This thesis presents a fundamental research on unconventional formations where it has been empirically observed that the saturating hydrocarbons have higher Nuclear Magnetic Resonance (NMR) T1/T2 ratio than saturating water. This empirical rule has been exploited as a powerful logging technique for oil and gas industry. But the origin of the high T1/T2 ratio were not clearly understood until now. This research confirms that the saturating heptane in kerogen has higher T1/T2 ratio than water in kerogen and clays, which validates the fluid typing technique providing the wettability. This research also proves that the origin of the high T1/T2 ratio observed on heptane is that the heptane absorbed in kerogen and/or bitumen, where the relaxation mechanism involves the 1H-1H dipole-dipole interaction. The findings in this thesis provide key insight into the high T1/T2 ratio, which can be used to improve the interpretation of NMR logs in terms of fluid typing and saturation estimation.