In recent years, significant breakthroughs have been made in the exploration and development of the X block in the Jingbian gas field. However, detailed reservoir characterization for this block remains insufficient, necessitating further research to enhance the development efficiency of the area. The main challenge lies in the thick loess layer covering the surface of the target block, which obstructs the use of seismic data for detailed reservoir characterization. To address this, a comprehensive study utilizing logging data, core sampling, and mercury injection tests has been conducted to investigate the sedimentary features, petrological characteristics, porosity traits, and physical properties of the Shihezi formation within the target block. Additionally, a three-dimensional geological model of the reservoir was constructed, enabling detailed reservoir characterization without seismic data. The findings reveal that the primary rock type in the Shihezi formation of the target block is quartz sandstone, predominantly developed in the distributary channel front subfacies of a braided river delta. The reservoir porosity is mainly characterized by dissolution pores, micropores, and micro-fractures, resulting in an overall low porosity and low to very low permeability gas reservoir with small and fine throats. By integrating previous geological understandings and applying well point constraints and facies controls, combined with sequential simulation methods, a more accurate lithofacies model and physical property model were established. This provides a solid foundation for reservoir numerical simulation and future development planning.