Abstract: A method of improving operation of a petroleum reservoir using geotechnical and economic analysis includes classifying a petroleum reservoir using reserves ranking analytics (RRA) and then making one or modifications to the operation of the reservoir. RRA classification includes establishing reservoir classification metrics for each of the following categories: 1) resource size; 2) recovery potential; and 3) profitability. The reservoir can be classified based on at least one metric in the profitability classification category, and also based on at least one metric in one or more of the resource size classification category or the recovery potential classification category. Classification of reservoirs according to RRA can aid in reservoir management, planning, and development.