variavel0=<b>Ana Paula de Araujo Costa</b> - paula@dep.fem.unicamp.br Universidade Estadual de Campinas-UNICAMP
<b>Denis José Schiozer</b> - denis@cepetro.unicamp.br Universidade Estadual de Campinas-UNICAMP
<b>Abstract.</b> The present work show some details of the Risk Analysis applied to the appraisal phase of petroleum field with emphasis in the analysis of the geological impact uncertaintes. This situation requires a detailed study using numerical flow simulation. However,the utilization of this tool can be increase the computacional time and invalidate the process.To make this process possible, some methodologies was developed to use some simplification in the Risk Analysis.The principal objective of this work is to quantify the impact of these simplifications, mainly, by the selection to the ideal number attributes. The procedure do define a simplifying criterion in a process is included in the quantification of the geological uncertainties through the description of the uncertainties attributes and its levels. The simplification procedure treatment in a Risk Analysis process is based on: (1) definition of the uncertainty attributes number, (2)sensibility study, (3) gradual combination influence analysis of the less critical attributes in sensibility study, (4)Aggregation attributes influence. The simulations results in these processes are combined to calculate the VPL (Liquid Present Value). After the statistical treatment of the results it is possible to define the Risk Curve.
<b>Keywords.</b> Uncertainty, Numerical Simulation, Risk Analysis, Appraisal phase.