Tracer (Sr and delta 18 O) studies on 170 carbonate rocks indicate that diagenetic transformation of the metastable into a stable carbonate assemblage involves a partially closed wet chemical system. If the assumptions about present-day counterparts of Mesozoic facies are correct, the following tracer redistribution is indicated: (1) calcite is relatively stable and the decrease in Sr is < or = 5 x and the delta 18 O negative shift is nearly equal 0-2.5 per thousand ; (2) aragonite and Mg-calcites are reprecipitated with varying efficiency as autochthonous calcite, which results in nearly equal 10 x Sr decrease and delta 18 O negative shift of nearly equal 1-5 per thousand . Strontium content of dolomites decreases with geologic age, because of reduction in available lattice positions due to the Fe substitution.

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