부산대학교 도서관

Uncertainties in the estimates of hydrocarbon volumes are traditionally given by the Monte Carlo method, which is based on classical probability theory. A new and better way to achieve the same objective is to use fuzzy arithmetic. This new math is based on possibility theory derived from fuzzy set theory. A comparison of these two approaches is given, using an example from a recent AAPG Bulletin paper. The fuzzy mathematics approach is more advantageous because, unlike the Monte Carlo method, it does not have to assume the (statistical) distributions of geologic variables, and also because of its parsimonious computations. Furthermore, this new approach has revealed that the estimates of the volumes of petroleum available for entrapment are unreliable where the ratio of the volume expelled from source rock over the volume lost during migration is near unity.