Table T3. Paleomagnetic data for igneous samples, Site 581.
Core, section, interval (cm)
Depth (mbsf)
NRM
(A/m)
Inc
(°)
Demag
N
Steps
MAD
(°)
Colatitude (°)
Group number
Mean colat
Std
N colat
581-        
 
 
    
 
    
 
19-1, 72 343.72 1.2 -0.5
T
7
350-500
 7.0 90.2
 
    
 
19-1, 108 344.08 2.5 2.9
T
4
375-450
 3.7 88.6
 
    
 
19-1, 116 344.16 1.0 6.9
T
6
375-500
 3.4 86.5
 
    
 
19-2, 123 345.73 2.0 3.7
A
4
15-30
 1.0 88.1
 
    
 
19-3, 90 346.90 3.9 2.6
A
4
10-35
 1.5 88.7
 
    
 
19-3, 127 347.27 2.4 -17.2
T
4
200-375
 10.8 98.8*
 
    
 
19-4, 19 347.69 4.1
Unstable
T
 
 
    
 
    
 
19-4, 36 347.86 3.6 0.6
A
4
10-25
 1.2 89.7
1
 88.6 1.3
6
581A-        
 
 
    
 
    
 
3-1, 38 355.88 2.8 23.0
T
5
400-500
 4.3 78.0
 
    
 
3-1, 86 356.36 3.5 17.2
T
5
300-475
 8.1 81.2
 
    
 
3-1, 126 356.76 2.7 21.9
T
6
350-500
 5.2 78.6
 
    
 
3-2, 11 357.11 6.8 14.2
T
6
325-450
 6.2 82.8
 
    
 
3-2, 81 357.81 7.9 50.1
T
6
350-475
 8.9 59.1*
 
    
 
3-2, 111 358.11 13.9 20.6
A
7
20-50
 2.1 79.4
 
    
 
3-3, 8 358.58 5.5 10.3
T
6
375-500
 5.7 84.8
 
    
 
3-3, 92 359.42 2.7 15.7
T
3
350-400
 5.8 82.0
 
    
 
3-3, 147 359.97 5.1 26.1
T
5
250-375
 5.4 76.2
 
    
 
3-4, 14 360.14 6.4 27.6
T
6
375-500
 2.2 75.4
1
 79.8 3.1
9
581B- (negative inclinations assumed reversed polarity)
1-1, 19 347.69 1.0 -30.0
T
5
375-500
 5.7 73.9
 
    
 
1-1, 93 348.43 0.8 -32.2
T
6
375-500
 5.8 72.5
 
    
 
2-1, 35 347.85 2.3 -36.2
T
5
375-500
 6.5 69.9
 
    
 
2-1, 55 349.55 0.8 -30.2
T
4
425-500
 6.8 73.8
 
    
 
2-1, 121 350.21 1.3 -39.3
T
4
400-475
 7.2 67.7
 
    
 
2-2, 28 350.78 1.7 -32.5
T
5
375-475
 8.7 72.3
 
    
 
2-2, 76 351.26 1.5 -20.8
T
4
375-450
 4.2 79.2
1
 107.2 3.6
7
2-3, 7 352.07 1.1 -3.6
T
4
375-450
 5.7 88.2*
2
 91.8  
1
2-3, 127 353.27 4.0 -18.3
T
6
375-500
 3.2 80.6
 
    
 
2-3, 142 353.42 8.8 -26.1
T
4
425-500
 6.6 76.2
 
    
 
2-4, 18 353.68 2.5 -31.9
T
5
400-500
 6.0 72.7
3
 103.5 4.0
3
2-4, 52 354.02 3.1 -27.0
T
4
375-450
 5.7 75.7
 
    
 
2-4, 60 354.10 3.7 -12.6
T
6
375-500
 6.3 83.6
 
    
 
2-4, 91 354.41 4.3 -7.3
T
6
375-500
 2.2 86.3
 
    
 
2-4, 107 354.57 2.1 -5.5
A
4
30-45
 8.0 87.2
 
    
 
2-4, 140 354.90 3.3 -19.0
T
5
375-475
 5.9 80.2
4
 97.4 4.7
5
2-5, 91 355.91 4.7 -48.8
T
4
425-500
 5.6 60.3*
5
 119.7  
1
2-5, 123 356.23 4.4
Unstable
T
 
 
    
 
    
 
2-5, 133 356.33 6.6
Unstable
T
 
 
    
 
    
 
3-2, 33 360.63 2.1 -30.8
T
4
425-500
 11.4 73.4
 
    
 
3-2, 105 361.35 3.9 -4.5
T
5
325-500
 8.9 87.7
 
    
 
3-2, 137 361.67 2.8 24.5†
A
5
15-35
 1.8 77.2
 
    
 
3-3, 12 361.92 3.4 -19.5
A
4
35-50
 14.4 80.0
6
 100.4 6.1
4
4-1, 76 367.06 1.4 -1.9
A
5
25-45
 5.3 89.1
 
    
 
4-1, 130 367.60 2.8 0.4
A
6
20-45
 2.6 89.8
 
    
 
