The solid powder fluorescence of oil cuttings was studied and we drawn a conclusion that in the range of certain oil concentration

the fluorescence intensity of the solid powder is linear with oil concentration in the powder of cuttings

with a regression coefficient of 0.993 6. But when the heavy oil concentration in the sample reaches a certain degree

the fluorescence intensity does not vary with oil concentration in the powder of cuttings

but its value does not equal zero. At the same time

the fluorescence quenching phenomena of oil cuttings were studied and the high concentration of heavy oil is the primary factor of the fluorescence quenching

which will causes non-linear relation between the fluorescence intensity and oil concentration in the powder of cuttings and results in false analytical data and error characters of spectra. From the study on the mechanism of concentration quenching of fluorescence

we obtained that the concentration quenching is mainly induced by the organic molecular interaction

such as formation of excimer and dimmer

intercrossing relaxation

etc. A comparison was made between the concentration quenching of solid powder fluorescence and the concentration quenching in solution. This showed that (1) when oil concentration of sample reaches a certain degree

the intensity of fluorescence keeps a constant in solid powder

but it equals zero in solution. (2) fluorescence peak of heavy oil locates at shorter wavelength in solid powder than that in solution. (3) the fluorescence quantum yield of heavy oil is larger in solid powder than that in solution. The study is important to develop a new analytical technique of quantitative fluorescence detector which can be applied to the analysis of solid samples with pretreatment

and is significance for quantitative fluo-rescence logging and organic geochemistry.