文摘
Hydrothermal flow-through experiments were conducted to investigate the mechanism of silica nucleation and precipitation at 430 ¡ãC and 31 MPa. We used elevated Si solutions (CSi = ¡« 375 ppm) with variable Al and Na concentrations. No rock/mineral substrates were used for precipitation. With increasing Al concentrations from 0 to 6.7 ppm at a Na/Al molar ratio of 1.48 in the input solution, the dominant mineral in the products changed from amorphous silica to quartz, and the amount of the products systematically increased. The formation rate of quartz veins and silica scale may be affected by Al and cations in solution.