Page 272 - The Geological Interpretation of Well Logs

- THE GEOLOGICAL INTERPRETATION OF WELL LOGS -

GR total OUTCROP
cps Th ppm K% 40 U ppm 14 SEDIMENTOLOGY
6
30 40 6 12 200
HIGHSTAND SYSTEMS TRACT
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TRANSGRESSIVE SYSTEMS TRACT

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metres

OUTCROP SPECTRAL GAMMA RAY

Q goniatites ® crinoids

Figure 16.1 Outcrop spectral gamma ray profile of key sequence stratigraphic surfaces including an important maximum flooding
surface (MFS). Carboniferous (Namurian), Western Ireland, SB = sequence boundary. IFS = initial flooding surface. FS = flooding
surface (data from § .Davies, modified from Davies and Elliott, 1996).

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ES laminated shale anoxic}
Figure 16.2 The Palaeocene-Eocene boundary: carbon isotope values in deep ocean cores of the North Pacific (Skatsky Rise), South
Adlaatic (Walvis Ridge) and Weddell Sea (Maude Rise) compared to gamma ray logs from a well in the Central North Sea basin.
See text for discussion (modified from Corfield and Norris, 1996 for isotopes and O’Connor and Walker, 1993 for well Jogs).
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