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Experimental results show that skarns can--800℃ and 500--1,000 bars. Starting materialsinclude intermediate-acidic igneous rocks, volcanic rocks, metamorphic rocks, carbonates of va-rious purities and chemical reagents of analytical purity-grade. Experimental media are: NaCI,NaCl + CaCl_2, NaCl + CaCl_2 + MgCl_2, Na_2CO_3 and Na_2SiO_3 solutions. Experimental results show that skarns can be formed under wide physico-chemical condi-tions: T=400°--800℃, P=500--1,000 bars, pH=4--11, and fo_2=10~(-23)--10~(-11) bar. The mineralogyof skarns and the chemical compositions of skarn minerals are generally controlled by the com-bined factors: the chemical composition of the original rocks, pH values, redox conditions,temperatures and pressures. Isomotphous substitution may have agreat effect on the temperatu-re of formation and fo_2 of some major skarn minerals. It is found that skarnization occurs pre-ferentially in NaCl and NaCl+CaCl_2 solutions and subortinately in MaCO_3 and Na_2SiO_3 soiu-tions.
Starting materialsinclude intermediate-acidic igneous rocks, volcanic rocks, metamorphic rocks, carbonates of va-rious purities and chemical reagents of analytical purity-grade. Experimental media are: NaCI, NaCl + CaCl_2, NaCl + CaCl_2 + MgCl_2, Na_2CO_3 and Na_2SiO_3 solutions. Experimental results show that skarns can be formed under wide physico-chemical condi- tions: T = 400 ° -800 ° C, P = 500-1,000 bars , pH = 4--11, and fo_2 = 10 ~ (-23) -10 ~ (-11) bar. The mineralogy of skarns and the chemical compositions of skarn minerals are generally controlled by the com-bined factors: the chemical composition of the original rocks, pH values, redox conditions, temperatures and pressures. Isomotphous substitution may have agreat effect on the temperatu-re of formation and fo_2 of some major skarn minerals. It is found that skarnization occurs pre-ferentially in NaCl and NaCl + CaCl_2 solutions and subortinately in MaCO_3 and Na_2SiO_3 s oiu-tions.