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Figure F31. Composite line scan images of cores taken from the Oligocene–Miocene transition, Sites U1332, U1333, U1334, and U1336. The Oligocene/Miocene (O/M) boundary is defined by the M1a/O6 planktonic foraminifer zone boundary, here approximated at the base of the C6Cn.2n Chron at Sites U1332, U1332, and U1334 and at the lower middle part between the S. delphix biozone and the first occurrence (FO) depth of P. kugleri at Site U1336, taking account of sedimentation rate and light–dark color alternation pattern. Paleo-water depths estimated at 23 Ma. Note that an O/M boundary was also recovered at Site U1335. However, biostratigraphic control is only available for Hole 1335A where the utility of the core section images is limited by the effect of the core splitting process. These sediments are too consolidated for use of a cheese wire and too soft for use of a saw to cut whole-round core sections. Physical property data did not yet allow correlation between Holes U1335A and U1335B in these intervals. Chron is listed on the left for Sites U1332–U1334. LO = last occurrence.
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