 |
| Detailed Reference Information |
|---|
|
Morales, J., Goguitchaichvili, A. and Urrutia-Fucugauchi, J. (2003). An experimental evaluation of Shaw's paleointensity method and its modifications using late Quaternary basalts. Physics of the Earth and Planetary Interiors 138(1): 1-10. |
|
|
Absolute paleointensity experiments were carried out using Shaw's method [Geophys. J. Res. Astr. Soc. 39 (1974) 133] and its modifications [Geophys. J. Res. Astr. Soc. 54 (1978) 241; Geophys. J. Int. 80 (1985) 773; Geophys. J. Int. 118 (1994) 781] on 49 samples belonging to six Late Quaternary basaltic flows from central Mexico. Samples were selected from a large collection because of their low viscosity index, stable remanent magnetization and close to reversible continuous thermomagnetic curves. Moreover, they previously yielded high quality Thellier paleointensity results, which makes them good candidates to assess the reliability of Shaw's paleointensity method. Only 13 samples yielded acceptable results using Shaw's original method (ARM (sub 2) /ARM (sub 1) ratio varies from 0.95 to 1.05 for accepted determinations) although 6 samples do not pass the validity test proposed by Tsunakawa and Shaw [Geophys. J. Int. 118 (1994) 781] and thus should be rejected for paleointensity analyses. Rolph and Shaw's [Geophys. J. Int. 80 (1985) 773] method gives reliable determination only in one case and no single determination was obtained by Kono's [Geophys. J. Res. Astr. Soc. 54 (1978) 241] modification. Our results indicate an extremely low success rate of Shaw's paleointensity method, which may be due to magneto-chemical changes that occurred during heating of samples above their Curie temperatures. |
|
|
|
| BACKGROUND DATA FILES |
|
 |
Abstract |
 |
 |
|
Abstract |
|
|
|
|
Table 1 |
|
|
|
Table 1a |
|
|
|
Table 2 |
|
|
|
Table 1b |
|
|
|
Table 3 |
|
|
|
Table 1c |
|
|
|
|
Paleointensity Experiments |
|
|
|
|
|
Keywords
anhysteretic remanent magnetization, basalts, Cenozoic, central, Mexico, experimental studies, igneous rocks, lava flows, magnetic, intensity, magnetization, Mexican volcanic belt, Mexico, paleomagnetism, Quaternary, remanent magnetization, Shaw's method, Sierra Chichinautzin Group, Thellier Method, thermoremanent, magnetization, upper Quaternary, volcanic rocks, 24, Quaternary geology |
|
Publisher
Elsevier Science
P.O. Box 211
1000 AE Amsterdam
The Netherlands
(+31) 20 485 3757
(+31) 20 485 3432
nlinfo-f@elsevier.com |
|
|
|