Experimental modeling of barogradient systems

A system with a barogradient fluid how of the C-O-H composition with variab le proportions of the components was studied experimentally on original equ ipment. The proposed technique makes it possible to model barogradient proc esses of interaction between fluid and rocks and minerals under isothermal conditions with allowance for variations in the porosity and permeability w ith a maximum fluid pressure gradient of 500 bar/cm. The diameter of the sa mples varies from 10 to 25 mm; the rate of fluid flow ranges from 10(-8) to 10(-5) cm(3)/s. The experiments were carried out on carbonate rocks with a n initial permeability from 0.1 x 10(-3) to 0.5 x 10(-3) mo. In some cases, samples were treated by the method of shock decompression to increase thei r permeability; that led to an increase in the initial permeability to 1 x 10(-3) mD. The fluid disequilibrated with respect to carbonate samples was formed by the interaction with granite glass enriched in ore and major elem ents. The evolution of the glass composition, for which a loss of ph, Sn, C u, Li, Cs, and Be is detected, and carbonate, in which Pb, Sn, and Cu becom e concentrated, were studied. Mass transportation in the analogous system w as studied by the physicochemical modeling techniques and experiments. The calculated and experimental results were compared.