Abstract
NMR logging techniques have proven to be useful tools for a variety of formation rock properties and fluid typing applications. In the last decade, numerous improvements have been made both to multi-frequency NMR logging instruments and to data acquisition methods that have significantly enhanced the data quality and expanded the NMR logging applications envelop. On the other hand, these more versatile acquisition methods collect a large quantity of data that may seem overwhelming to most non-expert NMR users. To overcome the complexity of NMR logging and facilitate the wellsite decision-making, we have developed a number of simple, robust NMR log-based indicators for identifying hydrocarbon gas or oil, for detecting borehole rugosity contamination, and for recognizing vugs in carbonate reservoirs.