Institute;
of;
Geology;
and;
Geophysics,;
Chinese;
Academy;
of;
Sciences,;
Beijing;
100101,;
China;
Institute;
of;
Geology;
and;
Geophysics,;
Chinese;
Academy;
of;
Sciences,;
Beijing;
100101,;
China;
geomagnetic; field,; core-mantle; boundary,; reversed; polarity; patch,; reversed; polarity; column,; polarity; reversal; of; the; geomagnetic; field.;