The Jasmine Field is located in the Northern part of Pattani Basin, Gulf of Thailand. The objective of this study is to analyze and evaluate the possibility of fault sealing in the Jasmine A area by using well data and seismic interpretation from selected reservoir sand horizons, within a total interval thickness of approximately 1680 ft (512 m). These data were used for constructing depth structure maps, net-sand (isopach) maps, the model cross section of Allan diagram and Shale Gouge Ratio (SGR) calculation. In addition, these data were also used to investigate potential of fault sealing. From Allan diagram, the two analyzed faults in Jasmine A area have an effective capacity in sealing hydrocarbon and can be the entrapment of hydrocarbon accumulation in the area with different juxtaposed units. However, some sections have leakage potential where each horizon is juxtaposed against one another across the fault. As seen in the SGR calculation and the across-fault pressure difference estimation, the results confirm seal capacity and show the threshold for static hydrocarbon sealing. Furthermore, the methodology and the result in this research can be applied to predict the fault seal capacity in other areas of similar lithologies and structures and help to evaluate the potential in hydrocarbon accumulation.