Fitting, Filling, and Filtering of Salt Dilution Breakthrough Curves for Reduced Field Time, Increased Accuracy, and Optimized Happiness

The Salt Dilution Tracer method has been used in some form for >100 years (Allen and Taylor, 1923, Østrem, G. 1964, Moore, D 2004).  Recently, the method has undergone a renaissance as techniques and equipment have been improved, facilitating lower dosing (<100g/cms) and increased accuracy.  This paper studies the impact and best practices for filtering, extrapolation, and interpolation of the breakthrough curve to reduce uncertainty, and more importantly, extend the tail of the slug injection signal if the measurement is ended early.  By extrapolating, the user can leave the field in as little half the time, while introducing only +/- 5% uncertainty.  We examine different fitting models (gamma, SCS Unit Hydrograph, χ², etc) and fitting methods.  An online fit/fill/filter tool is presented and happiness of user is optimized.