Production time-series analysis has three reservoir-characterization objectives: determine the initial reservoir drive mechanism, understand the effects of previous reservoir production strategies, and, most importantly, understand how the reservoir architecture has influenced fluid flow. The combined influence of these three factors is what has created the reservoir’s production history. Knowledge of their relative effects is critical in reservoir characterization and in determining reserve-growth potential. To achieve the objectives of production time-series analysis, five main tasks must be accomplished, preferably in the order listed below:

1. Analyze initial and spatial time variation of fluid chemistry.
2. Analyze initial conditions for fluid contacts from completion, workover, logs, and pressure.
3. Graph production and annotate along with production-strategy history.
4. Map and analyze time-series history of fluid production.
5. Determine flow direction of injected and encroaching fluids.

In this module, we will examine tasks 3, 4, and 5; graphing production and annotating production-strategy history, mapping and analyzing time-series fluid production history, and determining flow direction of injected and encroaching fluids. Module 12 covers the first two tasks to be accomplished when performing production time-series analysis of a reservoir.