<p>Oolitic beaches in the Triassic Feixianguan Formation are key gas reservoirs in the Northeastern Sichuan Basin. Accurately mapping their distribution is critical for reservoir characterization and exploration. Traditional workflow for mapping oolitic beach distribution mostly relies on manual interpretation of seismic attributes, which is labor-consuming and interpreter-dependent. Active contour model (ACM), which is widely applied in image segmentation, can be used to automatically characterize the distribution of oolitic beaches. We thus propose an automatic oolitic beach identification method based on the signed pressure force active contour model. To incorporate the characteristics of seismic attributes, we add another signed pressure force driven by the maximum change of inner region variance and name it hybrid signed force active contour model. The maximum change of inner region variance highlights the differences between oolitic beach and non-beach areas, thus enhancing the ACM stability and robustness for seismic attributes. We test our method using field data in the Northeastern Sichuan Basin. We first select the most sensitive seismic attribute, the maximum peak amplitude, using seismic forward modeling. Then, we perform our method as well as three state-of-the-art ACMs based on the seismic attribute. By comparing with the well data and seismic profile, the results show that our method outperforms traditional ACMs in terms of accuracy and reliability. Our findings reveal that oolitic beaches in the study area are predominantly distributed within the&#xa0;sea trough and decrease toward the platform margin, which is in accordance with the geological understanding.</p>