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Table T15. Biostratigraphic and magnetostratigraphic datums, Hole U1408A.

Datum tie
point 		Datum Datum type Zone/Subzone Age
(Ma) 		Depth (mbsf)
Top Bottom Mid-point
D01 Ba Emiliania huxleyi Calcareous nannofossil NN21 0.29 0.75 2.25 1.50
  T Pseudoemiliania lacunosa Calcareous nannofossil NN20 0.44 4.33 8.30 6.32
  T Discoaster brouweri Calcareous nannofossil NN19 1.93 8.30 9.80 9.05
D02 T Discoaster hamatus Calcareous nannofossil NN10 9.53 9.80 11.30 10.55
  T Catinaster coalitus Calcareous nannofossil   9.69 9.80 11.30 10.55
  B Discoaster hamatus Calcareous nannofossil   10.55 11.30 13.87 12.59
D03 B Catinaster calyculus Calcareous nannofossil   10.79 11.30 13.87 12.59
D04 B Sphenolithus distentus Calcareous nannofossil   30.00 27.31 28.81 28.06
  T Reticulofenestra umbilicus (>14 μm) Calcareous nannofossil NP23 32.02 27.31 28.81 28.06
  T Coccolithus formosus Calcareous nannofossil NP22 32.92 27.31 28.81 28.06
D05 T Chiasmolithus grandis Calcareous nannofossil   37.98 28.81 28.81 28.81
  B Dictyococcites bisectus (>10 μm) Calcareous nannofossil   40.36 63.81 65.31 64.56
  T Chiasmolithus solitus Calcareous nannofossil NP17 40.40 60.31 61.94 61.13
  B Reticulofenestra reticulata Calcareous nannofossil   41.66 98.22 99.27 98.75
  T Nannotetrina spp. Calcareous nannofossil   41.85 108.53 118.84 113.69
  B Reticulofenestra umbilicus (>14 μm) Calcareous nannofossil   41.94 128.20 130.31 129.25
  T Nannotetrina fulgens Calcareous nannofossil   42.87 130.31 137.61 133.96
  T Chiasmolithus gigas Calcareous nannofossil NP15c 44.12 150.55 153.92 152.24
  B Sphenolithus furcatolithoides Calcareous nannofossil     182.74 192.73 187.73
  B Chiasmolithus gigas Calcareous nannofossil NP15b 45.49 199.49 202.25 200.87
D15 B Nannotetrina fulgens Calcareous nannofossil NP15a 46.29 223.21 224.70 223.96
  B Nannotetrina cristata Calcareous nannofossil   47.73 223.21 224.70 223.96
  T Discoaster lodoensis Calcareous nannofossil   47.41 223.21 224.70 223.96
  B Discoaster sublodoensis (5 rayed) Calcareous nannofossil NP14 49.11 224.70 226.00 225.35
  B Dictyococcites/Reticulofenestra Calcareous nannofossil   50.50 223.21 224.70 223.96
D17 T Tribrachiatus orthostylus Calcareous nannofossil NP13 50.50 224.70 226.00 225.35
D18 T Toweius spp. Calcareous nannofossil   50.78 224.70 226.00 225.35
D19 B Discoaster lodoensis Calcareous nannofossil NP12 53.70 227.64 228.12 227.88
  T Tribrachiatus contortus Calcareous nannofossil NP11 54.17      
  B Sphenolithus radians Calcareous nannofossil   54.17      
  B Tribrachiatus orthostylus Calcareous nannofossil   54.37 228.12 228.34 228.23
  B Discoaster diastypus Calcareous nannofossil   54.95 228.85 229.27 229.06
  T Fasciculithus spp. Calcareous nannofossil   55.64 229.36 229.44 229.40
  B Rhomboaster bramlettei Calcareous nannofossil NP10 55.86 229.44 229.49 229.47
  Fasciculithus diversity decline Calcareous nannofossil   56.00 229.93 229.93 229.93
D20 T Fasciculithus alanii Calcareous nannofossil   56.00 229.65 229.93 229.79
  T Ericsonia robusta (>9 μm) Calcareous nannofossil   57.10 232.38 243.88 238.13
D21 B Discoaster multiradiatus Calcareous nannofossil NP9 57.21 243.88 245.19 244.54
  Tc Sphenolithus anarrhopus Calcareous nannofossil     243.88 246.59 245.23
  B Discoaster delicatus Calcareous nannofossil   57.45 245.19 246.59 245.89
  B Ericsonia robusta (>9 μm) Calcareous nannofossil   57.54 245.19 246.59 245.89
  Tc Discoaster backmanii Calcareous nannofossil   57.57 243.88 245.19 244.53
  B Discoaster backmanii Calcareous nannofossil   58.28 246.59 246.59 246.59
D22 B Discoaster mohleri Calcareous nannofossil NP7 58.97 246.59 246.59 246.59
  T Calocyclas trichopa Radiolarian   43.38 144.29   144.29
  T Podocyrtis dorus Radiolarian RP13 43.81 145.09 150.50 147.80
  B Calocyclas trichopa Radiolarian   44.46 150.50   150.50
  T Amphisphaera goruna Radiolarian   55.50 227.85 231.85 229.85
  X Bekoma campechensis - B. bidartensis Radiolarian RP7 58.23 246.59   246.59
  T Orbulinoies beckmani Planktonic foraminifer E13/E12 40.03 50.40 51.68 51.04
  B Orbulinoies beckmani Planktonic foraminifer E12/E11 40.43 57.30 58.80 58.05
  T Guembelitrioides nuttalli Planktonic foraminifer E11/E10 42.07 73.30 74.80 74.05
  T Morozovella aragonensis Planktonic foraminifer E10/E9 43.26 137.57 138.51 138.04
  B Globigerinatheka kugleri Planktonic foraminifer E9/E8 43.88 163.33 165.78 164.56
  B Guembelitrioides nuttalli Planktonic foraminifer E8/E7 45.72 215.82 220.20 218.01
  T Globanomalina pseudomenardii Planktonic foraminifer P4/P5 57.10 238.88 243.87 241.38
D6 C17n.3n/C17r Chron boundary   38.33     29.39
D7 C17r/C18n.1n Chron boundary   38.62     30.63
D8 C18n.1n/C18n.1r Chron boundary   39.63     48.70
D9 C18n.2n/C18r Chron boundary   40.14     59.30
D10 C18r/C19n Chron boundary   41.15     73.77
D11 C19n/C19r Chron boundary   41.39     75.38
D12 C19r/C20n Chron boundary   42.30     101.21
D13 C20n/C20r Chron boundary   43.43     139.07
D14 C20r/C21n Chron boundary   45.72     212.60

T = top, Tc = top common, B = base, Ba = base of acme, X = faunal crossover.

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