|
Detailed Reference Information |
Yang, Z., Moreau, M., Bucher, H., Dommergues, J. and Trouiller, A. (1996). Hettangian and Sinemurian magnetostratigraphy from Paris Basin. Journal of Geophysical Research 101: doi: 10.1029/95JB03717. issn: 0148-0227. |
|
A long core (1110 m) drilled at Montcornet (northeastern Paris Basin) provides early Jurassic magnetostratigraphic data coupled with biochronological control. About 600 paleomagnetic samples were obtained from a 148-m-thick series of Hettangian and Sinemurian rocks. A composite demagnetization using thermal (up to 300 ¿C) followed by alternating field technique (up to 100 mT) is used to separate the magnetic components. A low unblocking temperature component (<250 ¿C) with an inclination of about 65¿ is interpreted as a present-day field overprint. The characteristic remanent component with both normal and reversed antipodal directions is then isolated between 5 and 70 mT. Eighty-one polarity intervals are recognized in this study. The higher reversal frequency of the late Hettangian/early Sinemurian time interval contrasts with a lower reversal rate observed in the rest of the early Liassic. A rough mean estimate of about 5 reversals/m.y. can be proposed for the earliest Jurassic. These results represent a significant contribution to the magnetic polarity reversal timescale for a time interval hitherto poorly known and add to the magnetic reversal frequency curve of the last 350 m.y. ¿ American Geophysical Union 1996 |
|
DATABASE QUICK LINKS |
|
|
MagIC Database |
|
|
|
|
|
BACKGROUND DATA FILES |
|
|
Abstract |
|
|
|
|
MagIC SmartBook v1 |
|
|
|
|
|
Keywords
Geomagnetism and Paleomagnetism, Paleomagnetic secular variation |
|
Publisher
American Geophysical Union 2000 Florida Avenue N.W. Washington, D.C. 20009-1277 USA 1-202-462-6900 1-202-328-0566 service@agu.org |
|
|
|