4 Petroleum resources of the us Qo: the total resource that is available over all time from the beginning of the oil industry to the exhaustion of the resource Economically Recoverable Discovered Produced /ll years Time Figure 2.3 History of cumulative discovery and production of finite resource consumed to depletion. For oil in the us, production has generally followed discovery by about 1 years4. Petroleum Resources of the US Q∞ : the total resource that is available over all time from the beginning of the oil industry to the exhaustion of the resource. Figure 2.3 History of cumulative discovery and production of finite resource consumed to depletion. For oil in the US, production has generally followed discovery by about 11years. Economically Recoverable