4-2, 71 368.51 6.0 5.6
A
4
20-40
 2.0 87.2
7
 89.3 1.9
3
4-2, 139 369.19 2.0
Unstable
T
 
      
 
    
 
4-3, 14 369.44 2.7 -22.9
T
5
400-500
 4.7 78.1*
8
 101.9  
1
581C-                
 
    
 
1-1, 68 358.28 5.1 16.7
T
5
200-350
 2.5 81.5
 
    
 
1-1, 120 358.80 5.6 14.7
T
4
425-500
 4.3 82.5
 
    
 
2-1, 7 359.67 5.5 -19.8†
T
4
425-500
 5.1 79.8
 
    
 
2-1, 71 360.31 3.9 24.1
T
5
350-450
 3.9 77.4
 
    
 
2-1, 98 360.58 5.1 32.8
T
5
375-475
 6.2 72.1
 
    
 
2-1, 117 360.77 5.3 31.2
T
6
375-500
 3.4 73.2
1
 77.7 4.3
6
2-2, 85 361.95 3.9 22.2
T
8
325-500
 2.9 78.5
 
    
 
2-2, 104 362.14 2.7 -2.2†
T
5
375-475
 5.6 88.9
 
    
 
2-2, 124 362.34 4.3 14.8
T
4
325-400
 1.5 82.5
 
    
 
2-2, 132 362.42 7.0 -17.7†
T
4
350-425
 5.8 80.9
 
    
 
2-3, 48 363.08 5.0 18.2
T
6
350-475
 1.7 80.7
 
    
 
2-3, 68 363.28 4.0 8.0
T
6
325-450
 3.1 86.0
 
    
 
2-3, 109 363.69 5.2 15.2
T
5
375-475
 1.2 82.3
2
 82.8 4.3
7
2-4, 79 364.89 3.2 24.1
T
6
300-425
 9.7 77.4
 
    
 
2-4, 100 365.10 6.0 26.1
T
4
250-325
 8.2 76.2
 
    
 
2-4, 121 365.31 3.7
Unstable
T
 
 
    
 
    
 
2-5, 28 365.88 4.3
Unstable
T
 
 
    
 
    
 
2-5, 62 366.22 3.4 -20.9†
T
4
400-475
 6.9 79.2
 
    
 
2-5, 125 366.85 3.4 28.9
T
4
300-375
 7.7 74.6
 
         
3-1, 42 369.22 3.4 26.1
T
5
325-425
 2.6 76.2
 
    
 
3-1, 141 370.21 1.9 18.5
T
6
350-475
 4.9 80.5
 
    
 
3-2, 54 370.84 3.5 23.8
T
6
300-425
 4.0 77.6
 
    
 
3-2, 81 371.11 1.9 12.4
T
6
300-425
 3.3 83.7
 
    
 
3-3, 14 371.94 3.5 22.9
T
8
300-475
 2.7 78.1
 
    
 
3-3, 74 372.54 1.7 20.4
T
6
275-400
 5.0 79.5
 
    
 
3-3, 110 372.90 2.0 23.1
T
6
325-500
 6.7 78.0
 
    
 
3-4, 66 373.96 4.9 25.4
T
5
400-500
 3.9 76.6
 
    
 
3-4, 99 374.29 3.6 13.4
T
5
375-500
 2.4 83.2
 
    
 
3-4, 107 374.37 7.2 39.3
T
6
350-475
 4.0 67.7*
 
    
 
3-4, 116 374.46 9.3 25.1
T
5
375-500
 1.7 76.8
 
    
 
3-4, 141 374.71 4.3 49.3
T
6
350-475
 1.9 59.8*
 
    
 
3-5, 27 375.07 3.8 14.8
T
4
375-475
 2.1 82.5
 
    
 
3-5, 60 375.40 8.1 6.9
T
6
375-500
 6.3 86.5
 
    
 
3-5, 80 375.60 2.6 21.3
T
4
325-400
 4.9 79.0
 
    
 
3-5, 127 376.07 4.2 51.2
T
5
300-400
 2.1 58.1*
 
    
 
3-5, 132 376.12 2.5 45.6
T
4
325-400
 3.5 63.0*
 
    
 
3-5, 137 376.17 3.2 15.8
T
5
325-425
 4.1 81.9
 
    
 
3-5, 141 376.21 3.3 6.2
T
4
300-375
 1.1 86.9
3
 80.0 3.6
19

Notes: NRM = natural remanent magnetization. Inc = inclination of characteristic remanent magnetization determined by principal component analysis. Demag = demagnetization. A = alternating field, T = thermal. N = number of measurements used for principal component analysis. Steps = demagnetization steps used for principal component analysis. MAD = maximum angle of deviation (Kirshvink, 1980). Mean colat = group mean colatitude. Std = standard deviation of group mean colatitude. N colat = number of colatitudes used to calculate group mean. * = datum not used in average colatitude calculations. Group averages are shown at the far right; underscores show the division of groups. † = sample showing anomalous inclinations (see text).