Risk, Uncertainty and Priorities — Quantitative Models

Quantitative basin analysis has three major components: (i) determination of the spatial and temporal dynamic evolution of the sediments in relation to evolving basinal structure, and with respect to the spatial variations of lithologic and diagenetic fabrics; (ii) determination of the thermal history of sedimentary units in relation to their burial histories; (iii) determination of the hydrocarbon generation, migration and accumulation histories of all hydrocarbons generated in the basin, so that the relative timing of hydrocarbon evolution can be assessed in relation to the development of traps and their seals, and in relation to the continued integrity of sealed traps after hydrocarbon emplacement. In this way a better appreciation can be obtained of potential hydrocarbon sites in a basin. On the path to achieving such an evaluation of hydrocarbon site determination, four major concerns have to be addressed in relation to the output from any basin analysis model. The concerns are: (i) resolution; (ii) sensitivity; (iii) uniqueness; (iv) precision. These four factors are controlled to a greater or lesser extent by three overriding inputs: (i) intrinsic assumptions; (ii) parameter values; (iii) quality, quantity and sample spacing of data.