An NMR sensor and method is disclosed for analyzing a core sample from a subsurface formation. Embodiments of the method utilize two or more magnets disposed proximate to each other. The configuration of the magnets allows for increased detection frequency, and creates a strong field with much finer resolution than existing designs. In addition, embodiments of the sensor may be used at the well site due to its small size and simple hardware. Further details and advantages of various embodiments of the method are described in more detail herein.