Abstract: Fault sealing evaluation is a critical component in the exploration of complex structural reservoirs, where quantitative methods based on 3D seismic data represent a key research focus for reservoir assessment and deployment in data-sparse areas or early exploration stages. Building upon geological evaluation principles, this study innovatively proposes an integrated seismic-geological approach by incorporating 3D seismic data. Research findings indicate that lithologic configuration of fault walls, shale smear thickness (Shale Gouge Ratio, SGR), and fault dip angle are the primary controls on sealing capacity. Through 3D seismic volume analysis and forward modeling, we reveal significant seismic attribute discrepancies (e.g., amplitude variation rate, frequency anomalies) across the fault planes of sealing structures. By establishing quantitative relationships among seismic attribute discrepancy indices, SGR, fault dip angles, and discovered hydrocarbon accumulations, we developed a quantitative characterization method for fault sealing capacity based on seismic attribute variations. This method enables effective evaluation of fault sealing in data-sparse regions. Its application in the Dongying Sag of the Jiyang Depression succeSGRully identified 12 sealing faults, guided the deployment of 8 exploration wells, and achieved an 85% drilling success rate in encountering oil layers, providing robust support for target optimization during early-stage exploration.