Figure F16. A. Distribution of porosity and its dependence on fragment size in cuttings samples and comparison with discrete core samples, Site C0020. In general, porosity decreases with an increase in cuttings fragment size at the same depth. Notice that discrete core samples measured for physical properties are 20 mm length cubic shape. B. Distribution and lithologic variation of porosity in discrete core samples and comparison with cuttings. Sandstone and siltstone porosity gradually decreased with depth, though carbonate-cemented rocks deviate from the consolidation curve with remarkably low porosity. Coal porosity does not deviate from that of sedimentary rocks. Higher porosity and slower reduction in porosity with depth is observed in cuttings samples. Discrete core samples can be more representative of in situ porosity than the porosity of cuttings. Note that cuttings data plotted on B is the >4 mm fraction.
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