Geomagnetic field

CUT-OFF OF LOWER ENERGY PARTICLES BY GEOMAGNETIC FIELD (TIME variations)... 

Magnetotaxis is orientation and migration along geomagnetic field lines. 

Frank M., Schwaz B., Baumann S., Kubik P.W., Suter M., and Mangini A. (1997) A 200 kyr record of cosmogenic radionuclide production rate and geomagnetic field intensity from lOBe in globally stacked deep-sea sediments. Earth Planet Sci. Lett. 149, 121-129. 

In Table 7.2, we summarize major He fluxes in the atmosphere. The He budget seems to be in balance, at least within a factor of two, although there is certainly room for modification of some of the terms or introduction of new ones. However, there is no reason to require the He budget to be in balance. On the 106 year scale of the mean residence time, variations in fluxes will be smoothed out, and the present epoch may not be typical. The geological and cosmic ray sources are probably fairly steady on this time scale, but the thermal loss is very sensitive to solar activity, the nonthermal loss is sensitive to the geomagnetic field, and precipitation is sensitive to both. At an extreme, the fluxes may be highly irregular Sheldon and Kern (1972),... 

Presdi, D. Pettigrew, J.D. Ferromagnetic coupling to muscle receptors as a basis for geomagnetic field sensitivity in animals. Nature 1980, 285, 99-101. 

Significant deficiencies are present in the physical dating methods used to infer temporal relationships for the paleoanthropological and archaeological record for the whole of the Middle Pleistocene (about 730,000 to 125,000 B.P.) (11), and for the interval of time up to the initiation of the 14C time scale. There are no recognized major reversals of the earth s geomagnetic field after 730,000 years ago. Many important sites are not in areas of vol-canism, and even for those that are, there are often serious analytical prob-... 

The moment of concrescence may occupy the same position with respect to time that a magnetic pole of the earth occupies relative to the geomagnetic field of the planet. Like the poles, which are physically characterized by climatological extreme, the temporal pole would mark a temporal extreme, the most extreme moment of density of the ingression of novelty, but like the poles, it would not be apparently different from its space-time environment. Such an understanding of time would mean no definitive concrescence could take place. 

The composition of the Earth s core is a fundamental issue in the study of the Earth. It is directly linked to the volatile element budget of the bulk Earth, the conditions and mechanisms of core formation, the nature and dynamics of coremantle interaction, and the origin and evolution of the geomagnetic field. 

National Oceanic and Atmospheric Administration - National Geophysical Data Center, 2000, Geomagnetic Field Synthesis Program (GeoMAG) http //www.ngdc.noaa.gov/seg/potfld/faqgeom.html. 

FIGURE 8.8 Photomicrographs of chain-like agglomerates (a) chain-like agglomerates of hematite particles in the presence of the geomagnetic field (b) in the absence of the field. 

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