Figures 11 and 12. Scanning electron microscopy is one type of petrographic  analysis used to describe the tight-oil unconventional shale core and determine the most effective programs for reservoir exploitation. Figures 13, 14, and 15. Thin-section microphotographs of fractures in the Bakken reservoir. Figure 16. Core’s petrophysical models are used to correct errors  inherent in wireline logs.