Table 1.

Magnetostratigraphic calibrations of nannofossil datums from high and mid-latitude sites.* (converted to Gradstein et al. 2004, timescale)

Eocene and Oligocene Nannofossil DatumsHsü et al. (1984), Site 522Parker et al. (1985), Site 558Backman, (1986a), Site 528Backman, (1986b), Site 577§Backman (1987), Sites 522 and 523Wei & Wise (1989) Site 5161Thomas et al. (1990), Site 689Thomas et al. (1990), Site 690Marino & Flores (2002), Site 10902Roberts et al. (2003), Sites 744 and 748Stickley et al. (2004); Site 1168Stickley et al. (2004); Site 1170Stickley et al. (2004); Site 1172Agnini et al. (2007); Site 1262Predicted mean ages in Hole 647APredicted age ranges in Hole 647A
Age references of nannofossil datums from middle and high latitudesAge (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)
LO S. ciperoensis28.727.427.127.927.1–28.7
HO R. umbilicus (>14 µm)31.932.731.131.631.533.032.031.1–33.0
LO S. distentus33.533.533.5
HO I. recurvus32.932.833.933.033.432.8–33.9
HO E. formosa32.933.133.032.9–33.1
HO D. saipensis34.434.134.334.334.1–34.4
HO D. barbadiensis34.634.434.534.4–34.6
HO R. reticulate35.035.036.136.135.535.0–36.1
LO R. bisecta (>10 µm)39.639.439.5–40.439.939.4–40.4
HO C. solitus38.138.039.738.038.438.838.0–39.7
LO R. reticulate40.539.741.040.441.138.039.339.638.0–41.1
HO Nannotetrina cristata ( = HO N. spp.)40.940.940.940.9
LO R. umbilicus (>14 µm)41.241.541.141.842.942.041.1–42.9
HO C. gigas41.541.541.5
LO C. gigas44.044.044.0
HO D. lodoensis48.048.048.0
HO T. orthostylus50.950.951.0
LO D. lodoensis52.353.552.952.3–53.5
LO T. orthostylus53.953.954.254.053.9–54.2
Thomas et al. (1990), Site 689 nannofossil dataMid-point Depth of datumChrons surrounding datumChron Depths surrounding datum% Datum Depth>upper Chron DepthChron ages surrounding datum (Ma)Datum Age (Ma)
HO R. umbilicus (>14 µm)106.55Top C12n104.380.8730.62731.05
Base C12n106.8831.116
HO C. solitus153.15Top C17n.1n135.770.9736.51237.99
Top C18n.1n153.7038.032
LO R. reticulata158.96Top C18n.1n153.700.6738.03239.65
Top C19n161.5440.439
LO R. umbilicus (>14 µm)164.37Base C19n163.160.5140.67141.14
Top C20n165.5541.590
Thomas et al. (1990), Site 690 nannofossil Data
HO I. recurvus89.91Base C12n84.010.5031.11633.72
Base C16n.2n95.7036.276
HO R. umbilicus (>14 µm)84.92Base C12n84.010.0831.11631.52
Base C16n.2n95.7036.276
LO R. reticulata105.85Base C19n105.650.3240.67140.97
Top C20n106.2741.590
LO R. umbilicus (>14 µm)108.30Top C20n106.270.1741.59041.79
Base C20n118.2342.774
HO D. lodoensis127.55Base C21n123.630.5747.23548.02
Top C22n130.4848.599
LO D. lodoensis135.66Base C23n.2n133.180.6051.90152.35
Top C24n.1n137.3352.648
Parker et al. (1985), Site 558 nannofossil data
LO S. ciperoensis146.32Top C9n137.700.6126.7127.40
Base C9n151.7727.83
Oligocene diatom dataSchrader & Fenner (1976), Site 338Roberts et al. (2003), Site 744Roberts et al. (2003), Site 748Gersonde et al. (1999); ODP Leg 177 IRPredicted mean ages in Hole 647APredicted age ranges in Hole 647A
Age references of diatom datums from middle and high latitudesAge (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)Age (Ma)
LO Rhizosolenia gravida/oligocaenica33.7933.9833.4233.7033.42–33.98
LO Synedra jouseanus30.9931.130.7830.9430.78–31.10
HO Sceptroneis pupa31.12–33.2732.1931.12–33.27
LO Sceptroneis pupa31.12–33.2732.1931.12–33.27
  • HO, highest occurrence; LO, lowest occurrence.

  • LO S. ciperoensis correlated to base C10n.2n.

  • Parker et al.'s (1985) more thorough analysis of nannofossils places the LO S. ciperoensis clearly at the base of Section 22-CC, not in Section 23-5 as reported by Bukry (1985) and Miller et al. (1985).

  • §Backman's (1986a, b) datum for the HO of T. orthostylus is from Site 577, which was in the tropics during the Paleocene to Early Eocene; however it is the only magnetostratigraphically correlated age for this datum.

  • HO Nannotetrina spp.; LO of D. hesslandii (equivalent to R. bisecta).

  • 1HO Nannotetrina fulgens.

  • 2 LO R. bisecta between top and base of C18r.

  • *Mean age values and errors based on maximum and minimum reported ages are calculated when data are available from multiple sites.

  • Khan et al. (1985).

  • Calibrated to Eldrett et al. (2004).