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Low-field nuclear magnetic resonance (NMR) has been widely applied in the oil industry as a noninvasive technique for rock analysis. There are many organic compounds, such as kerogen, in unconventional shale resources. However, it is difficult to evaluate solid organic matter in shales using common NMR techniques. Previous work has shown the use of a solid echo on shale samples provides more information than the standard T 1–T 2 method with spin echo. But for multiple homonuclear dipolar coupling present in shales, solid echo is less efficient. We propose a new multimagic-echo sequence for T 1 and T 1–T 2 measurements. The magic echo and standard T 1 and T 2 measurement technologies are combined to provide a more complete evaluation of hydrogen-containing shale sample components. Compared with other measurements, magic-echo measurements provide more signal of organic matters in shale samples. The additional signal is contributed by homonuclear dipolar coupling in organic matter. The partial least-squares regression (PLSR) method is used to analyze the relationships between organic geochemical properties and T 1–T 2 correlation data. The results presented here show that the T 1–T 2 peak distributions provided by magic-echo NMR agree well with the organic geochemical properties of shales. This method should make the NMR measurement of shales for the detection of organic matter a common technique.

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