Experiments were conducted on a synthetic melt plus olivine and a natural melt plus olivine system to determine the influence of H2O and CO2 on the kinetics of melt migration via porous flow. For each experiment, a melt migration couple was formed between a disk of polycrystalline San Carlos olivine and a disk of fully dense glass, which was saturated with either H2O or CO2 and was in chemical equilibrium with San Carlos olivine. For comparison, ‘volatile-free’ glasses were also used. The melt migration experiments were conducted at a temperature of 1300°C and a confining pressure of 300 MPa for times of 6 and 7 hours for couples involving the synthetic and the natural glasses, respectively. Melt migrated into the dunite during the course of the experiment, in order to decrease the interfacial free energy of the system. Melt migration profiles indicate that the amount of volatiles dissolved in the liquids investigated here has only a modest influence on (i) the rate of melt infiltration and (ii) the volume of melt that a rock can absorb.
Bibliographical noteFunding Information:
The authors thank Dr. Ken Chyung at Corning, Inc. for supplying the synthetic glass and John Hunt of the Materials Science Center of Cornell University for assisting with the electron microprobe analyses. We also benefited from discussions with Frank Richter. The support of the National Science Foundation through grant EAR-8916438 is gratefully acknowledged.