The fifth member of Xujiahe Formation（Xu-5 member）in Ziyang-Dongfengchang Block of central Sichuan is characterized by low porosity

low permeability

and strong heterogeneity. This study aims to develop a reliable logging interpretation model and to establish the lower limits of effective reservoirs using well logging

core

and gas testing data. The research focuses on the correlation among four key properties: lithology

physical properties

electrical properties

and gas content following core homing and log normalization. A significant correlation exists between the lithology

physical properties

electrical properties

and gas content. Gamma ray readings increase as particle size decreases

aiding in sediment characterization. Resistivity curves effectively identify calcium-bearing sandstones. A strong positive correlation exists between sonic differential time and porosity. Gas content is positively correlated with physical properties

indicating richer gas zones correlate with specific log signatures. Based on these relationships

a comprehensive interpretation model for porosity

permeability

and water saturation was established

alongside criteria for reservoir identification. The application of these findings in production scenarios demonstrates consistency between reservoir logging

gas testing

and experimental results with the established four-properties relationship diagram. The calculated physical property parameters from the logging interpretation model align well with core test outcomes

and gas production profile testing corroborates the reservoir identification criteria. This study provides critical technical support for designing testing schemes and optimizing resource extraction.