CALCULATIONS AND ANALYSES OF THE HORIZONTAL GRADIENT OF THE GEOMAGNETIC FIELD
Received date: 1991-03-08
Online published: 1992-02-01
In this paper,based on the Gauss theory of geomagnetism and the spherical harmonic mi}del of the geomagnetic field,the horizontal gradients of the geomagnetic field in north一south and west-;east dlrections were calculated in Chinese and"its surrounding regions, the contour maps of the horizontal gradients of the geomagnetic components were constracted,and its regularities of distributions were analysed.
The horizontal gradients of the total intensity (F),horizontal intensity (H) and vertical intensity (Z ) vary mainly with lat<aude,it won't make much difference to vary with longitude. The horizontalgradient of the declination (D) varies not only with latitude,but also with longitude. There was maximum (absolute value) of the horizontal gradients of the horizontal intensity (H) -in the central regionof the East-Asian magnetic anomaly, and there was maximum of the horizontal gradients of the total intensity (F) in the central region of China. These phenomena merit attention.
Key words: Geomagnetic field; Horizontal gradient; Contour map.
An Zhenchang . CALCULATIONS AND ANALYSES OF THE HORIZONTAL GRADIENT OF THE GEOMAGNETIC FIELD[J]. Advances in Earth Science, 1992 , 7(1) : 39 . DOI: 10.11867/j.issn.1001-8166.1992.01.0039
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