Core and a gamma-ray log through three parasequences (B–D; see Figure 8-22 and underlying shelf facies A. The positive relationships among the percentage of sand, the facies, and permeability are shown graphically by the profiles. The contact between A and B is quite sharp, as seen on both the log and in the core. Also, Parasequence B clearly exhibits a sandier gamma-ray log response, reflecting the sandier nature of upper shoreface strata. Parasequences C and D exhibit a shalier overall log response, with alternating thin sandstones and shales reflecting the overall muddier middle to lower shoreface environment of deposition. Overall, in this well, the Terry Sandstone becomes finer-grained (muddier) upward from the base of Parasequence B, reflecting an overall temporal deepening of water during deposition. Facies 1 = Bioturbated shelf mudstone. Facies 2 = Burrowed to bioturbated sandy mudstone. Facies 3 = Burrowed to bioturbated muddy sandstone. Facies 4 = Planar- to cross-bedded sandstone. Facies 5 = Ripple-bedded sandstone. After Slatt (1997).
Reprinted with permission of Soc. Sedimentary Geology (SEPM).
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