Table AT1. Early Maastrichtian to mid-Campanian paleomagnetic analysis, Hole 1257A.
Core, section,
interval (cm)
Depth
(mcd)
Demagnetization
(mT/°C)
Declination
(°)
Inclination
(°)
ChRM intensity
(mA/m)
Error
Polarity assignments
Comments
207-1257A-  
 
 
  
  



18X-1, 118 157.280
 
 
  
 




 
NRM 0
165.3
 68.5
7.69E–02
0.09
INT or N-type

 
AF 50
164.0
 76.8
3.37E–02
0.07
Linear, no indication of R

 
TT 150
188.8
 72.9
2.56E–02
0.04
 N?

 
TT 200
175.7
 74.3
1.87E–02
0.07


 
TT 240
143.9
 74.5
1.60E–02
0.05


 
TT 270
149.4
 73.4
1.48E–02
0.09


 
TT 300
163.9
 75.5
1.14E–02
0.18


 
TT 330
180.4
 76.9
1.19E–02
0.09


 
TT 360
160.7
 74.6
1.17E–02
0.08


 
TT 400
187.4
 70.5
1.33E–02
0.07

18X-3, 110 160.200
 
 
  
 
 
  
 

 
NRM 0
149.8
 83.9
3.42E–02
0.13


 
AF 50
186.0
 82.4
1.06E–02
0.22
Steep down, INT

 
TT 150
184.3
 67.3
6.74E–03
0.17


 
TT 150
173.4
 63.3
6.88E–03
0.26


 
TT 200
218.2
 65.1
4.38E–03
0.27
Weak after 150°C

 
TT 200
222.6
 61.5
4.11E–03
0.29
Stable DII, no decay

 
TT 240
217.4
 60.3
4.25E–03
0.19
 N?

 
TT 240
208.6
 59.6
4.38E–03
0.18


 
TT 300
216.9
 59.6
3.65E–03
0.16


 
TT 300
204.9
 66.1
3.48E–03
0.17

18X-5, 133 163.39
 
 
  
 
 
 

 
NRM 0
177.2
 78.1
5.75E–02
0.01


 
AF 50
210.7
 80.5
1.42E–02
0.05


 
TT 150
132.7
 77.8
1.35E–02
0.29


 
TT 150
130.8
 73.0
1.01E–02
0.06
Steep down, INT

 
TT 200
110.0
 61.1
9.72E–03
0.17


 
TT 200
109.0
 62.7
1.00E–02
0.07
 NPP

 
TT 240
125.0
 50.4
6.25E–03
0.21


 
TT 240
118.9
 48.8
7.04E–03
0.16


 
TT 270
126.2
 42.5
6.28E–03
0.35
Seems linear => N??

 
TT 270
123.7
 43.3
6.04E–03
0.40


 
TT 300
136.8
 59.1
4.59E–03
0.43
Weak, high errors

 
TT 300
146.6
 62.2
4.67E–03
0.30


 
TT 330
139.5
 55.9
4.11E–03
0.38


 
TT 330
135.5
 52.2
3.74E–03
0.40


 
TT 360
139.5
 42.6
3.19E–03
0.53


 
TT 400
108.8
 52.5
4.86E–03
0.25


 
TT 400
108.6
 54.0
4.51E–03
0.36

18X-7, 24 165.3
 
 
  
 
 
 

 
NRM 0
117.3
 52.6
4.82E–02
0.06
Relatively strong, and low-angle

 
AF 50
107.9
 29.6
2.50E–02
0.13
Looks N-type

 
TT 150
121.2
 19.1
2.21E–02
0.07
 N (Suganuma had NP, but Jim decided to lean towards his comments)

 
TT 200
129.4
 22.2
1.57E–02
0.07


 
TT 240
128.8
 22.5
1.43E–02
0.05


 
TT 300
130.5
 26.7
1.23E–02
0.04

19X-1, 136 166.86
 
 
  
 
 


 
NRM 0
151.2
 –29.1
2.92E–02
0.08


 
AF 50
137.6
 –56.6
2.94E–02
0.04
Begins NEGATIVE

 
TT 150
166.0
 –63
2.45E–02
0.04


 
TT 200
174.2
 –65.9
1.96E–02
0.08
General behavior looks "N"

 
TT 240
153.2
 –63.5
1.59E–02
0.04
Weird

 
TT 270
167.3
 –64.1
1.74E–02
0.12
 INT

 
TT 300
181.2
 –63.2
1.59E–02
0.09


 
TT 330
200.9
 –61.9
1.28E–02
0.09


 
TT 360
184.8
 –70.6
9.81E–03
0.13


 
TT 400
199.3
 –65.7
9.28E–03
0.11

20X-1, 26 175.46
 
 
  
 
 


 
NRM 0
345.1
 53.5
1.62E–01
0.10


 
AF 50
346.9
 37.7
8.17E–02
0.11
Nice N, essentially stable Decl NRM to 240°C

 
TT 150
343.0
 38.1
6.08E–02
0.07
 N

 
TT 200
341.6
 37.1
5.55E–02
0.10


 
TT 240
340.8
 38.6
5.39E–02
0.05


 
TT 300
334.7
 35.2
4.46E–02
0.06

Notes: NRM = natural remanent magnetization, AF = alternating-field demagnetization, TT = thermal demagnetization. Characteristic direction polarity ratings: N or R = well-defined directions computed from at least three vectors, NP or RP = less precise directions computed from only two vectors or a suite of vectors displaying high dispersion, NPP or RPP = samples that did not achieve adequate cleaning during demagnetization but their polarity was obvious, N?? or R?? = uncertain, INT = indeterminate.