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There are many hydrogen-bearing components in shale, including kerogen, free oil, adsorbed oil, free water, adsorbed water, and structural water. Measuring the content and distribution of each component is important to understand the occurrence mechanism of shale oil. The nuclear magnetic resonance (NMR) T 1 −T 2 map can be used as a non-destructive technique to distinguish hydrogen-bearing components in shale. In this paper, we examine the relaxation characteristics of kerogen, shale, and clay minerals in continental shale under different oil or water conditions using high-resolution low-field NMR instruments (frequency is 21.36 MHz, and echo time is 0.07 ms). The NMR T 1 −T 2 map division method was established for each hydrogen-bearing component. The relaxation characteristics of each component are as follows: (1) Kerogen has the highest T 1 /T 2 ratio; oil exhibits a higher T 1 /T 2 ratio than that of water; and the mobility of water is greater than that of oil under saturated conditions. (2) The transverse relaxation time of the free state is greater than the adsorbed state for oil and water. (3) Intergranular pores of clay-rich continental shale shrink after saturation with water and result in the main peak of the T 2 value of free water at less than 1 ms, which differs from marine shale. (4) Kerogen and structural water account for a large proportion of NMR signals in continental shale. ( 5) The signals of some components in T 1 −T 2 maps overlap because of the resolution limitation of the NMR instrument. Organic matter abundance and oil saturation of shale, estimated by the NMR T 1 − T 2 map method, were in good agreement with the pyrolysis and distillation experiments, which demonstrates the reliability of the NMR T 1 −T 2 map division method for each hydrogen-bearing component in continental shale.

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