Abstract: Rankin Platform is an important gas-condensate prolific zone in the North Carnarvon Basin. The platform has been uplifted in the Early Jurassic, and became a depo-center again in the Cretaceous. The thick Middle and Upper Triassic Mungaroo Formation is an important exploration target in the platform. Although gas accumulations in the platform have been sourced from multiple formations, the Middle and Upper Triassic Mungaroo Formation is the important proved source rock for gas. This source rock generates gas for quite a few reservoir-source rock combinations. Barrow-Dampier sub-basin is the terminal area for hydrocarbon migration. Because the Barrow and Dampier areas receive slightly different hydrocarbons, and the gas discoveries in the north of the platform have more condensate content than those in the south. Well developed structural traps, good seal and multiple source rocks may account for the concentration of gas accumulation in the platform

Key words: petroleum geology, Goodwyn condensate gas field, Gorgon condensate gas field, cause of gas accumulation, Rankin Platform