Figure F4. Magnetic polarity data (inclination after 25-mT demagnetization on the shipboard pass-through magnetometer) and stable isotope data (based on the benthic foraminifer Cibicidoides mundulus) vs. depth in Core 202-1237B-31H. Also shown are interpreted paleomagnetic Chrons 7Ar to 9n and last occurrence (LO) of the calcareous nannofossil Sphenolithus distentus (Shipboard Scientific Party, 2003) and LO of the planktonic foraminifer Paragloborotalia opima (this study). The late Oligocene climate transition occurs as a three-step decrease in delta18O within Chron 8r (here termed the "Chron 8r delta18O shift"), immediately following Oi2b of Miller et al. (1991). VPDB = Vienna Peedee belemnite.

Figure F4. Magnetic polarity data (inclination after 25-mT demagnetization on the shipboard pass-through magnetometer) and stable isotope data (based on the benthic foraminifer Cibicidoides mundulus) vs. depth in Core 202-1237B-31H. Also shown are interpreted paleomagnetic Chrons 7Ar to 9n and last occurrence (LO) of the calcareous nannofossil Sphenolithus distentus (Shipboard Scientific Party, 2003) and LO of the planktonic foraminifer Paragloborotalia opima (this study). The late Oligocene climate transition occurs as a three-step decrease in

¹⁸O within Chron 8r (here termed the "Chron 8r

¹⁸O shift"), immediately following Oi2b of Miller et al. (1991). VPDB = Vienna Peedee belemnite.