Download Organic-rich Facies and Hydrocarbon Source Rocks

Fig. 11.20 A typical wireline log profile through the Upper I retaceous Brown Limestone, Gulf of Sue/, 1-gypt. The organic-rich carbonate is shown by the low density
and high sonic travel limes together with the high resistivity, (leochernicai parameters refer to the results of geochemical analyses of cuttings samples. The Brown
Limestone is separated from the underlying clastic Manilla !<>: mation by a transgressive surface, and is an organic- and phosphate-rich pelagic limestone considered to
be upwelling related. However, the high radioactivity is due lo uranium enrichment, indicating that anoxic conditions also prevailed during deposition. The overlying
Sudr Chalk Formation is organic-poor and probably represents the overlying highstand systems tract
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