Courtillot for fruitful discussions and C. Constable for a very helpful review. This work was partly supported by grant INTAS/CNES 97-1048. INSU 'Interieur de la Terre' programme contribution No. 254 and IPGP contribution No, 1724. ,
A series expansion for angular Gaussian distribution, Appendix C, Statistics on Spheres, pp.226-231, 1983. ,
Time-dependent mapping of the magnetic field at the core-mantle boundary, Journal of Geophysical Research, vol.351, issue.B13, pp.19-537, 1992. ,
DOI : 10.1029/92JB01591
How complex is the Earth's average magnetic field?, Geophys, J. Int, vol.134, pp.527-544, 1998. ,
Anisotropic paleosecular variation models: implications for geomagnetic field observables, Earth planet. Sci. Lett, vol.115, pp.35-51, 1999. ,
Statistics of the geomagnetic secular variation for the past 5 Myr, J. geophys. Res, vol.93, pp.11-569, 1988. ,
Correlations between global features of terrestrial fields, Journal of the International Association for Mathematical Geology, vol.82, issue.2, pp.155-171, 1984. ,
DOI : 10.1007/BF01032214
Statistical Analysis of Spherical Data, 1987. ,
Persistent patterns in the geomagnetic field over the past 2.5 Myr, Nature, vol.365, issue.6449, pp.829-832, 1993. ,
DOI : 10.1038/365829a0
An analysis of the geomagnetic field over the past 2000 years, Physics of the Earth and Planetary Interiors, vol.106, issue.3-4, pp.311-315, 1998. ,
DOI : 10.1016/S0031-9201(97)00115-5
On the interpretation of virtual geomagnetic pole (VGP) scatter curves, Physics of the Earth and Planetary Interiors, vol.95, issue.1-2, pp.37-53, 1996. ,
DOI : 10.1016/0031-9201(95)03106-5
A statistical approach to the Earth's main magnetic field, Physics of the Earth and Planetary Interiors, vol.82, issue.3-4, pp.167-183, 1994. ,
DOI : 10.1016/0031-9201(94)90070-1
The time-averaged geomagnetic field as recorded by lava flows over the past 5 Myr, Geophysical Journal International, vol.122, issue.2, pp.489-519, 1995. ,
DOI : 10.1111/j.1365-246X.1995.tb07010.x
Palaeosecular Variation Recorded by Lava Flows over the past Five Million Years, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, vol.354, issue.1704, pp.89-141, 1996. ,
DOI : 10.1098/rsta.1996.0004
The time-averaged geomagnetic field: global and regional biases for 0-5 Ma, Geophysical Journal International, vol.131, issue.3, pp.643-666, 1997. ,
DOI : 10.1111/j.1365-246X.1997.tb06604.x
The geomagnetic field over the past 5 million years, Geophysical Journal International, vol.128, issue.2, pp.1-16, 1997. ,
DOI : 10.1111/j.1365-246X.1997.tb01557.x
The Fisher-Bingham distribution on the sphere, J. R. stat. Soc, vol.44, pp.71-80, 1982. ,
The Art of Computer Programming, 1981. ,
Paleosecular Variation in Field Directions Due to Randomly Varying Gauss Coefficients., Journal of geomagnetism and geoelectricity, vol.49, issue.4, pp.615-631, 1997. ,
DOI : 10.5636/jgg.49.615
Mapping the Gauss Coefficients to the Pole and the Models of Paleosecular Variation., Journal of geomagnetism and geoelectricity, vol.47, issue.1, pp.115-130, 1995. ,
DOI : 10.5636/jgg.47.115
Spherical harmonic analysis of paleomagnetic data: The case of linear mapping, Journal of Geophysical Research: Solid Earth, vol.22, issue.42, pp.5817-5833, 2000. ,
DOI : 10.1029/1999JB900050
Information Theory and Statistics, 1968. ,
The main field, in Geomagnetism, pp.249-512, 1987. ,
A study of the time-averaged paleomagnetic field for the last 195 million years, 1983. ,
Lissage et limites d'incertitude des courbes de migration polaire?pondération des données extension bivariate de la statistique de Fisher, C. R. Acad. Sci. Paris, pp.3111-1191, 1990. ,
Palaeosecular variation over the past 5 Myr based on a new generalized database, Geophysical Journal International, vol.131, issue.2, pp.240-252, 1997. ,
DOI : 10.1111/j.1365-246X.1997.tb01219.x
The timeaveraged paleomagnetic field 0-5My the Earth, J. geophys. Res, vol.101, pp.25-32, 1996. ,
The Magnetic Field of the Earth, 1996. ,
On low-degree spherical harmonic models of paleosecular variation, Physics of the Earth and Planetary Interiors, vol.95, issue.1-2, pp.55-77, 1996. ,
DOI : 10.1016/0031-9201(95)03115-4
Longterm geometry of the geomagnetic field for the last five million years: an updated secular variation database, Geophys. Res. Lett, vol.15, pp.1639-1642, 1994. ,
URL : https://hal.archives-ouvertes.fr/insu-01405155
The time-averaged paleomagnetic field, Reviews of Geophysics, vol.101, issue.824, pp.71-96, 1990. ,
DOI : 10.1029/RG028i001p00071
Permanent Aspects of the Earth's Non-dipole Magnetic Field over Upper Tertiary Times, Geophysical Journal International, vol.19, issue.4, pp.417-437, 1970. ,
DOI : 10.1111/j.1365-246X.1970.tb06056.x
Dipole Offset--The Time-Average Palaeomagnetic Field Over the Past 25 Million Years, Geophysical Journal International, vol.22, issue.5, pp.491-504, 1971. ,
DOI : 10.1111/j.1365-246X.1971.tb03616.x