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The effects of the variation of the dimensionless strong interactionparameter Xq=mq/Lambda{QCD} (mq is the quark mass, Lambda{QCD} is the QCDscale) are enhanced about 1.5 x 10**5 times in the 7.6 eV "nuclear clock"transition between the ground and first excited states in the 229Th nucleus andabout 1 x 10**8 times in the relative shift of the 0.1 eV compound resonance in150Sm.The best terrestrial limit on the temporal variation of the fundamentalconstants, |delta(Xq)/Xq| < 4 x 10**-9 at 1.8 billion years ago (|d(Xq/Xq)/dt|< 2.2 x 10**-18 y**-1), is obtained from the shift of this Sm resonance derivedfrom the Oklo natural nuclear reactor data. The results for 229Th and 150Sm areobtained by extrapolation from light nuclei where the many-body calculationscan be performed more accurately. The errors produced by such extrapolation maybe smaller than the errors of direct calculations in heavy nuclei. Theextrapolation results are compared with the "direct" estimates obtained usingthe Walecka model. A number of numerical relations needed for the calculationsof the variation effects in nuclear physics and atomic spectroscopy have beenobtained: for the nuclear binding energy delta(E)/E ~ -1.45 delta(mq)/mq, forthe spin-orbit intervals delta(Eso)/Eso ~ -0.22 delta(mq)/mq, for the nuclearradius delta(r)/r ~ 0.3 delta(mq)/mq (in units of Lambda{QCD}); for the shiftsof nuclear resonances and weakly bound energy levels delta(Er) ~ 10delta(Xq)/Xq MeV.

Enhanced effect of quark mass variation in 229Th and limits from Oklo data