A New Statistical Method for Interpreting Production Logs

Production logging suites often consist of some redundant measurements. For example, water holdup in wells producing oil and water is commonly measured by both fluid density and fluid capacitance logs. Each of these logs will contain some error, the level of which is likely different for each log. We present a statistical method for combining multiple log measurements so that the overall error in the interpreted parameter is minimized. The method is applied to multiple holdup logs and to interpreting multiple passes of a spinner flowmeter. The new technique yields the statistically most accurate interpretation and also provides an estimate of the statistical error involved. Synthetic logs are used to prove that the method minimizes the error in the interpreted flow profiles. Field examples of multiphase log suites and multipass spinner flowmeter logs illustrate the applications of the new method.

A New Statistical Method for Interpreting Production Logs Conference Paper