Estimated ultimate recovery prediction using oil and gas production decline curve analysis and cash flow analysis for resource play

Abstract

Petroleum production forecasting is important for well performance evaluations, which are routinely conducted using decline curve analysis (DCA). DCA relies on the use of empirical curve fitting or the Arps decline model. However, the application of DCA in resource plays poses the problem of reserve overestimation, and by the lack of wells with enough production history to validate models. Despite the recently presented methods in DCA, it is difficult to estimate the exact amount of resources. In this study, we propose a workflow for overall production data analysis to predict estimated ultimate recovery (EUR) for resource plays. We derive a representative probabilistic type curve for considering uncertainty using production data. We employ a modified hyperbolic decline coupled with an exponential decline trend using a standard terminal decline. We use the decline envelope forecast in a probabilistic production decline band by integrating multiple well data. In addition, a cash flow analysis is conducted to determine the production period. A sensitivity analysis for identifying the economic factors affecting the evaluation of oil and gas producing fields is also performed. The EUR for the study area was calculated as 25.68 Mbbl of oil and 107.84 MMcf of gas, and the cash flows were adequate to support production behavior for a period of 14 years.