A theoretical analysis of the observed variability of the geomagnetic dipole field

2002 ◽  
Vol 130 (3-4) ◽  
pp. 143-157 ◽  
Author(s):  
P. Hoyng ◽  
D. Schmitt ◽  
M.A.J.H. Ossendrijver
Keyword(s):  
Theoretical Analysis ◽  
Dipole Field ◽  
Geomagnetic Dipole

scholarly journals 14C Variations During the Upper Pleistocene

Radiocarbon ◽  
1983 ◽  
Vol 25 (2) ◽  
pp. 213-218 ◽  
Author(s):  
J C Vogel
Keyword(s):  
Tree Ring ◽  
Growth Period ◽  
Dipole Field ◽  
Upper Pleistocene ◽  
The Holocene ◽  
Geomagnetic Dipole

Parallel determinations of 14C and ionium dates on a stalagmite from the Cango Caves provide evidence of variations in the 14C content of the atmosphere beyond the range of the California tree-ring sequence. During the Holocene growth period the 230Th dates are compatible with the tree-ring calibrated 14C dates. At 18,000 BP and between 30,000 and 40,000 BP the 14C ages are markedly younger than the 230Th ages, suggesting that the 14C level of the atmosphere was considerably higher at these times. Between the 230Th ages of 35,000 and 29,000 BP the 14C ages remain nearly constant at 29,500 BP, indicating that 14C production must have been drastically reduced during this period. The 14C fluctuation is greater than that predicted by Barbetti (1980) but it may be explained by postulating a substantial increase in the geomagnetic dipole field, for which there is mounting evidence.

New technique to diagnose the geomagnetic field based on the single circular current loop model

2020 ◽  
Author(s):  
Zhaojin Rong ◽  
Yong Wei ◽  
Wenyao Xu ◽  
Dali Kong ◽  
Jun Cui ◽  
...  
Keyword(s):  
Electric Current ◽  
Geomagnetic Field ◽  
Dipole Field ◽  
New Technique ◽  
Current Loop ◽  
Loop Model ◽  
Effective Technique ◽  
Circular Current ◽  
Planetary Magnetism ◽  
Geomagnetic Dipole

<p>A quick and effective technique is developed to diagnose the geomagnetic dipole field based on an unstrained single circular current loop model. In comparsion with previous studies, this technique is able to separate and solve the loop parameters successively. With this technique, one can search the optimum full loop parameters quickly, including the location of loop center, the loop orientation, the loop radius, and the electric current carried by the loop, which can roughly indicate the locations, sizes, orientations of the interior current sources. The technique tests and applications demonstrate that this technique is effective and applicable. This technique could be applied widely in the fields of geomagnetism, planetary magnetism and palaeomagnetism. The further applications and constrains are discussed and cautioned.</p>

Sign in / Sign up

Export Citation Format

Share Document