The basic principle of radioisotope X-ray fluorescence logging technique has been described.Some practical methods for correcting unevenness effects

drilling fluid effects and matrix effects are presented.A test on strontium deposit showed that relative errors between thicknesses and average ore grades of the strontium seams determined by X-ray fluorescence logging and by traditional core-chemical analysis are less than 10%

which can meet the requirments of reserve calculation standard.It is also shown that the consuming time for X-ray fluorescence logging is much less than that for traditional methods.