The results of the detection and study of quasi-Chandler wobble in geo
magnetic observations are discussed. The conclusion on the similarity
of the structure and character of the variation of the amplitudes and
phases of Chandler and quasi-Chandler periods has been drawn. Statisti
cal connection between the variation of Chandler-wobble amplitude and
nontidal irregularities of the Earth's rotation is established. The 10
0-year series of observations are used for the investigation.