin sandstone reservoirs in the target layer. In this paper, joint impedance and facies inversion（JI-FI） impedance and facies joint inversion technology is used. This technique uses pre-stack seismic gather data, and combines simultaneous inversion and Bayesian classification under the constraints of the P-wave, S-wave velocity and density depth trend of each lithofacies or fluid facies, the maximum expectation algorithm is used to iterate the impedance and facies, and the quantitative prediction of lithofacies/fluid facies and petrophysical properties （such as P-wave, shear wave impedance, density, V_p/V_s, etc.） in the target area is achieved. This method overcomes the uncertainty of inter-well P-impedance interpolation when conventional pre-stack inversion relies on wells to establish low-frequency models, especially under geological conditions with few wells and thin interbeds. The reservoir prediction results are in good agreement with the well, which provides a basis for lithological exploration and well location deployment in this area.