Real Time Petrophysical Data Analysis for Well Completions Installed in Oil Fields in the Amazon Basin in Ecuador

Abstract

Petrophysical interpretation of Logging While Drilling (LWD) data, acquired real time or later downloaded from memory data, is applied to estimate valuable reservoir rock and fluid properties. Permeability is derived from porosity while fluid saturations from resistivity logs. Petrophysical interpretation output depends on log data quality control, local area georeservoir-knowledge and understanding of tool physical principles. This is of paramount importance when core data is not available, and then core calibration is absent. Petrophysical data interpretation results are the most valuable input for updating any base case completion scenarios, for last calibration and refinement of the completion hardware design, prior to its installation in the ground. It is recommended to include several sensitivities and scenarios to assess well completion performance dynamic ranges in terms of fluid rates, water cut and available drawdown pressures. Preparation of cross-plots, standard deviation flags and petrophysical attributes are all integrated to minimize risk and uncertainties related to both reservoir rock and fluid properties. Both LWD data quality control and petrophysical interpretations are often performed parallel and or simultaneously to ongoing drilling operations. Often, time is short between the drill bit reaches TD to the installation of the completion hardware. This paper presents the methodology, workflow and only a couple of field examples of successful petrophysical-completion synergism in recent well completions installed with ICDs and AICDs in oil producer wells in Ecuador Amazon Basin.